Publications on SALVE topics by SALVE authors
Chamberlain, T. W., Biskupek, J., Skowron, S. T., Markevich, A. V., Kurasch, S., Reimer, O., Walker, K. E., Rance, G. A., Feng, X., Muellen, K., Turchanin, A., Lebedeva, M. A., Majouga, A., Nenajdenko, V. G., Kaiser, U. A., Besley, E., & Khlobystov, A. N. (2017). Stop-Frame Filming and Discovery of Reactions at the Single-Molecule Level by Transmission Electron Microscopy. ACS Nano, 11(3), 2509–2520. doi: 10.1021/acsnano.6b08228
Grote, F., Gruber, C., Börrnert, F., Kaiser, U., & Eigler, S. (2017). Thermal Disproportionation of Oxo-Functionalized Graphene. Angewandte Chemie International Edition, 56(31), 9222–9225. doi: 10.1002/anie.201704419
Kinyanjui, M. K., Axmann, P., Mancini, M., Gabrielli, G., Balasubramanian, P., Boucher, F., Wohlfahrt-Mehrens, M., & Kaiser, U. (2017). Understanding the spectroscopic signatures of Mn valence changes in the valence energy loss spectra of Li-Mn-Ni-O spinel oxides. Physical Review Materials, 1(7), 074402. doi: 10.1103/PhysRevMaterials.1.074402
Lee, Z., Hambach, R., Kaiser, U., & Rose, H. (2017). Significance of matrix diagonalization in modelling inelastic electron scattering. Ultramicroscopy, 175, 58–66. doi: 10.1016/j.ultramic.2016.11.011
Lehnert, T., Lehtinen, O., Algara–Siller, G., & Kaiser, U. (2017). Electron radiation damage mechanisms in 2D MoSe2. Applied Physics Letters, 110(3), 033106. doi: 10.1063/1.4973809
Lehnert, Tibor, Kinyanjui, M. K., Ladenburger, A., Rommel, D., Wörle, K., Börrnert, F., Leopold, K., & Kaiser, U. A. (2017). In Situ Crystallization of the Insoluble Anhydrite AII Phase in Graphene Pockets. ACS Nano, 11(8), 7967–7973. doi: 10.1021/acsnano.7b02513
Ma, Y., Ma, Y., Geiger, D., Kaiser, U., Zhang, H., Kim, G.-T., Diemant, T., Behm, J. J., Varzi, A., & Passerini, S. (2017). ZnO/ZnFe2O4/N-doped C micro-polyhedrons with hierarchical hollow structure as high-performance anodes for lithium-ion batteries. Nano Energy, 42, 341–352. doi: 10.1016/j.nanoen.2017.11.030
Skowron, S. T., Chamberlain, T. W., Biskupek, J., Kaiser, U., Besley, E., & Khlobystov, A. N. (2017). Chemical Reactions of Molecules Promoted and Simultaneously Imaged by the Electron Beam in Transmission Electron Microscopy. Accounts of Chemical Research, 50(8), 1797–1807. doi: 10.1021/acs.accounts.7b00078
Stoppiello, C. T., Biskupek, J., Li, Z. Y., Rance, G. A., Botos, A., Fogarty, R. M., Bourne, R. A., Yuan, J., Lovelock, K. R. J., Thompson, P., Fay, M. W., Kaiser, U. A., Chamberlain, T. W., & Khlobystov, A. N., (2017). A one-pot-one-reactant synthesis of platinum compounds at the nanoscale. Nanoscale, 9(38), 14385–14394. doi: 10.1039/C7NR05976K
Wang, Y., Widmann, D., Heenemann, M., Diemant, T., Biskupek, J., Schlögl, R., & Behm, R. J. (2017). The role of electronic metal-support interactions and its temperature dependence: CO adsorption and CO oxidation on Au/TiO2 catalysts in the presence of TiO2 bulk defects. Journal of Catalysis, 354, 46–60. doi: 10.1016/j.jcat.2017.07.029
Zhang, H., Hasa, I., Buchholz, D., Qin, B., Geiger, D., Jeong, S., Kaiser, U. A., & Passerini, S. (2017). Exploring the Ni redox activity in polyanionic compounds as conceivable high potential cathodes for Na rechargeable batteries. NPG Asia Materials, 9(3), e370. doi: 10.1038/am.2017.41
Zhao, X., Kotakoski, J., Meyer, J. C., Sutter, E., Sutter, P., Krasheninnikov, A. V., Kaiser, U. A., & Zhou, W. (2017). Engineering and modifying two-dimensional materials by electron beams. MRS Bulletin, 42(9), 667–676. doi: 10.1557/mrs.2017.184
Björkman, T., Skakalova, V., Kurasch, S., Kaiser, U., Meyer, J. C., Smet, J. H., & Krasheninnikov, A. V. (2016). Vibrational Properties of a Two-Dimensional Silica Kagome Lattice. ACS Nano, 10(12), 10929–10935. doi: 10.1021/acsnano.6b05577
Börner, P., Kaiser, U. A., & Lehtinen, O. (2016). Evidence against a universal electron-beam-induced virtual temperature in graphene. Physical Review B, 93(13), 134104. doi: 10.1103/PhysRevB.93.134104
Börner, P., Kinyanjui, M., Lehnert, T., Köster, J., & Kaiser, U. A. (2016). Characterizing periodic lattice distortions accompanying commensurate charge density waves in single-layer and few-layer 1T-TaSe2. In European Microscopy Congress 2016: Proceedings. Wiley-VCH Verlag GmbH & Co. KGaA. doi: 10.1002/9783527808465.EMC2016.5107
Börrnert, F., Biskupek, J., Lee, Z., Linck, M., Hartel, P., Müller, H., Haider, M., & Kaiser, U. A. (2016). Engineering the Contrast Transfer through the Cc/Cs Corrected 20-80 kV SALVE Microscope. Microscopy and Microanalysis, 22(S3), 880–881. doi: 10.1017/S1431927616005249
Botos, A., Biskupek, J., Chamberlain, T. W., Rance, G. A., Stoppiello, C. T., Sloan, J., Liu, Z., Suenaga, K., Kaiser, U. A., & Khlobystov, A. N. (2016). Carbon Nanotubes as Electrically Active Nanoreactors for Multi-Step Inorganic Synthesis: Sequential Transformations of Molecules to Nanoclusters and Nanoclusters to Nanoribbons. Journal of the American Chemical Society, 138(26), 8175–8183. doi: 10.1021/jacs.6b03633
Dries, M., Janzen, R., Schulze, T., Schundelmeier, J., Hettler, S., Golla-Schindler, U., Jaud, B., Kaiser, U. A., & Gerthsen, D. (2016). The role of secondary electron emission in the charging of thin-film phase plates. In European Microscopy Congress 2016: Proceedings. Wiley-VCH Verlag GmbH & Co. KGaA. doi: 10.1002/9783527808465.EMC2016.4667
Fleischmann, S., Mancini, M., Axmann, P., Golla-Schindler, U., Kaiser, U., & Wohlfahrt-Mehrens, M. (2016). Insights into the Impact of Impurities and Non-Stoichiometric Effects on the Electrochemical Performance of Li2MnSiO4. ChemSusChem, 9(20), 2982–2993. doi: 10.1002/cssc.201600894
Lee, Z., Biskupek, J., Lehnert, T., Rose, H., Linck, M., Hartel, P., Mueller, H., Haider, M., & Kaiser, U. A. (2016). Experimental Contrast of Atomically-resolved Cc/Cs-corrected 20-80kV SALVE Images of 2D-objects Matches Calculations. Microscopy and Microanalysis, 22(S3), 894–895. doi: 10.1017/S1431927616005316
Lee, Z., Kaiser, U., & Rose, H. (2016). Calculation of phase contrast in Cc/Cs-corrected STEM. In European Microscopy Congress 2016: Proceedings. Wiley-VCH Verlag GmbH & Co. KGaA. doi: 10.1002/9783527808465.EMC2016.6235
Linck, M., Hartel, P., Uhlemann, S., Kahl, F., Müller, H., Zach, J., Biskupek, J., Niestadt, M., Kaiser, U. A., & Haider, M. (2016). Performance of the SALVE-microscope: Atomic-resolution TEM Imaging at 20 kV. Microscopy and Microanalysis, 22(S3), 878–879. doi: 10.1017/S1431927616005237
Linck, M., Hartel, P., Uhlemann, S., Kahl, F., Müller, H., Zach, J., Haider, M., Niestadt, M., Bischoff, M., Biskupek, J., Lee, Z., Lehnert, T., Boerrnert, F., Rose, H. H., & Kaiser, U. A. (2016). Chromatic Aberration Correction for Atomic Resolution TEM Imaging from 20 to 80 kV. Physical Review Letters, 117(7), 076101. doi: 10.1103/PhysRevLett.117.076101
Liu, W., Naydenov, B., Chakrabortty, S., Wuensch, B., Hübner, K., Ritz, S., Coelfen, H., Barth, H., Koynov, K., Qi, H., Leiter, R., Reuter, R., Wrachtrup, J., Boldt, F., Scheuer, J., Kaiser, U. A., Sison, M., Lasser, T., Tinnefeld, P., Jelezko, F., Walther, P., Wu, Y., & Weil, T. (2016). Fluorescent Nanodiamond–Gold Hybrid Particles for Multimodal Optical and Electron Microscopy Cellular Imaging. Nano Letters, 16(10), 6236–6244. doi: 10.1021/acs.nanolett.6b02456
Majorovits, E., Angert, I., Kaiser, U., & Schröder, R. R. (2016). Benefits and Limitations of Low-kV Macromolecular Imaging of Frozen-Hydrated Biological Samples. Biophysical Journal, 110(4), 776–784. doi: 10.1016/j.bpj.2016.01.023
Mancini, M., Axmann, P., Gabrielli, G., Kinyanjui, M., Kaiser, U., & Wohlfahrt-Mehrens, M. (2016). A High-Voltage and High-Capacity Li1+xNi0.5Mn1.5O4 Cathode Material: From Synthesis to Full Lithium-Ion Cells. ChemSusChem, 9(14), 1843–1849. doi: 10.1002/cssc.201600365
Markevich, A., Kurasch, S., Lehtinen, O., Reimer, O., Feng, X., Müllen, K., Turchanin, A., Khlobysto, A. N., Kaiser, U. A., & Besley, E. (2016). Electron beam controlled covalent attachment of small organic molecules to graphene. Nanoscale, 8(5), 2711–2719. doi: 10.1039/C5NR07539D
Ophus, C., Ciston, J., Pierce, J., Harvey, T. R., Chess, J., McMorran, B. J., Czarnik, C., Rose, H. H., & Ercius, P. (2016). Efficient linear phase contrast in scanning transmission electron microscopy with matched illumination and detector interferometry. Nature Communications, 7, 10719. doi: 10.1038/ncomms10719
Ophus, C., Ciston, J., Yang, H., Pierce, J., Harvey, T. T., Chess, J., McMorran, B. J., Czarnik, C., Rose, H. H., & Ercius, P. (2016). Phase Contrast Imaging of Weakly-Scattering Samples with Matched Illumination and Detector Interferometry–Scanning Transmission Electron Microscopy (MIDI–STEM). Microscopy and Microanalysis, 22(S3), 460–461. doi: 10.1017/S1431927616003159
Pardini, L., Löffler, S., Biddau, G., Hambach, R., Kaiser, U., Draxl, C., & Schattschneider, P. (2016). Mapping Atomic Orbitals with the Transmission Electron Microscope: Images of Defective Graphene Predicted from First-Principles Theory. Physical Review Letters, 117(3), 036801. doi: 10.1103/PhysRevLett.117.036801
Sahabudeen, H., Qi, H., Glatz, B. A., Tranca, D., Dong, R., Hou, Y., Zhang, T., Kuttner, C., Lehnert, T., Seifert, G., Kaiser, U. A., Fery, A., Zheng, Z., & Feng, X. (2016). Wafer-sized multifunctional polyimine-based two-dimensional conjugated polymers with high mechanical stiffness. Nature Communications, 7, 13461. doi: 10.1038/ncomms13461
Torre, A. L., Rance, G. A., Miners, S. A., Lucas, C. H., Smith, E. F., Fay, M. W., Zoberbier, T., Gimenez-Lopez, M. C., Kaiser, U. A., Brown, P. D., & Khlobystov, A. N. (2016). Ag-catalysed cutting of multi-walled carbon nanotubes. Nanotechnology, 27(17), 175604. doi: 10.1088/0957-4484/27/17/175604
Vinayan, B. P., Diemant, T., Lin, X.-M., Cambaz, M. A., Golla-Schindler, U., Kaiser, U. A., Juergen Behm, R., & Fichtner, M. (2016). Nitrogen Rich Hierarchically Organized Porous Carbon/Sulfur Composite Cathode Electrode for High Performance Li/S Battery: A Mechanistic Investigation by Operando Spectroscopic Studies. Advanced Materials Interfaces, 3(19), n/a-n/a. doi: 10.1002/admi.201600372
Zoberbier, T., Chamberlain, T. W., Biskupek, J., Suyetin, M., Majouga, A. G., Besley, E., Kaiser, U. A., & Khlobystov, A. N. (2016). Investigation of the Interactions and Bonding between Carbon and Group VIII Metals at the Atomic Scale. Small, 12(12), 1649–1657. doi: 10.1002/smll.201502210
Algara-Siller, G., Lehtinen, O., Wang, F. C., Nair, R. R., Kaiser, U., Wu, H. A., Grigorieva, I. V., & Geim, A. K. (2014). Square ice in graphene nanocapillaries. Nature, 519: 443-445, doi: 10.1038/nature14295
Chamberlain, T. W., Biskupek, J., Skowron, S. T., Bayliss, P. A., Bichoutskaia, E., Kaiser, U., & Khlobystov, A. N. (2015). Isotope Substitution Extends the Lifetime of Organic Molecules in Transmission Electron Microscopy. small, 11: 622-629, doi: 10.1002/smll.201402081
Kinyanjui, M. K., Benner, G., Pavia, G., Boucher, F., Habermeier, H. U., Keimer, B., & Kaiser, U. (2015). Spatially and momentum resolved energy electron loss spectra from an ultra-thin PrNiO3 layer. Applied Physics Letters, 106: 203102, doi: 10.1063/1.4921405
Lehtinen, O., Geiger, D., Lee, Z., Whitwick, M. B., Chen, M. W., Kis, A., & Kaiser, U. (2015). Numerical correction of anti-symmetric aberrations in single HRTEM images of weakly scattering 2D-objects. Ultramicroscopy, 151: 130-135, doi: 10.1016/j.ultramic.2014.09.010
Lehtinen, O., Vats, N., Algara-Siller, G., Knyrim, P., & Kaiser, U. (2015). Implantation and Atomic-Scale Investigation of Self-Interstitials in Graphene. Nano letters, 15: 235-241, doi: 10.1021/nl503453u
Lehtinen, O., Komsa, H. P., Pulkin, A., Whitwick, M. B., Chen, M. W., Lehnert, T., Mohn, M. J., Yazyev, O. V., Kis, A., Kaiser, U. A., & Krasheninnikov, A. V. (2015). Atomic scale microstructure and properties of Se-deficient two-dimensional MoSe2. ACS nano, 9: 3274-3283, doi: 10.1021/acsnano.5b00410
Ochedowski, O., Lehtinen, O., Kaiser, U., Turchanin, A., Ban-d’Etat, B., Lebius, H., Karlusic, M., Jaksic, M., & Schleberger, M. (2015). Nanostructuring graphene by dense electronic excitation. Nanotechnology, 26: 465302, doi: 10.1088/0957-4484/26/46/465302
Westenfelder, B., Biskupek, J., Meyer, J. C., Kurasch, S., Lin, X., Scholz, F., Gross, A., & Kaiser, U. (2015). Bottom-up formation of robust gold carbide. Scientific reports, 8: 8891, doi: 10.1038/srep08891
Yoshida, K., Biskupek, J., Kurata, H., & Kaiser, U. (2015). Critical conditions for atomic resolution imaging of molecular crystals by aberration-corrected HRTEM. Ultramicroscopy, 159: 73-80, doi: 10.1016/j.ultramic.2015.08.006
Algara-Siller, G., Lehtinen, O., Turchanin, A., & Kaiser, U. (2014). Dry-cleaning of graphene. Applied Physics Letters, 104, 153115. doi: 10.1063/1.4871997
Algara-Siller, G., Severin, N., Chong, S. Y., Björkman, T., Palgrave, R. G., Laybourn, A., Antonietti, M., Khimyak, Y. Z., Krasheninnikov, A. V., Rabe, J. P., Kaiser, U. A., Cooper, A. I., Thomas, A., & Bojdys, M. J. (2014). Triazine-based graphitic carbon nitride: A two-dimensional semiconductor. Angewandte Chemie - International Edition, 53, 7450–7455, doi: 10.1002/anie.201402191
Cretu, O., Komsa, H., Lehtinen, O., Algara-siller, G., Kaiser, U., Suenaga, K., & Krasheninnikov, A. V. (2014). Experimental Observation of Boron Nitride Chains. ACS Nano, 8(12), 11950–11957. doi: 10.1021/nn5046147
Haider, M., Uhlemann, S., Hartel, P., & Müller, H. (2014). Towards High Resolution in TEM and STEM : What are the Limitations and Achievements. Microscopy and Microanalysis, 20(Suppl 3), 378–379. doi: 10.1017/S1431927614003614
Hartel, P., Linck, M., Kahl, F., Müller, H., & Haider, M. (2014). On Proper Phase Contrast Imaging in Aberration Corrected TEM. Microscopy and Microanalysis, 20(Suppl 3), 926–927. doi: 10.1017/S1431927614006357
Kotakoski, J., Eder, F., Kaiser, U., Mangler, C., & Meyer, J. C. (2014). Irradiation-induced Modifications and Beam-driven Dynamics in Low-dimensional Materials. Microscopy and Microanalysis, 20(Suppl 3), 1726–1727. doi: 10.1017/S1431927614010368
Lebedeva, I. V., Chamberlain, T. W., Popov, A. M., Knizhnik, A. A., Zoberbier, T., Biskupek, J., Kaiser, U. A., Khlobystov, A. N. (2014). The atomistic mechanism of carbon nanotube cutting catalyzed by nickel under an electron beam. Nanoscale, 6, 14877–14890. doi: 10.1039/c4nr05006a
Lee, Z., Rose, H., Lehtinen, O., Biskupek, J., & Kaiser, U. (2014). Electron dose dependence of signal-to-noise ratio, atom contrast and resolution in transmission electron microscope images. Ultramicroscopy, 145, 3–12. doi: 10.1016/j.ultramic.2014.01.010
Lehtinen, O., Geiger, D., Lee, Z., Michael, B., Chen, M., Kis, A., & Kaiser, U. (2014). Numerical correction of anti-symmetric aberrations in single HRTEM images of weakly scattering 2D-objects. Ultramicroscopy, In press. doi: 10.1016/j.ultramic.2014.09.010
Lehtinen, O., Tsai, I. L., Jalil, R., Nair, R. R., Keinonen, J., Kaiser, U. a, & Grigorieva, I. V. (2014). Non-invasive transmission electron microscopy of vacancy defects in graphene produced by ion irradiation. Nanoscale, 6, 6659–6576. doi: 10.1039/c4nr01918k
Uhlemann, S., Müller, H., Zach, J., & Haider, M. (2014). Thermal magnetic fieldnoise : Electron optics and decoherence. Ultramicroscopy, In press. doi: 10.1016/j.ultramic.2014.11.022
Vlasov, I. I., Shiryaev, A., Rendler, T., Steinert, S., Lee, S.-Y., Antonov, D., Vörös, M., Jelezko, F., Fisenko, A. V., Semjonova, L. F., Biskupek, J., Kaiser, U. A., Lebedev, O. I., Sildos, I., Hemmer, P. R., Konov, V., Gali, A., Wrachtrup, J. (2014). Molecular-sized fluorescent nanodiamonds. Nature Nanotechnology, 9(1), 54–8. doi: 10.1038/nnano.2013.255
Algara-Siller, G., Kurasch, S., Sedighi, M., Lehtinen, O., & Kaiser, U. (2013). The pristine atomic structure of MoS2 monolayer protected from electron radiation damage by graphene. Applied Physics Letters, 103: 203107, doi: 10.1063/1.4830036
Algara-Siller, G., Santana, A., Onions, R., Suyetin, M., Biskupek, J., Bichoutskaia, E., & Kaiser, U. A. (2013). Electron-beam engineering of single-walled carbon nanotubes from bilayer graphene. Carbon, 65: 80–86, doi: 10.1016/j.carbon.2013.07.107
Angelova, P., Vieker, H., Weber, N.-E., Matei, D., Reimer, O., Meier, I., Kurasch, S., Biskupek, J., Lorbach, D., Wunderlich, K., Chen, L., Terfort, A., Klapper, M., Müllen, K., Kaiser, U. A., Gölzhäuser, A., & Turchanin, A. (2013). A universal scheme to convert aromatic molecular monolayers into functional carbon nanomembranes. ACS nano, 7: 6489–97, doi: 10.1021/nn402652f. Cited by (1).
Turchanin, A. (2013), Molecular engineering of graphene, carbon nanomembranes and their heterostructures for nanotechnology applications. TNT 2013, PDF, Citation: "Angelova et al. 2013 demonstrated the conversion of carbon nanomembranes into graphene by annealing."
Björkman, T., Kurasch, S., Lehtinen, O., Kotakoski, J., Yazyev, O. V, Srivastava, A., Skakalova, V., Smet, J., Kaiser, U. A., & Krasheninnikov, A. V. (2013). Defects in bilayer silica and graphene: common trends in diverse hexagonal two-dimensional systems. Scientific reports, 3, 3482, doi: 10.1038/srep03482
Campos-Delgado, J, Algara-Siller, G., Santos, C. N., Kaiser, U., & Raskin, J.-P. (2013). Twisted Bi-Layer Graphene: Microscopic Rainbows. Small, 1–5, doi: 10.1002/smll.201300050. Cited by (2).
Campos-Delgado, J., Cancado, Achete, C. A., Jorio, A., & Raskin J.-P. (2013), Raman-Scattering Study of the Phonon Dispersion in Twisted Bi-Layer Graphene. Nano Research, 6: 269-274, doi: 10.1007/s12274-013-0304-z, Citation: "Recently, it has been proven that the electronic properties of twisted bi-layer graphene combined with its reflection on a 100 nm-thick SiO2/Si substrate make twisted bi-layer graphene (θ= 9°-16°) visible through the apperance of blue, yellow or pink/red colorations."
Campos-Delgado, J. (2013), Twisted bilayer graphene: phonon dispersion of microscopic rainbows. Graphene 2013, PDF, Citation: "Our investigations reveal that angles in the range of 9°-11° can be attributed to blue colorations, yellow colorations appear for rotational angles between 11° and 13° and finally pink-reddish colorations are present for angles of 13° up to 15°."
Campos-Delgado, Jessica, Botello-Méndez, A. R., Algara-Siller, G., Hackens, B., Pardoen, T., Kaiser, U., Dresselhaus, M. S., Charlier, J.-C., & Raskin, J.-P. (2013). CVD synthesis of mono- and few-layer graphene using alcohols at low hydrogen concentration and atmospheric pressure. Chemical Physics Letters, 584: 142–146, doi: 10.1016/j.cplett.2013.08.031
Ermakova, A., Pramanik, G., Cai, J.-M., Algara-Siller, G., Kaiser, U., Weil, T., Tzeng, Y.-K., Chang, H. C., McGuinness, L. P., Plenio, M. B., Naydenov, B., & Jelezko, F. (2013). Detection of a Few Metallo-Protein Molecules Using Color Centers in Nanodiamonds. Nano letters, 13: 3305-3309, doi: 10.1021/nl4015233
Huang, P. Y., Alden, J. S., Kurasch, S., Shekhawat, A., Alemi, A. A., Sethna, J. P., Kaiser, U. A., Muller, D. A. (2013). Imaging Atomic Dynamics in 2D Silica Glass with Low-Voltage Aberration- Corrected TEM. Microscopy and Microanalysis, 19: 1224–1225, doi: 10.1017/S1431927613008118
Huang, P. Y., Kurasch, S., Alden, J. S., Shekhawat, A., Alemi, A. A., Mceuen, P. L., Sethna, J. P., Kaiser, U. A., Muller, D. A. (2013). Imaging Atomic Rearrangements in Two-Dimensional Silica Glass: Watching Silica’s Dance. Science: 342: 224–227, doi: 10.1126/science.1242248
Komsa, H.-P., Kurasch, S., Lehtinen, O., Kaiser, U., & Krasheninnikov, A. V. (2013). From point to extended defects in two-dimensional MoS2: Evolution of atomic structure under electron irradiation. Physical Review B, 88: 035301, doi: 10.1103/PhysRevB.88.035301
Lee, Z., Rose, H., Hambach, R., Wachsmuth, P., & Kaiser, U. (2013), The influence of inelastic scattering on EFTEM images – exemplified at 20 kV for graphene and silicon. Ultramicroscopy, 134: 102-112, doi: 10.1016/j.ultramic.2013.05.020.
Lehtinen, O., Kurasch, S., Krasheninnikov, A. V., & Kaiser, U. (2013), Atomic scale study of the life cycle of a dislocation in graphene from birth to annihilation. Nature Communications, 4: 2098, doi: 10.1038/ncomms3098. Cited by (1).
Komsa, H. P., Kurasch, S., Lehtinen, O., Kaiser, U., & Krasheninnikov, A. V. (2013), From point to extended defects in two-dimensional MoS2: Evolution of atomic structure under electron irradiation. Physical Review B, 88: 035301, doi: 10.1103/PhysRevB.88.035301
Matei, D. G., Weber, N. E., Kurasch, S., Wundrack, S., Woszczyna, M., Grothe, M., Weimann, T., Ahlers, F., Stosch, R., Kaiser, U., & Turchanin, A. (2013), Functional Single-Layer Graphene Sheets from Aromatic Monolayers. Advanced Materials, 25: 4146-4151, doi: 10.1002/adma.201300651.
Rasche, B., Isaeva, A., Gerisch, A., Kaiser, M., Van den Broek, W., Koch, C. T., Kaiser, U., & Ruck, M. (2013), Crystal Growth and Real Structure Effects of the First Weak 3D Stacked Topoligical Insulator Bi14Rh3I9. Chemistry Materials, 25: 2359-2364, doi: 10.1021/cm4010823.
Biskupek, J., P. Hartel, M. Haider, & U. A. Kaiser (2012), Effects of residual aberrations explored on single-walled carbon nanotubes. Ultramicroscopy, 116: 1-7, doi: 10.1016/j.ultramic.2012.03.008. Cited by (2)
Schramm, S. M., van der Molen, S. J., & Tromp, R. M. (2012), Intrinsic Instability of Aberration-Corrected Electron Microscopes. Physical Review Letters, 109: 163901, doi: 10.1103/PhysRevLett.109.163901, Citation: "Recent experience with TEM shows that the optimum corrected state can be maintained for only a few minutes, after which the microscope drifts away and must be re-adjusted, a serious concern to microscope designers and users alike."
Tromp, R. M. & Schramm, S. M. (2012), Optimization and Stability of the Contrast Transfer Function in Aberration-Corrected Electron Microscopy. Ultramicroscopy Volume 125: 72-80, doi: 10.1016/j.ultramic.2012.09.007, Citation: "This is important, as stability of the corrected state has become an issue of concern in the practical operation of the TEM."
Chamberlain, T. W., J. Biskupek, G. A. Rance, A. Chuvilin, T. J. Alexander, E. Bichoutskaia, U. A. Kaiser, & A. N. Khlobystov (2012a), Size, Structure, and Helical Twist of Graphene Nanoribbons Controlled by Confinement in Carbon Nanotubes. ACS Nano, 6: 3943-3953, doi: 10.1021/nn300137j. Cited by (15)
Autès, G., & Yazyev, O. V. (2013). Engineering quantum spin Hall effect in graphene nanoribbons via edge functionalization. Physical Review B, 87: 241404, doi: 10.1103/PhysRevB.87.241404, Citation: "Sulfur terminated nanoribbons have been produced recently by fusing sulfur-rich precursor molecules inside a carbon nanotube matrix through heating or electron beam irradiation."
Bichoutskaia, E., Lebedeva, I., Skowron, S., & Popov, A. (2013). Approaches to modelling irradiation-induced processes in transmission electron microscopy. Nanoscale, In Press, doi: 10.1039/C3NR02130K
Cabrera-Sanfelix, P., Arnau, A., & Sanchez-Portal, D. (2013), SAM-like arrangement of thiolated graphene nanoribbons: decoupling the edge state from the metal substrate. Physical Chemistry Chemical Physics, 15: 3233-3242, doi: 10.1039/C2CP43047A, Citation: "In particular, simultaneous saturation of both edges of ZGNRs with sulphur atoms has already been considered."
Chernodub, M. N. (2013), On magnetic-field-induced dissipationless electric current in helicoidal graphene nanoribbons. arXiv preprint, arXiv: 1304.1797
Chernov, A. I., Fedotov, P. V., Talyzin, A. V., Suarez Lopez, I., Anoshkin, I. V., Nasibulin, A. G., Kauppinen, E. I., & Obraztsova, E. D. (2013). Optical Properties of Graphene Nanoribbons Encapsulated in Single-Walled Carbon Nanotubes. ACS nano, In Press, doi: 10.1021/nn4024152, Citation: "The structure of nanoribbons is not uniform in width and contains helical twists. Such twists unambiguously prove the formation of GNRs rather than other types of structures inside SWCNTs."
Kou, L., Tang, C., Frauenheim, T., & Chen, C. (2013), Intrinsic Charge Separation and Tunable Electronic Band Gap of Armchair Graphene Nanoribbons Encapsulated in a Double-Walled Carbon Nanotube. Journal of Physical Chemistry Letters, 4: 1328-1333, doi: 10.1021/jz400037j, Citation: "The microscopic dynamic formation procedure and structural stability of the hybrid GNR@SWCNT have been investigated via molecule dynamics simulation and ab initio studies."
Kou, L., Tang, C., Wehling, T., Frauenheim, T., & Chen, C. (2013). Emergent properties and trends of a new class of carbon nanocomposites: graphene nanoribbons encapsulated in a carbon nanotube. Nanoscale, 5: 3306-3314, doi: 10.1039/C3NR33941F
Qu, C. Q., Wang, C. Y., Qiao, L., Yu, S. S., & Li, H. B. (2013). Transport properties of chemically functionalized graphene nanoribbon. Chemical Physics Letters, 578: 97-101, doi: 10.1016/j.cplett.2013.05.071, Citation: "Khlobystov and co-workers have reported the sulfur-terminated GNRs both theoretically and experimentally."
Santana, A., Zobelli, A., Kotakoski, J., Chuvilin, A., & Bichoutskaia, E. (2013), Inclusion of radiation damage dynamics in high-resolution transmission electron microscopy image simulations: The example of graphene. Physical Review B, 87: 094110, doi: 10.1103/PhysRevB.87.094110, Citation: "Many practically useful materials have been studied using HRTEM with great emphasis on carbon nanostructures."
Wang, X., Zheng, X., & Zeng, Z. (2013), A sp3-type mono-vacancy defect in graphene based Mobius strip. arXiv preprint, arXiv: 1301.1903, Citation: "Especially, in a very recent experiment, the shapes of GNR with different chiral twisted degrees were clearly shown by transmission electron miscroscopy (TEM) images."
Yazyev, O. V. (2013), A Guide to the Design of Electronic Properties of Graphene Nanoribbons. Accounts of Chemical Research, doi: 10.1021/ar3001487, Citation: "So far the surface self-assembly method has been able to produce GNRs with locally armchair edges. A complementary approach exploits self-assembly inside carbon nanotube templates starting from sulfur-rich organic precursors such as tetrathiafulvalene (TTF) under heating (>800 °C) or subject to electron beam irradiation. The width of sulfur-terminated zigzag GNRs obtained using this technique correlates with the diameter of the nanotube template. Two examples of transmission electron microscopy (TEM) images of sulfur-terminated GNRs inside carbon nanotubes are shown in Figure."
Zhang, J., Zhu, Z., Feng, Y., Ishiwata, H., Miyata, Y., Kitaura, R., Dahl, J. E. P., Carlson, R. M. K., Fokina, N. A., Schreiner, P. R., Tomanek, D. & Shinohara, H. (2013), Evidence of Diamond Nanowires Formed inside Carbon Nanotubes from Diamantane Dicarboxylic Acid, Angewandte Chemie International Edition, 52: 3717-3721, doi: 10.1002/anie.201209192, Citation: "Under high-intensity electron-beam irradiation, the encapsulated diamond nanostructures were dehydrogenated and reconstructed into sp2 structures. Termination by heavier elements than hydrogen may suppress this transformation."
Al-Aqtash, N., Li, H., Wang, L., Mei, W. N., & Sabirianov, R. F. (2012), Electromechanical switching in graphene nanoribbons. Carbon, 51: 102-109, doi: 10.1016/j.carbon.2012.08.018, Citation: "Particularly, twisted GNRs are fabricated encapsulated in Carbon Nanotubes (CNTs),"
Ishii, Y., Song, H., Kato, H., Takatori, M., & Kawasaki, S. (2012), Facile bottom-up synthesis of graphene nanofragments and nanoribbons by thermal polymerization of pentacenes. Nanoscale, 4: 6553-6561, doi: 10.1039/C2NR31893H, Citation: "A promising method for controlling graphene morphology with PAH precursors is a template method that uses single-walled carbon nanotubes (SWCNTs) as a reactor. Long-length an width-defined graphene nanoribbons (GNRs) can be synthesized by this method."
Mandal, B., Sarkar, S., Pramanik, A., & Sarkar, P. (2012), Electronic structure and transport properties of sulfur-passivated graphene nanoribbons. Journal of Applied Physics, 112: 113710, doi: 10.1063/1.4768524, Citation: "Chamberlain et al. 2012b both by experimental and theoretical calculation, show that the thermodynamic stability of nanoribbons is dependent on the S-GNR edge structure, and to a lesser extent, the width of the ribbon. According to them, for nanoribbons of similar widths, the polythiaperipolycene-type edges of zigzag S-GNRs are modre stable than the polythiophene-type edges of armchair S-GnRs. Both the edge structure and the width define the electronic properties of S-GNRs which can vary widely from metallic to semiconcuctor to insulator. Ther DFT calculations show that the electronic band structures for the different S-GNRs vary dramatically from semiconductor in the of Z-S-GNRs to metallic to insulator for the A-S-GNRs, depending on the nanoribbons width. On the basis of their generalized gradient approximation (GGA)-Perdew-Burke-Ernzerhof (PBE) results, the authors have demonstrated that 4-A-S-GNR is metallic which creates an open debate whether hopping integrals between edge atoms are capable of opening the band-gap for A-S-GNRs or not."
Chamberlain, T. W., T. Zoberbier, J. Biskupek, A. Botos, U. A. Kaiser, & A. N. Khlobystov (2012b), Formation of uncapped nanometre-sized metal particles by decomposition of metal carbonyls in carbon nanotubes. Chem. Sci., 3: 1919-1924, doi: 10.1039/C2SC01026G. Cited by (3)
Ding, M., Tang, Y., & Star, A. (2013), Understanding Interfaces in Metal-Graphitic Hybrid Nanostructures. Journal of Physical Chemistry Letters, 4: 147-160, doi: 10.1021/jz301711a, Citation: "Other solvent-free methods, such as thermal decomposition of metal complexes have also been employed to generate MNPs on CNTs with pristine interfaces. Furthermore, aberration-corrected HR-TEM (High Resolution-Transmission Electron Microscope) offered effective characterization of the metal-graphitic interface even when MNPs were formed inside of CNTs (Figure). Moreover, prolonged electron beam irradiation could generate defect sites in situ on the carbon nanotube surface; therefore, different interactions at the metal−pristine/defect graphitic interface were visually demonstrated by the different motion behavior of MNPs."
Kharlamova, M. V., Yashina, L. V., & Lukashin, A. V. (2013). Comparison of modification of electronic properties of single-walled carbon nanotubes filled with metal halogenide, chalcogenide, and pure metal. Applied Physics A, 112: 297-304, doi: 10.1007/s00339-013-7808-y, Citation: "It has been shown in the literature that the internal channels of single-walled carbon nanotubes can be filled with substances of different chemical nature including metals."
Takahashi, K., Isobe, S., & Ohnuki, S. (2012), The structural and electronic properties of small osmium clusters (2-14): A density functional theory study. Chemical Physics Letters, 555: 26-30, doi: 10.1016/j.cplett.2012.10.055, Citation: Further research has demonstrated that small Os clusters can be inserted into single-walled carbon nanotubes, which not only stabilize the Os clusters under ambient conditions but also keeps osmium's catalytic activity without being diminished.
Golla-Schindler, U., Algara-Siller, G., Orchowski, A., Wu, Y., Weil, T., & Kaiser, U. A. (2012). First results of 20 kV EFTEM of core-shell QDS with an albumin-derived polypeptide surface coating on graphene. In EMC 2012 15th European Microscopy Congress 16-21 September 2012, Manchester, United Kingdom, 2 pages.
Hebert, C., Biskupek, J., Kaiser, U., Salice, P., Menna, E., Milko, M., & Gao, J. (2012). Dynamical behavior of organic molecules encapsulated in single wall carbon nanotubes investigated by Aberration Corrected-HRTEM. In EMC 2012 15th European Microscopy Congress 16-21 September 2012, Manchester, United Kingdom, 2 pages.
Huang, P. Y., S. Kurasch, A. Srivastava, V. Skakalova, J. Kotakoski, A. V. Krasheninnikov, R. Hovden, Q. Mao, J. C. Meyer, J. Smet, D. A. Muller, & U. A. Kaiser (2012), Direct Imaging of a Two-Dimensional Silica Glass on Graphene. Nano Lett., 12: 1081-1086, doi: 10.1021/nl204423x. Cited by (31)
Ben Romdhane, F., Björkman, T., Rodríguez-Manzo, J. A., Cretu, O., Krasheninnikov, A. V., & Banhart, F. (2013). In-Situ Growth of Cellular Two-Dimensional Silicon Oxide on Metal Substrates. ACS nano, 7, 5175-5180, doi: 10.1021/nn400905k, Citation: "The new discovered quasi-two-dimensional phases of silica can be grown on various transition metals, such as Ru, Pt, Mo, Ni, Pd, and Cu. The thorough microscopic structural characterization of two-dimensional glass was done for the first time."
Boscoboinik, J. A., Yu, X., Yang, B., Shaikhutdinov, S., & Freund, H. J. (2013), Building blocks of zeolites on an aluminosilicate ultra-thin film. Microporous and Mesoporous Materials, 165: 158-162, doi: 10.1016/j.micromeso.2012.08.014, Citation: "A silica bilayer film grown on graphene, with vitreous regions similar to the ones reported by Lichtenstein, was reported by Huang et al. 2012, in which case an even lower population was found for 4-membered rings."
Heyde, M., Simon, G. H., & Lichtenstein, L. (2013), Resolving oxide surfaces - From point and line defects to complex network structures. physica status solidi (b), 250: 895-921, doi: 10.1002/pssb.201248597, Citation: "A bilayer of vitreous silica film was observed on graphene by scanning transmission electron microscopy (STEM)."
Kaiser, U. A. (2013) Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope, PDF, Citation: "Moreover, we discuss structural changes under the influence of Joule heating and address the basic question how the amorphous phase of 2D objects is formed and can it can be described from direct images."
Norman, P. E., Schwartzentruber, T. E., Leverentz, H. R., Luo, S., Meana-Pañeda, R., Paukku, Y., & Truhlar, D. G. (2013), The Structure of Silica Surfaces Exposed to Atomic Oxygen. The Journal of Physical Chemistry C, 117: 9311-9321, doi: 10.1021/jp4019525, Citation: "Recent experiments on dry two-dimensional amorphous silica glasses may also be relevant."
Shaikhutdinov, S., & Freund, H. J. (2013), Metal-Supported Aluminosilicate Ultrathin Films as a Versatile Tool for Studying the Surface Chemistry of Zeolites. ChemPhysChem, 14: 71-77, doi: 10.1002/cphc.201200826, Citation: "The histogram (Figure) reveals a rather broad distribution between N=4 and 8. This distribution has a peak at 6MR, and 5MR and 7MR being the next most abundant species, with negligible amounts of 4MRs. The lack of the 4MR was also observed in the recent study using HRTEM."
Sorokin, P. B., & Chernozatonskii, L. A. (2013). Graphene-based semiconductor nanostructures. Uspekhi Fizicheskikh Nauk, 183: 113-132, doi: 10.3367/UFNe.0183.201302a.0113, Citation: "Two-dimensional structures of compounds such as quartz glass SiO2 have been obtained by low-voltage aberration-corrected electron microscopy."
Wilson, M., Kumar, A., Sherrington, D., & Thorpe, M. F. (2013), Modeling vitreous silica bilayers. arXiv preprint arXiv: 1303.5898, Citation: " The continuous random network model of network glasses is widely accepted as a model for materials like vitreous silica and amorphous silicon. Although it is more than eighty years since Zachariasen proposed this model of glasses, experimental evidence has been compelling over the years, especially through diffraction experiments, but never quite conclusive as the probability of rings of various sizes has been elusive to determine experimentally. This situation has now changed dramatically with the accidental discovery and (S)TEM imaging of the two dimensional bilayer of vitreous silica. Here, not only the distribution of rings, but the actual detailed atomic ring structure has been imaged for the 1st time in real space, removing all speculation from this subject (at least for this class of materials). This is the 1st time that we are aware of real space imaging of a random network and as such represents a tour de force. Because of the amorphous nature of the monolayer and the need for vertical oxygen bridges connecting the upper and lower layers, it is necessary for the two layers to have the same ring structure and be topologically identical to form a complete corner sharing tetrahedral network. The result that the two layers are also geometrical mirror images of each other is quite surprising at 1st sight in a system that is a priori without any symmetry, but comes about from understanding the nature of the constraints within the network as explained in the next section. This is verified by our detailed atomic modeling and also by the experimental results which show that the upper and lower layers lie one on top of the other as required by the symmetry plane. Thin vitreous SiO2 films (interpreted as bilayers) have been grown on graphene. Figure shows the experimentally-obtained and computer-generated ring statistics. This metric conveniently captures the major changes in ring statistics from sample to sample in a single number. The values of the variances in the ring size distribution µ2 by Huang et al. 2012 for the data presented in this Figure are 0.886.
Wright, A. C., & Thorpe, M. F. (2013), Eighty years of random networks. physica status solidi (b), 250: 931-936 doi: 10.1002/pssb.201248500, Citation: "This raises an interesting philosophical question. Supposing an extremely large model (say 1 000 000 atoms) could be generated, which was in perfect agreement with all of the experimental data within their given uncertainties. Even in this case, it would still be only one of a potentially infinite number of possible atomic arrangements, and there is no way of telling whether it is indeed the ‘correct’ structure. A much more important question, however, is how could it be established whether the model actually comprises a random network as defined above? Obviously, it would be possible to check the distributions of bond and torsion angles, but what about the network topology? Thus it may be concluded that, even though an ideal Warren-Zachariasen random network is easy to define theoretically, it is still unclear as to how best such networks can be generated in practice, and similarly it remains unknown as to how closely this first-order model approaches the structure of real network glasses. After 80 years, experiments and theory do not yet agree as well as one would like. This is probably due to the difficulty of exploring all the possible distributions of rings of bonds and correlations between adjacent rings of bonds, etc. Indeed our inability to get compelling direct experimental information about rings remains a continuing road block. This may be finally solved by going back to a twodimensional glass like amorphous graphene, where the rings can be imaged directly, in a way not possible for threedimensional networks. This has been recently accomplished in some remarkable experiments for a bilayer of vitreous silica using TEM imaging. When this happens, Zachariasen’s famous sketch of a glassy network will finally be fully demonstrated (although without the oxygen atoms) with a full two-dimensional atomic network topology, including medium range order, visible to all."
Zhang, K., Li, H., Li, L., & Bian, X. F. (2013), Why does the second peak of pair correlation functions split in quasi-two-dimensional disordered films? Applied Physics Letters, 102: 071907-071907, doi: 10.1063/1.4793187, Citation: "Huang et al. reported the accidental discovery of 2D amorphous silica supported on graphene. Our theoretical results are in good agreement with the experiments by Huang et al."
Buchner, C., Lichtenstein, L., & Heyde, M. (2012), Ein glasklares Modell. Nachrichten aus der Chemie, 60: 861-864, doi: 10.1515/nachrchem.2012.60.9.861, Citation: "."
Dawson, C. J., Kapko, V., Thorpe, M. F., Foster, M. D., & Treacy, M. M. (2012), Flexibility As an Indicator of Feasibility of Zeolite Frameworks. Journal of Physical Chemistry C, 116: 16175-16181, doi: 10.1021/jp2107473, Citation: "Many of the flexible frameworks with densities below 10 T-atoms/nm3 are found to exist below the feasibility line. At these low densities, frameworks frequently contain large channels whose walls are thin bisilicate layer structures. Such bisilicate layers frequently comprise locally rigid structures, such as double five-ring and double six-ring units that are otherwise part of a globally flexible, low-energy, framework. An example of such a channel wall structure is shown in Figure and Figure. Recently, stand-alone bisilicate films have been demonstrated."
Heyde, M., Lichtenstein, L., Buchner, C., Stuckenholz, S., & Freund, H. J. (2012), From Crystalline to Vitreous 2D Silica - a Complementary nc-AFM and STM Study, online at ncafm12.fzu.cz, Citation: "The existence of a 2D silica glass on a graphene support has been shown by scanning transmission electron microscopy suggesting that further 2D glass systems may be prepared."
Huang, P. Y., Hovden, R., Mao, Q., Muller, D. A., Kurasch, S., Kaiser, U. A., Kotakoski, J., Krasheninnikov, A., Srivastava, A., Skakalova, V., Smet, J., & Meyer, J. (2012), Quantitative Atomic-resolution Imaging and Spectroscopy of a 2D Silica Glass. Microscopy and Microanalysis, 18: 340-341, doi: 10.1017/S1431927612003558, Citation: "Here, we investigate a two-dimensional (2D) glass using atomic resolution, aberration-corrected annular dark-field scanning transmission electron microscopy (ADF-STEM) and electron energy-loss spectroscopy (EELS). By direct measurement and comparison with simulation, we are able to identify an unknown material and develop three-dimensional structural models that match our experimental images and spectra. We are able to distinguish between chemically and structurally similar models whose structures differ by a single silicon atom in projection. These results determine the composition and bonding of the 2D glass as SiO2 formed from a bilayer of (SiO4)2- tetrahedra."
Huang, P. Y., Meyer, J. C., & Muller, D. A. (2012), From atoms to grains: Transmission electron microscopy of graphene. MRS bulletin, 37: 1214-1221, doi: 10.1557/mrs.2012.183, Citation: "For (S)TEM, singlelayer graphene substrates provide a built-in reference for mass-thickness determination, enabling quantitative atomic imaging and spectroscopy of nanomaterials with atomic-layer sensitivity, which is typically a major challenge. A study has investigated a two-dimensional silica glass on single-layer graphene substrate."
Kaiser, U. A. (2012), Low-voltage TEM-current status and future prospects. EMC 2012, PDF, Citation: "Basic questions in physics and chemistry such as ― What is the exact atomic structure of defects ? ― or ― How is the dynamic behaviour ― or ― What are the structures of amorphous materials? ― and the like constantly addressed over the past by our respected colleague and mutual friend, David Cockayne, microscopist now begin to answer in direct space on the atom-by-atom level."
Komsa, H. P., & Krasheninnikov, A. V. (2012), Two-Dimensional Transition Metal Dichalcogenide Alloys: Stability and Electronic Properties. Journal of Physical Chemistry Letters, 3: 3652-3656, doi: 10.1021/jz301673x, Citation: "Recently, several two-dimensional (2D) materials, such as graphene, hexagonal boron-nitride (h-BN), and silica bilayer were manufactured."
Kostinski, S., Pandey, R., Gowtham, S., Pernisz, U., & Kostinski, A. (2012), Diffusion of Water Molecules in Amorphous Silica. Electron Device Letters IEEE, 33, 863-865, doi: 10.1109/LED.2012.2189750, Citation: "Recent work suggests that there exists a weak coupling between the structure of bilayer a-SiO2 films and that of their substrates (e.g. graphene). This may provide a platform for growing a-SiO2 thin films with preferred ring-size distributions."
Kurasch, S., Huang, P. Y., Kotakoski, J., Krasheninnikov, A. V., Hovden, R., Mao, Q., Meyer, J. C., Muller, D. A., & Kaiser, U. A. (2012), Atomic scale imaging and spectroscopy of 2D silica glass on graphene, EMC 2012, PDF, Citation: "To date, most of the 2D materials studied by TEM were crystalline and, despite the huge improvements in machinery during the last decades, direct imaging of individual atoms in unordered 3D materials has not been possible so far as only the 2D projections are observed. We found that a 2D silica layer was formed on graphene during a CVD growth on Cu foil. Here we show that this allows atom-by-atom (S)TEM imaging and spectroscopy of the glass."
Lichtenstein, L. (2012), The Structure of Two-Dimensional Vitreous Silica, PhD dissertation, Freie Universitat Berlin, online at: d-nb.info, Citation: "The weak coupling to the substrate might be one of the driving forces for the formation of vitreous patches. Huang and coworkers have also observed crystalline and vitreous silica bilayer patches on one and the same, crystalline substrate (graphene). Defects at the interface might be another influence on the film structure. These findings prove the existence of a new class of materials: two-dimensional glasses. Figure.
Lichtenstein, L., Buchner, C., Stuckenholz, S., Heyde, M., & Freund, H. J. (2012), Enhanced atomic corrugation in dynamic force microscopy - The role of repulsive forces. Applied Physics Letters, 100: 123105-123105, doi: 10.1063/1.3696039 , Citation: "Shortly after, the existence of a thin silica glass was shown on graphene."
Lichtenstein, L., Heyde, M., & Freund, H. J. (2012), Atomic Arrangement in Two-Dimensional Silica: From Crystalline to Vitreous Structures. Journal of Physical Chemistry C, 116: 20426-20432, doi: 10.1021/jp3062866, Citation: "Huang et al. 2012 also observed crystalline and vitreous silica bilayer patches on one and the same, crystalline substrate (graphene)."
Lichtenstein, L., Heyde, M., & Freund, H. J. (2012), Crystalline-Vitreous Interface in Two Dimensional Silica. Physical Review Letters, 109: 106101, doi: 10.1103/PhysRevLett.109.106101, Citation: "By comparing the pair correlation functions, we could prove that the 2D film is a good model of a three dimensional (3D) glass. Our results were confirmed by transmission electron microscopy experiments of 2D vitreous silica prepared on graphene."
Norman, P., & Schwartzentruber, T. (2012), A finite-rate model for oxygen-silica catalysis through computational chemistry simulation. AIP Conference Proceedings, 1501: 1137-1144, doi: 10.1063/1.4769669, Citation: "."
Pacchioni, G. (2012), Two-Dimensional Oxides: Multifunctional Materials for Advanced Technologies. Chemistry-A European Journal, 18: 10144-10158, doi: 10.1002/chem.201201117, Citation: "A similar, but this time accidental, discovery of a two-dimensional silica glass supported on graphene has been reported by Huang et al. Figure."
Panthani, M. G., Hessel, C. M., Reid, D., Casillas, G., Jose-Yacaman, M., & Korgel, B. A. (2012), Graphene-Supported High-Resolution TEM and STEM Imaging of Silicon Nanocrystals and their Capping Ligands. Journal of Physical Chemistry C, 116, 22463-22468, doi: 10.1021/jp308545q, Citation: "Graphene supports have enabled imaging of a two-dimensional silica glass."
Susi, T., Kotakoski, J., Arenal, R., Kurasch, S., Jiang, H., Skakalova, V., Stephan, O., Krasheninnikov, A. V., Kauppinen, E. I., Kaiser, U. A., & Meyer, J. C. (2012), Atomistic Description of Electron Beam Damage in Nitrogen-Doped Graphene and Single-Walled Carbon Nanotubes. ACS nano, 6: 8837-8846, doi: 10.1021/nn303944f, Citation: "The intermediate spatial resolution offered by electron energy loss spectroscopy (EELS) in transmission electron microscopy (TEM) instruments has been particularly useful for nanotubes, but technical limitations have hitherto not allowed an unambiguous identification of the dopant structures. More recently, cutting-edge developments in instrumentation have enabled atom-by-atom analysis of graphene and similar materials and even direct imaging of nitrogen sites."
Wang, L., Travis, J. J., Cavanagh, A. S., Liu, X., Koenig, S. P., Huang, P. Y., George, S. M., & Bunch, J. S. (2012), Ultrathin Oxide Films by Atomic Layer Deposition on Graphene. Nano letters, 12: 3706-3710, doi: 10.1021/nl3014956, Citation: "The integration of graphene with other two dimensional (2D) or quasi-2D materials may also lead to new functional properties for the composite materials."
Wang, W. S., Wang, D. H., Qu, W. G., Lu, L. Q., & Xu, A. W. (2012), Large ultrathin anatase TiO2 nanosheets with exposed {001} facets on graphene for enhanced visible light photocatalytic activity. Journal of Physical Chemistry C, 116: 19893-19901, doi: 10.1021/jp306498b, Citation: "In other words, GO as a template plays a decisive role in the formation of large ultrathin anatase TiO2 nanosheet enwrapped {001} facets, because graphene, providing a support membrane, can stabilize 2D materials."
Wilson, M. (2012), Model investigations of network-forming materials. Physical Chemistry Chemical Physics, 14: 12701-12714, doi: 10.1039/C2CP41644A, Citation: "Recent work has uncovered the possibility of generating genuine near-two dimensional structures for SiO2."
Yu, X., Yang, B., Anibal Boscoboinik, J., Shaikhutdinov, S., & Freund, H. J. (2012), Support effects on the atomic structure of ultrathin silica films on metals. Applied Physics Letters, 100: 151608-151608, doi: 10.1063/1.3703609, Citation: "Very recently, it has been reported the (accidental) formation of silica bilayer on graphene that represents an oxygenresistant, weakly bonded support."
Kaiser, U. A. (2012). Low-voltage TEM - current status and future prospects. In EMC 2012 15th European Microscopy Congress 16-21 September 2012, Manchester, United Kingdom, 2–3.
Kinyanjui, M. K., C. Kramberger, T. Pichler, J. C. Meyer, P. Wachsmuth, G. Benner & U. A. Kaiser (2012), Direct probe of linearly dispersing 2D interband plasmons in a free-standing graphene monolayer. EPL, 97: 57005, doi: 10.1209/0295-5075/97/57005. Cited by (9)
Liou, S. C., Chu, M. W., Sankar, R., Huang, F. T., Shu, G. J., Chou, F. C., & Chen, C. H. (2013), Plasmons dispersion and nonvertical interband transitions in single crystal Bi_{2} Se_{3} investigated by electron energy-loss spectroscopy. Physical Review B, 87: 085126, doi: 10.1103/PhysRevB.87.085126, Citation: "While the π + σ plasmon displays the typical parabolic dispersion with q2 dependence, the π plasmon reveals a linear dispersion as a function of momentum-transfer (q), similar to what was reported for the two-dimensional plasmon in graphene."
Kaiser, U. A. (2013), Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope. PDF, Citation: "We determine the dispersion behavior for π and π+σ plasmons in free-standing single-layer graphene."
Kaiser, U. A. (2012), Low-Voltage TEM to explore physics and chemistry of low-dimensional and low-atomic number materials on the atomic scale. PDF, Citation: "We demonstrate, moreover, by means of image calculations that at 20 kV the contrast, even for graphene, a one-carbon-atom-thin material, cannot be described by means of the weak phase-object approximation, and that correction of chromatic aberration is a prerequisite for obtaining highresolution, high-contrast zero-loss and energy-filtered inelastic images."
Kaiser, U. A. (2012), Low-voltage TEM-current status and future prospects. EMC 2012, PDF, Citation: "In EELS mode we take advantage of the exceptionally low background noise at low voltages enabling the investigation of plasmons in single and multi-layer graphene using angle-resolved EELS"
Politano, A., Campi, D., Formoso, V., & Chiarello, G. (2013). Evidence of confinement of the Pi plasmon in periodically rippled graphene on Ru (0001). Phys. Chem. Chem. Phys., 15: 11356, doi: 10.1039/c3cp51954f, Citation: "In graphitic systems, the ordinary Pi or interband plasmon energy is 5–7 eV."
Politano, A., & Chiarello, G. (2013). Quenching of plasmons modes in air-exposed graphene-Ru contacts for plasmonic devices. Applied Physics Letters, 102: 201608, doi: 10.1063/1.4804189, Citation: "."
Politano, A., & Chiarello, G. (2013), Unravelling suitable graphene-metal contacts for graphene-based plasmonic devices. Nanoscale, In Press, doi: 10.1039/C3NR02027D, Citation: "."
Politano, A., Marino, A. R., & Chiarello, G. (2012), Effects of a humid environment on the sheet plasmon resonance in epitaxial graphene. Physical Review B, 86: 085420, doi: 10.1103/PhysRevB.86.085420, Citation: "A distinct low-energy collective electronic excitation exists in graphene: the π or interband plasmon at 5-7 eV."
Sarma, S. D., & Li, Q. (2013). Intrinsic plasmons in two-dimensional Dirac materials. Physical Review B, 87: 235418, doi: 10.1103/PhysRevB.87.235418, Citation: "Our interest here is in low-energy ~meV two-dimensional (2D) collective modes and not very high-energy ~ 10 eV band or so-called π plasmons where the whole valence band charge response is involved."
Komsa, H.-P., J. Kotakoski, S. Kurasch, O. Lehtinen, U. A. Kaiser, A. V. Krasheninnikov (2012), Two-dimensional transition metal dichalcogenides under electron irradiation: defect production and doping. Phys. Rev. Lett., 109: 035503, doi: 10.1103/PhysRevLett.109.035503. Cited by (22)
Berseneva, N., Gulans, A., Krasheninnikov, A. V., & Nieminen, R. M. (2013), Electronic structure of boron nitride sheets doped with carbon from first-principles calculations. Physical Review B, 87: 035404, doi: 10.1103/PhysRevB.87.035404, Citation: "The technique, which can be referred to as a combination of electron irradiation and beam-assisted deposition, can be applied to various 2D materials. Indeed, filling of vacancies created by the electron beam in molybdenum disulfide was recently demonstrated in the experiments."
Chang, J., Larentis, S., Tutuc, E., Register, L. F., & Banerjee, S. K. (2013). Atomistic simulation of doping by adatoms in monolayer MoS2. arXiv preprint, arXiv: 1305.7162, Citation: "Doping by vacancies or substitutional impurity atoms in the monolayer MoS2 has been reported."
Cheng, Y. C., Zhu, Z. Y., Mi, W. B., Guo, Z. B., & Schwingenschlogl, U. (2013), Prediction of two-dimensional diluted magnetic semiconductors: Doped monolayer MoS2 systems. Physical Review B, 87: 100401, doi: 10.1103/PhysRevB.87.100401, Citation: "In fact, it has been demonstrated that a S vacancy is easier formed under electron irradiation than a Mo vacancy. This also demonstrated that the vacancies can be consecutively filled with other atomic species. For example, F, Cl, Br, and I can donate electrons to the MoS2 and fill the unoccupied shallow impurity states near the conduction bands."
Dolui, K., Rungger, I., Pemmaraju, C. D., & Sanvito, S. (2013), Ab-initio study on the possible doping strategies for MoS2 monolayers. arXiv preprint, arXiv: 1304.8056v1, Citation: "The only viable formation channel is offered by filling S vacancies, which have been recently demonstrated to form with relatively ease. Therefore, it appears that a strategy for doping at the S site may be that of growing S poor samples and then of filling the vacancies with an appropriate donor/acceptor sulfur replacement. In contrast, the adsorption of H produces a spin-split state 1 eV below the CBM, i.e. roughly at midgap of the LSDA band-gap [see Figure]. As such we conclude that H is not a shallow donor for MoS2, in good agreement with the recent theoretical results."
Enyashin, A. N., Bar-Sadan, M., Houben, L., & Seifert, G. (2013), Line Defects in Molybdenum Disulfide Layers. arXiv preprint, arXiv: 1304.3701, Citation: "In earlier studies of the MoS2 monolayer or nanotubes only zero-dimensional defects (vacancies, substitutional dopants, square-like defects) were considered. These defects mainly create localized states within the band gap of pristine MoS2 or cause a shift of the Fermi level into the Mo4dz2 band."
Kaiser, U. A. (2013) Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope, PDF, Citation: "We discuss the determination of knock-on damage thresholds in two-dimensional objects."
Komsa, H. P., Kurasch, S., Lehtinen, O., Kaiser, U., & Krasheninnikov, A. V. (2013). From point to extended defects in two-dimensional MoS2: Evolution of atomic structure under electron irradiation. Physical Review B, 88: 035301, doi: 10.1103/PhysRevB.88.035301, Citation: "Free standing monolayer MoS2 samples (note that the monolayer consists of three atomic layers) were prepared by mechanical exfoliation of natural MoS2 bulk crystals, followed by characterization via optical microscopy on a Si + 90 nm SiO2 substrate and transfered to a perforated TEM support film (Quantifoil). During imaging, new vacancies are continuously produced. The threshold electron energy for vacancy creation is very close to 95 keV. In the case of single vacancy (SV), there is an unoccupied level in the upper half of the gap and an occupied level nearly degenerate with valence band maximum (VBM). For (SV) lines, P, As, F, Cl, and Br all lead to formation of defect bands with fairly small band widths, but still predominantly retaining their acceptor and donor characteristics found for filling of isolated vacancies. Lines of naked vacancies are likely of very limited practical use due to their reactivity. However, the vacancy lines may be filled, and consequently functionalized, by other atoms as we reported for isolated vacancies. The energies of the substitution processes tend to be slightly higher in the case of double vacancy (DV) substitution, due to the low total energy of the DV vacancy lines. Therefore, in some cases, the single atom substitution energies given in Komsa et al. 2012 may better quantify the stability."
Krasheninnikov, A. V., Komsa, H. P., Kurasch, S., Kotakoski, J., Lehtinen, O., & Kaiser, U. A. (2013) 2D Transition-Metal Dichalcogenides: Doping, Alloying and Atomic Structure Engineering Using Electron Beam, DOC online, Citation: "By combining first-principles simulations with high-resolution transmission electron microscopy experiments, we study the evolution of atomically thin layers of transition metal dichalcogenides (TMDs) under electron irradiation. We show that vacancies produced by the electron beam agglomerate and form line structures, which can be used for engineering materials properties. We also study the radiation hardness of 2D TMD materials."
Liu, Y., Ang, R., Lu, W. J., Song, W. H., Li, L. J., & Sun, Y. P. (2013). Superconductivity induced by Se-doping in layered charge-density-wave system 1T-TaS 2-x Se x. Applied Physics Letters, 102: 192602, doi: 10.1063/1.4805003, Citation: "In the past few years, especially after the synthesis of monolayer MoS2, transition-metal dichalcogenides (TMDs) have triggered a tremendous wave of excitement in the scientific community due to their unique structural properties and semiconducting nature."
Liu, X., Xu, T., Wu, X., Zhang, Z., Yu, J., Qiu, H., Hong, J. H., Jin, C. H., Li, J. X., Wang, X. R., Sun, L. T. & Guo, W. (2013), Top-down fabrication of sub-nanometre semiconducting nanoribbons derived from molybdenum disulfide sheets. Nature Communications, 4: 1776, doi: 10.1038/ncomms2803, Citation: "Under the irradiation of electron beam, defects can be created in the thin 2D sheet once the beam energy exceeds the knock-on damage threshold of the sheet. To estimate the threshold energy of irradiation-induced atom displacement, we calculate the nonrelaxed formation energy of vacancy as Ef = Evac-Eperfect + µx, where Eperfect, Evac and µx are energies of the perfect structure, the non-relaxed structure with mono-vacancy and the removed isolated atom, respectively"
Ochedowski, O., Marinov, K., Wilbs, G., Keller, G., Scheuschner, N., Severin, D., Bender, M., Maultzsch, J., Tegude, F. J., & Schleberger, M. (2013). Radiation hardness of graphene and MoS2 field effect devices against swift heavy ion irradiation. Journal of Applied Physics, 113: 214306, doi: 10.1063/1.4808460, Citation: "The atom displacement energy for Mo and S atoms in MoS2 is 7 eV."
Sadhukhan, M., & Barman, S. (2013). Bottom-up fabrication of two-dimensional carbon nitride and highly sensitive electrochemical sensors for mercuric ions. Journal of Materials Chemistry A, 1: 2752-2756, doi: 10.1039/C3TA01523H, Citation: "Komsa et al. 2012 demonstrate a bottom-up fabrication method for the production of single or few layered 2D materials."
Sahin, H., Tongay, S., Horzum, S., Fan, W., Zhou, J., Li, J., Wu, J., & Peeters, F. M. (2013), Anomalous Raman spectra and thickness-dependent electronic properties of WSe2. Physical Review B, 87: 165409, doi: 10.1103/PhysRevB.87.165409, Citation: "Recently, possibility of vacancy creation in Transition Metal Dichalcogenides (TMDs) under electron irradiation has been reported."
Song, X., Hu, J., & Zeng, H. (2013), Two-dimensional semiconductors: recent progress and future perspectives. Journal of Materials Chemistry C, 1: 2952-2969, doi: 10.1039/C3TC00710C, Citation: "Since then, inspiring results were achieved in the synthesis of layered MoS2, which provide a potent research platform for future fundamental studies of the basic properties and related application of 2D crystal materials."
van der Zande, A. M., Huang, P. Y., Chenet, D. A., Berkelbach, T. C., You, Y., Lee, G. H., Heinz, T. F., Reichman, D. R., Muller, D. A. & Hone, J. C. (2013). Grains and grain boundaries in highly crystalline monolayer molybdenum disulphide. Nature materials, 12: 554-561, doi: 10.1038/nmat3633, Citation: "Defects readily form under extended imaging."
Xu, M., Liang, T., Shi, M., & Chen, H. (2013), Graphene-Like Two-Dimensional Materials. Chemical Reviews, 113: 3766-3798, doi: 10.1021/cr300263a, Citation: "Electron irradiation-induced defects during the patterning need to be taken into consideration."
Yue, Q., Chang, S., Qin, S., & Li, J. (2013), Functionalization of monolayer MoS2 by substitutional doping: A first-principles study. Physics Letters A., 377: 1362-1367, doi: 10.1016/j.physleta.2013.03.034, Citation: "Very recently, Komsa et al. observed the vacancy formation in 1H-MoS2 under exposure to 80 keV electron-beam irradiation inside a high-resolution transmission electron microscope (HRTEM) and then the filling of vacancies with substitutional impurity atoms, validating the above expectation. We follow the two-step process to dope 1H-MoS2, including vacancy creation and then incorporation of dopant into the vacancy site, as suggested by the electron-beam mediated substitutional doping scheme. We first turn to single S vacancy (VS) in MoS2 sheet [Figure], which is energetically easier to be produced than Mo vacancy (VMo) under electron-beam irradiation."
Zhou, Y., Yang, P., Zu, H., Gao, F., & Zu, X. (2013). Electronic structures and magnetic properties of MoS2 nanostructures: atomic defect, nanohole, nanodot and antidot. Phys. Chem. Chem. Phys., 15: 10385-10394, doi: 10.1039/C3CP50381J, Citation: "Recently atomic defects have been observed in, e.g., MoS2 sheets."
Zhou, W., Zou, X., Najmaei, S., Liu, Z., Shi, Y., Kong, J., Lou, J., Ajayan, P. M., Yakobson, B. I., & Idrobo, J. C. (2013). Intrinsic Structural Defects in Monolayer Molybdenum Disulfide. Nano letters, 13: 2615-2622, doi: 10.1021/nl4007479, Citation: "The knock-on damage threshold has been calculated for MoS2."
Komsa, H. P., & Krasheninnikov, A. V. (2012), Two-Dimensional Transition Metal Dichalcogenide Alloys: Stability and Electronic Properties. Journal of Physical Chemistry Letters, 3: 3652-3656, doi: 10.1021/jz301673x, Citation: "Alloying could be achieved through vacancy production and atomic substitution under electron beam."
Mathew, S., Gopinadhan, K., Chan, T. K., Yu, X. J., Zhan, D., Cao, L., Rusydi, A., Breese, M. B. H., Dhar, S., Shen, Z. X., Venkatesan, T., & Thong, J. T. (2012), Magnetism in MoS2 induced by proton irradiation. Applied Physics Letters, 101: 102103, doi: 10.1063/1.4750237, Citation: "An estimate of the defect density created by the proton beam in MoS2 can be determined from Monte Carlo simulations (SRIM 2008) using full damage cascade. The displacement energy of Mo and S for the creation of a Frenkel pair used for the calculation is 20 eV and 6.9 eV, respectively, as reported by Komsa et al. 2012 in a recent study of electron irradiation hardness of transition metal dichalcogenides. According to this calculation the 2 MeV proton comes to rest at a depth of 31 µm from the surface. The distance between vacancies estimated at the surface and at the end of range after irradiating with 1 × 1018 ions/cm2 is 6.3 Å and 2.7 Å, respectively. These calculated values are overestimates because the annealing of defects and crystalline nature of the target have not been incorporated in SRIM simulations."
Susi, T., Kotakoski, J., Arenal, R., Kurasch, S., Jiang, H., Skakalova, V., Stephan, O., Krasheninnikov, A. V., Kauppinen, E. I., Kaiser, U. A., & Meyer, J. C. (2012), Atomistic Description of Electron Beam Damage in Nitrogen-Doped Graphene and Single-Walled Carbon Nanotubes. ACS nano, 6: 8837-8846, doi: 10.1021/nn303944f, Citation: "We point out that static vacancy formation energy calculations can in some case give reasonable estimates of TD, defined as the kinetic energy sufficient to displace the atom from its lattice site without an immediate recombination with the resulting vacancy."
Kurasch, S., Huang, P. Y., Kotakoski, J., Krasheninnikov, A. V, Hovden, R., Mao, Q., & Meyer, J. C. (2012). Atomic scale imaging and spectroscopy of 2D silica glass on graphene. In EMC 2012 15th European Microscopy Congress 16-21 September 2012, Manchester, United Kingdom, 2 pages.
Kurasch, S., J. Kotakoski, O. Lehtinen, V. Skakalova, J. H. Smet, C. Krill III, A. V. Krasheninnikov, and U. A. Kaiser (2012), Atom-by-Atom Observation of Grain Boundary Migration in Graphene. Nano Lett., 12: 3168-3173, doi: 10.1021/nl301141g. Cited by (14)
Bichoutskaia, E., Lebedeva, I., Skowron, S., & Popov, A. (2013). Approaches to modelling irradiation-induced processes in transmission electron microscopy. Nanoscale, 5: 6677-6692, doi: 10.1039/C3NR02130K
Biro, L. P.(1,3), & Lambin, P.(2) (2013), Grain boundaries in graphene grown by chemical vapor deposition. New Journal of Physics, 15: 035024, doi: 10.1088/1367-2630/15/3/035024, Citation: "Indeed, experimental HRTEM images show that the small, strongly disordered polygon clusters surrounded by crystalline graphene tend to reduce their size under e-beam irradiation (see [Figure]). In revealing the details of the atomic structure of the GBs, HRTEM is among the most effective. A detailed GB study using HRTEM revealed that under the conditions of e-beam irradiation, GBs are predominantly constructed of continuous chains of pentagon-heptagon pairs and the GBs tend to take on meandering, locally curved configurations. Movies taken on the GB evolution in the electron microscope convincingly show that once such a configuration is attained, its general structure and shape will be conserved despite the continuous transformations between several, essentially equivalent configurations."
Dai, Q., Zhu, Y., & Jiang, Q. (2013), Electronic and Magnetic Engineering in Zigzag Graphene Nanoribbons having a Topological Line Defect at Different Positions with or without Strain. The Journal of Physical Chemistry C, 117: 4791-4799, doi: 10.1021/jp3068987, Citation: "Diffusion, coalescence, and reconstruction of these nonhexagonal rings have been studied by both theoretical and experimental techniques. In addition to the point defects, the extended line defect (LD) composed of alternating pentagon-heptagon (5−7) structure has also been observed during chemical vapor deposition growth on Cu substrate."
Kaiser, U. A. (2013) Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope, PDF, Citation: "We discuss how grain boundaries migrate on the atom-by-atom base."
Komsa, H. P., Kurasch, S., Lethinen, O., Kaiser, U., & Krasheninnikov, A. V. (2013), From point to extended defects in two-dimensional MoS2: Evolution of atomic structure under electron irradiation. Physical Review B, 88: 035301, doi: 10.1103/PhysRevB.88.035301, Citation: "It has been found that prolonged electron irradiation may give rise to the development of new morphologies in a 2D sample, such as "flower" defects in graphene."
Lee, G. D., Yoon, E., Wang, C. Z., & Ho, K. M. (2013). Atomistic processes of grain boundary motion and annihilation in graphene. Journal of Physics: Condensed Matter, 25: 155301, doi: 10.1088/0953-8984/25/15/155301, Citation: "Recently, the motion of a GB has been reported in a TEM experiment. SW transformation was considered."
Lehtinen, O., Kurasch, S., Krasheninnikov, A. V., & Kaiser, U. (2013). Atomic scale study of the life cycle of a dislocation in graphene from birth to annihilation. Nature communications, 4: 2098, doi: 10.1038/ncomms3098, Citation: "A small closed grain boundary loop (the flower defect) is highl stable under an electron beam."
Robertson, A. W., & Warner, J. H. (2013), Atomic resolution imaging of graphene by transmission electron microscopy. Nanoscale, 5: 4079-4093, doi: 10.1039/C3NR00934C, Citation: "The real-time observation of grain boundary migration is achievable by AC-TEM; by exploiting the propensity for SW bond rotations at electron irradiation energies of 80 kV it is possible to induce changes in grain boundaries at an appreciable rate, and thus it is possible to witness the collapse of isolated nanometre scale grain boundary loop structures, such as that shown in this [Figure], to pristine lattice with no angular misorinetation."
Rozada, R., Paredes, J. I., Villar-Rodil, S., Martínez-Alonso, A., & Tascon, J. M. (2013), Towards full repair of defects in reduced graphene oxide films by two-step graphitization. Nano Research, 6: 216-233, doi: 10.1007/s12274-013-0298-6, Citation: "In its low energy configuration, this type of line defect is thought to be made up of a string of alternating pentagons and heptagons. Since we cannot expect the annihilation of the grain boundaries even at graphitization temperatures higher than those employed here, a different approach must be adopted."
Tuan, D. V., Kotakoski, J., Louvet, T., Ortmann, F., Meyer, J. C., & Roche, S. (2013), Scaling Properties of Charge Transport in Polycrystalline Graphene. Nano letters, 13: 1730-1735, doi: 10.1021/nl400321r, Citation: "Experimental studies have observed the complex forms of GB structures (not restricted to infinite linear arrangements of dislocation cores). Our models for polycrystalline graphene resemble experimentally observed structures: atomic-resolution and diffraction-filtered electron microscopy experiments have revealed that the grains stitch together predominantly via pentagon−heptagon pairs."
Wu, J., & Wei, Y. (2013), Grain misorientation and grain-boundary rotation dependent mechanical properties in polycrystalline graphene. Journal of the Mechanics and Physics of Solids, 61: 1421-1432, doi: 10.1016/j.jmps.2013.01.008, Citation: "Graphene is composed of a series of disclination dipoles. Analogy to dislocations, disclination dipoles interact with other dipoles and may migrate as well under thermal or mechanical undulations."
Ago, H., Ogawa, Y., Tsuji, M., Mizuno, S., & Hibino, H. (2012), Catalytic Growth of Graphene: Toward Large-Area Single-Crystalline Graphene. Journal of Physical Chemistry Letters, 3: 2228-2236, doi: 10.1021/jz3007029, Citation: "Such atomic-scale investigation allows us to study dynamic phenomena, such as migration of domain boundaries, as reported very recently."
Robertson, A. W., Allen, C. S., Wu, Y. A., He, K., Olivier, J., Neethling, J., Kirkland, A. I., & Warner, J. H. (2012), Spatial control of defect creation in graphene at the nanoscale. Nature Communications, 3: 1144, doi: 10.1038/ncomms2141, Citation: "Kurasch et al. showed that these closed-looped structures can unwind under higher beam current densityies of 107 e−1 nm−2 s−1."
Wang, Z.(1,2), Zhou, Y. G.(2), Bang, J.(3), Prange, M. P.(2), Zhang, S. B.(3), & Gao, F.(2) (2012), Modification of Defect Structures in Graphene by Electron Irradiation: ab initio Molecular Dynamics Simulations. The Journal of Physical Chemistry C, 116: 16070-16079, doi: , Citation: "The mechanism of the GBs motion through sequential bond rations in graphene has been confirmed by the aberration-corrected high-resolution transmission electron microscopy."
Lechner, L., Biskupek, J., & Kaiser, U. A. (2012). Improved Focused Ion Beam Target Preparation of (S)TEM Specimen — A Method for Obtaining Ultrathin Lamellae. Microscopy and Microanalysis, 18:, 379–384. doi: 10.1017/S1431927611012499
Lee, Z., Meyer, J. C., Rose, H., & Kaiser, U. (2012), Optimum HRTEM image contrast at 20 kV and 80 kV - Exemplified by graphene. Ultramicroscopy, 112: 39-46, doi: 10.1016/j.ultramic.2011.10.009. Cited by (15)
Borrnert, F., Bachmatiuk, A., Gorantla, S., Wolf, D., Lubk, A., Buchner, B., & Rummeli, M. H. (2013), Retro-fitting an older (S) TEM with two Cs aberration correctors for 80 kV and 60 kV operation. Journal of microscopy, 249: 87-92, doi: 10.1111/j.1365-2818.2012.03684.x, Citation: "[Figure] shows an intensity profile along a line of single-layer graphene. The contrast is about 5% which is in good agreement with that found by Lee at al. for imaging graphene using an 80 kV electron acceleration voltage near zero defocus."
Kaiser, U. A. (2013) Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope, PDF, Citation: "The atomic structure and electronic properties of graphene and other low-dimensional objects are obtained by analytical low-voltage aberration-corrected high-resolution transmission electron microscopy."
Lee, Z., Rose, H., Hambach, R., & Kaiser, U. EFTEM image calculation based on mutual coherence approach., EMC2012, doi: PDF, Citation: "When the accelerating voltage is decreased to as low as 20 kV, all objects are strong scatterers."
Lichte, H., Börrnert, F., Lenk, A., Lubk, A., Röder, F., Sickmann, J., Sturm, S., Vogel, K., & Wolf, D. (2013). Electron Holography for fields in solids: Problems and progress. Ultramicroscopy, In Press, doi: 10.1016/j.ultramic.2013.05.014, Citation: "Dynamical diffraction and back-scattering effects get stronger and the phase object approximation may not hold."
Robertson, A. W., & Warner, J. H. (2013), Atomic resolution imaging of graphene by transmission electron microscopy. Nanoscale, 5: 4079-4093, doi: 10.1039/C3NR00934C, Citation: "The weak-phase object approximation is known to break down for extremely low accelerating voltages (20 kV), due to the increased interaction between the electron beam and carbon atoms."
Shevitski, B., Mecklenburg, M., Hubbard, W. A., White, E. R., Dawson, B., Lodge, M. S., Ishigami, M. & Regan, B. C. (2013), Dark-field transmission electron microscopy and the Debye-Waller factor of graphene. Physical Review B, 87: 045417, doi: 10.1103/PhysRevB.87.045417, Citations: "The Debye-Waller analysis presented here (and extending the diffraction calculation to give electron intensities in an image plane) might also shed light on the Stobbs factor contrast discrepancy between HRTEM experiment and simulation."
Yoshida, K., & Sasaki, Y. (2013), Optimal accelerating voltage for HRTEM imaging of zeolite. Microscopy, 62: 369-375, doi: 10.1093/jmicro/dfs087, Citation: "Besides, taking the electron sensitivity of image contrast into consideration the influence of the accelerating voltage on HRTEM imaging is more complicated."
Young, R. J. (2013), Two-Dimensional Nanocrystals: Structure, Properties and Applications. Arabian Journal for Science and Engineering, 38: 1289-1304, doi: 10.1007/s13369-013-0618-x, Citation: "The atomic structure of graphene can be imaged directly using transmission electron microscopy (TEM)."
Zhang, B., Zhang, W., Shao, L., & Su, D. S. (2013), Optimum Energy-Dispersive X-Ray Spectroscopy Elemental Mapping for Advanced Catalytic Materials. ChemCatChem, Early View, doi: 10.1002/cctc.201200654, Citation: "Another sample was investigated herein to confirm that high-quality elemental maps could be obtained by selecting suitable electron doses and dwell times, even for electronbeam-sensitive materials, such as nitrogen-doped graphene oxide (GO) whose microanalysis is usually necessarily conducted at 80 kV instead of the routine 200 kV."
Biskupek, J., P. Hartel, M. Haider, U. A. Kaiser (2012), Effects of residual aberrations explored on single-walled carbon nanotubes. Ultramicroscopy, 116: 1-7, doi: 10.1016/j.ultramic.2012.03.008, Citations: "Carbon nanostructures can also serve as an ideal test object to judge the optical performance of the microscope for several reasons: These nanostructures are (almost) 2D objects with a well defined thickness of one atomic layer (graphene) or two atomic layers in projection (SWNTs). Therefore neither accurate specimen orientation nor dynamic effects have to be considered even at voltages of 80 kV."
Hayashi, T., Muramatsu, H., Shimamoto, D., Fujisawa, K., Tojo, T., Muramoto, Y., Yokomae T., Asaoka T., Kim Y. A., Terrones M., & Endo M. (2012), Determination of the stacking order of curved few-layered graphene systems. Nanoscale, 4: 6419-6424, doi: 10.1039/C2NR30883E, Citation: "The defocus conditions should be near optimal to obtain a good FFT image, but slight change of defocus will not greatly affect the final result."
Kaiser, U. A. Low-voltage TEM-current status and future prospects. EMC 2012, PDF, Citation: "We demonstrate by means of image calculations that at 20 kV the contrast, even for graphene, a one-carbon-atom-thin material, cannot be described by means of the weak phase-object approximation, and that correction of chromatic aberration is a prerequisite for obtaining high-resolution, high-contrast zero-loss and energy-filtered inelastic images."
Lee, Z., Rose, H., Hambach, R., & Kaiser, U. A. (2012) EFTEM image calculation based on mutual coherence approach. EMC2012, doi: PDF, Citation: "The conventional image simulations consider take elastic scattering, which suffices at medium voltages for most objects. However, because at 20 kV all atoms are strong scatters, we must incorporate the effect of inelastic scattering in the image calculation."
Linck, M. (2012), Optimum Aberration Coefficients for Recording High-Resolution Off-Axis Holograms in a Cs-corrected TEM. Ultramicroscopy, 124: 77-87, doi: 10.1016/j.ultramic.2012.08.006, Citation: "In the thickness range from about 4nm - 10nm, a stripeshape occurs inthe C1-C3-map of the standard deviation of the object phase. This behavior can be attributed to periodically repeating lattice plane contrast with changing defocus. This effect is well-known from HRTEM imaging."
Young, R. J., Kinloch, I. A., Gong, L., & Novoselov, K. S. (2012), The mechanics of graphene nanocomposites: A review. Composites Science and Technology, 72: 1459-1476, doi: 10.1016/j.compscitech.2012.05.005, Citation: "The atomic structure of graphene can be observed directly using transmission electron microscopy (TEM)."
Lee, Z., Rose, H., Hambach, R., & Kaiser, U. (2012). EFTEM image calculation based on mutual coherence approach. In EMC 2012 15th European Microscopy Congress 16-21 September 2012, Manchester, United Kingdom, 2 pages.
Li, X. H., Kurasch, S., Kaiser, U., & Antonietti, M. (2012), Synthesis of Monolayer-Patched Graphene from Glucose. Angewandte Chemie International Edition, 51: 9689-9692, doi: 10.1002/anie.201203207. Cited by (2)
Qihua, Y., Su, P., Xiao, H., Zhao, J., Yao, Y., Shao, Z. G., & Li, C. (2013), NCNTs Derived from Zn-Fe-ZIF Nanospheres and Their Application as Efficient Oxygen Reduction Electrocatalysts with in-situ Generated Iron Species. Chemical Science, 4: 2941-2946, doi: 10.1039/C3SC51052B, Citation: "."
Trendbericht (2013), Organische Chemie 2012. (only in German) Nachrichten aus der Chemie, 61: 265-297, doi: 10.1002/nadc.201390087, Citation: "Different concepts were pursued to produce graphene-like materials. Li et al. presented an elegant method for the synthesis of graphene flakes ranging in size from 10 to 100 microns from very low-cost and easily available glucose."
Meyer, J. C., F. Eder, S. Kurasch, V. Skakalova, J. Kotakoski, H.-J. Park, S. Roth, A. Chuvilin, S. Eyhusen, G. Benner, A. V. Krasheninnikov, U. A. Kaiser (2012), Accurate Measurement of Electron Beam Induced Displacement Cross Sections for Single-Layer Graphene. Phys. Rev. Lett., 108: 196102, doi: 10.1103/PhysRevLett.108.196102. Cited by (39)
Berseneva, N., Gulans, A., Krasheninnikov, A. V., & Nieminen, R. M. (2013), Electronic structure of boron nitride sheets doped with carbon from first-principles calculations. Physical Review B, 87: 035404, doi: 10.1103/PhysRevB.87.035404, Citation: "The effects of temperature on the displacement thresholds, give rise to a tail just below the threshold only and do not change the shapes of the curves at higher voltages."
Bichoutskaia, E., Lebedeva, I., Skowron, S., & Popov, A. (2013). Approaches to modelling irradiation-induced processes in transmission electron microscopy. Nanoscale, 5: 6677-6692, doi: 10.1039/C3NR02130K
Chen, C. T., Casu, E. A., Gajek, M., & Raoux, S. (2013), Ultra-Low Damage High-Throughput Sputter Deposition on Graphene. arXiv preprint, arXiv: 1303.3325, Citation: "To cause damages such as vacancies in graphene during the knock-on collisions, these electrons must transfer sufficient energy to the C atoms to overcome their displacement threshold. The reduced onset energy for emission determined by Meyer 2012, 80 - 100 keV, is beyond the energy scale of the irradiated electrons in any sputtering system.
Chen, X. L., Wang, L., Li, W., Wang, Y., He, Y. H., Wu, Z. F., Han, Y., Zhang, M. W., Xiong, W. & Wang, N. (2013). Negative compressibility observed in graphene containing resonant impurities. Applied Physics Letters, 102: 203103, doi: 10.1063/1.4807394
Cong, C., Li, K., Zhang, X. X., & Yu, T. (2013), Visualization of arrangements of carbon atoms in graphene layers by Raman mapping and atomic-resolution TEM. Scientific reports, 3: 1195, doi: 10.1038/srep01195, Citation: "It is now possible to resolve every single carbon atom by HRTEM with the development of the aberration-corrected, monochromated TEM microscope."
Cretu, O., Botello-Mendez, A. R., Janowska, I., Pham-Huu, C., Charlier, J. C., & Banhart, F. (2013), Electrical conductivity measured in atomic carbon chains. arXiv preprint, arXiv: 1302.5207, Citation: "By assuming a displacement threshold of 14 eV, we calculated a displacement rate of approximately 0.01 s-1 for each carbon atom under the present irradiation conditions."
Hardcastle, T. P., Seabourne, C. R., Zan, R., Brydson, R. M. D., Bangert, U., Ramasse, Q. M., Novoselov, K. S., & Scott, A. J. (2013). Mobile metal adatoms on single layer, bilayer, and trilayer graphene: An ab initio DFT study with van der Waals corrections correlated with electron microscopy data. Physical Review B, 87: 195430, doi: 10.1103/PhysRevB.87.195430, Citation: "A recent quantitative study of beam damage in graphene considered the displacement of atoms during the TEM imaging process."
Hernandez, S. C., Bezares, F. J., Robinson, J. T., Caldwell, J. D., & Walton, S. G. (2013), Controlling the local chemical reactivity of graphene through spatial functionalization. Carbon, 60: 84-93, doi: 10.1016/j.carbon.2013.03.059, Citation: "Concerning the ability to pattern graphene with functional groups, many processes are reductive in nature."
Kaiser, U. A. (2013) Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope, PDF, Citation: "We discuss the determination of knock-on damage thresholds in two-dimensional."
Komsa, H. P., Kurasch, S., Lehtinen, O., Kaiser, U., & Krasheninnikov, A. V. (2013). From point to extended defects in two-dimensional MoS2: Evolution of atomic structure under electron irradiation. Physical Review B, 88: 035301, doi: 10.1103/PhysRevB.88.035301, Citation: "Exposure to the electron beam during imaging can lead to production of defects in the sample, e.g. due to ballistic displacement of atoms. A nonzero probability is already expected for electron energies of 80 keV used in the experiments, when the ionic movement at finite temperatures is accounted for in the cross-section calculation."
Lee, J., Zhou, W., Pennycook, S. J., Idrobo, J. C., & Pantelides, S. T. (2013), Direct visualization of reversible dynamics in a Si6 cluster embedded in a graphene pore. Nature communications, 4: 1650, doi: 10.1038/ncomms2671, Citation: "Electron-beam-induced ejection of carbon atoms and defect creation/migration has been actively studied in graphene and carbon nanotubes."
Lehtinen, O., Kurasch, S., Krasheninnikov, A. V., & Kaiser, U. (2013). Atomic scale study of the life cycle of a dislocation in graphene from birth to annihilation. Nature Communications, 4: 2098, doi: 10.1038/ncomms3098, Citation: "In our experiment, we used an operating voltage of 80 kV, which is below the static sputtering threshold in graphene. However, thermal vibrations lead to non-zero displacement cross-section and therefore allow occasional sputtering."
Meyer, J. (2013), New horizons and challenges in the microscopic characterization of 2-D materials, PDF, Citation: "The study of nano-carbons and other low-atomic number materials remains a particular challenge for high resolution transmission electron microscopy (HRTEM) owing to their intrinsically low contrast and high susceptibility to radiation damage. However, the recent developments in aberration-corrected electron optics open a route to a atomically-resolved studies of these materials at reduced electron energies below the knock-on threshold of carbon atoms in graphene."
Morandi, V., Ortolani, L., Migliori, A., Cadelano, E., & Colombo, L. (2013). Folds and Buckles at the Nanoscale: Experimental and Theoretical Investigation of the Bending Properties of Graphene Membranes. Topics in Current Chemistry 2013, doi: 10.1007/128_2013_451, Citation: "Among these investigations we can find physical and chemical properties of the systems under analysis."
Murakami, K., Kadowaki, T., & Fujita, J. I. (2013), Damage and strain in single-layer graphene induced by very-low-energy electron-beam irradiation. Applied Physics Letters, 102, 043111, doi: 10.1063/1.4790388, Citation: "There is a report on irradiation-induced damage in graphene."
Ochedowski, O., Marinov, K., Wilbs, G., Keller, G., Scheuschner, N., Severin, D., Bender, M., Maultzsch, J., Tegude, F. J., & Schleberger, M. (2013). Radiation hardness of graphene and MoS2 field effect devices against swift heavy ion irradiation. Journal of Applied Physics, 113: 214306, doi: 10.1063/1.4808460, Citation: "The displacement energy for carbon atoms in the Single Layer Graphene lattice is 22 eV."
Robertson, A. W., & Warner, J. H. (2013), Atomic resolution imaging of graphene by transmission electron microscopy. Nanoscale, 5: 4079-4093, doi: 10.1039/C3NR00934C, Citation: "In the specific case of graphene, imaging at or below an accelerating voltage of 80 kV reduces the knock-on damage suffered by a pristine sheet due to the majority of electrons imparting energy below the minimum sputtering threshold energy of approximately 22 eV. This low voltage still does not prevent electron mediated chemical etching or the sputtering of under-coordinated carbons. Further care needs to be taken with controlling the electron dose rate that an area of graphene receives, with higher dose rates leading to some defect formation even at 80 kV."
Robertson, A. W., Montanari, B., He, K., Kim, J., Allen, C. S., Wu, Y. A., Olivier, J., Neethling, J., Harrison, N., Kirkland, A. I. & Warner, J. H. (2013), Dynamics of Single Fe Atoms in Graphene Vacancies. Nano letters, 13: 1468-1475, doi: 10.1021/nl304495v, Citation: "It is also possible that the highlighted C atom is ejected outright by the electron collision, although the sputtering cross-section for this at 80 kV, at least for a pristine lattice, is unfavorable."
Santana, A., Zobelli, A., Kotakoski, J., Chuvilin, A., & Bichoutskaia, E. (2013), Inclusion of radiation damage dynamics in high-resolution transmission electron microscopy image simulations: The example of graphene. Physical Review B, 87: 094110, doi: 10.1103/PhysRevB.87.094110, Citation: "The cross sections corresponding to ejection of atoms from the flake due to head-on collisions with the imaging electrons can be either precomputed or estimated directly from experiment. The corresponding ejection cross sections were calculated taking into account the role of lattice vibrations."
Shevitski, B., Mecklenburg, M., Hubbard, W. A., White, E. R., Dawson, B., Lodge, M. S., Ishigami, M. & Regan, B. C. (2013), Dark-field transmission electron microscopy and the Debye-Waller factor of graphene. Physical Review B, 87: 045417, doi: 10.1103/PhysRevB.87.045417, Citations: "TEM can resolve atomic-scale defects."
Tao, L., Qiu, C., Yu, F., Yang, H., Chen, M., Wang, G., & Sun, L. (2013). Modification on Single-Layer Graphene Induced by Low-Energy Electron-Beam Irradiation. The Journal of Physical Chemistry C. 117: 10079-10085, doi: 10.1021/jp312075v, Citations: "The direct measurement of knock-on displacement cross sections has been reported."
Waldmann, D., Butz, B., Bauer, S., Englert, J. M., Jobst, J., Ullmann, K., Fromm, Felix, Ammon, M., Enzelberger, M., Hirsch, A., Maier, S., Schmuki, P., Seyller, T., Spiecker, E., & Weber, H. B. (2013). Robust Graphene Membranes in a Silicon Carbide Frame. ACS nano, 7: 4441-4448, doi: 10.1021/nn401037c, Citation: "In particular, high-resolution TEM (HRTEM) is used to study defects, grain boundaries, or the incorporation of dopands into the graphene sheet."
Wang, H. T., Feng, Q., Cheng, Y., Yao, Y., Wang, Q., Li, K., Schwingenschlogl, U., Zhang, X. X., & Yang, W. (2013) Atomic Bonding between Metal and Graphene. The Journal of Physical Chemistry C, 117: 4632-4638, doi: 10.1021/jp311658m, Citation: "To minimize the knock-on damage to graphene, the TEM was operated at 60 kV, corresponding to a maximum transferred energy (11.3 eV) far below the threshold energy (16−17 eV)."
Zhang, B., Mei, L., & Xiao, H. (2012). Nanofracture in graphene under complex mechanical stresses. Applied Physics Letters, 101: 121915, doi: 10.1063/1.4754115, Citation: "An electron beam is a very effective tool for probing the interaction between electrons and carbon atoms on, e.g., graphene."
Zhang, B., Mei, L., & Xiao, H. (2012). Nanofracture in graphene under complex mechanical stresses. Applied Physics Letters, 101: 121915, doi: 10.1063/1.4754115, Citation: "An electron beam is a very effective tool for probing the interaction between electrons and carbon atoms on, e.g., graphene."
Ahlgren, E. H., Kotakoski, J., Lehtinen, O., & Krasheninnikov, A. V. (2012), Ion irradiation tolerance of graphene as studied by atomistic simulations. Applied Physics Letters, 100: 233108, doi: 10.1063/1.4726053, Citation: "The pre-existing vacancies in the structure on average lower the binding energy of the target atoms which makes an important contribution to the sputtering when the transferred energies are very close to the displacement threshold (22 eV in pristine graphene). Moreover, vacancies in graphene tend to partially 'heal' themselves by forming non-hexagonal rings due to bond rotations."
Biskupek, J., P. Hartel, M. Haider, U. A. Kaiser (2012), Effects of residual aberrations explored on single-walled carbon nanotubes. Ultramicroscopy, 116: 1-7, doi: 10.1016/j.ultramic.2012.03.008, Citations: "The knock-on threshold energy for carbon atoms in single-layer graphene was determined to lie between 90 and 95 keV."
Egerton, R. F. (2012), Mechanisms of radiation damage in beam-sensitive specimens, for TEM accelerating voltages between 10 and 300 kV. Microscopy Research and Technique, 75, 1550-1556, doi: 10.1002/jemt.22099, Citation: "Each carbon atom has several bonds and Ed is said to be as high as 22 eV in single-layer graphene. The observed threshold is at about 85 keV and the discrepancy has been explained as being due to out-of-plane (zero-point) vibrations of the C atoms."
Huang, P. Y., Meyer, J. C., & Muller, D. A. (2012), From atoms to grains: Transmission electron microscopy of graphene. MRS bulletin, 37: 1214-1221, doi: 10.1557/mrs.2012.183, Citation: "Graphene can be imaged using electrons below its knock-on damage threshold of smaller than 90 kV to minimize damage to the lattice or above this voltage to induce structural transformations. Along with other radiation-sensitive systems, such as biological samples, graphene has driven the development of low-voltage, high-resolution instruments."
Komsa, H. P., Kotakoski, J., Kurasch, S., Lehtinen, O., Kaiser, U., & Krasheninnikov, A. V. (2012), Two-dimensional transition metal dichalcogenides under electron irradiation: defect production and doping. Physical Review Letters, 109: 035503, doi: 10.1103/PhysRevLett.109.035503, Citation: "An accurate estimation of the displacement cross section requires including the effects of lattice vibrations on the energy transferred from an electron to a target atom. Counting the actual number of sputtered atoms as by Meyer et al. 2012, the cross section for sputtering was found to be 1:8 barn, which is in a reasonable agreement with the calculated cross-section of 0:8 barn, taking into account that the theoretical estimates are very sensitive to inaccuracies in the parameters of the model at energies below the static threshold."
Kotakoski, J., & Meyer, J. C. (2012), Mechanical properties of polycrystalline graphene based on a realistic atomistic model. Physical Review B, 85: 195447, doi: 10.1103/PhysRevB.85.195447, Citation: "We noticed only very rarely if ever four-coordinated atoms which would indicate problems with the interaction model (such coordination is never observed in sp2-bonded graphene even when it is heavily amorphized under an electron beam)."
Krivanek, O. L., Zhou, W., Chisholm, M. F., Idrobo, J. C., Lovejoy, T. C., Ramasse, Q. M., & Dellby, N. (2012), Gentle STEM of single atoms: Low keV imaging and analysis at ultimate detection limits. Low Voltage Electron Microscopy: Principles and Applications, 119-161, doi: 10.1002/9781118498514.ch6, Citation: "Using the 13C isotope instead of regular carbon (12C) has no effect on image contrast, but raises the onset energy for knock-on damage to above 95 keV."
Kurasch, S., J. Kotakoski, O. Lehtinen, V. Skakalova, J. H. Smet, C. Krill III, A. V. Krasheninnikov, & U. A. Kaiser (2012), Atom-by-Atom Observation of Grain Boundary Migration in Graphene. Nano Lett., 12: 3168-3173, doi: 10.1021/nl301141g, Citation: "Knock-on sputtering of three-coordinated carbon atoms becomes significant only at slightly higher voltages, as is extensively explained in. Correspondingly, hole growth in graphene under 80 kV electron irradiation is driven by chemical effects, not knock-on displacements."
Ramasse, Q. M., Seabourne, C. R., Kepaptsoglou, D. M., Zan, R., Bangert, U., & Scott, A. (2012), Probing the bonding and electronic structure of single atom dopants in graphene with electron energy loss spectroscopy. Nano letters, doi: 10.1021/nl304187e, Citations: "Frequent atomic rearrangement was observed in these areas; although the 60 keV primary energy of the beam is below the knock-on threshold for carbon."
Robertson, A. W., Allen, C. S., Wu, Y. A., He, K., Olivier, J., Neethling, J., Kirkland, A. I., & Warner, J. H. (2012), Spatial control of defect creation in graphene at the nanoscale. Nature Communications, 3: 1144, doi: 10.1038/ncomms2141, Citation: "Meyer et al. 2012 studied the electron beam dependent cross-section for sputtering in graphene using a BCD of at most 10^6 e−1nm−2s−1, and at 80 kV they did not observe a single defect for a total dose of up to 10^10e−1nm−2. We measured a cross-section of 1.35×10^−2barn for a BCD ~10^8e−1nm−2s−1, which is more than two orders of magnitude larger than the calculated value of 7×10−5 barn reported in Meyer et al. 2012. This confirms that standard knock-on sputtering cannot be the mechanism in our observations."
Susi, T., Kotakoski, J., Arenal, R., Kurasch, S., Jiang, H., Skakalova, V., Stephan, O., Krasheninnikov, A. V., Kauppinen, E. I., Kaiser, U. A., & Meyer, J. C. (2012), Atomistic Description of Electron Beam Damage in Nitrogen-Doped Graphene and Single-Walled Carbon Nanotubes. ACS nano, 6: 8837-8846, doi: 10.1021/nn303944f, Citation: "Although electron beam effects in undoped sp2-bonded carbon structures have been studied for decades, quantitative analysis on a single-atom level became possible only recently. Earlier estimates were based on atomistic simulations with only qualitative comparisons to experiments, complicated by the fact that different computational methods yielded differing results. Moreover, most simulations gave displacement threshold values higher than experimental estimates, a result attributed to effects associated with electronic excitations neglected in simulations. A direct comparison between accurate experiments and simulations solved this discrepancy in the case of graphene. It turned out that lattice vibrations must be taken into account when estimating the displacement cross sections from simulated threshold energies. When this was done, electron irradiation-induced damage in graphene could be completely described by elastic knock-on collisions between the electrons and target atoms in graphene, which lead to atomic displacements with a cross section approximated utilizing the McKinley Feshbach formula. An excellent agreement was reached with experimental results and simulations without any fitted parameters. This is in line with an earlier estimate that, for example, heating caused by the electron beam during a typical experiment has only a negligible effect on a graphenic target material. The results revised the old assumption of a sharp threshold at acceleration voltages slightly above 80 kV (for sp2-bonded carbon structures) after which atomic displacements become possible with a smooth onset between ∼80 and 110 kV. Moreover, the damage in pristine tubes tends to appear at sites with visible adsorbants (Figure), which suggests an active chemical etching process."
Van Tuan, D., Kumar, A., Roche, S., Ortmann, F., Thorpe, M. F., & Ordejon, P. (2012), Insulating behavior of an amorphous graphene membrane. Physical Review B, 86: 121408, doi: 10.1103/PhysRevB.86.121408, Citation: "Beyond individual defects and polycrystallinity, a higher level of disorder can be induced on graphene to the point of obtaining two-dimensional fully amorphous networks composed of sp2 hybridized carbon atoms. Such networks contain rings other than hexagons in a disordered arrangement. The average ring size is six according to Euler’s theorem, allowing these systems to exist as flat 2D structures. Experimentally, such amorphous two-dimensional lattices have been obtained in electron-beam irradiation experiments, and directly visualized by high resolution electron transmission microscopy."
Wang, Z.(1,2), Zhou, Y. G.(2), Bang, J.(3), Prange, M. P.(2), Zhang, S. B.(3), & Gao, F.(2) (2012), Modification of Defect Structures in Graphene by Electron Irradiation: ab initio Molecular Dynamics Simulations. The Journal of Physical Chemistry C, 116: 16070-16079, doi: , Citation: "Fortunately, the electron threshold energy in graphene can be accurately measured, and an accurate estimation of the displacement cross section requires including the effects of lattice vibrations on the energy transferred from an electron to a target atom."
Zhang, B., Mei, L., & Xiao, H. (2012), Nanofracture in graphene under complex mechanical stresses. Applied Physics Letters, 101, 121915, doi: 10.1063/1.4754115, Citation: "Radiation damage by electron-beam energy and applied dose cannot be neglected for light element materials due to the limitations of HRTEM."
Moorthy, S. K. E., Biskupek, J., Mierlo, W. Van, & Bernhard, J. (2012). Electron microscopic characterization of Li-O2 batteries: Clean, green electrochemical energy storage. In EMC 2012 15th European Microscopy Congress 16-21 September 2012, Manchester, United Kingdom, 2 pages.
Pantelic, R. S., Meyer, J. C., Kaiser, U., & Stahlberg, H. (2012), The application of Graphene as a sample support in Transmission Electron Microscopy. Solid State Communications, 152: 1375-1382, doi: 10.1016/j.ssc.2012.04.038. Cited by (5)
Dyson, M. A., Sanchez, A. M., Patterson, J. P., O'Reilly, R. K., Sloan, J., & Wilson, N. R. (2013), A new approach to high resolution, high contrast electron microscopy of macromolecular block copolymer assemblies. Soft Matter, 9: 3741-3749, doi: 10.1039/c3sm27787a, Citation: "Pantelic et al. 2012 have shown that due to their greater crystallinity and lower scattering cross-section graphene supports outperform even GO supports, and demonstrated their application through imaging the periodic structure of the tobacco mosaic virus."
Koh, A. L., Gidcumb, E., Zhou, O., & Sinclair, R. (2013). Observations of Carbon Nanotube Oxidation in an Aberration-Corrected Environmental Transmission Electron Microscope. ACS nano, 7: 2566-2572, doi: 10.1021/nn305949h, Citation: "Heating to at least 300 °C in the electron microscope prior to beam exposure is an effective way of removing contaminants present on CVD-grown carbonaceous material."
Panthani, M. G., Hessel, C. M., Reid, D., Casillas, G., Jose-Yacaman, M., & Korgel, B. A. (2013), Graphene-Supported High-Resolution TEM and STEM Imaging of Silicon Nanocrystals and their Capping Ligands. Journal of Physical Chemistry C, 116, 22463-22468, doi: 10.1021/jp308545q, Citation: "Graphene, atomically thin and smooth carbon, is the ultimate support for electron microscopy and has been used to obtain images of molecular and nanoscale objects with unprecedented clarity."
Robertson, A. W., & Warner, J. H. (2013), Atomic resolution imaging of graphene by transmission electron microscopy. Nanoscale, 5: 4079-4093, doi: 10.1039/C3NR00934C, Citation: "With the successful isolation of few-layer graphene sheets it became possible to prepare almost ideal electron microscopy samples, permitting the high-resolution imaging of material on the graphene surface."
Zhang, H., Gruner, G., & Zhao, Y. (2013), Recent advancements of graphene in biomedicine. Journal of Materials Chemistry B, 20: 2542-2567, doi: 10.1039/C3TB20405G, Citation: "Owing to particular structures and biocompatible properties, graphene-based hybrid materials were also deemed as an excellent platform for both bioimaging and bioanalysis."
Susi, T., J. Kotakoski, R. Arenal, S. Kurasch, H. Jiang, V. Skakalova, O. Stephan, A. V. Krasheninnikov, E. I. Kauppinen, U. A. Kaiser & J. C. Meyer (2012), Atomistic Description of Electron Beam Damage in Nitrogen-Doped Graphene and Single-Walled Carbon Nanotubes. ACS Nano, 6: 8837-8846, doi: 10.1021/nn303944f. Cited by (7)
Audiffred, M., Elías, A. L., Gutiérrez, H. R., López-Urías, F., Terrones, H., Merino, G., & Terrones, M. (2013), Nitrogen–Silicon Heterodoping of Carbon Nanotubes. Journal of Physical Chemistry C, 117: 8481-8490, doi: 10.1021/jp312427z, Citation: "."
Berseneva, N., Gulans, A., Krasheninnikov, A. V., & Nieminen, R. M. (2013), Electronic structure of boron nitride sheets doped with carbon from first-principles calculations. Physical Review B, 87: 035404, doi: 10.1103/PhysRevB.87.035404, Citation: "We neglected the effects of temperature on the displacement thresholds, as they give rise to a tail just below the threshold only and do not change the shapes of the curves at higher voltages."
Bichoutskaia, E., Lebedeva, I., Skowron, S., & Popov, A. (2013), Approaches to modelling irradiation-induced processes in transmission electron microscopy. Nanoscale, In Press, doi: 10.1039/C3NR02130K, Citation: "Electron irradiation-induced processes in HRTEM have attracted considerable interest in recent decades; these include the creation of single vacancies and other atomic scale defects, and the transformation of carbon, e.g., reported by Susi et al. 2012."
El-Barbary, A. A., Eid, K. M., Kamel, M. A., & Hassan, M. M. (2013), Band gap engineering in short heteronanotube segments via monovacancy defects. Computational Materials Science, 69: 87-94, doi: 10.1016/j.commatsci.2012.10.035, Citation: "This finding is consistent with the current experimentally study of the preference for knock-out of carbon atoms neighbouring substitutional nitrogen atoms in nitrogen doped graphene."
Koh, A. L., Gidcumb, E., Zhou, O., & Sinclair, R. (2013), Observations of Carbon Nanotube Oxidation in an Aberration-Corrected Environmental Transmission Electron Microscope. ACS nano, 7: 2566-2572., doi: 10.1021/nn305949hf, Citation: "The electron dose reported to damage single-wall carbon nanotubes at 80 kV and under a microscope vacuum of 6.5 x 10-8 mbar is about 107 e-/Å2."
Liu, A. C. Y., Arenal, R., & Montagnac, G. (2013), In situ transmission electron microscopy observation of keV-ion irradiation of single-walled carbon and boron nitride nanotubes. Carbon, In Press, doi: 10.1016/j.carbon.2013.05.062, Citation: "."
Robertson, A. W., & Warner, J. H. (2013), Atomic resolution imaging of graphene by transmission electron microscopy. Nanoscale, 5: 4079-4093, doi: 10.1039/C3NR00934C, Citation: "The effect of electron irradiation on TEM specimens is an important consideration when imaging, particularly for samples comprised of light elements such as carbon. Whilst irradiation effects are typically a hindrance with regards to obtaining high quality images, it also presents a potential opportunity for engineering the properties of materials on the nanoscale."
Wu, Y., Eisele, K., Doroshenko, M., Algara-Siller, G., Kaiser, U., Koynov, K., & Weil, T. (2012), A Quantum Dot Photoswitch for DNA Detection, Gene Transfection, and Live-Cell Imaging. Small, 8: 3465-3475, doi: 10.1002/smll.201200409. Cited by (3)
Kuan, S. L., Wu, Y., & Weil, T. (2013), Precision Biopolymers from Protein Precursors for Biomedical Applications. Macromolecular rapid communications, 34: 380-392, doi: 10.1002/marc.201200662, Citation: "It is known that polydentate ligands can stabilize the surface of QDs more effi ciently due to reduced ligand loss."
Walther, A., Schacher, F. H., & Kuhne, A. (2013), Makromolekulare Chemie 2012. Nachrichten aus der Chemie, 61: 330-344, doi: 10.1002/nadc.201390091, Citation: "Weil, Kaiser und Mitarbeiter beschrieben ein multifunktionales System zur Gentransfektion, DNA-Detektion und Lebendzellbildgebung. Dazu nutzten sie Quantenpunkte, auf die ein hydrophiles PEG-Polypeptid-Copolymer aufgepfropft wurde. Die Fluoreszenz der Quantenpunkte wird gequencht, sobald sich DNA in die hydrophile Schale einlagert, und das System eignet sich so als Sonde fur die oben genannten Anwendungen. Die Cytotoxizitat der schwermetallbasierten CdSe- oder CdZnS-Quantenpunkte konnte durch die hydrophile Polymerhülle auf ein Minimum reduziert werden."
Wang, J., Huang, X., Ruan, L., Lan, T., & Ren, J. (2013), Size exclusion chromatography as a universal method for the purification of quantum dots bioconjugates. Electrophoresis, 34: 1764-1771, doi: 10.1002/elps.201200649, Citation: "Approaches for purification of quantum dots bioconjugates are based, for example, on ultrafiltration."
Zoberbier, T., T. W. Chamberlain, J. Biskupek, N. Kuganathan, E. Bichoutskaia, S. Eyhusen, U. A. Kaiser, A. N. Khlobystov (2012), Interactions and Reactions of Transition Metal Clusters with the Interior of Single-Walled Carbon Nanotubes Imaged at the Atomic Scale. J. Am. Chem. Soc., 134: 3073-3079, doi: 10.1021/ja208746z. Cited by (11)
Bichoutskaia, E., Lebedeva, I., Skowron, S., & Popov, A. (2013). Approaches to modelling irradiation-induced processes in transmission electron microscopy. Nanoscale, 5: 6677-6692, doi: 10.1039/C3NR02130K
Ding, M., Tang, Y., & Star, A. (2013), Understanding Interfaces in Metal-Graphitic Hybrid Nanostructures. Journal of Physical Chemistry Letters, 4: 147-160, doi: 10.1021/jz301711a, Citation: "Aberration-corrected HR-TEM (AC-HRTEM) offered effective characterization of the metal−graphitic interface even when MNPs were formed inside of CNTs."
Garg, S., Singla, M., & Singh, S. Metal encapsulated carbon nanotubes: A review, Citation: "Zoberbier et al. revealed the different chemical reactivity and bonding of different encapsulated metals in the order W < Re < Os toward the nanotube at same electron beam energy, besides the shape and size of the filled metal nanoclusters."
Kharlamova, M. V., Yashina, L. V., & Lukashin, A. V. (2013). Comparison of modification of electronic properties of single-walled carbon nanotubes filled with metal halogenide, chalcogenide, and pure metal. Applied Physics A, 112: 297-304, doi: 10.1007/s00339-013-7808-y, Citation: "It has been shown that the internal channels of single-walled carbon nanotubes can be filled with substances of different chemical nature, e.g., including metals."
Santana, A., Zobelli, A., Kotakoski, J., Chuvilin, A., & Bichoutskaia, E. (2013), Inclusion of radiation damage dynamics in high-resolution transmission electron microscopy image simulations: The example of graphene. Physical Review B, 87: 094110, doi: 10.1103/PhysRevB.87.094110, Citation: "Recent advances in electron microscopy, in particular implementation of aberration correction of electromagnetic lenses, have stimulated unprecedented growth of interest in low-voltage high-resolution transmission electron microscopy (HRTEM) capable of spatial resolution at the atomic level when using energy of the imaging electrons near or below the ejection threshold. Many practically useful materials have been studied using HRTEM with great emphasis on carbon nanostructures. The ability of HRTEM to observe the dynamics of individual atoms under the controlled influence of the electron beam (e-beam) brings another dimension to the method potentially providing a tool for direct measurements of diffusion coefficients, cross sections of the damage events, chemical constants, and other characteristics of the dynamic processes that take place at the atomic scale."
Su, D. S., Perathoner, S., & Centi, G. (2013). Nanocarbons for the Development of Advanced Catalysts. Chemical reviews, In Press, doi: 10.1021/cr300367d, Citation: "Zoberbier et al. have demonstrated that clusters of transition metals (W, Re, and Os), upon encapsulation within a single-walled carbon nanotube (SWNT), exhibit marked differences in their affinity and reactivity."
Habenicht, B. F., & Prezhdo, O. V. (2012), ab initio Time-Domain Study of the Triplet State in a Semiconducting Carbon Nanotube: Intersystem Crossing, Phosphorescence Time, and Line Width. Journal of the American Chemical Society, 134: 15648-15651, doi: 10.1021/ja305685v, Citation: "The observed low quantum yields of photoluminescence present a great practical difficulty in numerous CNT applications."
Ilie, A., Crampin, S., Karlsson, L., & Wilson, M. (2012), Repair and stabilization in confined nanoscale systems—inorganic nanowires within single-walled carbon nanotubes. Nano Research, 5: 833-844, doi: 10.1007/s12274-012-0267-5, Citation: "When nanotubes are filled, the inner surface of the nanotube template can engage in chemical reactions and dynamic processes initiated or catalysed by the filling. Whether such phenomena occur or not depends on the bonding energy of the filling species with the nanotube inner wall. In this context, it is not unreasonable to expect some interplay between the structural evolutions of the inner nanowire and the nanotube sheath, manifesting in both destructive and restorative processes. A strong reduction of the van der Waals spacing can be achieved only through bonding of the filling atom with the nanotube inner wall making the return of the atom to the ribbon highly unlikely; a similar decrease in the van der Waals spacing was observed in the binding of an encapsulated transition metal atom to the nanotube inner surface, which was then shown to be a pathway towards tube wall breakage and atom exit (followed by a complete nanotube sectioning)."
Su, D. S., Perathoner, S., & Centi, G. (2012), Catalysis on nano-carbon materials: Going where to? Catalysis Today, 186: 1-6, doi: 10.1016/j.cattod.2012.04.002, Citation: "Zoberbier et al. have demonstrated that clusters of transition metals (W, Re, and Os), upon encapsulation within SWNT exhibit marked differences in their affinity and reactivity."
Takahashi, K., Isobe, S., & Ohnuki, S. (2012), The structural and electronic properties of small osmium clusters (2-14): A density functional theory study. Chemical Physics Letters, 555: 26-30, doi: 10.1016/j.cplett.2012.10.055, Citation: "Small Os clusters have also been reported to be good catalysts in many applications due to their unusual chemistry. Recent, it has also been reported that small Os clusters are extremely reactive with single-walled carbon nanotube in comparison to other transition metal clusters."
Xie, S., Tsunoyama, H., Kurashige, W., Negishi, Y., & Tsukuda, T. (2012), Enhancement in Aerobic Alcohol Oxidation Catalysis of Au25 Clusters by Single Pd Atom Doping. ACS Catalysis, 2: 1519-1523, doi: 10.1021/cs300252g, Citation: "However, to answer the effect of Pd doping, the structures of Au25/CNT and Pd1Au24/CNT must be investigated in more detail using spectroscopic and microscopic tools, such as an aberration-corrected scanning transmission electron microscope."
Zoberbier, T., Biskupek, J., Kaiser, U., Chamberlain, T. W., Bichoutskaia, E., Kuganathan, N., & Khlobystov, A. N. (2012). In-situ low voltage HRTEM studies of single-walled carbon nanotube- interactions with transition (d-element) metal clusters. In EMC 2012 15th European Microscopy Congress 16-21 September 2012, Manchester, United Kingdom, 2 pages.
2011
Chamberlain T. W. , J. C. Meyer, J. Biskupek, J. Leschner, A. Santana, N. A. Besley, E. Bichoutskaia, U. A. Kaiser, A. N. Khlobystov (2011), Reactions of the inner surface of carbon nanotubes and nanoprotrusion processes imaged at the atomic scale. Nature Chemistry, 3: 732-737, doi: 10.1038/NCHEM.1115. Cited by (17)
Murakami, T., Asai, K., Yamamoto, Y., Kisoda, K., & Itoh, C. (2013), X-ray irradiation effect of double walled carbon nanotube. European Physical Journal B, 86, doi: 10.1140/epjb/e2013-30591-8, Citation: "120 kV exceeds the knock-on threshold of carbon from SWNT."
Nakamura, E. (2013), Movies of Molecular Motions and Reactions: The Single-Molecule, Real-Time Transmission Electron Microscope Imaging Technique. Angewandte Chemie International Edition, 52: 236-252, doi: 10.1002/anie.201205693, Citation: "Another example is noteworthy in the context of electron beam and catalysis: the bond reorganization of CNT by multimetallic clusters."
Pan, X., & Bao, X. (2013) Confinement Effects in Nanosupports. Nanomaterials in Catalysis, Chapter 11: 415-441, doi: 10.1002/9783527656875.ch11, Citation: "Chamberlain et al. demonstrated direct experimental evidence of the interaction of catalytically active rhenium atoms with SWCNTs at ambient temperature from aberration-corrected HRTEM. These atoms readily react with C2 biradicals deriving from fullerenes forming ReC2 species, which bonded with the interior surface of SWCNTs upon irradiation by low energy electron beam. Thus, catalyzed by Re atoms, the structurally perfect inner surface of SWCNT was deformed or ruptured forming a metastable asymmetric nanoprotrusion with an open edge, and finally the nanoprotrusion was closed up via a slow symmetrization process."
Santana, A., Zobelli, A., Kotakoski, J., Chuvilin, A., & Bichoutskaia, E. (2013), Inclusion of radiation damage dynamics in high-resolution transmission electron microscopy image simulations: The example of graphene. Physical Review B, 87: 094110, doi: 10.1103/PhysRevB.87.094110, Citation: "Practically useful materials have been studied using HRTEM with great emphasis on carbon nanostructures."
Spisak, S. N., Sumner, N. J., Zabula, A. V., Filatov, A. S., Rogachev, A. Y., & Petrukhina, M. A. (2013), Tuning Binding of Rubidium Ions to Planar and Curved Negatively Charged π Surfaces. Organometallics, In Press, doi: 10.1021/om4001617, Citation: "These interests moved over the years from small planar arenes to large and curved polyaromatic systems, like nanotubes."
Yang, H., Li, M., Fu, L., Tang, A., & Mann, S. (2013), Controlled Assembly of Sb2S3 Nanoparticles on Silica/Polymer Nanotubes: Insights into the Nature of Hybrid Interfaces. Scientific Reports, 3, doi: 10.1038/srep01336, Citation: "In particular, it was demonstrated in other systems such as the decoration of carbon or silica nanotubes with a wide variety of inorganic nanoparticles, the possibility of preparing hybrid functional nanomaterials via selectively assembling Sb2S3 nanoparticles on the surface of preformed nanotubular templates should provide a range of new opportunities."
Bichoutskaia, E., Liu, Z., Kuganathan, N., Faulques, E., Suenaga, K., Shannon, I. J., & Sloan, J. (2012), High-precision imaging of an encapsulated Lindqvist ion and correlation of its structure and symmetry with quantum chemical calculations. Nanoscale, 4: 1190-1199, doi: 10.1039/C2NR11621A, Citation: "It must also be remarked here that even under 80 kV imaging conditions, some wall carbon defects are expected but the rate of defect formation is very greatly reduced in comparison to the previously employed 300 kV imaging conditions."
Bosson, M., Grudinin, S., Bouju, X., & Redon, S. (2012), Interactive physically-based structural modeling of hydrocarbon systems. Journal of Computational Physics, 231, 2581-2598, doi: 10.1016/j.jcp.2011.12.006, Citation: "Carbon nanotubes with a large variety of defects have already been observed experimentally by high-resolution transmission electron microscopy."
Chamberlain, T. W., Biskupek, J., Rance, G. A., Chuvilin, A., Alexander, T. J., Bichoutskaia, E., Kaiser, U. A., & Khlobystov, A. N. (2012), Size, Structure, and Helical Twist of Graphene Nanoribbons Controlled by Confinement in Carbon Nanotubes. ACS nano, 6: 3943-3953, doi: 10.1021/nn300137j, Citation: "Elements such as hydrogen, oxygen, nitrogen have the potential to terminate the dangling bonds of edge of GNRs."
Coleman, K. S. (2012), Nanotubes. Annual Reports Section "A", 108: 478-492, doi: 10.1039/C2IC90014A, Citation: "Chemical reactions have been shown, and visualised using aberration-corrected high-resolution transmission electron microscopy (TEM), to occur on the inside surface of SWCNTs."
Ilie, A., Crampin, S., Karlsson, L., & Wilson, M. (2012), Repair and stabilization in confined nanoscale systems—inorganic nanowires within single-walled carbon nanotubes. Nano Research, 5: 833-844, doi: 10.1007/s12274-012-0267-5, Citation: "When nanotubes are filled, the inner surface of the nanotube template can engage in chemical reactions and dynamic processes initiated or catalysed by the filling."
Ramanathan, M., S Michael Kilbey, I. I., Ji, Q., Hill, J. P., & Ariga, K. (2012), Materials self-assembly and fabrication in confined spaces. Journal of Materials Chemistry, 22: 10389-10405, doi: 10.1039/C2JM16629A, Citation: "As far as the confinement into the interior of the CNT is concerned, the interior space of the single-walled carbon nanotubes is used for the encapsulation of molecules and ionic liquids for the so-called nano-test tube chemistry."
Souier, T., Santos, S., Gadelrab, K., Al Ghaferi, A., & Chiesa, M. (2012), Identification and quantification of the dissipative mechanisms involved in the radial permanent deformation of carbon nanotubes. Journal of Physics D: Applied Physics, 45: 335402, doi: 10.1088/0022-3727/45/33/335402, Citation: "The study of inelastic interactions with CNTs is of great interest since dissipation could be linked to surface reactivity, chemical affinity."
Trendbericht (2012), Festkorperchemie 2011. (only in German) Nachrichten aus der Chemie, 60: 251-264, doi: 10.1515/nachrchem.2012.60.3.251 (only in German), Citation: "New possibilities of transmission electron microscopy (TEM) were demonstrated. The cited publication is devoted to carbon nanotubes (CNT). This material has recently gained some importance for applications in fuel cells, batteries, and catalysis, although many of the fundamental properties are still far from understood. Chamberlain et al. showed that not only the outer surface of CNTs participates in many chemical reactions, but that the inner surface can be active too. Nanometer-sized protrusions of the CNTs were visualized by aberration corrected high resolution TEM (HRTEM). The nanoprotrusions grow inside of the tube, if a transition metal catalyst is present, and offer perspectives for catalysis."
Zoberbier, T., T. W. Chamberlain, J. Biskupek, N. Kuganathan, E. Bichoutskaia, S. Eyhusen, U. A. Kaiser, A. N. Khlobystov (2012), Interactions and Reactions of Transition Metal Clusters with the Interior of Single-Walled Carbon Nanotubes Imaged at the Atomic Scale. J. Am. Chem. Soc., 134: 3073-3079, doi: 10.1021/ja208746z, Citation: "While conventional spectroscopic methods that integrate over larger volumes (e.g., XPS, Raman, etc.) can be applied for characterizing the bulk physicochemical properties, high-resolution transmission electron microscopy (HRTEM) is now rapidly becoming an excellent local-probe tool for studying chemical reactions in nanotubes by imaging transformations in direct space and real time down to the single-atom level."
Khlobystov, A. N. (2011), Carbon nanotubes: from nano test tube to nano-reactor. ACS nano, 5: 9306-9312, doi: 10.1021/nn204596p, Citation: "Furthermore, the scarcity of endohedral fullerenes (EnMFs) severely limits the encapsulation method to small scales (typically, one to a few milligrams of material). To address this problem, exohedral metallofullerenes (ExMFs) have been successfully introduced as vehicles for the transport and encapsulation of Os and Re ([Figure]) thus providing an alternative to EnMFs. The metal atomsin ExMFs are attached to the surfaces of fullerenes and are hence readily available for catalysis, as demonstrated by in situ HRTEM experiments. Even though the catalytic activity of fullerene complexes inside nanotubes has not yet been explored on the preparative scale, the HRTEM observations of Chamberlain et al. indicate that discrete metal atoms can play an important catalytic role within the confines of the nano-reactor, often dramatically changing the pathways of reactions and leading to the formation of unexpected products. It should be noted, however, that the nanotube interior is not as inert toward metal catalysts as was initially believed. HRTEM observations clearly show that small clusters of La15 or Dy26 can catalyze a rupture of the nanotube container, while individual metal atoms of Re trigger a series of structural transformations in the nanotube sidewall."
Pincak, R., Smotlacha, J., & Pudlak, M. (2011), Electronic properties of disclinated nanostructured cylinders. Nanoscale Systems: Mathematical Modeling, Theory and Applications, 2: 81-95, doi: 10.2478/nsmmt-2013-0005, Citation: "The surface of the nanotubes is usually unreactive, but the change of its structure can be provoked by catalytically active atoms of rhenium inserted into the nanotubes."
Chuvilin A. , E. Bichoutskaia, M. C. Gimenez-Lopez, T. W. Chamberlain, G. A. Rance, N. Kuganathan, J. Biskupek, U. A. Kaiser & A. N. Khlobystov (2011), Self-assembly of a sulphur-terminated graphene nanoribbon within a single-walled carbon nanotube. Nature Materials, 10: 687-692, doi: 10.1038/NMAT3082. Cited by (52)
Autes, G., & Yazyev, O. V. (2013), Engineering Quantum Spin Hall Effect in Graphene Nanoribbons via Edge Functionalization. arXiv preprint, arXiv: 1305.7392, Citation: "The sulphur analogues of such nanostructures have been produced recently by fusing sulfur-rich precursor molecules inside a carbon nanotube matrix through heating or electron beam irradiation."
Cabrera-Sanfelix, P., Arnau, A., & Sanchez-Portal, D. (2013), SAM-like arrangement of thiolated graphene nanoribbons: decoupling the edge state from the metal substrate. Physical Chemistry Chemical Physics, 15: 3233-3242, doi: 10.1039/C2CP43047A, Citation: "An interesting mechanism for GNR formation was demonstrated recently by Chuvilin and co-workers. Very thin ZGNRs were produced by electron irradiation of functionalized fullerenes encapsulated into single wall carbon nanotubes. One interesting feature of these thin GNRs is the presence of sulphur atoms terminating the edges of the ribbons. These sulphur edges are a product of the decomposition and reassembling of the S-containing organic groups that functionalize the encapsulated fullerenes during the electron beam exposure. According to the analysis presented by Chuvilin et al., their ZGNRs were formed just by four polyacetylene-like chains (N = 4, in the notation used below), and have lengths ranging from 7 to 20 nm. The fabrication methods proposed by Chuvilin and co-workers suggest that it is possible to control the width of the ribbons and even their chemical termination when they are synthesized under the right conditions and using the appropriate starting monomers. However, we have observed the formation of longer structures, similar to nanoribbons, in simulations using larger cells. Although the structure of these ribbons departs from that of ideal ZGNRs, they can be essentially regarded as an asymmetric version of those found by Chuvilin et al., also formed after electron irradiation of the appropriate molecular precursors. Furthermore, according the results of Lopez-Bezanilla et al. for BN nanoribbons with sulphur termination, given the half-occupation of the S-px band we could expect the dimerization of the S atoms at the edge and the opening of the gap. However, we have failed to find this dimerized structure in our structural relaxations. This is consistent with the results of Chuvilin et al. that only report a dimerized sulphur edge for the oxidized (positively charged) ribbons."
Chernov, A. I., Fedotov, P. V., Talyzin, A. V., Suarez Lopez, I., Anoshkin, I. V., Nasibulin, A. G., Kauppinen, E. I., & Obraztsova, E. D. (2013). Optical Properties of Graphene Nanoribbons Encapsulated in Single-Walled Carbon Nanotubes. ACS nano, In Press, doi: 10.1021/nn4024152, Citation: "Carbon nanotubes also have been used as nanoscale chemical reactors to synthesize sulfur-terminated nanoribbons using various organic molecules."
de Juan, A., & Perez, E. M. (2013), Getting tubed: Mechanical bond in endohedral derivatives of carbon nanotubes?. Nanoscale, Advanced Article, doi: 10.1039/C3NR01683H, Citation: "Recently, Khlobystov and co-workers have described the synthesis of graphene nanoribbons terminated with sulfuratoms (S-GNRs, [Figure]) from TTF@SWNTs, mixtures of (C60:TTF) @SWNTs and other sulfur-containing fullerene derivatives."
Guclu, A. D., Grabowski, M., & Hawrylak, P. (2013), Electron-electron interactions and topology in the electronic properties of gated graphene nanoribbon rings in Mobius and cylindrical configurations. Physical Review B, 87: 035435, doi: 10.1103/PhysRevB.87.035435, Citation: "Graphene nanoribbons are quasi-one-dimensional structures with electronic properties depending on the angle at which they are cut. On the experimental side, although we are not aware of Mobius graphene nanoribbons with zigzag edges yet, twisted nanoribbons were recently obtained inside carbon nanotubes through electron irradiation of functionalized fullerenes."
Kaiser, U. A. (2013) Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope, PDF, Citation: "We discuss then electron-beam-induced transformation route of different nano-carbon structures."
Kou, L., Tang, C., Frauenheim, T., & Chen, C. (2013), Intrinsic Charge Separation and Tunable Electronic Band Gap of Armchair Graphene Nanoribbons Encapsulated in a Double-Walled Carbon Nanotube. Journal of Physical Chemistry Letters, 4: 1328-1333, doi: 10.1021/jz400037j, Citation: "Recently, a novel carbon hybrid nanocomposite, consisting of a GNR encapsulated inside of a single-walled CNT (GNR@SWCNT), has been synthesized from a random mixture of molecular precursors (fullerene or polycyclic aromatic hydrocarbon molecules) within a SWCNT."
Lee, J., Zhou, W., Pennycook, S. J., Idrobo, J. C., & Pantelides, S. T. (2013), Direct visualization of reversible dynamics in a Si6 cluster embedded in a graphene pore. Nature communications, 4: 1650, doi: 10.1038/ncomms2671, Citation: "Electron-beam-induced ejection of carbon atoms and defect creation/migration has been actively studied in graphene and carbon nanotubes."
Li, R., Hu, T., & Dong, J. (2013), Geometric and electronic structures of sulfur-edge-terminated zigzag edge graphene nanoribbons. Physica E: Low-dimensional Systems and Nanostructures, 49: 76-82, doi: 10.1016/j.physe.2013.02.004, Citation: "It is known that the carbon nanotube provides a well-defined nano-scale cylindrical pore for preparing different kinds of Q1D materials in it, such as narrow graphene ribbons. In such a Q1D confined space, the chemical reactions (including those helped by the catalysts) could be much different from them in the 3D free space. For example, recently, Khlobystov and co-workers have successfully synthesized the sulfur-edge-functionalized ZGNR confined in the SWCNTs, which is the first time to be observed in experiment. But the possible stable structures have not been exactly identified in the experiment. Thus, it is very interesting and important to study this problem theoretically. Moreover, we should mention that the finite S-terminated GNRs found in the experiment are twisted by the repulsion between the nearest sulfur atoms and probably also the constraint from the outer carbon nanotubes, which would not happen for the H-terminated ribbon, i.e., the H-terminated GNR remains flat since H-atom is smaller than C atom."
Mandal, B., Sarkar, S., & Sarkar, P. (2013), Energetics and Electronic Structure of Encapsulated Graphene Nanoribbons in Carbon Nanotube. Journal of Physical Chemistry A, In Press, doi: 10.1021/jp4025359, Citation: "Very recently a novel composite material, structured as graphene nanoribbons encapsulated in carbon nanotubes, known as encapsulated graphene nanoribbons, was synthesized."
Miners, S. A., Rance, G. A., & Khlobystov, A. N. (2013), Regioselective control of aromatic halogenation reactions in carbon nanotube nanoreactors. Chemical Communications, 49: 5586-5588, doi: 10.1039/C3CC42414F, Citation: "Few such reactions have been carried out within carbon nanotubes to date, but notable examples include the formation of linear structures, such as graphene nanoribbons."
Popov, A. A., Yang, S., & Dunsch, L. (2013), Endohedral Fullerenes. Chemical reviews, In Press, doi: 10.1021/cr300297r, Citation: "Irradiation of the derivative by the 80 keV electron beam inside the nanotube resulted first in breaking the attached groups followed by disruption of the fullerene cage and finally in the formation of graphene nanoribbons with sulfur-terminated edges."
Qu, C. Q., Wang, C. Y., Qiao, L., Yu, S. S., & Li, H. B. (2013). Transport properties of chemically functionalized graphene nanoribbon. Chemical Physics Letters, 578: 97-101, doi: 10.1016/j.cplett.2013.05.071, Citation: "Khlobystov and co-workers have reported the sulfur-terminated GNRs both theoretically and experimentally."
Santana, A., Zobelli, A., Kotakoski, J., Chuvilin, A., & Bichoutskaia, E. (2013), Inclusion of radiation damage dynamics in high-resolution transmission electron microscopy image simulations: The example of graphene. Physical Review B, 87: 094110, doi: 10.1103/PhysRevB.87.094110, Citation: "Many practically useful materials have been studied using HRTEM with great emphasis on carbon nanostructures."
Skowron, S. T., Lebedeva, I. V., Popov, A. M., & Bichoutskaia, E. (2013), Approaches to modelling irradiation-induced processes in transmission electron microscopy. Nanoscale, Advance Article, doi: 10.1039/C3NR02130K, Citation: "Electron irradiation-induced processes in HRTEM have attracted considerable interest in recent decades; these include the transformation of carbon nanostructures, leading to the formation of entirely new nano-objects and chemical reactions. If atoms that can saturate dangling bonds at the graphene-like edge are present in the mixture, a graphene nanoribbon forms. Sulphur-terminated graphene nanoribbons (shown in [Figure]) have been obtained in this way through the transformation of fullerenes with attached sulphur-containing groups inside carbon nanotubes. Despite the presence of multiple hetero-elements (H, O, N and S) available for termination of the nanoribbon, sulphur termination was exclusively witnessed. This striking result can be explained by comparing displacement cross-sections of potential terminating atoms under electron irradiation, in this case hydrogen and sulphur. Moreover, at an accelerating voltage of 80 kV, corresponding to experimental conditions, it can be seen that while sulphur will undergo no emission from the nanoribbon, the displacement cross-section of hydrogen is very large."
Sorokin, P., & Chernozatonskii, L. (2013), Graphene-based semiconductor nanostructures. Physics-Uspekhi, 56: 105, doi: 10.3367/UFNe.0183.201302a.0113, Citation: "Chuvilin et al. obtained ultranarrow graphene ribbons, but already with zigzag edges (4-ZGNR) inside `pods' consisting of carbon nanotubes with fullerenes inside them, with attached organic groups and sulfur atoms. The action of an electron beam or high temperature transforms the fullerenes into graphene ribbons. The edges of the GNRs obtained were passivated by sulfur; precisely the presence of sulfur, in the opinion of the authors, plays the key role in the success of the synthesis of the material, because it makes the ribbons energetically more favorable structures than the initial material. The same authors have obtained graphene ribbons from tetrathiafulvalene (C6H4S4) placed inside a carbon nanotube."
Yazyev, O. V. (2013), A Guide to the Design of Electronic Properties of Graphene Nanoribbons. Accounts of Chemical Research, doi: 10.1021/ar3001487, Citation: "A complementary approach exploits self-assembly inside carbon nanotubetemplates starting from sulfur-rich organic precursors such as tetrathiafulvalene (TTF) under heating (>800 °C) or subject to electron beam irradiation."
Yin, Q., & Shi, X. (2013), Mechanics of rolling of nanoribbon on tube and sphere. Nanoscale, 5:5450-5455, doi: , Citation: "Several methods have been developed to fabricate GNRs with desired edges, including the self-assembly of fullerenes within a singlewalled carbon nanotube (CNT)."
Zhang, J., Zhu, Z., Feng, Y., Ishiwata, H., Miyata, Y., Kitaura, R., Dahl, J. E. P., Carlson, R. M. K., Fokina, N. A., Schreiner, P. R., Tomanek, D. & Shinohara, H. (2013), Evidence of Diamond Nanowires Formed inside Carbon Nanotubes from Diamantane Dicarboxylic Acid, Angewandte Chemie International Edition, 52: 3717-3721, doi: 10.1002/anie.201209192, Citation: "Under high-intensity electron-beam irradiation, the encapsulated diamond nanostructures were dehydrogenated and reconstructed into sp2 structures. Termination by heavier elements than hydrogen may suppress this transformation."
Akatyeva, E., & Dumitrică, T. (2012), Chiral graphene nanoribbons: Objective molecular dynamics simulations and phase-transition modeling. Journal of Chemical Physics, 137: 234702, doi: 10.1063/1.4770002, Citation: "The possibility of tuning electronic properties through lateral quantum confinement prompted fabrication of graphene nanoribbons (GNRs). GNR morphologies with other chemical edge functionalizations were observed in experiment."
Biskupek, J., P. Hartel, M. Haider, U. A. Kaiser (2012), Effects of residual aberrations explored on single-walled carbon nanotubes. Ultramicroscopy, 116: 1-7, doi: 10.1016/j.ultramic.2012.03.008, Citation: "In order to study SWNTs and graphene at or close to it’s atomic scale a reduction of dE*CC is mandatory by means of special settings of the electron gun, using a monochromator or a CC-corrector. Good results were shown in various recent studies, e. g. by Chuvilin et al. 2011."
Borrnert, F., Fu, L., Gorantla, S., Knupfer, M., Buchner, B., & Rummeli, M. H. (2012), Programmable Sub-nanometer Sculpting of Graphene with Electron Beams. ACS nano, 6: 10327-10334, doi: 10.1021/nn304256a, Citation: "The random production of structured nanocarbons inside a TEM has been reported."
Chamberlain, T. W., Biskupek, J., Rance, G. A., Chuvilin, A., Alexander, T. J., Bichoutskaia, E., Kaiser, U. A., & Khlobystov, A. N. (2012), Size, Structure, and Helical Twist of Graphene Nanoribbons Controlled by Confinement in Carbon Nanotubes. ACS nano, 6: 3943-3953, doi: 10.1021/nn300137j, Citation: "Recently, we reported the use of singlewalled carbon nanotubes (SWNTs) as effective one-dimensional templates for the controlled self-assembly of GNRs. The formation of sulfur-terminated nanoribbons (S-GNR) in our experiments appears to be uninfluenced by the structure or exact chemical composition of the molecular precursors since S-GNRs readily form not only from the sulfur-containing molecule, tetrathiafulvalene (TTF), but also from TTF mixtures with C60 or fullerenes functionalized with sulfur-containing groups. For the detection in AC-HRTEM images the ubiquitous presence of the twist in the nanoribbon structure is the most important characteristic distinguishing GNRs from an internal guest nanotube, which show similar AC-HRTEM contrast, or any other polymeric or amorphous products that may form within the host SWNT structure. The elliptical distortion of the nanotubes can be observed clearly in time series of TEM images. Furthermore, the presence of S-GNRs in nanotubes has an effect on the vibrations of the host SWNT, resulting in a red shift of the radial breathing mode (RBM) bands measured by Raman spectroscopy, which may be related to a combined effect of electron transfer from S-GNR to SWNT."
Chamberlain, T. W., Pfeiffer, R., Howells, J., Peterlik, H., Kuzmany, H., Krautler, B., Da Ros, T., Melle-Franco, M., Zerbetto, F., Milic, D., & Khlobystov, A. N. (2012), Engineering molecular chains in carbon nanotubes. Nanoscale, 4: 7540-7548, doi: 10.1039/C2NR32571C, Citation: "The interior of the nanotube can also be utilised as a template, leading to the formation of new nanostructures possessing exciting properties. The rich and varied reactivity of fullerenes has allowed a wide variety of functional groups to be chemically bound to the carbon cage and the resultant functionalised fullerenes inserted into SWNTs. This methodology has been utilised to introduce a host of organic functional groups."
Dumitrică, T., Kodambaka, S., & Jun, S. (2012), Synthesis, electromechanical characterization, and applications of graphene nanostructures. Journal of Nanophotonics, 6: 064501-1, doi: 10.1117/1.JNP.6.064501, Citation: "Most recently, Chuvilin et al. 2011 have grown narrow graphene ribbons inside carbon nanotubes. The ribbons are formed via electron irradiation of functionalized fullerenes located inside the tubes. The role of the nanotube is to confine propagation of the nanoribbon in one dimension and determines its width. Therefore, this development appears to establish a much needed reliable method to produce nanoribbons with desirable nanometer scale width. Interestingly, the nanoribbons grown by this method are not flat but helically twisted."
Fujihara, M., Miyata, Y., Kitaura, R., Nishimura, Y., Camacho, C., Irle, S., Iizumi, Y., Okazaki, T., & Shinohara, H. (2012), Dimerization-initiated preferential formation of coronene-based graphene nanoribbons in carbon nanotubes. Journal of Physical Chemistry C, 116: 15141-15145, doi: 10.1021/jp3037268, Citation: "Recently, it was also reported that GNRs were synthesized from sulfurcontaining organic molecules and polycyclic aromatic hydrocarbons (PAHs) within CNTs. Considering its large size, we expect that the dicoronylene in nanotubes does not stack on the molecular plane like coronene, but rather parallel to the CNT sidewalls to produce the reported GNRs."
Huang, P. Y., Meyer, J. C., & Muller, D. A. (2012), From atoms to grains: Transmission electron microscopy of graphene. MRS bulletin, 37: 1214-1221, doi: 10.1557/mrs.2012.183, Citation: "Finally, graphene can be turned into fullerenes and vice versa."
Ishii, Y., Song, H., Kato, H., Takatori, M., & Kawasaki, S. (2012), Facile bottom-up synthesis of graphene nanofragments and nanoribbons by thermal polymerization of pentacenes. Nanoscale, 4: 6553-6561, doi: 10.1039/C2NR31893H, Citation: "A promising method for controlling graphene morphology with PAH precursors is a template method that uses single-walled carbon nanotubes (SWCNTs) as a reactor."
Kagimura, R., & Chacham, H. (2012), Knots in a graphene nanoribbon. Physical Review B, 85: 125415, doi: 10.1103/PhysRevB.85.125415, Citation: "Twisted ribbons have been reported in recent experimental works."
Kaiser, U. A. (2012), Low-Voltage TEM to explore physics and chemistry of low-dimensional and low-atomic number materials on the atomic scale. PDF, Citation: "We use graphene and carbon nanotubes as substrates for radiation-sensitive compounds and take advantage of the dynamics of atom knock-on processes under the electron beam to understand fundamental new transformation routes between carbon nanostructures atom-by-atom."
Kaiser, U. A. (2012), Low-voltage TEM-current status and future prospects. EMC 2012, PDF, Citation: "We use graphene and carbon nanotubes as substrates for radiation-sensitive compounds and take advantage of the dynamics of atom knock-on processes under the electron beam to understand fundamental new transformation routes between carbon nanostructures atom-by-atom."
Lebedeva, I. V., Popov, A. M., Knizhnik, A. A., Khlobystov, A. N., & Potapkin, B. V. (2012), Chiral graphene nanoribbon inside a carbon nanotube: ab initio study. Nanoscale, 4: 4522-4529, doi: 10.1039/C2NR30144J, Citation: "Formation of GNRs with well-defined, atomically smooth edges is essential for controlling their electronic properties. However, as discovered very recently, this is possible only by assembly of these nanostructures inside carbon nanotubes (CNTs)."
Li, X. H., Kurasch, S., Kaiser, U., & Antonietti, M. (2012), Synthesis of Monolayer-Patched Graphene from Glucose. Angewandte Chemie International Edition, 51: 9689-9692, doi: 10.1002/anie.201203207, Citation: "The real structure of the as-formed graphene nanosheets is nicely revealed by aberration-corrected high-resolution transmission electron microscopy (AC-HRTEM) observation at the atomic level."
Maeyoshi, Y., Saeki, A., Suwa, S., Omichi, M., Marui, H., Asano, A., Tsukuda, S., Sugimoto, M., Kishimura, A., Kataoka, K., & Seki, S. (2012), Fullerene nanowires as a versatile platform for organic electronics. Scientific reports, 2: 600, doi: 10.1038/srep00600, Citation: "Fullerenes, which have spherical shapes, electron accepting and transport capability, have occupied an important place in organic electronics."
Mandal, B., Sarkar, S., Pramanik, A., & Sarkar, P. (2012), Electronic structure and transport properties of sulfur-passivated graphene nanoribbons. Journal of Applied Physics, 112: 113710, doi: 10.1063/1.4768524, Citation: "The possibility of edge passivation of graphene nanoribbon by sulfur atoms has recently been proved in laboratory."
Pantelic, R. S., Meyer, J. C., Kaiser, U., & Stahlberg, H. (2012), The application of Graphene as a sample support in Transmission Electron Microscopy. Solid State Communications, 152: 1375-1382, doi: 10.1016/j.ssc.2012.04.038, Citation: "Smaller molecules (in particular endohedral fullerenes and metal nanoparticles) have been imaged by HR-TEM after insertion to SWNT's and subsequent preparation as a freestanding sample."
Ramanathan, M., S Michael Kilbey, I. I., Ji, Q., Hill, J. P., & Ariga, K. (2012), Materials self-assembly and fabrication in confined spaces. Journal of Materials Chemistry, 22: 10389-10405, doi: 10.1039/C2JM16629A, Citation: "Very recently Khlobystov and coworkers have outlined a novel strategy for self-assembly of graphene nanoribbons (GNRs) with well-defined atomic structure from a mixture of atoms, using a SWNT as both the reaction vessel and template for nanoribbon growth."
Santana, A., Popov, A. M., & Bichoutskaia, E. (2012), Stability and dynamics of vacancy in graphene flakes: Edge effects. Chemical Physics Letters, 557: 80-87, doi: 10.1016/j.cplett.2012.11.077, Citation: "The AC-TEM has been also exploited in visualization in real time of the process of self-assembly of graphene nanoribbons from molecular precursors."
Shen, H., & Cheng, K. (2012), Tensile properties and thermal conductivity of graphene nanoribbons encapsulated in single-walled carbon nanotube. Molecular Simulation, 38: 922-927, doi: 10.1080/08927022.2012.672739, Citation: "."
Terrones, H. (2012), Beyond Carbon Nanopeapods. ChemPhysChem, 13: 2273-2276, doi: 10.1002/cphc.201200321, Citation: "As has been shown so far, molecules inserted into SWCNTs can react with temperature or by the interaction with an electron beam leaving the SWCNT intact, thus SWCNTs behave as reaction vessels at the nanoscale. Another recent and important example reported by Chuvilin and co-authors consists on the functionalization of C80 molecules with H, N, O and S which inside the SWCNT react, under the electron beam, to form sulfur saturated GNR ([Figure])."
Trendbericht (2012), Makromolekulare Chemie 2011. (only in German) Nachrichten aus der Chemie, 60: 332-345, doi: 10.1002/nadc.201290123, Citation: "Kaiser, Khlobystov and colleagues discovered that a GNR self-assembles from a mixture of functionalized fullerene precursors in single-walled carbon nanotubes. As a result of this, not only the directional growth is achieved, but also the width of the strips can be controlled. Electron microscopic studies showed that the carbon nanotubes are distorted elliptically; the enclosed nanoribbons have a screw-like, helical twist. These results show that the current work provides appropriate ways to control the electronic properties (band gap, concentration of charge carriers) of GNRs."
Wu, K., Qiu, H., Hu, J., Sun, N., Zhu, Z., Li, M., & Shi, Z. (2012), Electrochemistry of double-wall carbon nanotubes encapsulating C< sub> 60 and their spectral characterization. Carbon, 50: 4401-4408, doi: 10.1016/j.carbon.2012.05.016, Citation: "More and more researches are focused on functionalizing CNTs in order to tune their properties to synthesize ideal materials."
Wurm, J., Wimmer, M., & Richter, K. (2012), Symmetries and the conductance of graphene nanoribbons with long-range disorder. Physical Review B, 85: 245418, doi: 10.1103/PhysRevB.85.245418, Citation: "Great effort has been spent on improving the edges of GNRs: they were self-assembled inside carbon nanotubes."
Xu, T., Chen, Q., Zhang, C., Ran, K., Wang, J., Rosentsveig, R., & Tenne, R. (2012), Self-healing of bended WS2 nanotubes and its effect on the nanotube's properties. Nanoscale, 4: 7825-7831, doi: 10.1039/C2NR32591H, Citation: "Focus electron beam in TEM has been used to modify nanostructures such as producing narrow graphene nanoribbons inside a SWCNT."
Yan, L., Zheng, Y. B., Zhao, F., Li, S., Gao, X., Xu, B., Weiss, P. S. & Zhao, Y. (2012), Chemistry and physics of a single atomic layer: strategies and challenges for functionalization of graphene and graphene-based materials. Chemical Society Reviews, 41: 97-114, doi: 10.1039/C1CS15193B, Citation: "Chuvilin et al. reported that sulfur-terminated graphene nanoribbons can spontaneously selfassemble within SWNTs, achieving a conjugate with novel properties."
Zhang, D. B., & Dumitrică, T. (2012), Role of effective tensile strain in electromechanical response of helical graphene nanoribbons with open and closed armchair edges. Physical Review B, 85: 035445, doi: 10.1103/PhysRevB.85.035445, Citation: "Opening a band gap in graphene is an important current research topic. Graphene nanoribbons (GNRs), new one-dimensional materials derived from graphene, are of special importance because the lateral quantum confinement provides one route for band-gap opening and manipulation. Unfortunately current GNR fabrication methodologies do not yet allow for a precise control of GNR widths and edges, and thus for precise band-gap design. However, we note a promising development: In one approach edgeclosed GNRs with enhanced conductivity were achieved after the removal of the metal nanowire on which they were grown."
Zoberbier, T., T. W. Chamberlain, J. Biskupek, N. Kuganathan, E. Bichoutskaia, S. Eyhusen, U. A. Kaiser, A. N. Khlobystov (2012), Interactions and Reactions of Transition Metal Clusters with the Interior of Single-Walled Carbon Nanotubes Imaged at the Atomic Scale. J. Am. Chem. Soc., 134: 3073-3079, doi: 10.1021/ja208746z, Citation: "While conventional spectroscopic methods that integrate over larger volumes (e.g., XPS, Raman, etc.) can be applied for characterizing the bulk physicochemical properties, high-resolution transmission electron microscopy (HRTEM) is now rapidly becoming an excellent local-probe tool for studying chemical reactions in nanotubes by imaging transformations in direct space and real time down to the single-atom level."
Allen, C. S., Ito, Y., Robertson, A. W., Shinohara, H., & Warner, J. H. (2011), Two-dimensional coalescence dynamics of encapsulated metallofullerenes in carbon nanotubes. ACS nano, 5: 10084-10089, doi: 10.1021/nn204003h, Citation: "The range of materials that can be encapsulated inside carbon nanotubes is broad and includes graphene nanoribbons. We have not, however, demonstrated any control over the nature of the intermediate products in the coalescence reaction. Recent work on tailoring the species inserted into carbon nanotube hosts to determine the products of coalescence suggest that it may eventually be possible to deliberately create such structures as those reported in this work."
Banhart, F. (2011), Graphene nanoribbons: Twisted within nanotubes. Nature Materials, 10: 651-652, doi: 10.1038/nmat3106, Citation: "Reporting in Nature Materials, Andrei Khlobystov and co-authors show that carbon nanotubes can be used as reactors to synthesize graphene nanoribbons from functionalized fullerenes ([Figure]). Interestingly, the helical twist modifies the bandgap, as the calculations of Khlobystov and co-authors show."
Khlobystov, A. N. (2011), Carbon nanotubes: from nano test tube to nano-reactor. ACS nano, 5: 9306-9312, doi: 10.1021/nn204596p, Citation: "More recent examples illustrating that confinement in nanotubes leads to the formation of qualitatively different products include graphene nanoribbons ([Figure]). Indeed, some of the reactions discovered by HRTEM, such as the formation of sulfur-terminated graphene nanoribbons, can be successfully replicated on the macroscale."
Westenfelder, B., Meyer, J. C., Biskupek, J., Kurasch, S., Scholz, F., Krill III, C. E., & Kaiser, U. (2011), Transformations of carbon adsorbates on graphene substrates under extreme heat. Nano letters, 11: 5123-5127, doi: 10.1021/nl203224z, Citation: "It is now possible to obtain atomic-resolution images even of light-element materials, with a reduction in radiation damage effected by the utilization of reduced acceleration voltages."
Zubaer Hossain, M. (2011), Semiconducting graphene nanoribbon retains band gap on amorphous or crystalline SiO< inf> 2. Applied Physics Letters, 99: 183103, doi: 10.1063/1.3657494 , Citation: "Graphene nanoribbons (GNRs) show distinct material properties from those of other carbon allotropes."
Gao, J., P. Blondeau, P. Salice, E. Menna, B. Bartova, C. Hebert, J. Leschner, U. A. Kaiser, M. Milko, C. Ambrosch-Draxl, M. A. Loi (2011), Electronic Interactions between "Pea" and "Pod": The Case of Oligothiophenes Encapsulated in Carbon Nanotubes. Small, 7: 1807-1815, doi: 10.1002/smll.201100319. Cited by (5)
Cataldo, S., Salice, P., Menna, E., & Pignataro, B. (2012), Carbon nanotubes and organic solar cells. Energy & Environmental Science, 5: 5919-5940, doi: 10.1039/C1EE02276H, Citation: "The subsequent development of milder processes disclosed the possibility to encapsulate different organic molecules ([Figure])."
Gao, J., Gomulya, W., & Loi, M. A. (2012), Effect of medium dielectric constant on the physical properties of single-walled carbon nanotubes. Chemical Physics, 413: 35-38, doi: 10.1016/j.chemphys.2012.11.003, Citation: "The optical properties of SWNTs are of great importance not only because they can help in the understanding of their fundamental physical properties, but also because of the potential application of SWNTs in nano-photonic devices."
- Hebert, C., Biskupek, J., Kaiser, U., Salice, P., Menna, E., Milko, M., Ambrosch-Draxl, C., Gao, J., Loi, M. A., & Bartova, B. (2012), Dynamical behavior of organic molecules encapsulated in single wall carbon nanotubes investigated by Aberration Corrected-HRTEM, EMC 2012, PDF, Citation: "Recently, the very first peapods with photoluminescence (PL) emission in the visible spectral range have been demonstrated by our team."
Milko, M., & Ambrosch-Draxl, C. (2011), Energetics and structure of organic molecules embedded in single-wall carbon nanotubes from first principles: The example of benzene. Physical Review B, 84: 085437, doi: 10.1103/PhysRevB.84.085437, Citation: "From the above values, one can estimate that the molecule inside the narrow (12,0) tube should stand still at temperatures below around 800 K, while inside (13,0) it can be expected to rotate already far below room temperature. Such behavior has indeed been observed by high-resolution TEM recently. Moreover, the binding energies, are computed with the same unit cells for the peapod of noninteracting molecules, as the unit cells are commensurate."
Yamashita, H., & Yumura, T. (2012), The Role of Weak Bonding in Determining the Structure of Thiophene Oligomers inside Carbon Nanotubes. Journal of Physical Chemistry C, 116: 9681-9690, doi: 10.1021/jp301972e, Citation: "Loi et al. and Gao et al. reported the synthesis of thiophene oligomers inside a nanotube and demonstrated this encapsulation using high-resolution transmission electron microscopy in conjunction with both optical and Raman spectroscopies. Moreover, Density Functional Theory (DFT) calculations can provide us with useful insight into the structure of organic molecules inside nanotubes."
Gimenez-Lopez, M. del C., A. Chuvilin, U. A. Kaiser & A. N. Khlobystov (2011), Functionalised endohedral fullerenes in single-walled carbon nanotubes. Chem. Commun., 47: 2116-2118, doi: 10.1039/C0CC02929G. Cited by (7)
Karousis, N., Sato, Y., Suenaga, K., & Tagmatarchis, N. (2012), Direct evidence for covalent functionalization of carbon nanohorns by high-resolution electron microscopy imaging of C60 conjugated onto their skeleton. Carbon, 50: doi: 10.1016/j.carbon.2012.04.035, Citation: "Actually, when carbon nanotubes used as specimen support or as host material for encapsulation, fullerene spheres have been imaged and identified with TEM."
Lu, X., Feng, L., Akasaka, T., & Nagase, S. (2012), Current status and future developments of endohedral metallofullerenes. Chemical Society Reviews, 41: 7723-7760, doi: 10.1039/C2CS35214A, Citation: "In fact, functionalized EMF (i.e. pyrrolidine-adduct of Sc3N@C80) have been filled inside SWNTs."
Popov, A. A., Yang, S., & Dunsch, L. (2013), Endohedral Fullerenes. Chemical reviews, In Press, doi: 10.1021/cr300297r, Citation: "In an aberration-corrected TEM study of endohedral fullerene peapods in 2011, Kaiser, Khlobystov and co-workers managed to encapsulate Sc3N@C80 as well as its pyrrolidine adduct bearing an alkyl chain with a dithiolane group into SWNT and obtained images of the Sc3N cluster positions with respect to the carbon cage by AC-HRTEM as the first report of functionalized endohedral fullerene-based peapod."
Chuvilin, A., Bichoutskaia, E., Gimenez-Lopez, M. C., Chamberlain, T. W., Rance, G. A., Kuganathan, N., Biskupek, J., Kaiser, U. A., & Khlobystov, A. N. (2011), Self-assembly of a sulphur-terminated graphene nanoribbon within a single-walled carbon nanotube. Nature Materials, 10: 687-692, doi: 10.1038/nmat3082, Citation: "Time series of aberration-corrected high resolution transmission electron microscopy (AC-HRTEM) images reveal that the functional groups of these molecules become fragmented by the 80 keV electron beam."
Gao, J., Blondeau, P., Salice, P., Menna, E., Bartova, B., Hebert, C., Leschner, J., Kaiser, U. A., Milko, M., Ambrosch-Draxl, C., & Loi, M. A. (2011), Electronic Interactions between "Pea" and "Pod": The Case of Oligothiophenes Encapsulated in Carbon Nanotubes. small, 7: 1807-1815, doi: 10.1002/smll.201100319, Citation: "Hardening and stiffening of C-C bonds is in good agreement with previously reported characterizations of fullerene-based peapod materials. Up to now, however, only a few cases of filling SWNTs with complex organic molecules have been demonstrated."
Kaiser, U. (2011), Imaging and Spectroscopy of Carbon Nanostructures with 80 and 20 keV Electrons. Microscopy and Microanalysis, 17: 1488-1489, doi: 10.1017/S1431927611008312, Citation: "At 80 keV, AC-HRTEM provides structural information on both, the exterior (functional groups) and/or the interior of individual fullerenes and metallofullerenes at the near-atomic level in direct space and real time."
Lu, X., Akasaka, T., & Nagase, S. (2011), Chemistry of endohedral metallofullerenes: the role of metals. Chemical Communications, 47: 5942-5957, doi: 10.1039/C1CC10123D, Citation: "In addition, with the confinement of CNTs, the endohedral metallofullerenes (EMFs) are uniformly arranged inside, which enables direct observation of the movements of metals and/or the cages and promises several novel applications such as quantum computing units, high-density memories, drug carriers and nano reactors. However, the insertion of EMF-derivatives inside CNTs is rarely reported."
Kaiser, U. A., J. Biskupek, J. C. Meyer, J. Leschner, L. Lechner, H. H. Rose, M. Stoger-Pollach, A. N. Khlobystov, P. Hartel, H. Muller, M. Haider, S. Eyhusen, G. Benner (2011), Transmission electron microscopy at 20 kV for imaging and spectroscopy. Ultramicroscopy, 111: 1239-1246, doi: 10.1016/j.ultramic.2011.03.012. Cited by (42)
Bell, D. C. (2013), Chapter 5 Low Voltage High-Resolution Transmission Electron Microscopy. In: Low Voltage Electron Microscopy: Principles and Applications, Bell, D. C. & Erdman, N. (Eds.), John Wiley & Sons (London): 97-117, doi: 10.1002/9781118498514.ch5, Citation: "."
Borrnert, F., Bachmatiuk, A., Gorantla, S., Wolf, D., Lubk, A., Buchner, B., & Rummeli, M. H. (2013), Retro-fitting an older (S) TEM with two Cs aberration correctors for 80 kV and 60 kV operation. Journal of microscopy, 249: 87-92, doi: 10.1111/j.1365-2818.2012.03684.x, Citation: "The increased resolving power afforded by Cs aberration correctors has expanded the use of low energy electron beams into the high-resolution regime. There are even developments towards sub-80 kV atomic resolution imaging, e.g. TEM imaging has been reported 20 kV (Kaiser et al., 2011),"
Egerton, R. F. (2013), Control of radiation damage in the TEM. Ultramicroscopy, 127: 100-108, doi: 10.1016/j.ultramic.2012.07.006, Citation: "Kaiser et al. found that visible damage to C60 molecules embedded in a double-walled carbon nanotube required about 100 times more electron dose at 20 keV compared to 80 keV, where the damage dose was about 160C/cm2."
Grunwaldt, J. D., Wagner, J. B., & Dunin-Borkowski, R. E. (2013), Imaging Catalysts at Work: A Hierarchical Approach from the Macro-to the Meso-and Nano-scale. ChemCatChem, 5: 62-80, doi: 10.1002/cctc.201200356, Citation: "Present state-of-the-art chemical characterisation of variations in chemical composition in individual metal and oxide nanoparticles could be extended in the future by the use of new generations of aberration correctors."
Haigh, S. J., Jiang, B., Alloyeau, D., Kisielowski, C., & Kirkland, A. I. (2013), Recording low and high spatial frequencies in exit wave reconstructions. Ultramicroscopy, 133: 26-34, doi: 10.1016/j.ultramic.2013.04.012, Citation: "We also note that recent work has shown that high resolution at low voltage is limited by partial temporal coherence and benefits significantly from chromatic aberration correction which is not considered in the calculations presented here."
Kaiser, U. A. (2013), Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope, Graphene 2013, PDF, Citation: "The atomic structure and electronic properties of graphene and other low-dimensional objects are obtained by analytical low-voltage aberration-corrected high-resolution transmission electron microscopy. In the spectroscopy mode we show that the monochromatic low-energy electron beam enables the acquisition of EELS spectra with exceptionally low background noise."
Kimoto, K., & Ishizuka, K. (2013), Quantitative assessment of lower-voltage TEM performance using 3D Fourier transform of through-focus series, MSC/SMC Annual Meeting 2013, PDF, Citation: "The spherical aberration corrector was a quantum leap forward in high-resolution transmission electron microscopy (TEM). It brought about a breakthrough in high-resolution lower-voltage TEM, and a variety of novel nanostructured materials have been explored utilizing its high spatial resolution, high image contrast and low knock-on damage."
Lee, Z., Rose, H., Hambach, R., Wachsmuth, P., & Kaiser, U. (2013), The influence of inelastic scattering on EFTEM images-exemplified at 20 kV for graphene and silicon. Ultramicroscopy, In Press, doi: 10.1016/j.ultramic.2013.05.020, Citation: "However, due to radiation damage caused by atom displacement at higher accelerating voltages >100 kV, the use of lower voltages (20-80 kV) becomes necessary as realized within the frame of the SALVE (Sub-Angstrom Low-Voltage Electron microscopy) project."
Lichte, H., Borrnert, F., Lenk, A., Lubk, A., Roder, F., Sickmann, J., Sturm, S., Vogel, K., & Wolf, D. (2013), Electron Holography for fields in solids: Problems and progress. Ultramicroscopy, In Press, doi: 10.1016/j.ultramic.2013.05.014, Citation: "In face of the growing interest in light element materials such as carbon, low accelerating voltages are increasingly interesting for TEM-methods in order to reduce knock-on beam damage."
Linck, M. (2013), Optimum Aberration Coefficients for Recording High-Resolution Off-Axis Holograms in a Cs-corrected TEM. Ultramicroscopy, 124: 77-87, doi: 10.1016/j.ultramic.2012.08.006, Citation: "Hardware aberration correction with in the transmission electron microscope (TEM) has brought a long list of improvements for analysis on the atomic scale."
Meyer, J. (2013), New horizons and challenges in the microscopic characterization of 2-D materials, Graphene 2013, PDF, Citation: "The recent developments in aberration-corrected electron optics open a route to a atomically-resolved studies of these materials at reduced electron energies below the knock-on threshold of carbon atoms in graphene."
Muoth, M. (2013), Clean integration of single-walled carbon nanotubes for electromechanical systems, Doctoral dissertation, Eidgenossische Technische Hochschule ETH Zurich, 20887, doi: PDF, Citation: "Aberration-corrected low-voltage TEM at 20 kV improves contrast for carbon materials and enhances stability of beam-sensitive objects such as fullerenes."
Ricolleau, C., Nelayah, J., Oikawa, T., Kohno, Y., Braidy, N., Wang, G., Hue, F., Florea, L., Bohnes, V. P., & Alloyeau, D. (2013), Performances of an 80-200 kV microscope employing a cold-FEG and an aberration-corrected objective lens. Microscopy, 62: 283-293, doi: 10.1093/jmicro/dfs072, Citation: "The resolution was measured with the commonly used minimum contrast level of 13.5%."
Barton, B., Jiang, B., Song, C., Specht, P., Calderon, H., & Kisielowski, C. (2012), Atomic Resolution Phase Contrast Imaging and In-Line Holography Using Variable Voltage and Dose Rate. Microscopy and Microanalysis, 1: 1-13, doi: 10.1017/S1431927612001213, Citation: "Currently, strategies emerge to address this matter with low voltage microscopy. Aberration correction remains a limiting factor for resolution at 20 keV, which is why this matter is currently addressed worldwide."
Bell, D. C., Russo, C. J., & Kolmykov, D. V. (2012), 40keV atomic resolution TEM. Ultramicroscopy, 114: 31-37, doi: 10.1016/j.ultramic.2011.12.001, Citation: "Examination near the thin amorphous edge reveals the Si dumbbells ([Figure]), {004} spacing measured at 1.36 A, which is in good agreement with the values by Kaiser et al. 2011."
Carbone, F., Musumeci, P., Luiten, O. J., & Hebert, C. (2012), A perspective on novel sources of ultrashort electron and X-ray pulses. Chemical Physics, 392: 1-9, doi: 10.1016/j.chemphys.2011.10.010, Citation: "Lower voltages seem to have only advantages, the knock-on beam damage is lower and sensitive materials can be imaged for hours without being destroyed."
Chisholm, M. F., Duscher, G., & Windl, W. (2012), Oxidation Resistance of Reactive Atoms in Graphene. Nano letters, 12: 4651-4655, doi: 10.1021/nl301952e, Citation: "The use of microscope operating voltages below the knock-on damage threshold of sp2 bonded carbon has also been discussed."
Egerton, R. F. (2012), Mechanisms of radiation damage in beam-sensitive specimens, for TEM accelerating voltages between 10 and 300 kV. Microscopy Research and Technique, 75: 1550-1556, doi: 10.1002/jemt.22099, Citation: "Atomic-scale imaging has been demonstrated with aberration-corrected monochromated TEM operating at 20 kV."
Egerton, R. F. (2012), TEM-EELS: a personal perspective. Ultramicroscopy, 119 24-32, doi: 10.1016/j.ultramic.2011.11.008, Citation: "Some aspects, such as atomic resolution at low voltage, have since been realized.
Golla-Schindler, U., Algara-Siller, G., Orchowski, A., Wu, Y., Weil, T., & Kaiser, U. (2012), First results of 20 kV EFTEM of core-shell QDS with an albumin-derived polypeptide surface coating on graphene, EMC 2012, PDF, Citation: "Elastic (electron-nucleus) damage mechanisms decrease significantly and the inelastic (electron-electron) damage mechanisms increase, therefore specimens and specimen conditions need to be selected carefully. The investigations were performed with the monochromized and imaging aberration-corrected SALVE1 microscope operating at 20 kV equipped with a 4kx4k CMOS Tietz camera (F416) with an energy slit width of 1.1 eV, an energy resolution of 0.18 eV (FWHM of ZLP)."
Hambach, R., Giorgetti, C., Reining, L., Wachsmuth, P., Benner, G., & Kaiser, U. (2012), Collective electronic excitations in graphene-based systems: first-principle and model calculations, EMC 2012, PDF, Citation: "We present first experimental results obtained on a low-voltage optimized Libra-based transmission electron microscope prototype (ZEISS) which is equipped with an electrostatic monochromator and a CS corrector."
Holmstrom, E. (2012), Radiation effects in bulk and nanostructured silicon, Dissertation University of Helsinki, HU-P-D191, doi: PDF, Citation: "The current trend in AC-HRTEM is to use lower and lower electron beam voltages, as low as 20 kV, down from the usual 200 or 300 kV, in order to prevent displacement damage in fragile samples. Moreover, drawing together the findings from the experiments and simulations, we can now construct an explanation as to why the conventional thinning method fails, and conversely, why the doubletilt method delivers superior performance. The reason is simply that there is no free edge in the lamella structure in this approach, and hence the direct vertical shrinkage of lamella edges and the bending of the lamella top edge towards the incident beam are not present. The thinning may proceed well below 20 nm, demonstrably to as low as 4 nm."
Holmstrom, E., Kotakoski, J., Lechner, L., Kaiser, U., & Nordlund, K. (2012), Atomic-scale effects behind structural instabilities in Si lamellae during ion beam thinning. AIP Advances, 2: 012186, doi: 10.1063/1.3698411, Citation: "The current development in AC-HRTEM is to lower the voltage from the usual 200-300 kV to well below 100 kV. So far, predominantly low-dimensional materials such as graphene have been studied."
Kaiser, U. A. (2012), Low-Voltage TEM to explore physics and chemistry of low-dimensional and low-atomic number materials on the atomic scale, Graphene 2012, PDF, Citation: "Recently, microscope develoments are addressing electron energies down to 20keV because many low-Z materials require imaging at energies appreciably lower than 60keV."
Kaiser, U. A. (2012), Low-voltage TEM-current status and future prospects, EMC 2012, PDF, Citation: "Recently microscope develoments are addressing electron energies down to 20keV, because many low-Z materials require imaging at energies appreciably lower than 60 keV."
Kinyanjui, M. K., Kramberger, C., Pichler, T., Meyer, J. C., Wachsmuth, P., Benner, G., & Kaiser, U. (2012), Direct probe of linearly dispersing 2D interband plasmons in a free-standing graphene monolayer. EPL, 97: 57005, doi: 10.1209/0295-5075/97/57005, Citation: "Our EELS investigations were done on a Libra-based transmission electron microscope prototype (ZEISS) operating at 20 kV."
Lechner, L., Biskupek, J., & Kaiser, U. (2012), Improved Focused Ion Beam Target Preparation of (S) TEM Specimen—A Method for Obtaining Ultrathin Lamellae. Microscopy and Microanalysis, 18: 379, doi: 10.1017/S1431927611012499, Citation: "Scientists have rediscovered the advantages of using low energies in TEM; it dramatically reduces knock-on damage for low-Z number material and enables new results in imaging and electron energy loss spectroscopy (EELS). EELS spectra were acquired with the integrated in-column energy filter, and sample thickness was determined by Kramer-Kronig analysis. The HRTEM image of the lamella was obtained with a spherical aberration-corrected TEM operated at 20 kV. The associated power spectrum ~inset! clearly exhibits Si 100 reflexes; diffuse intensity rings, an indicator for amorphization, are notably absent. The background contrast variation in the HRTEM image is thus primarily attributable to surface roughness creating strong Bragg contrast at 20 kV. The total window thickness at the imaging location was determined to be 4 nm by EELS measurement (for more details, specifications, and performance of the dedicated low voltage TEM platform, see Kaiser et al., 2011),"
Lee, Z., Meyer, J. C., Rose, H., & Kaiser, U. (2012), Optimum HRTEM image contrast at 20 kV and 80 kV—Exemplified by graphene. Ultramicroscopy, 112: 39-46, doi: 10.1016/j.ultramic.2011.10.009. Citation: "Recently we first reported experimental findings on spherical aberration-corrected high-resolution transmission electron microscopy (HRTEM) image contrast of graphene and silicon at 20 kV. The next generation of electron microscopes aims for spherical and chromatic aberration correction, which is mandatory at low voltages. Within the frame of the Sub-Angstrom Low-Voltage Electron Microscopy (SALVE) project our team is currently working on the construction of a microscope that corrects aberrations of the objective lens to such an extent that a resolution of 172 pm at 20 kV will be achieved (this implies that an aperture angle up to 50 mrad can be used). The chromatic aberration coefficient for this microscope is CC=1.41 mm at 80 kV and CC=1.26 mm at 20 kV. For the 20 kV case, EELS spectra were recorded using a monochromated Zeiss Libra 200 equipped with an in-column energy filter. Although we obtained experimental images of graphene at 20 kV, these were not analyzed due to incomplete compensation of geometric aberrations in this preliminary experimental setup."
Lee, Z., Rose, H., Hambach, R., & Kaiser, U. (2012), EFTEM image calculation based on mutual coherence approach, EMC 2012, PDF, Citation: "In accordance with our previous calculations we employed the experimental EELS spectra for the simulation of the EFTEM images."
Meyer, J. C., F. Eder, S. Kurasch, V. Skakalova, J. Kotakoski, H.-J. Park, S. Roth, A. Chuvilin, S. Eyhusen, G. Benner, A. V. Krasheninnikov, U. A. Kaiser (2012), Accurate Measurement of Electron Beam Induced Displacement Cross Sections for Single-Layer Graphene. Phys. Rev. Lett., 108: 196102, doi: 10.1103/PhysRevLett.108.196102, Citation: "We also studied 12C graphene under 20 keV electron irradiation. For 20 kV imaging, we used an imageside aberration-corrected Zeiss Libra."
Moorthy, S. K. E., Biskupek, J., van Mierlo, W., Bernhard, J., Geiger, D., Benner, G., Wohlfahrt-Mehrens, M., & Kaiser, U. (2012), Electron microscopic characterization of Li-O2 batteries: Clean, green electrochemical energy storage, EMC 2012, PDF, Citation: "We used both CS-corrected Titan (operating at 80 kV) and the Sub-Angstrom Low-Voltage Electron Microscope (SALVE) (operating at 20 and 40 kV) to study voltage-dependent irradiation damage on various Li based compounds."
Stoger-Pollach, M. (2012), Hunting the Silicon loss function with 13 keV electrons in a TEM, EMC 2012, PDF, Citation: "Earlier studies with 20 keV still show a faint signature of these relativistic energy losses in the EELS spectrum."
Stoger-Pollach, M., Hetaba, W., & Loffler, S. (2012), Is there a chance for mapping optical properties of buried quantum structures by means of Low Voltage Valence EELS in a STEM?, EMC 2012, PDF, Citation: "In the last few years, the energy range of incident electron beams in transmission electron microscopes (TEMs) for quantitative analysis has been extended towards lower beam energies. One of the main driving forces behind this development is the reduction of radiation damage within the specimen."
Susi, T., Kotakoski, J., Arenal, R., Kurasch, S., Jiang, H., Skakalova, V., Stephan, O., Krasheninnikov, A. V., Kauppinen, E. S., Kaiser, U. A., & Meyer, J. C. (2012), Atomistic Description of Electron Beam Damage in Nitrogen-Doped Graphene and Single-Walled Carbon Nanotubes. ACS nano, 6: 8837-8846, doi: 10.1021/nn303944f, Citation: "Clearly, to avoid misidentifying the dopant structures of the pristine material, it is imperative to either carefully limit the dose or make sure the spectrum time series shows no changes during an EELS experiment. Alternatively, the primary beam energy of the microscope should be below 60 kV."
Tiemeijer, P. C., Bischoff, M., Freitag, B., & Kisielowski, C. (2012), Using a monochromator to improve the resolution in TEM to below 0.5 Å. Part I: Creating highly coherent monochromated illumination. Ultramicroscopy, 114: 72-81, doi: 10.1016/j.ultramic.2012.01.008, Citation: "It has been demonstrated that monochromation can yield atomic resolution at high tensions as low as 20 - 50 kV."
Van Tendeloo, G., Bals, S., Van Aert, S., Verbeeck, J., & Van Dyck, D. (2012), Advanced Electron Microscopy for Advanced Materials. Advanced Materials, 24: 5655-5675, doi: 10.1002/adma.201202107, Citation: "Lower acceleration voltages are of crucial importance to avoid knock-on beam damage, but a loss of resolution is to be expected. However, aberration-corrected TEM systems are still able to reach spatial atomic resolution at voltages as low as 20 kV."
Wachsmuth, P., Hambach, R., Kinyanjui, M., Benner, G., & Kaiser, U. (2012), Momentum dependent electron energy-loss in single and multi-layer graphene, EMC 2012, doi: PDF, Citation: "Experiments were done on a Libra-based TEM prototype (ZEISS) operated at 20 kV and 40kV."
Walter, A., Muzik, H., Vieker, H., Turchanin, A., Beyer, A., Golzhauser, A., Lacher, M., Steltenkamp, S., Schmitz, s., Holik, P., Kuhlbrandt, W., & Rhinow, D. (2012), Practical aspects of Boersch phase contrast electron microscopy of biological specimens. Ultramicroscopy, 116: 62-72, doi: 10.1016/j.ultramic.2012.03.009, Citation: "Acceleration voltages of 20 kV have other advantages, such as increased contrast of light elements and lower knock-on damage."
Zach, J., Uhlemann, S., & Hartel, P. (2012), Chromatic correction: Chances and fundamental limitations of an evolving corrector technology, EMC 2012, PDF, Citation: "We will discuss several application classes, which benefit most from chromatic correction. In imaging at acceleration voltages below 50 kV as in the German SALVE project this type of correction enables for the first time atomic resolution with reasonable contrast in Transmission Electron Microscopy (TEM)."
Zoberbier, T., Chamberlain, T. W., Biskupek, J., Kuganathan, N., Eyhusen, S., Bichoutskaia, E., Kaiser, U. A., & Khlobystov, A. N. (2012), Interactions and reactions of transition metal clusters with the interior of single-walled carbon nanotubes imaged at the atomic scale. Journal of the American Chemical Society, 134, 3073-3079, doi: 10.1021/ja208746z, Citation: "For 20 keV AC-HRTEM experiments, special modifications were applied regarding the corrector and base setup."
Khlobystov, A. N. (2011), Carbon nanotubes: from nano test tube to nano-reactor. ACS nano, 5: 9306-9312, doi: 10.1021/nn204596p, Citation: "However, if the energy and dose of the electrons are carefully controlled, the in situ transformations can provide valuable information about the chemical properties of the molecules and shed light on their reactivity in the confined environment."
Westenfelder, B., Meyer, J. C., Biskupek, J., Kurasch, S., Scholz, F., Krill III, C. E., & Kaiser, U. A. (2011), Transformations of carbon adsorbates on graphene substrates under extreme heat. Nano letters, 11: 5123-5127, doi: 10.1021/nl203224z, Citation: "It is now possible to obtain atomic-resolution images even of light-element materials, with a reduction in radiation damage effected by the utilization of reduced acceleration voltages."
Kotakoski, J., Krasheninnikov, A. V., Kaiser, U., & Meyer, J. C. (2011). From point defects in graphene to two-dimensional amorphous carbon. Physical Review Letters, 106: 105505, doi: 10.1103/PhysRevLett.106.105505. Cited by (124)
Kotakoski, J., J. C. Meyer, S. Kurasch, D. Santos-Cottin, U. A. Kaiser, & A. V. Krasheninnikov (2011), Stone-Wales-type transformations in carbon nanostructures driven by electron irradiation. Phys. Rev. B, 83: 245420 (6 pages), doi: 10.1103/PhysRevB.83.245420. Cited by (49)
Biro, L. P., & Lambin, P. (2013), Grain boundaries in graphene grown by chemical vapor deposition. New Journal of Physics, 15, 035024, doi: 10.1088/1367-2630/15/3/035024, Citation: "The displacement energy threshold of atoms in the central area of reconstructed defects is higher than that of pristine graphene by as much as 5%."
Chen, C. T., Casu, E. A., Gajek, M., & Raoux, S. (2013), Ultra-Low Damage High-Throughput Sputter Deposition on Graphene. arXiv preprint, arXiv: 1303.3325, Citation: "Both density-functional molecular dynamics simulation (DFT-MD) and the tight-binding (DFTB) model calculate Ed to be 22-23 eV in graphene. One can then estimate how energetic the incident electrons needs to be using the elastic Coulomb scattering model. In this approximation, the maximum energy transfer to the C atoms, Tmax, is related to the incident electron energy Ee by [Formula]. The energy threshold for ejection of C atoms along the in-plane direction is much higher (Ed ranges from 43 eV to >>100 eV)."
Chernozatonskii, L. A., Artyukh, A. A., & Demin, V. A. (2013), Quasi-one-dimensional fullerene-nanotube composites: Structure, formation energetics, and electronic properties. JETP letters, 97: 113-119, Citation: "A low density of Stone-Wales defects on the nanotubes remains stable at room temperature owing to a high barrier of the reverse bond rotation (~5 eV)."
Lee, J., Zhou, W., Pennycook, S. J., Idrobo, J. C., & Pantelides, S. T. (2013), Direct visualization of reversible dynamics in a Si6 cluster embedded in a graphene pore. Nature communications, 4: 1650, doi: 10.1038/ncomms2671, Citation: "Electron-beam-induced ejection of carbon atoms and defect creation/migration has been actively studied in graphene and carbon nanotubes."
Meyer, J. (2013), New horizons and challenges in the microscopic characterization of 2-D materials, Graphene 2013, PDF, Citation: "An electron beam can be used to selectively suppress and enhance bond rotations and atom removal in graphene, which allows to turn graphene into a two-dimensional coherent amorphous membrane composed of sp2-hybridized carbon atoms."
Mi, X., & Shi, Y. (2013), Topological Defects in Nanoporous Carbon. Carbon, 60: 202-214 doi: 10.1016/j.carbon.2013.04.013, Citation: "The SW method, as a virtual synthesis procedure, can be correlated to irradiation processing in which SW transformations occur frequently."
Robertson, A. W., & Warner, J. H. (2013), Atomic resolution imaging of graphene by transmission electron microscopy. Nanoscale, 5: 4079-4093, doi: 10.1039/C3NR00934C, Citation: "The structure is the result of two bond reconstructions after the ejection of a pair of atoms, leading to a 5-, 8-, 5-membered ring sequence, often labelled as a (5-8-5) vacancy. This basic case can evolve under the electron beam, leading to two further restructured defect configurations. A SW rotation of the red highlighted bond in [Figure] a leads to a (555-777) structure, with an AC-TEM image and an atomistic model shown in Fig. b and c, respectively."
Saloriutta, K. (2013), Electron transport in graphene nanostructures. Doctoral Dissertation Aalto University, 7, Citation: "Defects can also be formed without the removal of atoms. Most prominent of these is the topological Stone-Wales defect (SW) formed by rotating one carbon-carbon bond."
Santana, A., Zobelli, A., Kotakoski, J., Chuvilin, A., & Bichoutskaia, E. (2013), Inclusion of radiation damage dynamics in high-resolution transmission electron microscopy image simulations: The example of graphene. Physical Review B, 87: 094110, doi: 10.1103/PhysRevB.87.094110, Citation: "The displacement threshold energies have been calculated by employing the density functional theory-based tight binding model in molecular dynamics simulations. Typically, the structure of a newly formed fullerene does not correspond to the most stable isomer and contains seven-member rings as well as abutting pentagons. Under the continued high-temperature exposure, such imperfect cages could anneal via a series of Stone-Wales rearrangements."
Skowron, S. T., Lebedeva, I. V., Popov, A. M., & Bichoutskaia, E. (2013), Approaches to modelling irradiation-induced processes in transmission electron microscopy. Nanoscale, Advance Article, doi: 10.1039/C3NR02130K, Citation: "Electron irradiation-induced processes in HRTEM have attracted considerable interest in recent decades; these include the creation of single vacancies and other atomic scale defects. The creation of atomic scale lattice defects has been extensively studied in graphene. The formation and subsequent relaxation of isolated Stone–Wales (SW) defects and multiple 5–7 defects was observed in site. The migration and reconstruction of divacancies were induced by the HRTEM e-beam on a graphene layer."
Yamijala, S. S., & Pati, S. K. (2013), Electronic and Magnetic Properties of Zigzag Boron-Nitride Nanoribbons with Even and Odd-line Stone-Wales (5-7 pair) Defects. Journal of Physical Chemistry C, 117, doi: 10.1021/jp310614u, Citation: "Several studies have already addressed the effects of 5−7 point defects in graphene."
Zhu, J., & Shi, D. (2013), A possible self-healing mechanism in damaged graphene by heat treatment. Computational Materials Science, 68: 391-395, doi: 10.1016/j.commatsci.2012.10.041, Citation: "Structural damage and defects, such as holes and vacancies are not thermodynamically dominant in graphene due to their high formation energies, but they do appear during growth, by chemical treatment or in irradiation environments [6,7]. In the following stage, the octagons shown on the left side of the next figure gradually evolve into a more stable double vacancies structure with two pentagons and one octagon (5-8-5 defect, see [Figure]), which is also frequently observed in electron microscopy experiments."
Ahlgren, E. H., Kotakoski, J., Lehtinen, O., & Krasheninnikov, A. V. (2012), Ion irradiation tolerance of graphene as studied by atomistic simulations. Applied Physics Letters, 100: 233108, doi: 10.1063/1.4726053, Citation: "Vacancies in graphene tend to partially "heal" themselves by forming non-hexagonal rings due to bond rotations."
Bonilla, L. L., & Carpio, A. (2012), Driving dislocations in graphene. Science, 337: 161-162, doi: 10.1126/science.1224681, Citation: "More complicated defect rings than nonagon-pentagon and pentagon-octagon-pentagon defects and dynamics have been observed."
Fujita, J. I., Takahashi, T., Ueki, R., Hikata, T., Okubo, S., Utsunomiya, R., & Matsuba, T. (2012), Enormous shrinkage of carbon nanotubes by supersonic stress and low-acceleration electron beam irradiation. Journal of Vacuum Science & Technology B, 30: 03D105, doi: 10.1116/1.3694027, Citation: "It is well known that high energy electron irradiation induces a variety of structural changes in carbon nanotubes; perpendicularly incident electrons induce lateral ejection of carbon atoms; thus creating Stone-Wales (SW) defects on the honeycomb lattice."
Hawelek, L., Woznica, N., Brodka, A., Fierro, V., Celzard, A., Bulou, A., & Burian, A. (2012), Graphene-like structure of activated anthracites. Journal of Physics: Condensed Matter, 24: 495303, doi: 10.1088/0953-8984/24/49/495303, Citation: "In the second approach, the distorted structure was generated assuming the presence of defects in the form of among others mono- and di-vacancy defects."
Huang, P. Y., Meyer, J. C., & Muller, D. A. (2012), From atoms to grains: Transmission electron microscopy of graphene. MRS bulletin, 37: 1214-1221, doi: 10.1557/mrs.2012.183, Citation: "(S)TEM images such as those in [Figure] have shown that many of these defects are formed from or reconstruct into similar building blocks: Pentagons, heptagons, or rings of other sizes replace the hexagons in graphene while maintaining sp 2 bonding. An electron beam whose energy lies above the damage threshold of graphene can create defects, first by removing atoms from the lattice and then by triggering a variety of other modifications in the structure, especially transitions between different defect geometries. At electron energies around 80-100 kV, damage occurs slowly enough that resulting defect configurations can be imaged before subsequent changes occur in the structure. This makes it possible to catalog the likely defect configurations in graphene and to investigate the energetics of transformations among them."
Ivanovskii, A. L. (2012), Graphene-based and graphene-like materials. Russian Chemical Reviews, 81: 571, doi: 10.1070/RC2012v081n07ABEH004302, Citation: "Vacancy formation can be accompanied by partial amorphization and deformation of specimens. Experimental and theoretical studies showed that vacancy formation is accompanied by rearrangement of the nearest C7C bonds and the formation of a nonagon and a pentagon to minimize the number of dangling bonds (Figure)."
Jing, N., Xue, Q., Ling, C., Shan, M., Zhang, T., Zhou, X., & Jiao, Z. (2012), Effect of defects on Young's modulus of graphene sheets: a molecular dynamics simulation. RSC Advances, 2: 9124-9129, doi: 10.1039/C2RA21228E, Citation: "The reconstructed defects as seen in this [Figure] have experimentally been observed by high resolution transmission electron microscopy."
Kirchwehm, Y., Damme, A., Kupfer, T., Braunschweig, H., & Krueger, A. (2012), Ortho-methylated tribenzotriquinacenes—paving the way to curved carbon networks. Chemical Communications, 48: 1502-1504, doi: 10.1039/C1CC14703J, Citation: "One of the major issues of the structure of graphene is the existence of lattice defects related to the insertion of non-hexagonal rings, i.e. pentagons and heptagons."
Kirkland, A. I., & Warner, J. H. (2012), Spatial control of defect creation in graphene at the nanoscale. Nature, 3: 1-7, doi: 10.1038/ncomms2141, Citation: "."
Kumar, A., Wilson, M., & Thorpe, M. F. (2012), Amorphous graphene: a realization of Zachariasen’s glass. Journal of Physics: Condensed Matter, 24: 485003, doi: 10.1088/0953-8984/24/48/485003, Citation: "Now, through high-resolution transmission electron microscopy (HRTEM) a single graphene sheet can be manipulated through electron irradiation. Most importantly for us here, a two-dimensional atomic random network has a special appeal to material scientists. Studies by Kotakoski et al show clear images of small regions of amorphous graphene, characterized by the presence of pentagons and heptagons, as well as hexagons. It should be possible to synthesize amorphous graphene, which our modelling shows is expected to have almost the same areal density as crystalline graphene, by low energy electron beam ‘damage’ to form single freestanding samples that will not pucker or ripple, as they are held under tension by the crystalline graphene surround."
Kurasch, S., Kotakoski, J., Lehtinen, O., Skakalova, V., Smet, J., Krill III, C. E., Krasheninnikov, A. V. & Kaiser, U. (2012), Atom-by-atom observation of grain boundary migration in graphene. Nano letters, 12: 3168-3173, doi: 10.1021/nl301141g, Citation: "Significant changes in the atomic structure of graphene can be induced via bond rotations under 80 kV electron irradiation, as we have previously shown."
Li, Y., & Drabold, D. A. (2012), Symmetry breaking and low energy conformational fluctuations in amorphous graphene. physica status solidi (b), 250: 1012-1019doi: 10.1002/pssb.201248481, Citation: "."
Meyer, J. C., F. Eder, S. Kurasch, V. Skakalova, J. Kotakoski, H.-J. Park, S. Roth, A. Chuvilin, S. Eyhusen, G. Benner, A. V. Krasheninnikov, U. A. Kaiser (2012), Accurate Measurement of Electron Beam Induced Displacement Cross Sections for Single-Layer Graphene. Phys. Rev. Lett., 108: 196102, doi: 10.1103/PhysRevLett.108.196102, Citation: "As a competing mechanism, two monovacancies that are created close to each other may combine and form a stable divacancy (since impacts of energetic electrons can rotate bonds in graphene, it is likely that exposure to the beam increases also the diffusivity of vacancies). In any case, the resulting multivacancy configurations contain only very few undercoordinated carbon atoms, while the 3-coordinated atoms in the reconstructed configurations are expected to have an emission threshold similar to that of an atom in the pristine graphene sheet."
Ng, T. Y., Yeo, J. J., & Liu, Z. S. (2012), A molecular dynamics study of the thermal conductivity of graphene nanoribbons containing dispersed Stone-Thrower-Wales defects. Carbon, 50: 4887-4893, doi: 10.1016/j.carbon.2012.06.017, Citation: "Moreover, it has been theoretically and experimentally shown that STW defects can be created through methods such as ion or electron irradiation."
Ozcelik, V. O., Cahangirov, S., & Ciraci, S. (2012), Epitaxial growth mechanisms of graphene and effects of substrates. Physical Review B, 85: 235456, doi: 10.1103/PhysRevB.85.235456, Citation: "Previous experimental studies have not shown any experimental evidence for the existence of SW defects in graphene. Although such defects can be observed by using tunneling electronmicroscopy (TEM), it was noted in previous studies that experimentally observed images of SW defects in graphene are results of electron beams, which suggests that those defects are artifacts of the measurements."
Partovi-Azar, P., & Namiranian, A. (2012), Stone-Wales defects can cause a metal-semiconductor transition in carbon nanotubes depending on their orientation. Journal of Physics: Condensed Matter, 24: 035301, doi: 1088/0953-8984/24/3/035301, Citation: "An SW defect, which is made by a 90° rotation of a single carbon-carbon bond can be introduced into the system, e.g. by single-electron irradiation."
Robertson, A. W., Allen, C. S., Wu, Y. A., He, K., Olivier, J., Neethling, J., Kirkland, A. I., & Warner, J. H. (2012), Spatial control of defect creation in graphene at the nanoscale. Nature communications, 3: 1144, doi: 10.1038/ncomms2141, Citation: "Electron and ion beam irradiation have been successful in generating defects in carbon nanostructures, such as fullerenes, nanotubes, peapods, and recently graphene. Electron beam irradiation of graphene well above its knock-on damage (KOD) threshold of ~86 keV within an AC-TEM generates defects that can be subsequently imaged, with the electron beam accelerating voltage reduced to below the KOD threshold after defect creation. No further defects in graphene were created under these conditions."
Rodríguez-Manzo, J. A., Krasheninnikov, A. V., & Banhart, F. (2012), Engineering the Atomic Structure of Carbon Nanotubes by a Focused Electron Beam: New Morphologies at the Sub-Nanometer Scale. ChemPhysChem, 13: 2596-2600, doi: 10.1002/cphc.201101000, Citation: "Irradiation with electron energies below the threshold can stimulate structural defects due to bond rotation."
Russo, C. J., & Golovchenko, J. A. (2012), Atom-by-atom nucleation and growth of graphene nanopores. Proceedings of the National Academy of Sciences, 109: 5953-5957, doi: 10.1073/pnas.1119827109, Citation: "Topological defects that do not involve carbon atom removal may also be transiently induced in graphene."
Susi, T., Kotakoski, J., Arenal, R., Kurasch, S., Jiang, H., Skakalova, V., Stephan, O., Krasheninnikov, A. V., Kauppinen, E. S., Kaiser, U. A., & Meyer, J. C. (2012), Atomistic Description of Electron Beam Damage in Nitrogen-Doped Graphene and Single-Walled Carbon Nanotubes. ACS nano, 6: 8837-8846, doi: 10.1021/nn303944f, Citation: "Due to earlier discrepancies between ab initio and tight-binding simulations for noncarbon systems, we used a well established simulation approach at the DFT level of approximation (the interested reader can find more information on the method for example in Kotakoski et al. 2011 and the references therein). Contribute to the discrepancy arise since non-orthogonal displacements of atoms with neighbors of different mass may have lower thresholds, unlike atoms in pristine graphene. Fortunately, the effects of the displacement direction is relatively well understood based on previous studies. Moreover, the two-dimensional projection image of the curved surface makes the interpretation of structure more challenging. Finally particularly inside the tubes damage can anneal before it can be observed."
Tang, C. P., & Xiong, S. J. (2012), A graphene composed of pentagons and octagons. AIP Advances, 2: 042147, doi: 10.1063/1.4768669, Citation: "This stabilizing process can be easily understood from the fact that the vacancy defects induce dangling bonds of two carbon atoms in a hexagon, to be more stable they need to be re-bonded by changing the hexagons to pentagons and leaving the larger empty areas in octagons. In fact, such a reconstruction has been found in experiments. In recent experiments, the researchers used electron irradiation to create different defects on graphene with high-resolution transmission electron microscopy (HRTEM) and investigate the creation and transformation of defects."
Terrones, H., Lv, R., Terrones, M., & Dresselhaus, M. S. (2012), The role of defects and doping in 2D graphene sheets and 1D nanoribbons. Reports on Progress in Physics, 75: 062501, doi: 10.1088/0034-4885/75/6/062501, Citation: "Graphene reconstruction producing heptagons and pentagons to preserve the structural connectivity has been reported and TSW-type defects have also been identified in these systems."
Ugeda, M. M., Brihuega, I., Hiebel, F., Mallet, P., Veuillen, J. Y., Gomez-Rodríguez, J. M., & Yndurain, F. (2012), Electronic and structural characterization of divacancies in irradiated graphene. Physical Review B, 85: 121402, doi: 10.1103/PhysRevB.85.121402, Citation: "Both vacancy-type and SW defects can be artificially created in graphene by electron or ion irradiation and visualized with atomic resolution by high-resolution transmission electron microscopy."
Ukpong, A. M., & Chetty, N. (2012), First principles molecular dynamics study of nitrogen vacancy complexes in boronitrene. Journal of Physics: Condensed Matter, 24: 265002, doi: 10.1088/0953-8984/24/26/265002, Citation: "The defect SW(55-77) has been observed in graphene monolayers."
Wang, Z., Zhou, Y. G., Bang, J., Prange, M. P., Zhang, S. B., & Gao, F. (2012), Modification of Defect Structures in Graphene by Electron Irradiation: ab initio Molecular Dynamics Simulations. Journal of Physical Chemistry C, 116: 16070-16079, doi: 10.1021/jp303905u, Citation: "Recent improvement in transmission electron microscopy (TEM) techniques has shown the possibility of directly imaging the defective structures in graphene and of monitoring their evolution over time. As discussed previously, high-resolution TEM images show that the divacancy structures can transform into each other under electron irradiation and also that these transformations can lead to the divacancy migration. Kotakoski el al. have shown that the displacement threshold energy for atoms in the central part of the reconstructed defects is higher than that for perfect graphene, which explains why defect structures tend to grow into larger amorphous patches instead of collapsing into holes under continuous electron irradiation at low voltages. A typical transformation process at θ = 45, ϕ = 60° with E0 = 17 eV is also shown in this [Figure], and the corresponding transformation occurs with a single bond rotation, as has been observed by Kotakoski el al."
Wilson, M. (2012), Model investigations of network-forming materials. Physical Chemistry Chemical Physics, 14: 12701-12714, doi: 10.1039/C2CP41644A, Citation: "The imaging beam may be utilised in a further interesting manner by increasing its energy in order to disrupt the crystalline structure."
Yamazaki, K., Niitsu, N., Nakamura, K., Kanno, M., & Kono, H. (2012), Electronic Excited State Paths of Stone-Wales Rearrangement in Pyrene: Roles of Conical Intersections. Journal of Physical Chemistry A, 116: 11441-11450, doi: 10.1021/jp306894x, Citation: "Kotakoski et al. contributed to recent computational studies based on tight-binding MD and suggest that Stone−Wales rearrangement (SWR) proceeds through multiple bond breaking and recombination processes, and that 1−2 eV/atom of initial vibrational energy should be added to initiate SWR."
Yeo, J. J., Liu, Z., & Ng, T. Y. (2012), Comparing the effects of dispersed Stone-Thrower-Wales defects and double vacancies on the thermal conductivity of graphene nanoribbons. Nanotechnology, 23: 385702, doi: 10.1088/0957-4484/23/38/385702, Citation: "Iit has been theoretically and experimentally shown that STW defects can be created through methods such as ion irradiation, electron irradiation and scanning tunneling microscopy."
Zan, R., Ramasse, Q. M., Bangert, U., & Novoselov, K. S. (2012), Graphene reknits its holes. Nano letters, 12: 3936-3940, doi: 10.1021/nl300985q, Citation: "Edges in graphene are known to be more unstable even at low voltages; atoms ejected from the edge of this larger neighboring hole may have been captured during the reknitting while the long edge may have reconfigured to accommodate the newly formed material into the usual, energetically favorable honeycomb pattern."
Zhao, S., Xue, J., Wang, Y., & Yan, S. (2012), Effect of SiO2 substrate on the irradiation-assisted manipulation of supported graphene: a molecular dynamics study. Nanotechnology, 23: 285703, doi: 10.1088/0957-4484/23/28/285703, Citation: "It should be noted that the Stone-Wales defects created in the high energy range mainly result from indirect damage, which lead to the ‘nudging’ motion of displaced carbon atoms."
Zhou, A., & Sheng, W. (2012), Abnormal pseudospin-degenerate states in a graphene quantum dot with double vacancy defects. Journal of Applied Physics, 112: 014308-014308, doi: 10.1063/1.4732075, Citation: "The presence of vacancies in graphene is inevitable during electron or ion irradiation process."
Zhu, W., Wang, H., & Yang, W. (2012), Evolution of graphene nanoribbons under low-voltage electron irradiation. Nanoscale, 4: 4555-4561, doi: 10.1039/C2NR30648D, Citation: "No in-lattice atoms were found to be removed. However, in-plane 90° bond rotations were frequently observed to transform four adjacent hexagons into Stone-Wales (SW) defects [Figure]. The gradual nucleation and sudden recovery of SW defect arrays without the removal of in-lattice atoms is different from reconstructions through vacancy defects observed by Kotakoski et al."
Zobelli, A., Ivanovskaya, V., Wagner, P., Suarez-Martinez, I., Yaya, A., & Ewels, C. P. (2012), A comparative study of density functional and density functional tight binding calculations of defects in graphene. physica status solidi (b), 249: 276-282, doi: 10.1002/pssb.201100630, Citation: "The usage of density functional tight binding has been employed in the study of the structure and energetics of point defects in single walled carbon nanotubes."
Kim, Y., Ihm, J., Yoon, E., & Lee, G. D. (2011), Dynamics and stability of divacancy defects in graphene. Physical Review B, 84: 075445, doi: 10.1103/PhysRevB.84.075445, Citation: "The structural change of vacancy defects driven by electron beam was addressed in detail in a very recent paper."
Kotakoski, J., Santos-Cottin, D., & Krasheninnikov, A. V. (2011), Stability of Graphene Edges under Electron Beam: Equilibrium Energetics versus Dynamic Effects. ACS nano, 6: 671-676, doi: 10.1021/nn204148h, Citation: "Displacement Threshold Calculations: In our simulations, we followed a well-established approach repeatedly used to model effects of electron irradiation on solid targets. The energy redistribution affects the displacement threshold, similar to what has been argued for atoms at vacancy defects in otherwise pristine graphene. During the displacement simulations, we observed several structural transformations at the edges. The ZZ->ZZ(57) transformation has earlier been predicted from edge formation energies. However, since the bond rotation barrier in graphene is 5-10 eV, this is unlikely to happen via thermal activation at typical experimental temperatures. However, we observed this transformation via the Stone-Wales mechanism due to an electron impact, similar to what happens in pristine graphene."
Ori, O., Cataldo, F., & Putz, M. V. (2011), Topological Anisotropy of Stone-Wales Waves in Graphenic Fragments. International journal of molecular sciences, 12: 7934-7949, doi: 10.3390/ijms12117934, Citation: "Transmission Electron Microscopy (TEM) detailed measurements point out that the migration and the separation of the pentagon-heptagon pairs does not happen on planar graphene membranes where the 5-7 defects relax back reconstructing the original graphene lattice. These experiments indicate that extended dislocation dipole, favored by the presence of structural strain, preferably appear in curved graphitic structures or systems like CNT or fullerene molecules. We observe that the instrumental role, in curved graphitic structures, of the induced tensile strain in allowing the creation and the diffusion of dislocation dipoles has been recently confirmed by these extended experimental and theoretical studies, stating that SW defects form in graphene with a lower probability than in CNT’s"
Rodrigues, J. N., Goncalves, P. A. D., Rodrigues, N. F. G., Ribeiro, R. M., dos Santos, J. L., & Peres, N. M. R. (2011), Zigzag graphene nanoribbon edge reconstruction with Stone-Wales defects. Physical Review B, 84: 155435, doi: 10.1103/PhysRevB.84.155435, Citation: "The energy barrier for producing a SWdefect in the bulk of graphene is of the order of 5-10 eV."
Kurasch, S., Meyer, J. C., Kunzel, D., Gross, A., & Kaiser, U. (2011). Simulation of bonding effects in HRTEM images of light element materials. Beilstein Journal of Nanotechnology, 2: 394-404, doi: 10.3762/bjnano.2.45. Cited by (1)
Susi, T., Kotakoski, J., Arenal, R., Kurasch, S., Jiang, H., Skakalova, V., Stephan, O., Krasheninnikov, A. V., Kauppinen, E. S., Kaiser, U. A., & Meyer, J. C. (2012), Atomistic Description of Electron Beam Damage in Nitrogen-Doped Graphene and Single-Walled Carbon Nanotubes. ACS nano, 6: 8837-8846, doi: 10.1021/nn303944f, doi: 10.1021/nn303944f, Citation: "The TEM image simulations were based on projections of the electrostatic potential corresponding to the all-electron selfconsistent electron density from the WIEN2k DFT code as described in Kurasch et al. 2011."
Meyer, J. C., S. Kurasch, H. J. Park, V. Skakalova, D. Kunzel, A. Gross, A. Chuvilin, G. Algara-Siller, S. Roth, T. Iwasaki, U. Starke, J. Smet, & U. Kaiser (2011), Experimental analysis of charge redistribution due to chemical bonding by High-resolution transmission electron microscopy. Nature Materials, 10: 209-215, doi: 10.1038/nmat2941. Cited by (67)
Kaiser, U. A. (2013), Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope, Graphene 2013, doi: PDF, Citation: "We investigate in-situ electron beam-induced modifications of graphene functionalized by dopants."
Loffler, S., Motsch, V., & Schattschneider, P. (2013), A pure state decomposition approach of the mixed dynamic form factor for mapping atomic orbitals. Ultramicroscopy, 131: doi: 10.1016/j.ultramic.2013.03.021, Citation: "The possibility to directly map atomic orbitals gives rise to exciting new possibilities like directly studying the electronic structure of defects."
Meyer, J. (2013), New horizons and challenges in the microscopic characterization of 2-D materials, Graphene 2013, PDF, Citation: "Substitutional doping of graphene can be obtained not only via a modified synthesis but also by electron irradiation effects."
Petersen, S. B., Gajula, G. P., & Neves-Petersen, M. T. (2013), Sub-picometer structural information of graphene hidden in a 50pm resolved image. Nanoscale, Advance Article, doi: 10.1039/C3NR00536D, Citation: "."
Waldmann, D., Butz, B., Bauer, S., Englert, J. M., Jobst, J., Ullmann, K., Fromm, F., Ammon, M., Enzelberger, M., Hirsch, A., Maier, S., Schmuki, P., Seyller, T., Spiecker, E., & Weber, H. B. (2013), Robust Graphene Membranes in a Silicon Carbide Frame. ACS nano, doi: 10.1021/nn401037c, Citation: "In particular, high-resolution TEM (HRTEM) is used to study defects, grain boundaries, or the incorporation of dopands into the graphene sheet."
Wang, W. L., & Kaxiras, E. (2013), Efficient calculation of the effective single-particle potential and its application in electron microscopy. Physical Review B, 87: 085103, doi: 10.1103/PhysRevB.87.085103, Citation: "Recent experiments and simulations18 showed that charge redistribution due to bonding plays a significant role in imaging, as for example, in the substitutional defect in graphene, where realistic first-principles methods are required to explain the experimental results."
Yan, H., Liu, C. C., Bai, K. K., Wang, X., Liu, M., Yan, W., Meng, L., Zhang, Y., Liu, Z., Nie, J. C., Yao, Y., & He, L. (2013), Electronic Structures of Graphene Layers on Metal Foil: Effect of Point Defects. arXiv preprint, arXiv, 1302.4807, Citation: "There are various atomic-scale defects, such as heptagon-pentagon topological defects, adatoms, dopants, atomic vacancies in graphene layers."
Zeng, H., Zhao, J., Wei, J., & Leburton, J. P. (2013), Structural Defects on the Electronic Transport Properties of Carbon-Based Nanostructures. In Topological Modelling of Nanostructures and Extended Systems, Carbon Materials: Chemistry and Physics, 7: 77-103, doi: 10.1007/978-94-007-6413-2_3, Citation: "Hence, the predicted extraordinary properties of nitrogen-doped nanomaterials have now been experimentally confirmed and they exhibit the potential applications in electronic nanodevices."
Ahlgren, E. H., Kotakoski, J., Lehtinen, O., & Krasheninnikov, A. V. (2012), Ion irradiation tolerance of graphene as studied by atomistic simulations. Applied Physics Letters, 100: 233108-233108, doi: 10.1063/1.4726053, Citation: "Ion beam can give rise to incorporation of foreign atoms (e.g., nitrogen) as substitutional impurities in graphene membranes."
Araujo, P. T., Terrones, M., & Dresselhaus, M. S. (2012), Defects and impurities in graphene-like materials. Materials Today, 15: 98-109, doi: 10.1016/S1369-7021(12)70045-7, Citation: "In order to understand the effects of the various interesting defects, in graphene-like systems that occur or are intentionally introduced, a variety of experimental probes are used, for instance aberration corrected high-resolution transmission electron microscopy is used. Aberration-corrected AC-HRTEM is highly effective for studying the morphology of carbon based materials. Of course, AC-HRTEM has the advantage of high (atomic scale) resolution so that it provides valuable information about the atomic structure of pristine materials as well as the impurities in defective materials. This technique has the disadvantage of requiring expensive equipment, is time-consuming in operation and, most of time, AC-HRTEM is destructive in the sense that one cannot be assured that the sample will keep its same characteristics before and after the HRTEM analysis. Another drawback of this technique is that it relies on additional complex and dedicated equipment that is needed to extract useful information from the images. AC-HRTEM would be ideal to fully characterize, for example, 5-7-7-5 and 5-8-5 defects in nanocarbons. An interesting application also involving AC-HRTEM is presented by Meyer et al.. They demonstrate an experimental analysis of charge redistribution due to chemical bonding in nitrogen-doped graphene membranes and boron-nitride monolayers [Figure]." Also as PDF.
Batzill, M. (2012), The surface science of graphene: Metal interfaces, CVD synthesis, nanoribbons, chemical modifications, and defects. Surface Science Reports, 67: 83-115, doi: 10.1016/j.surfrep.2011.12.001, Citation: "The charge re-distribution around the N-dopant in graphene has recently been observed by high resolution TEM."
Chamberlain, T. W., J. Biskupek, G. A. Rance, A. Chuvilin, T. J. Alexander, E. Bichoutskaia, U. A. Kaiser, & A. N. Khlobystov (2012a), Size, Structure, and Helical Twist of Graphene Nanoribbons Controlled by Confinement in Carbon Nanotubes. ACS Nano, 6: 3943-3953, doi: 10.1021/nn300137j, Citation: "The other possible edge atoms present in the nanotube (hydrogens) show significantly lower edge contrast [Figure]."
Chisholm, M. F., Duscher, G., & Windl, W. (2012), Oxidation Resistance of Reactive Atoms in Graphene. Nano letters, 12: 4651-4655, doi: 10.1021/nl301952e, Citation: "High-resolution TEM (HRTEM) has been used to look at charge distribution around N atoms in graphene."
Cockayne, E. (2012), Graphing and grafting graphene: Classifying finite topological defects. Physical Review B, 85: 125409, doi: 10.1103/PhysRevB.85.125409, Citation: "The "flower" defect, a topological defect that can be described as the rotation of 24 central atoms in ideal graphene by 30◦ has been identified."
Florea, I., Ersen, O., Arenal, R., Ihiawakrim, D., Messaoudi, C., Chizari, K., .Janowska, I., & Pham-Huu, C. (2012), 3D Analysis of the Morphology and Spatial Distribution of Nitrogen in Nitrogen-Doped Carbon Nanotubes by Energy-Filtered Transmission Electron Microscopy Tomography. Journal of the American Chemical Society, 134: 9672-9680, doi: 10.1021/ja304079d, Citation: "Recently Meyer et al. have studied by HRTEM the nitrogen substitution in graphene."
Gamm, B., Blank, H., Popescu, R., Schneider, R., Beyer, A., Golzhauser, A., & Gerthsen, D. (2012), Quantitative High-Resolution Transmission Electron Microscopy of Single Atoms. Microscopy and Microanalysis, 18: 212-217, doi: 10.1017/S1431927611012232, Citation: "."
Haigh, S. J., Gholinia, A., Jalil, R., Romani, S., Britnell, L., Elias, D. C., Novoseov, K. S, Ponomarenko, L. A., Geim, A. K., & Gorbachev, R. (2012), Cross-sectional imaging of individual layers and buried interfaces of graphene-based heterostructures and superlattices. Nature Materials, doi: 10.1038/nmat3386, Citation: "Top view TEM of graphene and boron nitride monolayers has allowed visualization and analysis of various types of defects including ripples, vacancies, substitutional atoms, adatoms, grain boundaries and edges."
Holmstrom, E., Kotakoski, J., Lechner, L., Kaiser, U., & Nordlund, K. (2012), Atomic-scale effects behind structural instabilities in Si lamellae during ion beam thinning. AIP Advances, 2: 012186, doi: 10.1063/1.3698411, Citation: "The current development in AC-HRTEM is to lower the voltage from the usual 200-300 kV to well below 100 kV, in order to minimize displacement damage in fragile samples. So far, predominantly low-dimensional materials such as graphene have been studied at low electron beam voltages by HRTEM."
Huang, P. Y., Meyer, J. C., & Muller, D. A. (2012), From atoms to grains: Transmission electron microscopy of graphene. MRS bulletin, 37: 1214-1221, doi: 10.1557/mrs.2012.183, Citation: "In addition to atomic structure, local image contrast in (S)TEM depends on the nuclear potential of the atoms, making TEM and especially STEM sensitive to atomic number. This sensitivity enables identification of even single-atom substitutions like nitrogen dopants in two-dimensional materials. Combining electron energy-loss spectroscopy (EELS) with (S)TEM provides local and spatially varying measurements of the atomic and electronic confi gurations of a sample. In two-dimensional materials, insights into the electronic configurations can also be obtained from HRTEM images. [Figure] shows the first direct visualization of nitrogen dopants in graphene."
Joucken, F., Tison, Y., Lagoute, J., Dumont, J., Cabosart, D., Zheng, B., Repain, V., Chacon, C., Girard, Y., Botello-Mendez, A. R., Rousset, S., Sporken, R., Charlier, J. C., & Henrard, L. (2012), Localized state and charge transfer in nitrogen-doped graphene. Physical Review B, 85: 161408, doi: 10.1103/PhysRevB.85.161408, Citation: "The synthesis of chemically modified graphene has been achieved by direct growth of modified layers."
Kaiser, U. A. (2012), Low-voltage TEM-current status and future prospects. EMC 2012, PDF, Citation: "We visualize bonding effects in high-resolution TEM images of covalently bonded light elements (B, C, N)."
Kaiser, U. A. (2012), Low-Voltage TEM to explore physics and chemistry of low-dimensional and low-atomic number materials on the atomic scale, Graphene Conference 2012, doi: PDF, Citation: "We visualize bonding effects in high-resolution TEM images of covalently bonded light elements (B, C, N)."
Komsa, H. P., Kotakoski, J., Kurasch, S., Lehtinen, O., Kaiser, U., & Krasheninnikov, A. V. (2012), Two-dimensional transition metal dichalcogenides under electron irradiation: defect production and doping. Physical Review Letters, 109: 035503, doi: 10.1103/PhysRevLett.109.035503, Citation: "Characterization of the h-BN samples has extensively been carried out using high resolution transmission electron microscopy (HR-TEM). During imaging, however, energetic electrons in the TEM can give rise to production of defects due to ballistic displacements of atoms from the sample and beam stimulated chemical etching, as studies on h-BN membranes also indicate."
Kondo, T., Casolo, S., Suzuki, T., Shikano, T., Sakurai, M., Harada, Y., Saito, M., Oshima, M., Trioni, M. I., Tantardini, G. F., & Nakamura, J. (2012), Atomic-scale characterization of nitrogen-doped graphite: Effects of dopant nitrogen on the local electronic structure of the surrounding carbon atoms. Physical Review B, 86: 035436, doi: 10.1103/PhysRevB.86.035436, Citation: "The positively charged N of graphitic-N has also been reported recently based on theoretical results by Meyer et al."
Krivanek, O. L., Zhou, W., Chisholm, M. F., Idrobo, J. C., Lovejoy, T. C., Ramasse, Q. M., & Dellby, N. (2012), Gentle STEM of single atoms: Low keV imaging and analysis at ultimate detection limits. Low Voltage Electron Microscopy: Principles and Applications, 6: 119-161, doi: 10.1002/9781118498514.ch6, Citation: "."
Kurasch, S., Huang, P. Y., Kotakoski, J., Krasheninnikov, A. V., Hovden, R., Mao, Q., Meyer, J. C., Muller, D. A., & Kaiser, U. A. (2012) Atomic scale imaging and spectroscopy of 2D silica glass on graphene, EMC 2012, doi: PDF, Citation: "This has resulted in a huge variety of recent scientific studies that would have been impossible to think about before, such as the detection of charge redistribution due to chemical bonding in direct HRTEM images."
Kurasch, S., Kotakoski, J., Lehtinen, O., Skakalova, V., Smet, J., Krill III, C. E., Krasheninnikov, A. V., & Kaiser, U. (2012), Atom-by-atom observation of grain boundary migration in graphene. Nano letters, 12: 3168-3173, doi: 10.1021/nl301141g, Citation: "The simulated atomic configuration presented in [Figure] eventually transforms into a flowerlike structure. This hexagon-shaped grain (flower defect) has been reported previously in nitrogen-doped graphene. For TEM-imaging, the spherical aberration has been set to 20 μm, and images were recorded at a Scherzer defocus of approximately −9 nm. Under these conditions, atoms appear dark. The resulting image sequences were background subtracted and drift compensated."
Kyle, J. R. (2012), Industrial graphene metrology. Nanoscale, 4: 3807-3819, doi: 10.1039/C2NR30093A, Citation: "TEM can reveal charge-transport effects of doping in graphene. Combining image processing techniques with TEM imaging has enabled the effect of nitrogen doping on CVD graphene to be studied. Frequency filtering enhanced the atomic contrast of graphene in TEM images. Moreover, Meyer et al. 2011 have used XPS techniques."
Lee, Z., Meyer, J. C., Rose, H., & Kaiser, U. (2012), Optimum HRTEM image contrast at 20 kV and 80 kV—Exemplified by graphene. Ultramicroscopy, 112: 39-46, doi: 10.1016/j.ultramic.2011.10.009, Citation: "The recent development of new preparation methods enables production of large area single-layer and bi-layer graphene of high quality. Therefore, basic TEM studies of defects in graphene can now be performed. Moreover, we can calculate the projected atom potential based on DFT calculations."
Linck, M. (2012), Optimum Aberration Coefficients for Recording High-Resolution Off-Axis Holograms in a Cs-corrected TEM. Ultramicroscopy, doi: 10.1016/j.ultramic.2012.08.006, Citation: "Recent studies, especially in the field of carbon based materials, emphasize the importance of very high phase sensitivity."
Lu, J., Gao, S. P., & Yuan, J. (2012), ELNES for boron, carbon, and nitrogen K-edges with different chemical environments in layered materials studied by density functional theory. Ultramicroscopy, 112: 61-68, doi: 10.1016/j.ultramic.2011.10.011, Citation: "Graphene doped with nitrogen shows interesting properties and has been studied by transmission electron microscopy (TEM)."
Lu, W., Barbosa, R., Clarke, E., Eyink, K., Grazulis, L., Mitchel, W. C., & Boeckl, J. J. (2012), Interface Oxidative Structural Transitions in Graphene Growth on SiC (0001). Journal of Physical Chemistry C, 116: 15342-15347, doi: 10.1021/jp301996h, Citation: "The contrast changes in the TEM images are often considered to be a result of charged defects and/or an electronic charge density induced by chemical reactions with foreign atoms. The detailed interpretation and analysis of the contrast changes in TEM are complicated."
Lv, R., & Terrones, M. (2012), Towards new graphene materials: doped graphene sheets and nanoribbons. Materials Letters, 78: 209-218, doi: 10.1016/j.matlet.2012.04.033, Citation: "High-resolution transmission electronmicroscopy (HRTEM) is used to visualize individual atomic dopants within the graphene lattice. The nitrogen substitutions exhibit a weak dark contrast in the larger defocus HRTEMimages, as shown in [Figure]."
Lv, R., Li, Q., Botello-Mendez, A. R., Hayashi, T., Wang, B., Berkdemir, A., Hao, Q., Elias, A. L., Cruz-Silva, R., Gutierrez, H. R., Kim, Y. A., Muramatsu, H., Zhu, J., Endo, M., Terrones, H., Charlier, J. C., Pan, M., & Terrones, M. (2012), Nitrogen-doped graphene: beyond single substitution and enhanced molecular sensing. Scientific reports, 2: 586, doi: 10.1038/srep00586, Citation: "Substitutional doping of graphene with different atoms (e.g. B, N, S and Si) results in the disruption of the ideal sp2 hybridization of the carbon atoms, thus locally inducing significant changes in their electronic properties and chemical reactivity."
Meyer, J. C., F. Eder, S. Kurasch, V. Skakalova, J. Kotakoski, H.-J. Park, S. Roth, A. Chuvilin, S. Eyhusen, G. Benner, A. V. Krasheninnikov, U. A. Kaiser (2012), Accurate Measurement of Electron Beam Induced Displacement Cross Sections for Single-Layer Graphene. Phys. Rev. Lett., 108: 196102, doi: 10.1103/PhysRevLett.108.196102, Citation: "The need for high doses is further increased for new techniques such as the analysis of charge distributions from very high signal-to-noise ratio HRTEM images. Under 80 keV electron irradiation, the defect free graphene lattice remains undisturbed up to very high doses."
Odlyzko, M. L., & Mkhoyan, K. A. (2012), Identifying Hexagonal Boron Nitride Monolayers by Transmission Electron Microscopy. Microscopy and Microanalysis, 18: 558, doi: 10.1017/S143192761200013X, Citation: "Studies on h-BN have employed BF-CTEM imaging. Employing monochromated illumination together with carefully tuned defocus and an appropriate objective aperture, it is possible to obtain a high-resolution aberrationcorrected BF-CTEM image without a sign reversal in the CTF, which in turn could permit identification of monolayer h-BN from a raw tilt series similarly as from a tilt series of ADF-STEM images. However, this is not standard experimental practice and is very difficult to implement given the exacting required conditions and the high sensitivity of CTF structure to defocus."
Picher, M., Navas, H., Arenal, R., Quesnel, E., Anglaret, E., & Jourdain, V. (2012), Influence of the growth conditions on the defect density of single-walled carbon nanotubes. Carbon, 50: 2407-2416, doi: 10.1016/j.carbon.2012.01.055, Citation: "However, the presence of additional compounds (water, oxygen, hydrogen. . .) present as additives, by-products or contaminants may promote the creation of defects at high-temperature. For instance, nitrogen-substitution is observed when growing graphene or carbon nanotubes in presence of NH3."
Reiber Kyle, J. L. (2012), Multi-Scale Optical Metrology of Biomaterials and Nanomaterials for Medical and Industrial Applications, PhD Dissertation University of California, PDF, Citation: "TEM has been used to reveal charge-transport effects of doping. Combining image processing techniques with TEM imaging has enabled the effect of nitrogen doping on CVD graphene to be studied. Frequency filtering enhanced the atomic contrast of graphene in TEM images."
Su, P., Guo, H., Peng, S., & Ning, S. (2012), Preparation of nitrogen-doped graphene and its supercapacitive properties. Acta Physico-Chimica Sinica, 28: 2745-2753, only in Chinese
Suenaga, K., Kobayashi, H., & Koshino, M. (2012), Core-level spectroscopy of point defects in single layer h-BN. Physical Review Letters, 108: 075501, doi: 10.1103/PhysRevLett.108.075501, Citation: "This is a great step further beyond the previous report showing the chemical analysis of h-BN by the simple ADF intensities or phase contrast."
Susi, T., Kotakoski, J., Arenal, R., Kurasch, S., Jiang, H., Skakalova, V., Stephan, O., Krasheninnikov, A. V., Kauppinen, E. I., Kaiser, U. A., & Meyer, J. C. (2012), Atomistic Description of Electron Beam Damage in Nitrogen-Doped Graphene and Single-Walled Carbon Nanotubes. ACS nano, 6: 8837-8846, doi: 10.1021/nn303944f, Citation: "Nitrogen-doped graphene (N-graphene) has attracted increasing attention more recently. Cutting-edge developments in instrumentation have enabled atom-by-atom analysis of graphene and similar materials and even direct imaging of nitrogen sites. Recent experiments employing aberration-corrected (AC) electron optics for high-resolution TEM (HRTEM) have shown that N-graphene grown by chemical vapor deposition (CVD) remains stable under such conditions for long exposure times and correspondingly high doses. We directly image these events by 80 kV atomic-resolution AC-HRTEM of N-graphene, which initially shows only nitrogen substitutions, in agreement with previous studies. The N-graphene samples had regions of monolayer and few-layer graphene. Moreover, contrary to the widely used independent atom model, atomic potentials derived from all-electron DFT calculations show that electron scattering on the carbon atom next to a nitrogen differs appreciably from electron scattering on a carbon atom elsewhere in the graphene sheet. Thus N substitutions can be directly detected in correctly defocused TEM images as three darker bonds surrounding a central atom, identified as nitrogen by DFT image simulations. This methodology is described in detail in Meyer et al. 2011. From [Figure], it can be directly seen that, instead of the dopant atom, the first atom displaced by the electron beam is one of the three carbon atoms next to it, in agreement with our calculations.
Terrones, H., Lv, R., Terrones, M., & Dresselhaus, M. S. (2012), The role of defects and doping in 2D graphene sheets and 1D nanoribbons. Reports on Progress in Physics, 75: 062501, doi: 10.1088/0034-4885/75/6/062501, Citation: "Experimental work on Nitrogen-doped graphene (NG) synthesis to produce ≥1 layer by CVD on Ni (300 nm) or Cu (300 nm) on silicon wafer from CH4 and NH3 presurcors and with the growth parameters 980 °C / 3 min (fur Ni), 980 °C / 20 min (for Cu)."
Ukpong, A. M., & Chetty, N. (2012), First principles molecular dynamics study of nitrogen vacancy complexes in boronitrene. Journal of Physics: Condensed Matter, 24: 265002, doi: 10.1088/0953-8984/24/26/265002, Citation: "Several attempts have been made to synthesize hybrid BCN nanostructures."
Ukpong, A. M., & Chetty, N. (2012), Half-metallic ferromagnetism in substitutionally doped boronitrene. Physical Review B, 86: 195409, doi: 10.1103/PhysRevB.86.195409, Citation: "BCN monolayers possess tunable magnetoelectronic properties that depend on the relative concentrations of the constituent species."
Urban, K. W., Barthel, J., Houben, L., Jia, C. L., Lentzen, M., Thust, A., & Tillmann, K. (2012), Ultrahigh-Resolution Transmission Electron Microscopy at Negative Spherical Aberration. Handbook of Nanoscopy Volume 1&2, Chapter 3: 81-107, doi: 10.1002/9783527641864.ch3, Citation: "."
Wang, W. L., Bhandari, S., Yi, W., Bell, D. C., Westervelt, R., & Kaxiras, E. (2012), Direct Imaging of Atomic-Scale Ripples in Few-Layer Graphene. Nano letters, 12: 2278-2282, doi: 10.1021/nl300071y, Citation: "The independent atom model superimposes single atomic potentials in the system and neglects all bonding effects, including the redistribution of electronic charge and the corresponding changes in the total potential. The difference may be insignificant in traditional TEM where substantial spherical aberration is present. However, for analyses based on aberration-corrected images, the error may lead to quantitatively or even qualitatively wrong results. To account for bonding effects on the total potential, realistic first-principles methods based on, for example, density functional theory (DFT) must be used. Most efficient DFT codes utilize pseudopotentials and therefore yield wrong total potential in the core region. To remedy this issue, all-electron codes can be used."
Warner, J. H., Margine, E. R., Mukai, M., Robertson, A. W., Giustino, F., & Kirkland, A. I. (2012), Dislocation-driven deformations in graphene. Science, 337: 209-212, doi: 10.1126/science.1217529, Citation: "Low-voltage transmission electron microscopy (TEM) can resolve the lattice structure of carbonbased materials such as graphitic nanomaterials and graphene with high contrast and minimal damage."
Warner, J. H., Mukai, M., & Kirkland, A. I. (2012), Atomic Structure of ABC Rhombohedral Stacked Trilayer Graphene. ACS nano, 6: 5680-5686, doi: 10.1021/nn3017926, Citation: "Typical HRTEM images obtained without the use of a monochromator are of similar standard to those previously reported in the literature, in terms of ability to resolve individual carbon atoms and show contrast reversal at the monolayerbilayer step edge."
Yu, J. S., Ha, D. H., & Kim, J. H. (2012), Mapping of the atomic lattice orientation of a graphite flake using macroscopic liquid crystal texture. Nanotechnology, 23: 395704, doi: 10.1088/0957-4484/23/39/395704, Citation: "The determination of edge type is an important issue in practice. It is very difficult to observe them, and this is possible only using sophisticated and expensive tools such as high-resolution transmission electron microscopy (HRTEM)."
Zeng, H., Zhao, J., Wei, J., & Xu, D. (2012), Role of nitrogen distribution in asymmetric Stone-Wales defects on electronic transport of graphene nanoribbons. physica status solidi (b), 249: 128-133, doi: 10.1002/pssb.201147371, Citation: "The predicted extraordinary properties of nitrogen-doped nanomaterials have now been experimentally confirmed and they exhibit the potential applications in electronic nanodevices."
Zhou, W., Kapetanakis, M. D., Prange, M. P., Pantelides, S. T., Pennycook, S. J., & Idrobo, J. C. (2012), Direct Determination of the Chemical Bonding of Individual Impurities in Graphene. Physical review letters, 109: 206803, doi: 10.1103/PhysRevLett.109.206803, Citation: "High resolution transmission electron microscopy (TEM) imaging, supplemented by density functional theory (DFT) calculations, can provide evidence of charge redistribution in two-dimensional materials at the single-atom level."
Zhu, Y., & Wu, L. (2012), Shadow Imaging for Charge Distribution Analysis. NATO Science for Peace and Security Series B: Physics and Biophysics: 381-388, doi: 10.1007/978-94-007-5580-2_35, Citation: "Imaging of N impurities in graphene Via DFT calculation and image simulation [Figure]."
Zoberbier, T., Chamberlain, T. W., Biskupek, J., Kuganathan, N., Eyhusen, S., Bichoutskaia, E., Kaiser, U. A., & Khlobystov, A. N. (2012), Interactions and reactions of transition metal clusters with the interior of single-walled carbon nanotubes imaged at the atomic scale. Journal of the American Chemical Society, 134: 3073-3079, doi: 10.1021/ja208746z, Citation: "The capability of high resolution TEM for imaging electron density distribution in structures has recently been demonstrated."
Berseneva, N., Krasheninnikov, A. V., & Nieminen, R. M. (2011), Mechanisms of Postsynthesis Doping of Boron Nitride Nanostructures with Carbon from First-Principles Simulations. Physical Review Letters, 107: 035501, doi: 10.1103/PhysRevLett.107.035501, Citation: "Numerous attempts to manufacture graphene with nitrogen or boron dopants have indeed been made. Note that C atoms in graphene sheets are sometimes substituted with N atoms in a TEM."
Chuvilin A. , E. Bichoutskaia, M. C. Gimenez-Lopez, T. W. Chamberlain, G. A. Rance, N. Kuganathan, J. Biskupek, U. A. Kaiser & A. N. Khlobystov (2011), Self-assembly of a sulphur-terminated graphene nanoribbon within a single-walled carbon nanotube. Nature Materials, 10: 687-692, doi: 10.1038/NMAT3082, Citation: "The single-atom contrast of N and O will be much lower than S and indistinguishable from that of C."
Ciston, J., Kim, J. S., Haigh, S. J., Kirkland, A. I., & Marks, L. D. (2011). Optimized conditions for imaging the effects of bonding charge density in electron microscopy. Ultramicroscopy, 111: 901-911, doi: 10.1016/j.ultramic.2010.12.003, Citation: "Despite this experimental challenge, local bonding effects have recently been resolved for monolayer BN in HREM images by Meyer et al. 2011 wherein bonding contributions were confirmed both experimentally and computationally to contribute as much as 10% to the single pixel contrast at the N site. The spatially averaged contrast contribution over the entire image computed from the DFT and IAM curves in [Figure] is 0.9%, which is consistent with our maximum simulated value of 1.2%"
Cockayne, E., Rutter, G. M., Guisinger, N. P., Crain, J. N., First, P. N., & Stroscio, J. A. (2011), Grain boundary loops in graphene. Physical Review B, 83: 195425, doi: 10.1103/PhysRevB.83.195425, Citation: "The flower defect was discovered independently by transmission electron microscopy on graphene deposited by chemical vapor deposition on Ni."
Trendbericht (2012), Festkorperchemie 2011. (only in German) Nachrichten aus der Chemie. 60: 251-264, doi: 10.1515/nachrchem.2012.60.3.251 (only in German), Citation: "New possibilities of transmission electron microscopy (TEM) were demonstrated. The cited publication is devoted to N-doped graphene. This material has recently gained some importance for applications in fuel cells, batteries, and catalysis, although many of the fundamental properties are still far from understood. The group led by Kaiser describes how with a combination of HRTEM experiments and ab initio electronic structure calculations electronic states at point defects, other non-periodic arrays and nanoscale objects can be examined, which are not accessible by electron or X-ray diffraction experiments. As an example, N-substituted graphene and hexagonal boron nitride (hBN) were studied and the experimentally observed differences in contrast in the TEM image were assigned to the specific details in the simulated electron distribution. With this method, the substitution of an atom in graphene can be proven [Figure]. However, such an analysis also raises the demands on the material under investigation. So it should be very stable under the electron beam to allow long exposure times, which are essential for a good signal-to-noise ratio. Furthermore, a well-defined and ultra-thin sample geometry for the complex and precise analysis is necessary."
Guo, B., Fang, L., Zhang, B., & Gong, J. R. (2011), Graphene doping: A review. Insciences Journal, 1: 80-89, doi: 10.5640/insc.010280, Citation: ""The outstanding message of the analysis by Meyer et al. 2011 is that the detailed view of BN and N-doped graphene shows the potential of high-resolution electron microscopy to study the electronic configuration and the charge distribution." and the authors said further "that the study of N-doped graphene is helpful to understand the impact of the integration of hetero atoms in graphene on the local electronic properties. The structure of inorganic and organic materials can now be calculated by means of DFT quantum-physical modelling to obtain their exact physical properties from AC-TEM measurements."
Jinschek, J. R., Yucelen, E., Freitag, B., Calderon, H. A., & Steinbach, A. (2011), Still "Plenty of Room at the Bottom" for Aberration-Corrected TEM. Microscopy Today, 19: 10-14, doi: 10.1017/S155192951100023X, Citation: "."
Kurasch, S., Meyer, J. C., Kunzel, D., Gross, A., & Kaiser, U. (2011), Simulation of bonding effects in HRTEM images of light element materials. Beilstein journal of nanotechnology, 2: 394-404, doi: 10.3762/bjnano.2.45, Citation: "Due to improvements in specimen quality, for the first time, we were able to measure the influence of charge redistribution on the HRTEM image contrast experimentally for two different materials, namely nitrogen doped graphene and singlelayer hexagonal boron nitride. HRTEM image simulation including chemical bonding using DFT based scattering potentials has been applied. The relaxation structure models obtained using the very fast and efficient pseudopotential DFT code VASP are shown in this [Figure]. Details on the relaxation process can be found in the supplementary information of Meyer et al. 2011. Moreover, the relative changes for the single atom nitrogen substitution are found. For nitrogen, the increase of the contrast due to charging enables the detection whereas for oxygen this increase disables the detection. On the contrary, the decrease of the boron contrast simplifies the detection because the relative contrast difference to the carbon lattice is increased from 5% in the neutral to 9% in the bonded configuration, where only the latter is significantly above the experimental accuracy of 3%."
Liu, J. J. (2011), Advanced electron microscopy of metal-support Interactions in supported metal catalysts. ChemCatChem, 3: 934-948, doi: 10.1002/cctc.201100090, Citation: "The recent demonstration by Meyer et al. 2011 of atomic level imaging of charge redistribution, due to chemical bonding, on the example of N-doped graphene is very encouraging. Since charge transfer across interfaces and change of work function greatly affect the emission of secondary electrons it is plausible that (energy-filtered) secondary electron imaging with sub-nanometer or atomic resolution can provide information on the local patch field or the change in work function of the exposed surfaces, which in turn affect the Schottky barrier formed at the metal–oxide interface."
Ori, O., Cataldo, F., & Putz, M. V. (2011), Topological Anisotropy of Stone-Wales Waves in Graphenic Fragments. International journal of molecular sciences, 12: 7934-7949, doi: 10.3390/ijms12117934, Citation: "In epitaxial graphene grown at high temperatures on mechanically-polished SiC(0001), a characteristic 6-fold "flower" defect results from STM measures."
Lehtinen, O. (2011), Irradiation effects in graphene and related materials, PhD Dissertation University of Helsinki, doi: PDF, Citation: "In reality, the situation is not this simple, and often the nature of the bonds between atoms cannot be assigned in such strict categories. Boron nitride is an example of such a material. The crystal structures similar to carbon seem to imply covalent bonding between the constituent atoms, but on the other hand experiments and electronic structure calculations show that the valence electrons are in fact strongly localized around the nitrogen atoms. Moreover, due to the lower mass of boron, its is more probable to displace a boron atom than nitrogen by electron irradiation, but the probabilities are so close to each other that they cannot explain the strong asymmetry observed in experiments. However, those calculations were based on the tight binding approximation, which does not take the signiffcant charge transfer in the 'ionic' h-BN into account and, in fact, the more sophisticated DFT calculations had the relationship of the Td values reversed."
Thomas, J. M., & Midgley, P. A. (2011), The modern electron microscope: A cornucopia of chemico-physical insights. Chemical Physics, 385: 1-10, doi: 10.1016/j.chemphys.2011.04.023, Citation: "The recent paper by Meyer et al. illustrates how, with careful image analysis, it is possible using AC-TEM to distinguish image contrast the origin of which can be attributed to the redistribution of charge around a N defect in graphene; they demonstrate also the ionic character of the B-N bond in hexagonal BN."
Urban, K. W. (2011), Electron microscopy: The challenges of graphene. Nature materials, 10: 165-166, doi: 10.1038/nmat2964, Citation: "An excellent example is provided by the work of Jannik Meyer and colleagues, who studied nitrogen doping of graphene, as reported in Nature Materials1. They provide experimental evidence for strong chemicalbonding- induced charge transfer from the carbon atoms into the region of the bond with the neighbouring nitrogen atom. Meyer et al. have demonstrated another leap forward in the contributions that HRTEM can make to our understanding of graphene’s properties. Specifically, they used density-functional theory (DFT) to calculate the expected electron density around the nitrogen atom and used it to predict the atomic scattering potential for the electrons. The work of Meyer et al. adds the transmission electron microscope equipped with state-of-the-art aberration-corrected electron optics to the list analyse electron bonds. Beyond this specific and important result, the work by Meyer et al. carries a message that electron microscopists should embrace fully if they want to take advantage of the new frontiers opened up by aberration-corrected electron optics: they have to reconsider two hitherto universally employed concepts: the Independent Atom Model (IAM) and the assumption of the ‘ideally weak object’."
Wang, H., Wang, Q., Cheng, Y., Li, K., Yao, Y., Zhang, Q., Dong, C., Wang, P., Schwingenschlogl, U., Yang, W., & Zhang, X. X. (2011), Doping monolayer graphene with single atom substitutions. Nano letters, 12: 141-144, doi: 10.1021/nl2031629, Citation: "Much effort has been devoted to N or B doping either during graphene synthesis or by post annealing in environment with N- or B-containing species."
Westenfelder, B., Meyer, J. C., Biskupek, J., Kurasch, S., Scholz, F., Krill III, C. E., & Kaiser, U. (2011), Transformations of carbon adsorbates on graphene substrates under extreme heat. Nano letters, 11: 5123-5127, doi: 10.1021/nl203224z, Citation: "It is now possible to obtain atomic-resolution images even of light-element materials, with a reduction in radiation damage effected by the utilization of reduced acceleration voltages."
Yuan, Q., Gao, J., Shu, H., Zhao, J., Chen, X., & Ding, F. (2011), Magic Carbon Clusters in the Chemical Vapor Deposition (CVD) Growth of Graphene, Journal of the American Chemical Society, 134: 2970-2975, doi: 10.1021/ja2050875, Citation: "Grain boundary loops have been experimentally observed in graphene."
Zhao, L., He, R., Rim, K. T., Schiros, T., Kim, K. S., Zhou, H., Gutierrez, C., Chockalingam, S. P., Arguello, C., J. & Pasupathy, A. N. (2011), Visualizing individual nitrogen dopants in monolayer graphene. Science, 333: 999-1003, doi: 10.1126/science.1208759, Citation: "Transmission electron microscopy has been used to analyze the effect of the doping process in graphene."
Pacile, D., J. C. Meyer, A. F. Rodriguez, M. Papagno, C. Gomez-Navarro , R. S. Sundaram, M. Burghard, K. Kern, C. Carbone, U. A. Kaiser (2011), Electronic properties and atomic structure of graphene oxide membranes. Carbon, 49: 966-972, doi: 10.1016/j.carbon.2010.09.063 . Cited by (25)
Jeong, H. K., Hong, L., Zhang, X., Vega, E., & Dowben, P. A. (2013), Evidence of band bending and surface Fermi level pinning in graphite oxide. Carbon, 57, doi: 10.1016/j.carbon.2013.01.067, Citation: "Recently the valence band electronic structure of GO has been reported, providing some insight into the role of oxygen bonding."
Kumarasinghe, A. R., Samaranayake, L., Bondino, F., Magnano, E., Kottegoda, N., Carlino, E., Ratnayake, U. N., de Alwis, A. A. P., Karunaratne, V., & Amaratunge, G. A. (2013), Self-Assembled Multilayer Graphene Oxide Membrane and Carbon Nanotubes Synthesized Using a Rare Form of Natural Graphite. Journal of Physical Chemistry C, 117: 9507-9519, doi: 10.1021/jp402428j, Citation: "Due to an open cage around the absorbing atom when the polarization of light would select atoms above and below the graphene plane, high energy features of the C K edge spectrum are suppressed."
Milowska, K. Z., & Majewski, J. A. (2013), Stability and electronic structure of covalently functionalized graphene layers. arXiv preprint, arXiv, doi: 1301.3954, Citation: "Graphene layers (GLs) are emerging as the very promising candidates for a new generation of electronic devices."
Okotrub, A. V., Yudanov, N. F., Asanov, I. P., Vyalikh, D. V., & Bulusheva, L. G. (2013), Anisotropy of Chemical Bonding in Semifluorinated Graphite C2F Revealed with Angle-Resolved X-ray Absorption Spectroscopy. ACS nano, 7: 65-74, doi: 10.1021/nn305268b, Citation: "However, the much stronger changes in the spectra are characteristic for anisotropic materials possessing a π system, such as hexagonal BN."
Wang, H., & Dai, H. (2013), Strongly coupled inorganic-nano-carbon hybrid materials for energy storage. Chemical Society Reviews, 42: 3088-3113, doi: 10.1039/C2CS35307E, Citation: "The atomic structure of GO has been imaged by aberration corrected TEM. A GO sheet typically contains disordered domains with functional groups, relatively ordered graphitic domains and regions with holes and other defects [Figure]."
Chen, D., Feng, H., & Li, J. (2012), Graphene Oxide: Preparation, Functionalization, and Electrochemical Applications. Chemical Reviews, 112: 6027-6053, doi: 10.1021/cr300115g, Citation: "Recently, the direct imaging of lattice atoms and topological defects in single-layer GO has been achieved using high resolution transmission electron microscopy (HRTEM). The chemical composition of GO and the oxygen functional groups in GO have been identified using X-ray absorption near-edge spectroscopy (XANES). The typical O K-edge XANES spectrum of GO shows several distinctive absorption peaks at 531.5, 534.0, 535.5. 540.0, 542.0, and 544.5 eV. These have been assigned to π*(CO), π*(C−O), σ*(O−H), σ*(C−O), σ*(CO), and σ*(CO), respectively."
Ilki, B., Petrovska, S., Sergiienko, R., Tomai, T., Shibata, E., Nakamura, T., Itaru, H., & Zaulychnyy, Y. (2012), X-Ray Emission Spectra of Graphene Nanosheets. Journal of Nanoscience and Nanotechnology, 12: 8913-8919, doi: 10.1166/jnn.2012.6787, Citation: "."
Lee, V., Dennis, R. V., Jaye, C., Wang, X., Fischer, D. A., Cartwright, A. N., & Banerjee, S. (2012), In situ near-edge x-ray absorption fine structure spectroscopy investigation of the thermal defunctionalization of graphene oxide. Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, 30: 061206, doi: 10.1116/1.4766325, Citation: "."
Lee, V., Dennis, R. V., Schultz, B. J., Jaye, C., Fischer, D. A., & Banerjee, S. (2012), Soft X-ray Absorption Spectroscopy Studies of the Electronic Structure Recovery of Graphene Oxide upon Chemical Defunctionalization. Journal of Physical Chemistry C, 116: 20591-20599, doi: 10.1021/jp306497f, Citation: "The O K-edge spectra are characterized by two well-separated sets of absorption features at ∼531.5 and ∼538 eV. The feature at ∼531.5 eV can be attributed to transitions from O 1s core level electrons to π* C-O states derived from carboxylic acid and ketone groups at the GO edge sites. The feature centered at ∼538 eV can be attributed to several transitions including to O−H, C−O, and C-O states of σ* symmetry."
Mai, Y. J., Tu, J. P., Gu, C. D., & Wang, X. L. (2012), Graphene anchored with nickel nanoparticles as a high-performance anode material for lithium ion batteries. Journal of Power Sources, 209: 1-6, doi: 10.1016/j.jpowsour.2012.02.073, Citation: "Recently, defects of GO and graphene, which originate from the oxidation-reduction treatment, have been directly observed by atomic resolution TEM. Previous reports demonstrated that there are many defects on the surface of GO and graphene obtained by oxidation-reduction treatment."
Mao, S., Pu, H., & Chen, J. (2012), Graphene oxide and its reduction: modeling and experimental progress. RSC Advances, 2: 2643-2662, doi: 10.1039/C2RA00663D, Citation: "Near-edge X-ray absorption fine structure (NEXAFS) for the O-K edge suggested that the carbonyls in GO are arranged on the carbon layer on average, and there is locally ordered structure from some oxygenated functional groups."
Maratkanova, A. N., Syugaev, A. V., Shakov, A. A., Vilkov, O. Y., & Lomayeva, S. F. (2012), Thin Organic Layers Grown on the Surface of Iron Particles under High-Energy Ball Milling in the Presence of Polystyrene and Various Surfactants: X-ray Absorption and Photoelectron Spectroscopy Studies. Journal of Physical Chemistry C, 116: 14005-14013, doi: 10.1021/jp302788s, Citation: "Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy has become a powerful tool to probe electronic and structural properties of new materials."
Milowska, K., Birowska, M., & Majewski, J. A. (2012), Mechanical and electrical properties of carbon nanotubes and graphene layers functionalized with amines. Diamond and Related Materials, 23: 167-171, doi: 10.1016/j.diamond.2011.12.032, Citation: "Nowadays graphene layers are emerging as the very promising candidate for a new generation of electronic devices."
Nair, R. R., Wu, H. A., Jayaram, P. N., Grigorieva, I. V., & Geim, A. K. (2012), Unimpeded permeation of water through helium-leak-tight graphene-based membranes. Science, 335: 442-444, doi: 10.1126/science.1211694, Citation: "The groups on GO (for instance, hydroxyl, epoxy, etc.) tend to cluster and leave large, percolating regions of graphene sheets not oxidized."
Nguyen, M. T., Erni, R., & Passerone, D. (2012), Two-dimensional nucleation and growth mechanism explaining graphene oxide structures. Physical Review B, 86: 115406, doi: 10.1103/PhysRevB.86.115406, Citation: "In agreement with x-ray absorption data, transmission electron microscopy (TEM) has revealed that GO consists of disordered areas of high oxygen functionalization that surround patches of pristine graphene. In agreement with previously published micrographs, the TEM data of GO shown in this [Figure] reveals patches of pristine graphene that are surrounded by disordered areas of high oxygen functionalization."
Okotrub, A. V., Yudanov, N. F., Tur, V. A., Asanov, I. P., Shubin, Y. V., Vyalikh, D. V., & Bulusheva, L. G. (2012), Perforation of graphite in boiling mineral acid. physica status solidi (b), 249: 2620-2624, doi: 10.1002/pssb.201200143, Citation: "There are a number of works on the investigation of changes in the electronic state of graphene depending on the degree of oxidation and the size and chemical state of vacancies developed with the reduction of a graphite compound. Pacile et al. 2011 show the σ*-edge the spectrum of the initial GO shows three main peaks located at ~531.2, 533.3, and 535.0 eV, which could be assigned to the 1s->π*(C=0), 1s->π*(C-O-C), and 1s->σ*(O-H) transitions."
Perrozzi, F., Prezioso, S., Donarelli, M., Bisti, F., De Marco, P., Santucci, S., Nardone, M., Treossi, E., Palermo, V., & Ottaviano, L. (2012), Use of Optical Contrast To Estimate the Degree of Reduction of Graphene Oxide. Journal of Physical Chemistry C, 117: 620-625, doi: 10.1021/jp3069738, Citation: "Various theoretical models can be found in the literature on GO. All of them essentially suffer from oversimplification, as, once viewed in reality, GO exhibits a fascinating 'built-in' complexity. Transmission electron microscopy has is of great importance to study GO from atomically resolved images."
Pulido, A., Concepcion, P., Boronat, M., Botas, C., Alvarez, P., Menendez, R., & Corma, A. (2012), Reconstruction of the carbon sp2 network in graphene oxide by low-temperature reaction with CO. Journal of Materials Chemistry, 22: 51-56, doi: 10.1039/C1JM14514B, Citation: "The properties of graphite oxide are highly dependent on the synthetic route (process and conditions) and on the characteristics of the parent graphite, the resultant structure still being under debate."
Rhinow, D., Weber, N. E., & Turchanin, A. (2012), Atmospheric Pressure, Temperature-Induced Conversion of Organic Monolayers into Nanocrystalline Graphene. Journal of Physical Chemistry C, 116: 12295-12303, doi: 10.1021/jp301877p, Citation: "It has been recently demonstrated that GO sheets consist of nanocrystalline graphene areas along with disordered carbon networks. In contrast to annealed carbon nanomembranes (CNMs), orientational longrange order between nanocrystalline graphene areas was reported there. Annealed CNMs and GO sheets have similarities. Both of them are ultrathin materials and contain areas of nanocrystalline graphene along with areas of 2D amorphous carbon."
Su-xing, J., Ning-lin, Z., Dong, X., Yue, W., Yi-da, T., Chun-yan, L., Zhang, J., & Jian, S. (2012), Synthesis and anticoagulation activities of polymer/functional graphene oxide nanocomposites via Reverse Atom Transfer Radical Polymerization (RATRP). Colloids and Surfaces B: Biointerfaces, 101: 319-324, doi: 10.1016/j.colsurfb.2012.07.004, Citation: "."
Young, R. J., Kinloch, I. A., Gong, L., & Novoselov, K. S. (2012), The mechanics of graphene nanocomposites: A review. Composites Science and Technology, 72: 1459-1476, doi: 10.1016/j.compscitech.2012.05.005, Citation: "High-resolution TEM has also been used to study the structure of graphene oxide."
Zhong, J., Deng, J. J., Mao, B. H., Xie, T., Sun, X. H., Mou, Z. G., Hong, C. H., Yang, W., & Wang, S. D. (2012), Probing solid state N-doping in graphene by X-ray absorption near-edge structure spectroscopy. Carbon, 50: 335-338, doi: 10.1016/j.carbon.2011.08.046, Citation: "The electronic structures of pure graphene and GO have been widely investigated using XANES at the carbon (C) and oxygen (O) K-edges. For GO, three main features can be observed which are consistent with previous reports. The second feature at about 536 eV can be attributed to O-H groups."
Krueger, M., Berg, S., Stone, D. A., Strelcov, E., Dikin, D. A., Kim, J., Cote, L. J., Huang, J. H., & Kolmakov, A. (2011), Drop-Casted Self-Assembling Graphene Oxide Membranes for Scanning Electron Microscopy on Wet and Dense Gaseous Samples. ACS nano, 5: 10047-10054, doi: 10.1021/nn204287g, Citation: "Similar beam-induced distortions (shrinking) of GO membranes in vacuum were reported during TEM characterization upon exposure to electrons with doses on the order of 10^3 C/cm2."
Milowska, K., Birowska, M., & Majewski, J. A. (2011), Structural and Electronic Properties of Functionalized Graphene. Acta Phys. Pol. A, 120: 842-844, doi: PDF, Citation: "Remarkable electronic, mechanical and thermal properties of graphene have made it a promising candidate for a new generation of electronic devices."
Zhu, Q., Lu, Y. H., & Jiang, J. Z. (2011), Stability and Properties of Two-Dimensional Graphene Hydroxide. Journal of Physical Chemistry Letters, 2: 1310-1314, doi: 10.1021/jz200398d, Citation: "In experiment, the sp2-containing GOs are routinely observed. Even though the sp2 signals maybe come from an inhomogeneous phase composed of pure/hydroxidized graphene islands due to incomplete oxidation, these signals are still observed in high or completely oxidized GOs."
Pantelic, R. S., J. W. Suk, C. W. Magnuson, J. C. Meyer, P. Wachsmuth, U. A. Kaiser, R. S. Ruoff and H. Stahlberg (2011), Graphene: Substrate preparation and introduction. Journal of structural biology, 174: 234-238, doi: 10.1016/j.jsb.2010.10.002. Cited by (16)
Buckhout-White, S., Robinson, J. T., Bassim, N. D., Goldman, E. R., Medintz, I. L., & Ancona, M. G. (2013), TEM imaging of unstained DNA nanostructures using suspended graphene. Soft Matter, 9: 1414-1417, doi: 10.1039/C2SM26950C, Citation: "In a biological context, Pantelic et al. 2011 recently demonstrated a method for making graphene and hydrophilic graphene oxide TEM substrates, thereby facilitating the preparation of TEM samples from aqueous biomaterials."
Comolli, L. R., Siegerist, C. E., Shin, S. H., Bertozzi, C., Regan, W., Zettl, A., & De Yoreo, J. (2013), Conformational Transitions at an S-Layer Growing Boundary Resolved by Cryo-TEM. Angewandte Chemie International Edition, 52: 4829-4832, doi: 10.1002/anie.201300543, Citation: "The great potential of graphene for use as a support for biological cryo-TEM samples has recently been discussed."
Dyson, M. A., Sanchez, A. M., Patterson, J. P., O'Reilly, R. K., Sloan, J., & Wilson, N. R. (2013), A new approach to high resolution, high contrast electron microscopy of macromolecular block copolymer assemblies. Soft Matter, 9: 3741-3749, doi: 10.1039/C3SM27787A, Citation: "Pantelic et al. have also shown that due to their greater crystallinity and lower scattering cross-section graphene supports outperform even GO supports."
Longchamp, J. N., Escher, C., & Fink, H. W. (2013), Ultraclean freestanding graphene by platinum-metal catalysis. Journal of Vacuum Science & Technology B, 31: 020605-020605, doi: 10.1116/1.4793746 , Citation: "."
Sader, K., Stopps, M., Calder, L. J., & Rosenthal, P. B. (2013), Cryomicroscopy of Radiation Sensitive Specimens on Unmodified Graphene Sheets: Reduction of Electron-Optical Effects of Charging. Journal of structural biology, In Press, doi: 10.1016/j.jsb.2013.04.014, Citation: "Unmodified graphene has been tested as a support for positively stained biomolecules. Pantelic et al., 2011 described methods to transfer CVD monolayer graphene on Cu foil (Graphene Supermarket; CVD-Cu-2x2) to gold Quantifoil electron microscopy grids. The annealed grids on graphene were coated with a film of 0.5% w/w Formvar/ chloroform to add stability during Cu removal. [Figure] shows dissolution of the Cu foil by the flow of FeCl3 (Farnell AR413 37-46%), revealing grids with the graphene side up and attached to a Formvar film. The transfer of CVD monolayer graphene to Quantifoil grids yields a specimen support suitable for plunge freezing and imaging frozen-hydrated biological specimens by low dose methods"
Choudhuri, S. (2012), Bulk Synthesis of Graphene Nanosheets, PhD Dissertation National Institute of Technology Rourkela, doi: PDF, Citation: "Graphite oxide (GO) is a hydrophilic derivative of graphene. Surface bound oxidized functional groups contribute to the hydrophilic properties of graphene."
Hovden, R., & Muller, D. A. (2012), Efficient elastic imaging of single atoms on ultrathin supports in a scanning transmission electron microscope. Ultramicroscopy, 123: 59-65, doi: 10.1016/j.ultramic.2012.04.014, Citation: "The fabrication of clean, mono-atomic-layer membranes such as graphene and boron nitride has greatly simplified the imaging of individual light atoms in transmission electron microscopes (TEM)."
Kaiser, U. A. (2012), Low-Voltage TEM to explore physics and chemistry of low-dimensional and low-atomic number materials on the atomic scale, doi: PDF, Citation: "Graphene serves as substrate for biological structures."
Kaiser, U. A. (2012), Low-voltage TEM-current status and future prospects, EMC 2012, PDF, Citation: "Further, graphene can serve as a substrate for biological structures."
Longchamp, J. N., Latychevskaia, T., Escher, C., & Fink, H. W. (2012), Low-energy electron transmission imaging of clusters on free-standing graphene. Applied Physics Letters, 101: 113117, doi: 10.1063/1.4752717, Citation: "With the high-energy transmission electron microscope (TEM), graphene has already been successfully used as substrate for imaging objects such as stained DNA."
Pantelic, R. S., Meyer, J. C., Kaiser, U., & Stahlberg, H. (2012), The application of Graphene as a sample support in Transmission Electron Microscopy. Solid State Communications, 152: 1375-1382, doi: , Citation: "Crystalline supports demonstrate almost no phase contrast down to the resolution of their periodicity regardless of thickness. It is essentially electron transparent down to a resolution of 2.13 A, which is still outside resolutions routinely resolved in cryo-E. As expected, the background amplitude is comparable to that of images from vacuum areas. However, the direct transfer of CVD graphene from Cu foils to perforated amorphous carbon supports provided free standing areas of graphene and ample surrounding space with sufficient contrast for focusing a way from the region of interest — as is required by cryo-EM. The striking contrast of plasmid DNA across graphene without the necessity of metal shadowing could be demonstrated. Recent technical manuscripts have clearly demonstrated the benefits of graphene in the preparation of samples for cryo-EM — enhanced crystalline and electrical properties stand to drastically improve the stability and signal of weak - phase biological samples."
Ruoff, R. S. (2012), Personal perspectives on graphene: New graphene-related materials on the horizon. MRS bulletin, 37: 1314-1318, doi: 10.1557/mrs.2012.278, Citation: "Graphene and lightly oxidized graphene are superb supports for transmission electron microscopy imaging of biological molecules."
Sojoudi, H., Baltazar, J., Henderson, C., & Graham, S. (2012), Impact of post-growth thermal annealing and environmental exposure on the unintentional doping of CVD graphene films. Journal of Vacuum Science & Technology B, 30: 041213-041213, doi: 10.1116/1.4731472 , Citation: "."
Sousa, A. A., & Leapman, R. D. (2012), Development and Application of STEM for the Biological Sciences. Ultramicroscopy, 123: 38-49, doi: 10.1016/j.ultramic.2012.04.005, Citation: "The carbon film background intensity contributes a significant source of random noise to the mass measurements. Notably, this contribution of the background to measurement uncertainty could be greatly reduced by using novel one carbon atom-thick, atomically smooth sheets of graphene as specimen substrate."
Pantelic, R. S., Suk, J. W., Hao, Y., Ruoff, R. S., & Stahlberg, H. (2011), Oxidative Doping Renders Graphene Hydrophilic, Facilitating Its Use As a Support in Biological TEM. Nano letters, 11: 4319-4323, doi: 10.1021/nl202386p, Citation: "In subsequent work we described the transfer of continuous, single-layer graphene supports and compared the transmission properties of pristine graphene to graphene oxide and thin amorphous carbon in detail. CVD graphene was transferred to 1.2/1.3 μm Quantifoil TEM grids."
Rhinow, D., Weber, N. E., Turchanin, A., Golzhauser, A., & Kuhlbrandt, W. (2011), Single-walled carbon nanotubes and nanocrystalline graphene reduce beam-induced movements in high-resolution electron cryo-microscopy of ice-embedded biological samples. Applied Physics Letters, 99: 133701, doi: 10.1063/1.3645010, Citation: "New materials are increasingly used as TEM supports including graphene or graphene-like materials."
Westenfelder, B., J. C. Meyer, J. Biskupek, S. Kurasch, F. Scholz, C. E. Krill III, & U. A. Kaiser (2011), Transformations of Carbon Adsorbates on Graphene Substrates under Extreme Heat. Nano Lett., doi: 10.1021/nl203224z. Cited by (17)
Barreiro, A., Borrnert, F., Avdoshenko, S. M., Rellinghaus, B., Cuniberti, G., Rummeli, M. H., & Vandersypen, L. M. (2013), Understanding the catalyst-free transformation of amorphous carbon into graphene by current-induced annealing. Scientific reports, 3, doi: 10.1038/srep01115, Citation: "Recently, the non-catalytic graphitization of a-C into small (~10 nm) polycrystalline graphene by current-induced annealing of graphene has been reported. Temperatures as high as 2000°C have been estimated to be reached due to Joule heating."
Kaiser, U. A. (2013), Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope, Graphene 2013, doi: PDF, Citation: "Moreover we discuss structural changes under the influence of Joule heating and address the basic question how the amorphous phase of 2D objects is formed and can it can be described from direct images."
Meyer, J. (2013), New horizons and challenges in the microscopic characterization of 2-D materials, Graphene 2013, PDF, Citation: "The graphene substrate may further serve as an extreme thermal test platform, which then provides a means to study physisorbed carbon species under the influence of high temperatures and electron irradiation."
da Silva-Araújo, J., Nascimento, A. J. M., Chacham, H., & Nunes, R. W. (2013), Non-hexagonal-ring defects and structures induced by healing and strain in graphene and functionalized graphene. Nanotechnology, 24: 035708, doi: 10.1088/0957-4484/24/3/035708, Citation: "The experimental results show significant areas with holes, grain boundaries, isolated pentagon-heptagon pairs and clusters of carbon pentagons, hexagons, heptagons and a few octagons. Similar defect morphologies can be generated in exfoliated graphene by irradiation under extreme temperatures. We find that stress relaxation of a graphene sheet containing large initial concentrations of SW defects may lead to the formation of extended topological defects (ETDs), with morphological units that are very similar to those observed in the aforementioned experiments. We consider now more complex deformations of a graphene sheet, including small-sized holes generated by irradiation or by partially ripping a graphene sheet, coupled with strongly inhomogeneous bond deformations. These can be considered a model for severely strained and ripped graphene samples, such as those obtained by irradiation under extreme temperatures."
Barreiro, A., Borrnert, F., Rummeli, M. H., Buchner, B., & Vandersypen, L. M. (2012), Graphene at high bias: Cracking, layer by layer sublimation, and fusing. Nano letters, 12: 1873-1878, doi: 10.1021/nl204236u, Citation: "Recently, the non-catalytic graphitization of a-C into small (~10 nm) polycrystalline graphene has been reported. Temperatures as high as 2000°C have been estimated to be reached due to Joule heating."
Bonaccorso, F., Lombardo, A., Hasan, T., Sun, Z., Colombo, L., & Ferrari, A. C. (2012), Production and processing of graphene and 2d crystals. Materials Today, 15: 564-589, doi: 10.1016/S1369-7021(13)70014-2, Citation: "Westenfelder et al. 2011 used a current annealing process for the conversion. However, they did not report the resulting transport properties."
Borrnert, F., Barreiro, A., Wolf, D., Katsnelson, M. I., Buchner, B., Vandersypen, L. M., & Rummeli, M. H. (2012), Lattice expansion in seamless bilayer graphene constrictions at high bias. Nano letters, 12: 4455-4459, doi: 10.1021/nl301232t, Citation: "A temperature of 2000 K for the heat-induced evolution of hydrocarbons on graphene has been reported."
da Silva-Araújo, J., Nascimento, A. J. M., Chacham, H., & Nunes, R. W. (2012), Non-hexagonal-ring defects and structures induced by strain in graphene and in functionalized graphene. arXiv preprint, arXiv: 1203.3550, Citation: "Similar defect morphologies can be generated by irradiation under extreme temperatures. We find that stress relaxation of a graphene sheet containing large initial concentrations of SW defects may lead to the formation of ETDs, with morphological units that are very similar to those observed in the aforementioned experiments.We consider now more complex deformations of a graphene sheet, including small-sized holes generated by irradiation or by partially ripping a graphene sheet, coupled with strongly inhomogeneous bond deformations. These can be considered a model for severely strained and ripped graphene samples, such as those obtained by irradiation under extreme temperatures.
Fox, D., Verre, R., O'Dowd, B. J., Arora, S. K., Faulkner, C. C., Shvets, I. V., & Zhang, H. (2012), Investigation of coupled cobalt-silver nanoparticle system by plan view TEM. Progress in Natural Science: Materials International, 22: 186-192, doi: 10.1016/j.pnsc.2012.04.001, Citation: "As the development of semiconductor devices with ever smaller features, and the study of nanomaterials become more common, the need for high resolution imaging and analysis is more prevalent than ever."
Huang, P. Y., Meyer, J. C., & Muller, D. A. (2012), From atoms to grains: Transmission electron microscopy of graphene. MRS bulletin, 37: 1214-1221, doi: 10.1557/mrs.2012.183, Citation: "For example, graphene can be electrically contacted through the TEM sample holder, making it possible to pass high currents through graphene samples and heat them to extreme temperatures. These studies have achieved temperatures exceeding 2000 K in conjunction with HRTEM imaging, enabling the formation of nanocrystalline graphene from amorphous adsorbates."
Kaiser, U. A. (2012), Low-Voltage TEM to explore physics and chemistry of low-dimensional and low-atomic number materials on the atomic scale, Graphene 2012, PDF, Citation: "Further, graphene can now serve as an extreme thermal platform for physisorbed carbon species whose transformations can be imaged under the influence of Joule heat and electron irradiation atom-by atom."
Kaiser, U. A. (2012) Low-voltage TEM-current status and future prospects. EMC 2012, PDF, Citation: "Further, graphene can now serve as an extreme thermal platform for physisorbed carbon species whose transformations can be imaged under the influence of Joule heat and electron irradiation atom-by atom."
Kurasch, S., Kotakoski, J., Lehtinen, O., Skakalova, V., Smet, J., Krill III, C. E., Krasheninnikov, A. V., & Kaiser, U. (2012), Atom-by-atom observation of grain boundary migration in graphene. Nano letters, 12: 3168-3173, doi: 10.1021/nl301141g, Citation: "Interestingly, a flower defect structure can form from carbon adsorbates on graphene substrates at high temperatures."
Westenfelder, B. (2012) Combining High-Resolution TEM on Graphene With In-Situ Hall Measurements. Jahresbericht, doi: PDF, Citation: "HR images reveal graphene patches formed on top of the graphene membrane."
Westenfelder, B., Amende, T., Biskupek, J., Kurasch, S., Scholz, F., & Kaiser, U. (2012), In-situ HRTEM electrical experiments on graphene at high temperatures, EMC 2012, PDF, Citation: "We observed the transformation of physisorbed hydrocarbon adsorbates via amorphous carbon monolayers (at 1000K) into polycrystalline graphene (at 2000K)."
Zhu, W., Wang, H., & Yang, W. (2012), Evolution of graphene nanoribbons under low-voltage electron irradiation. Nanoscale, 4: 4555-4561, doi: 10.1039/C2NR30648D, Citation: "Atoms still prefer to be arranged in a zigzag sequence along the free edges at elevated temperatures, which is different from the early research."
Westenfelder, B. (2011), Heat-induced Transformations of Adsorbed Hydrocarbon Residues on Graphene, Jahresbericht, PDF, Citation: "In the case of gold nanoislands deposited on graphene, we were able to correlate a decrease in the particle surface area-to-volume ratio with an increase in temperature. The contrast at the edges is in agreement with the presence of carbon atoms; the slightly stronger contrast of the edge atoms compared to the lattice in [Figure] is a result of the contrast transfer function (CTF) of the microscope at the present conditions. In a statistical analysis of the edge configurations, 58 % of all visible edges could be assigned clearly to one of the geometries. Among the classified edges, a dominant fraction — 83 % — exhibits the armchair conformation, 14 % manifest the 5-7 % reconstructed zigzag edge structure, and only 3 % are found in the unreconstructed zigzag geometry."
Westenfelder, B., J. C. Meyer, J. Biskupek, G. Algara-Siller, L. G. Lechner, J. Kusterer, U. A. Kaiser, C. E. Krill, E. Kohn, F. Scholz (2011), Graphene-based sample supports for in situ high-resolution TEM electrical investigations. J. Phys. D: Appl. Phys., 44: 055502, doi: 10.1088/0022-3727/44/5/055502. Cited by (12)
Petkov, N. (2013), In Situ Real-Time TEM Reveals Growth, Transformation and Function in One-Dimensional Nanoscale Materials: From a Nanotechnology Perspective. ISRN Nanotechnology, 2013, 21 pages, doi: 10.1155/2013/893060, Citation: "The first approach uses prefabricated circuitry developed by lithography on silicon chips containing thin silicon nitride membranes [Figure]."
Sola, F., Niu, J., & Xia, Z. H. (2013), Heating induced microstructural changes in graphene/Cu nanocomposites. Journal of Physics D, 46: 065309, doi: 10.1088/0022-3727/46/6/065309, Citation: "Recently, the stability of Au and Pt nanoparticles on graphene at high temperatures was demonstrated using in situ transmission electron microscopy (TEM)."
Huang, P. Y., Meyer, J. C., & Muller, D. A. (2012), From atoms to grains: Transmission electron microscopy of graphene. MRS bulletin, 37: 1214-1221, doi: 10.1557/mrs.2012.183, Citation: "For example, graphene can be electrically contacted through the TEM sample holder, making it possible to pass high currents through graphene samples and heat them to extreme temperatures."
Pantelic, R. S., Meyer, J. C., Kaiser, U., & Stahlberg, H. (2012), The application of Graphene as a sample support in Transmission Electron Microscopy. Solid State Communications, 152, doi: 10.1016/j.ssc.2012.04.038, Citation: "One way to remove this contamination is to heat the graphene membrane in the vacuum prior to beam exposure. By passing electrical current, graphene TEM supports may also serve as an in-situ heating platform. Joule heating of the graphene membrane can reach temperatures in excess of 2000 K. Westenfelder et al. succeeded in removing the gold particles after heating, thereby isolating the carbon shells [Figure]."
Panthani, M. G., Hessel, C. M., Reid, D., Casillas, G., Jose-Yacaman, M., & Korgel, B. A. (2012), Graphene-Supported High-Resolution TEM and STEM Imaging of Silicon Nanocrystals and their Capping Ligands. Journal of Physical Chemistry C, 116: 22463-22468, doi: 10.1021/jp308545q, Citation: "It has excellent mechanical, thermal, and electrical stability and conducts heat and electricity, so it can dissipate electrostatic charging and sample heating under the electron beam during imaging."
Westenfelder, B. (2012) Combining High-Resolution TEM on Graphene With In-Situ Hall Measurements. Jahresbericht, doi: PDF, Citation: "The current annealing procedure has the advantage of achieving temperatures until the regime of 2000 K."
Westenfelder, B., Amende, T., Biskupek, J., Kurasch, S., Scholz, F., & Kaiser, U. (2012), In-situ HRTEM electrical experiments on graphene at high temperatures, EMC 2012, PDF, Citation: "Recently, we have realized an approach to study free-standing graphene and its adsorbates at high temperatures (300 K - 2000 K) in a transmission electron microscope (TEM) with atomic resolution. We showed the effect of in-situ Joule heating on graphene membranes in HRTEM images at temperatures until 2000 K."
Lee, G. D. (2011), The formation and stability of topological defects in graphene. Atomic structure of nanosystems from transmission electron, Nanocarbon Meeting, PDF, Citation: "A specially designed TEM sample carrier platform enables reaching local temperatures in excess of 2000 K."
Pantelic, R. S., Suk, J. W., Hao, Y., Ruoff, R. S., & Stahlberg, H. (2011), Oxidative Doping Renders Graphene Hydrophilic, Facilitating Its Use As a Support in Biological TEM. Nano letters, 11: 4319-4323, doi: 10.1021/nl202386p, Citation: "Graphene has renewed interest in crystalline TEM supports."
Westenfelder, B. (2011), Heat-induced Transformations of Adsorbed Hydrocarbon Residues on Graphene, Jahresbericht, PDF, Citation: "As reference points for the local temperature, we used the melting of gold particles (diameter dependent), the transition from amorphous to crystalline silicon nitride and the evaporation of SiN (amorphous SiN is known to crystallize at 1600 K and to begin decomposing around 2000 K). The experimental concept and thermal calibration have been described in great detail. Moreover, observations made during mild heating conditions help in the estimation of the temperature for our sample geometry. Above a certain temperature, the first particles form liquid drops and begin to evaporate."
Westenfelder, B., Meyer, J. C., Biskupek, J., Kurasch, S., Scholz, F., Krill III, C. E., & Kaiser, U. (2011), Transformations of carbon adsorbates on graphene substrates under extreme heat. Nano letters, 11: 5123-5127, doi: 10.1021/nl203224z, Citation: "As reference points for the local temperature, we used the melting of gold particles (diameter dependent), the transition from amorphous to crystalline silicon nitrided (1600 K), and the evaporation of SiN (2000 K). Observations made during mild heating conditions help in the estimation of the temperature distribution for our sample geometry. Above a certain temperature, the first particles form liquid drops and begin to evaporate (see video M1 in the Supporting Information)."
Westenfelder, B. (2010), Heat Induced Dynamics of Gold Nanoparticles on Atomically Clean Graphene, Jahresbericht, PDF, Citation: "For the in-situ Joule heating of a freely suspended sheet of graphene, we employ a microfabricated, in-situ applicable TEM sample carrier that was developed recently. A graphene flake together with predeposited gold nanoparticles has been positioned directly above the electrode fingers of that carrier [Figure]. Its special design allows to obtain reliably temperatures in excess of 1000 K in atomically thin, crystalline and electron transparent single- and few-layer graphene membranes. Moreover, in case of our deposited gold nanoislands, we could nicely confirm the decrease of the particle surface-area-to-volume ratio, i.e. a transformation to more spherical shapes, with increasing temperature. After exceeding a certain temperature limit, the first of the almost spherically shaped particles form liquid drops and start to evaporate [Figure]."
2010
Chuvilin, A., A. N. Khlobystov, D. Obergfell, M. Haluska, S. Yang, S. Roth, & U. A. Kaiser (2010), Observations of Chemical Reactions at the Atomic Scale: Dynamics of Metal-Mediated Fullerene Coalescence and Nanotube Rupture. Angew. Chem. Int. Ed. , 49: 193, doi: 10.1002/anie.200902243. Cited by (23)
Popov, A. A., Yang, S., & Dunsch, L. (2013), Endohedral Fullerenes. Chemical reviews, In Press, doi: 10.1021/cr300297r, Citation: "The dynamics of Dy atoms in Dy@C82@SWNT peapods was studied by Chuvilin et al. using aberration-corrected (AC) HRTEM with the 80 kV electron beam. The breaking of C82 cages and their coalescence leading to the formation of the inner nanotube encapsulating Dy clusters was initiated by motions of Dy atoms inside Dy@C82. The details of this process on a second time scale were observed by HRTEM. The mechanism involving the ionization of endohedral Dy3+ by incident electrons with formation of very reactive Dy4+ responsible for the cage breaking was proposed."
Biskupek, J., P. Hartel, M. Haider, U. A. Kaiser (2012), Effects of residual aberrations explored on single-walled carbon nanotubes. Ultramicroscopy, 116: 1-7, doi: 10.1016/j.ultramic.2012.03.008, Citation: "In order to study SWNTs and graphene at or close to it’s atomic scale a reduction of dE*CC is mandatory by means of special settings of the electron gun, using a monochromator or a CC-corrector. Good results were shown in recent publications."
Karousis, N., Sato, Y., Suenaga, K., & Tagmatarchis, N. (2012), Direct evidence for covalent functionalization of carbon nanohorns by high-resolution electron microscopy imaging of C< sub> 60 conjugated onto their skeleton. Carbon, 50: 3909-3914, doi: 10.1016/j.carbon.2012.04.035, Citation: "Actually, when carbon nanotubes used as specimen support or as host material for encapsulation, fullerene spheres have been imaged and identified with TEM."
Pantelic, R. S., Meyer, J. C., Kaiser, U., & Stahlberg, H. (2012), The application of Graphene as a sample support in Transmission Electron Microscopy. Solid State Communications, 152: 1375-1382, doi: 10.1016/j.ssc.2012.04.038, Citation: "Chemical reactions can now be studied inside carbon nanotubes (CNT’s)."
Allen, C. S., Ito, Y., Robertson, A. W., Shinohara, H., & Warner, J. H. (2011), Two-dimensional coalescence dynamics of encapsulated metallofullerenes in carbon nanotubes. ACS nano, 5: 10084-10089, doi: 10.1021/nn204003h, Citation: "Coalescence dynamics of 1D packed fullerenes in nanotubes has been extensively examined using 80 kV electron beam irradiation. It has been shown that metallofullerenes fuse together to form an inner carbon nanotube, with the metal atoms. In some cases the metal atoms react with the host tube, leading to destruction."
Chamberlain, T. W., Champness, N. R., Schroder, M., & Khlobystov, A. N. (2011), A Piggyback Ride for Transition Metals: Encapsulation of Exohedral Metallofullerenes in Carbon Nanotubes. Chemistry-A European Journal, 17: 668-674, doi: 10.1002/chem.201001288, Citation: "The fullerene-nanotube interaction energy has been measured to be ~3.0 eV (288 kJ/mol) for C60 and a single-walled carbon nanotube (SWNT), and can be higher for larger fullerene cages. Previously, we have exploited the unique affinity of nanotubes to absorb fullerenes with metals inside leading to (M@Cn)@SWNT structures in an exceptionally high yield (up to 100%), in which metal atoms are arranged in a perfect chain along the nanotube channel [Figure]. Although it has been demonstrated that once endohedral fullerenes are inside the nanotube, it is possible to break the fullerene cages by using radiation, thereby liberating the metal atoms into the nanotube cavity, these are often high energy processes and difficult to control. The chemical reactivity of metal atoms in endohedral fullerenes, such as M@C82, is passivated by the fullerene shell enveloping that metal, so that the metal atom has to break through the shell in order to be involved in any chemical reactions within the nanotube."
Chamberlain, T. W., Meyer, J. C., Biskupek, J., Leschner, J., Santana, A., Besley, N. A., Bichoutskaia, E., Kaiser, U., & Khlobystov, A. N. (2011), Reactions of the inner surface of carbon nanotubes and nanoprotrusion processes imaged at the atomic scale. Nature Chemistry, 3: 732-737, doi: 10.1038/nchem.1115, Citation: "On coalescence of the carbon cages, the metal atoms move randomly within the SWNT or form small clusters at lower energies of the e-beam (80 keV)."
del CarmenaGimenez-Lopez, M. (2011), Functionalised endohedral fullerenes in single-walled carbon nanotubes. Chemical Communications, 47: 2116-2118, doi: 10.1039/C0CC02929G, Citation: "In our study, we perform AC-HRTEM at 80 kV which, combined with the 'carbon nano test-tube approach', makes it possible to image molecules with increasingly more complex structures."
Gao, J., Blondeau, P., Salice, P., Menna, E., Bartova, B., Hebert, C., Lechner, J., Kaiser, U., Milko, M., Ambrosch-Draxl, C., & Loi, M. A. (2011), Electronic Interactions between "Pea" and "Pod": The Case of Oligothiophenes Encapsulated in Carbon Nanotubes. small, 7: 1807-1815, doi: 10.1002/smll.201100319, Citation: "In the past decade, many materials, including metallofullerenes, metallocenes, organometallic molecules, and nanocrystals, have been successfully confined in the nanosized inner cavity of carbon nanotubes."
Kaiser, U. (2011), Imaging and Spectroscopy of Carbon Nanostructures with 80 and 20 keV Electrons. Microscopy and Microanalysis, 17: 1488-1489, doi: 10.1017/S1431927611008312, Citation: "At 80 keV, AC-HRTEM provides structural information on both, the exterior (functional groups) and/or the interior of individual fullerenes and metallofullerenes at the near-atomic level in direct space and real time."
Kaiser, U., Biskupek, J., Meyer, J. C., Leschner, J., Lechner, L., Rose, H., Stoger-Pollach, M., Khlobystov, A. N., Hartel, P., Muller, H., Haider, M., Eyhusen, S., & Benner, G. (2011), Transmission electron microscopy at 20 kV for imaging and spectroscopy. Ultramicroscopy, 111: 1239-1246, doi: 10.1016/j.ultramic.2011.03.012, Citation: "Defect-free carbon nanotubes are e-beam transparent and structurally stable for infinite time at or below 80 kV."
Khlobystov, A. N. (2011), Carbon nanotubes: from nano test tube to nano-reactor. ACS nano, 5: 9306-9312, doi: , Citation: "The thicker, and hence more conducting, walls of the nanotube as well as close contact between the guest molecules and the inner surface of nanotube were shown to enhance the stability of encapsulated molecules under the e-beam. It should be noted, however, that the nanotube interior is not as inert toward metal catalysts as was initially believed. HRTEM observations clearly show that small clusters of Dy can catalyze a rupture of the nanotube container."
Lee, G. D. (2011), The formation and stability of topological defects in graphene. Atomic structure of nanosystems from transmission electron, Nanocarbon Meeting, PDF, Citation: "In this talk, we provide an overview and discuss examples of transformation routes starting from (a) functionalized endohedral fullerenes inside SWNTs."
Ran, K., Zuo, J. M., Chen, Q., & Shi, Z. (2011), Electron beam stimulated molecular motions. ACS nano, 5: 3367-3372, doi: 10.1021/nn2006909, Citation: "For example, several kinds of chemical reactions have been reported in peapods."
Warner, J. H., Plant, S. R., Young, N. P., Porfyrakis, K., Kirkland, A. I., & Briggs, G. A. D. (2011), Atomic Scale Growth Dynamics of Nanocrystals within Carbon Nanotubes. ACS nano, 5: 1410-1417, doi: 10.1021/nn1031802, Citation: "In several cases, structural transformations have been captured in real time. When peapods (fullerenes inside nanotubes) are irradiated with an 80 kV electron beam, the fullerenes coalesce and eventually form a high-quality, smaller diameter nanotube within the original host nanotube. If metallofullerenes are used, the metal atoms are confined to the inner region of the newly formed nanotube. The presence of metal atoms within the carbon structure can also influence these structural transformations. Studies into the rupturing of endohedral fullerene cages and the subsequent release of metal atoms have been previously performed. Experiments with Dy@C82 peapods have also been reported (at 80 kV), but the Dy atoms ruptured the nanotube host and only disordered clusters were observed. This was attributed to the presence of Dy4+ and its inability to form a carbide phase to stabilize the structure. The fact that a nanocrystalline carbide phase is formed is not surprising and is most likely the reason behind the stability of the cluster as compared to the case of Dy atoms. The previous report of Dy atoms showed that stable clusters are not formed, and instead, destruction of the nanotube host occurred. A key component in our experiments was that we were able to observe the dynamics of nanocrystal formation due to the high concentration of metal atoms within the nanotube. The Pr2@C72 has two metal atoms in each cage compared to La@C82 and Dy@C82."
Warner, J. H., Young, N. P., Kirkland, A. I., & Briggs, G. A. D. (2011), Resolving strain in carbon nanotubes at the atomic level. Nature materials, 10: 958-962, doi: 10.1038/nmat3125, Citation: "The incorporation of aberration correctors into transmission electron microscopes has opened up a new field in performing atomic-resolution microscopy at low accelerating voltages. This has been revolutionary for carbon nanomaterials, where a low accelerating voltage of 80 kV is needed to reduce knock-on damage to sp2 carbon nanomaterials such as fullerenes and peapods."
Yumura, T. (2011), Chemically reactive species remain alive inside carbon nanotubes: a density functional theory study. Physical Chemistry Chemical Physics, 13: 337-346, doi: 10.1039/C0CP00796J, Citation: "Inside a carbon nanotube host, transformation of a guest molecule and its resultant reaction with an adjacent guest have been reported to occur by heating or electron irradiation. During the reactions, a reactive guest species should be formed as a reaction intermediate. The inner reactive species only seem to attack adjacent guests to result in guest polymerization. These findings can help us to understand unusual chemical reactions proceeding easily inside a tube."
Friedrich, H., Frederik, P. M., & Sommerdijk, N. A. (2010), Imaging of Self-Assembled Structures: Interpretation of TEM and Cryo-TEM Images. Angewandte Chemie International Edition, 49: 7850-7858, doi: 10.1002/anie.201001493, Citation: "A recent beautiful example illustrates how far TEM has developed over the past few years: aberration-corrected TEM with an acceleration voltage of only 80 kV provided atomic images of metal-mediated fullerene coalescence and nanotube rupture [Figure]."
Krishna, V., Stevens, N., Koopman, B., & Moudgil, B. (2010), Optical heating and rapid transformation of functionalized fullerenes. Nature nanotechnology, 5: 330-334, doi: , Citation: "Experimental evidence indicate that the activation energy for the coalescence of pristine fullerenes is reduced in the presence of other atoms."
Leschner, J., Biskupek, J., Chuvilin, A., & Kaiser, U. (2010), Accessing the local three-dimensional structure of carbon materials sensitive to an electron beam. Carbon, 48: 4042-4048, doi: 10.1016/j.carbon.2010.07.009, Citation: "The nature of the carbon allotropes diamond, graphite, nanotubes and fullerenes has been investigated by recently by aberration corrected HRTEM imaging with sub-Angstrom resolution."
Mercado, B. Q., Stuart, M. A., Mackey, M. A., Pickens, J. E., Confait, B. S., Stevenson, S., Easterling, M., L., Valencia, R., Rodriguez-Fortea, A., Poblet, J. M., Olmstead, M., M., & Balch, A. L. (2010), Sc2 (μ2-O) Trapped in a Fullerene Cage: The Isolation and Structural Characterization of Sc2 (μ2-O)@ C s (6)-C82 and the Relevance of the Thermal and Entropic Effects in Fullerene Isomer Selection. Journal of the American Chemical Society, 132: 12098-12105, doi: 10.1021/ja104902e, Citation: "In addition to the mechanical trapping of these cages within the nanotube walls, reactions between fullerenes, such as their fusion, have been observed."
Nicholls, R. J., Sader, K., Warner, J. H., Plant, S. R., Porfyrakis, K., Nellist, P. D., Briggs, G. A. D., & Cockayne, D. J. (2010), Direct Imaging and Chemical Identification of the Encapsulated Metal Atoms in Bimetallic Endofullerene Peapods. ACS nano, 4: 3943-3948, doi: 10.1021/nn100823e, Citation: "Techniques that can provide atomic resolution information are therefore crucial characterization tools for these materials. High-resolution transmission electron microscopy (HRTEM) is such a technique and has often been used for the characterization of peapods."
Warner, J. H., Rummeli, M. H., Bachmatiuk, A., & Buchner, B. (2010), Structural transformations of carbon chains inside nanotubes. Physical Review B, 81: 155419, doi: 10.1103/PhysRevB.81.155419, Citation: "."
Chuvilin, A., U. A. Kaiser, E. Bichoutskaia, N. A. Besley, A. N. Khlobystov (2010), Direct transformation of graphene to fullerene. Nature Chemistry, 2: 450-453, doi: 10.1038/nchem.644. Cited by (65)
Calvaresi, M., Quintana, M., Rudolf, P., Zerbetto, F., & Prato, M. (2013), Rolling up a Graphene Sheet. ChemPhysChem, Early View, doi: 10.1002/cphc.201300337, Citation: "Recently, aberration-corrected transmission electron microscopy allowed the direct visualization, in real time, of the process of fullerene formation from a graphene sheet. Four critical steps of this top-down mechanism were identified: 1) loss of carbon atoms at the edges of graphene, leading to 2) the formation of pentagons, which 3) triggers the curving of graphene into a bowl-shaped structure, and 4) subsequently zips up its open edges to form a closed fullerene structure."
Chang, J. Y., Wu, J. S., & Chang, C. R. (2013), Exact Hamiltonians with Rashba and cubic Dresselhaus spin-orbit couplings on a curved surface. Physical Review B, 87: 174413, doi: 10.1103/PhysRevB.87.174413, Citation: "."
Cocchi, C., Prezzi, D., Ruini, A., Caldas, M. J., Fasolino, A., & Molinari, E. (2013), Concavity Effects on the Optical Properties of Aromatic Hydrocarbons. Journal of Physical Chemistry C, doi: , Citation: "In that work, the formation of C60 from a graphene sheet is visualized in real time through a transmission electron microscope. The process is modeled in four steps: the initial edge etching of a graphene flake with over 80 C atoms is followed by the formation of pentagons and then by the curving of the graphene into a bowl-shape structure. Finally, the open edges are zipped up to form a closed fullerene structure."
Delgado, J. L., Filippone, S., Giacalone, F., Herranz, M. a., Illescas, B., Perez, E. M., & Martín, N. (2013), Buckyballs, Topics in Current Chemistry, doi: 10.1007/128_2012_414, Citation: "It is interesting to note that in situ TEM experiments correlated with quantum chemical modeling have demonstrated that flat graphene sheets undergo a direct transformation to fullerene cages under 80-keV electron beam irradiation."
Kaiser, U. A. (2013), Properties of graphene and other low-dimensional objects obtained from imaging and spectroscopy experiments in a transmission electron microscope, Graphene 2013, doi: PDF, Citation: "We discuss then electron-beam-induced transformation route of different nano-carbon structures."
Mojica, M., Alonso, J. A., & Mendez, F. (2013), Synthesis of fullerenes. Journal of Physical Organic Chemistry, 26: 526-539, doi: 10.1002/poc.3121, Citation: "Chuvilin et al. proposed the formation of C60 from graphene under transmission electron microscopy (TEM) conditions. They studied graphene sheets by TEM and observed that while exposed to an electron beam of 80 keV, the edges of the graphene sheets change continuously, leading to the formation of C60. The high energy of the electron beam is transferred to the carbon atoms, producing the fragmentation of the graphene sheets in flake-like structures that finally produce fullerene molecules."
Qian, K., Zhou, L., Liu, J., Yang, J., Xu, H., Yu, M., Nouwens, A., Zou, J., Monteiro, M. J., & Yu, C. (2013), Laser Engineered Graphene Paper for Mass Spectrometry Imaging. Scientific Reports, 3: 1415, doi: 10.1038/srep01415, Citation: "The in situ formation of C60 on the surface of graphene under 80 keV electron beam irradiation was observed by Chuvilin et al. Carbon clusters produced from graphene during irradiation may have lower atomic energy (~-0.26 eV/atom) and thus are more stable compared to graphene. It was reported that graphene was not stable under electron beam at an acceleration voltage of 80 kV."
Santana, A., Zobelli, A., Kotakoski, J., Chuvilin, A., & Bichoutskaia, E. (2013), Inclusion of radiation damage dynamics in high-resolution transmission electron microscopy image simulations: The example of graphene. Physical Review B, 87: 094110, doi: 10.1103/PhysRevB.87.094110, Citation: "Many practically useful materials have been studied using HRTEM with great emphasis on carbon nanostructures. Transformation of a finite graphene flake into a fullerene cage under the 80 keV e-beam has recently been observed in experiment. In small fragments of graphene a loss of even one carbon atom at the edge can enable a sequence of thermodynamically driven transformations which trigger the curving of the fragment and its subsequent closure into a fullerene molecule. Static ab initio calculations of the initial steps of the flake-to-fullerene evolution have demonstrated a viable route for a 'top-down' mechanism of fullerene formation in HRTEM. [Figure] shows the time evolution of the structures assuming an electron flux rate to be j = 4.1*106 electron/(s nm2) as estimated directly from experimental images. Flakes containing about 300 atoms typically get closed into cages ranging in size between C140 and C160; these larger cages have also been found in HRTEM."
Skowron, S. T., Lebedeva, I. V., Popov, A. M., & Bichoutskaia, E. (2013), Approaches to modelling irradiation-induced processes in transmission electron microscopy. Nanoscale, Advance Article, doi: 10.1039/C3NR02130K, Citation: "The creation of irradiation-induced defects in a nanostructure can lead to a considerable realignment of bonds, such that a transformation into an entirely new species takes place. One of the most striking examples of such a transformation is the formation of a fullerene from an initially flat graphene flake."
Wang, M., Yan, C., Ma, L., Hu, N., & Zhang, G. (2013), Numerical analysis of shape transition in graphene nanoribbons. Computational Materials Science, 75: 69-72, doi: 10.1016/j.commatsci.2013.04.014, Citation: "Recent quantum chemical modelling demonstrated that the formation of pentagon rings at edges is one of four critical steps in fullerene formation."
Arayachukeat, S., Palaga, T., & Wanichwecharungruang, S. P. (2012), Clusters of Carbon Nanospheres Derived from Graphene Oxide. ACS applied materials & interfaces, 4: 6808-6815, doi: 10.1021/am3019959, Citation: "Transformation of one carbon nanostructure into other by both gas and solution phase processes have also been reported, including, for example, the transformation of graphene sheets into fullerenes. At present, there is no solid explanation as to how the 5 nm spheres are formed. One plausible explanation is that the giant fullerene could directly be generated from GOShs during the sonication process. This explanation is based on the report of Chuvilin et al. who demonstrated that fullerenes could be produced directly from graphene sheets through the reaction of carbons at the edge of carbon network sheets."
Berne, O., & Tielens, A. G. (2012), Formation of buckminsterfullerene (C60) in interstellar space. Proceedings of the National Academy of Sciences, 109: 401-406, doi: 10.1073/pnas.1114207108, Citation: "We envision that this is followed by migration of the pentagons within the molecule, leading to the zipping-up of the open edges forming the closed fullerene [Figure]"
Bittencourt, C., & Van Tendeloo, G. (2012), Carbon Nanoforms. Handbook of Nanoscopy, 1&2: 995-1070, doi: 10.1002/9783527641864.ch28, Citation: "The demonstration of the remarkable transport properties of graphene in 2004 by Geim and Novoselov triggered intense interest in its electronic structure."
Bittencourt, C., Hitchock, A. P., Ke, X., Van Tendeloo, G., Ewels, C. P., & Guttmann, P. (2012), X-ray absorption spectroscopy by full-field X-ray microscopy of a thin graphite flake: Imaging and electronic structure via the carbon K-edge. Beilstein Journal of Nanotechnology, 3: 345-350, doi: 10.3762/bjnano.3.39, Citation: "The demonstration of the remarkable transport properties of graphene in 2004 by Geim and Novoselov triggered intense interest in its electronic structure."
Bosch-Navarro, C., Coronado, E., Martí-Gastaldo, C., Sanchez-Royo, J. F., & Gomez, M. G. (2012), Influence of the pH on the synthesis of reduced graphene oxide under hydrothermal conditions. Nanoscale, 4: 3977-3982, doi: 10.1039/C2NR30605K, Citation: "It has been extensively described that 2D systems are difficult to synthesize as they tend to scroll up giving quasi-0D onions or 1D tubes in order to decrease the peripheral dangling bonds, thus decreasing the total energy of the system."
Cheng, Y. C., Wang, H. T., Zhu, Z. Y., Zhu, Y. H., Han, Y., Zhang, X. X., & Schwingenschlogl, U. (2012), Strain-activated edge reconstruction of graphene nanoribbons. Physical Review B, 85: 073406, doi: 10.1103/PhysRevB.85.073406, Citation: "."
Dunk, P. W., Kaiser, N. K., Hendrickson, C. L., Quinn, J. P., Ewels, C. P., Nakanishi, Y., Sasaki, Y., Shinohara, H., Marshall, A. G., & Kroto, H. W. (2012), Closed network growth of fullerenes. Nature Communications, 3: 855, doi: 10.1038/ncomms1853
Dunk, P. W., Kaiser, N. K., Mulet-Gas, M., Rodríguez-Fortea, A., Poblet, J. M., Shinohara, H., Hendrickson, C. L., Marshall, A. G., & Kroto, H. W. (2012), The Smallest Stable Fullerene, M@ C28 (M= Ti, Zr, U): Stabilization and Growth from Carbon Vapor. Journal of the American Chemical Society, 134: 9380-9389, doi: 10.1021/ja302398h, Citation: It has been demonstrated that U@C28 forms directly from carbon vapor and not due to fragmentation of larger fullerenes, i. e. one initial formation mechanisms for U@C28 is the top-down formation, in which a graphite fragment originating from the target is directly involved."
Feng, J., Li, W., Qian, X., Qi, J., Qi, L., & Li, J. (2012), Patterning of graphene. Nanoscale, 4: 4883-4899, doi: 10.1039/C2NR30790A, Citation: "Recently Chuvilin et al. observed that the graphene flake stripped from a single-layer graphene edge by electron beam irradiation could automatically transform into fullerene C60 molecule, which is quite different from the fullerene formation mechanism based on carbon-cluster coalescence."
Huang, P. Y., Meyer, J. C., & Muller, D. A. (2012), From atoms to grains: Transmission electron microscopy of graphene. MRS bulletin, 37: 1214-1221, doi: 10.1557/mrs.2012.183, Citation: "Finally, graphene can be turned into fullerenes and vice versa."
Irle, S., Page, A. J., Saha, B., Wang, Y., Chandrakumar, K. R. S., Nishimoto, Y., Qian, H. J., & Morokuma, K. (2012), Atomistic mechanism of carbon nanostructure self-assembly as predicted by nonequilibrium QM/MD simulations. In Practical Aspects of Computational Chemistry II: 103-172, doi: 10.1007/978-94-007-0923-2_5, Citation: "."
Kaiser, U. A. (2012), Low-Voltage TEM to explore physics and chemistry of low-dimensional and low-atomic number materials on the atomic scale, Graphene 2012, PDF, Citation: "We take advantage of the dynamics of atom knock-on processes under the electron beam to understand fundamental new transformation routes between carbon nanostructures atom-by-atom ."
Kaiser, U. A. (2012), Low-voltage TEM-current status and future prospects. EMC 2012, PDF, Citation: "We use graphene and carbon nanotubes as substrates for radiation-sensitive compounds and take advantage of the dynamics of atom knock-on processes under the electron beam to understand fundamental new transformation routes between carbon nanostructures atom-by-atom."
Kinyanjui, M. K., Kramberger, C., Pichler, T., Meyer, J. C., Wachsmuth, P., Benner, G., & Kaiser, U. (2012), Direct probe of linearly dispersing 2D interband plasmons in a free-standing graphene monolayer. EPL (Europhysics Letters), 97: 57005, doi: 10.1209/0295-5075/97/57005, Citation: "Graphene is considered to be the basic structural unit of several forms of carbon including fullerenes, single-wall carbon nanotubes (SWCNT) and graphite."
Kong, X., Huang, Y., & Chen, Y. (2012), Difference in formation of carbon cluster cations by laser ablation of graphene and graphene oxide. Journal of Mass Spectrometry, 47: 523-528, doi: 10.1002/jms.2985, Citation: "Since it has been prepared by Novoselov et al., graphene (G) has emerged to become the most exciting two-dimensional material with many unique characteristics. Recently, Chuvilin et al. have observed a different process of fullerene formation from a sheet of G in real time by the method of aberration-corrected transmission electron microscopy. In their wonderful jobs, Chuvilin et al. have observed the process of fullerene formation from a G sheet in real time. With the aid of quantum chemical modeling, they explained the process as a top-down mechanism for fullerene formation by four steps: (1) the loss of carbon atoms at the edge of G because of the high-energy e-beam, (2) the formation of pentagons, (3) subsequent curving of the flake to form a bowl-shaped structure and (4) closing the open edges to form a fullerene cage. We think this top-down mechanism can be also applied here to explain our results. The main difference is that the 80-keV electron beam was replaced by the laser pulses at 355nm in this experiment. Although there is no direct proof such as the experimental transmission electron microscopy images, several results observed in our experiments do support the suggestion: (1) the observed cluster distribution in [Figure] (a) are much narrower than those observed in (b) or (c), which is consistent with Chuvilin’s results. Besides, all steps of (2), (3) and (4) suggested by Chuvilin are thermodynamically favorable. Because there will be a significant energetic penalty in the curving step due to the noncovalent interactions between the underlying G sheet and the flake, the size of the etched G will be limited within the range to enable the thermodynamically driven steps for the formation of fullerene. A top-down mechanism including both direct transformation of G to fullerene verified by Chuvilin et al. previously and fragmentation of large-sized fullerenes is suggested for the process of laser ablation of G."
Laszlo, I., & Zsoldos, I. (2012), Graphene-based molecular dynamics nanolithography of fullerenes, nanotubes and other carbon structures. EPL, 99: 63001, doi: 10.1209/0295-5075/99/63001, Citation: "Increasing and decreasing the environmental temperatures corresponds to the random interaction with an environmental particle or it corresponds to an appropriate electron beam. Chuvilin et al. in their transmission electron microscopy experiment demonstrated that a direct transformation of flat graphene sheets to fullerene cages is possible. In the rational chemical synthesis of C60 the authors presented the synthetic route to the C60H30 polycyclic aromatic hydrocarbon (PAH)."
Laszlo, I., & Zsoldos, I. (2012), Molecular dynamics simulation of carbon nanostructures: The D< sub> 5h C< sub> 70 fullerene. Physica E: Low-dimensional Systems and Nanostructures, In Press, doi: 10.1016/j.physe.2012.08.009, Citation: "Chuvilin et al. in their transmission electron microscopy experiment demonstrated that a direct transformation of flat graphene sheets to fullerenee cages is possible."
Lebedeva, I. V., Knizhnik, A. A., Popov, A. M., & Potapkin, B. V. (2012), Ni-assisted transformation of graphene flakes to fullerenes. Journal of Physical Chemistry C, 116: 6572-6584, doi: 10.10 21/jp212165g, Citation: "New ways to produce fullerenes which allow controlling their structure during the synthesis were realized recently. The transformation of a small graphene flake to a fullerene under the action of an electron beam in the transmission electron microscope was demonstrated. The following mechanism of the transformation was proposed. First, etching of the graphene flake by the electron beam leads to formation of a notch in the flake. Then the flake relaxes with zipping the notch edges and curving into a bowl-shaped structure. The sequence of formation of notches followed by the structure relaxation finally leads to folding of the graphene flake into the fullerene. It should be emphasized that etching of graphene flakes by an electron beam is crucial for the transformation to fullerenes at low temperatures. It should also be noted that fullerenes obtained in this way can contain structural defects such as polygons other than hexagons and pentagons. Below we use the term “fullerene” not only in the narrow sense for perfect fullerenes, i.e., carbon cages consisting of three-coordinated carbon atoms arranged in hexagons and pentagons, but also for fullerenes incorporating structural defects."
Micelotta, E. R., Jones, A. P., Cami, J., Peeters, E., Bernard-Salas, J., & Fanchini, G. (2012), The formation of cosmic fullerenes from arophatic clusters. The Astrophysical Journal, 761: 35, doi: 10.1088/0004-637X/761/1/35, Citation: "."
Ming, C., Lin, Z. Z., Cao, R. G., Yu, W. F., & Ning, X. J. (2012), A scheme for fabricating single wall carbon nanocones standing on metal surfaces and an evaluation of their stability. Carbon, 50: 2651-2656, doi: 10.1016/j.carbon.2012.02.025, Citation: "The tailored sheet can also be desorbed from substrates by gas blowing the metal surface and forms a single wall carbon nanocone (SWCNC) spontaneously [Figure]. This method can precisely control the sizes and cone angles of SWCNC as long as the graphene sheet is precisely tailored by microscopic techniques, such as the ion beam lithography whose patterning ability on the nanometer-scale has been demonstrated. The patterning ability of this technique has been demonstrated on the accuracy of nanometers. Then by extrapolating the barrier hopping equation, it shows that the cone will quickly change into a sphere (within 0.33 ms) at 1000 K, which may explain the quick transition from small carbon bowls to fullerenes."
Ming, C., Lin, Z. Z., Zhuang, J., & Ning, X. J. (2012), Electronic rectification devices from carbon nanocones. Applied Physics Letters, 100: 063119, doi: 10.1063/1.3684276 , Citation: "This fact suggests that we can tailor a graphene sheet into a desired cone sheet on Ni substrate via ion beam etching."
Nishida, J. I., Tsukaguchi, S., & Yamashita, Y. (2012), Synthesis, Crystal Structures, and Properties of 6, 12-Diaryl-Substituted Indeno [1, 2-b] fluorenes. Chemistry-A European Journal, 18: 8964-8970, doi: 10.1002/chem.201200591, Citation: "Polycyclic fused p-conjugated compounds show redox-active properties that can be used for nanotechnology."
Pantelic, R. S., Meyer, J. C., Kaiser, U., & Stahlberg, H. (2012), The application of Graphene as a sample support in Transmission Electron Microscopy. Solid State Communications, 152: 1375-1382, doi: , Citation: Importantly, high-resolution, high-signal-to-noise ratio images of small clusters of light-element contamination, indicate that similar quality high-resolution images might be obtained from small molecular clusters that will require controlled deposition across a clean graphene support."
Quintana, M., Grzelczak, M., Spyrou, K., Calvaresi, M., Bals, S., Kooi, B., van Van Tendeloo, G., Rudolf, P., Zerbetto, F., & Prato, M. (2012), A Simple Road for the Transformation of Few-Layer Graphene into MWNTs. Journal of the American Chemical Society, 134: 13310-13315, doi: , Citation: "Recently, in situ TEM experiments demonstrated the direct transformation of flat graphene sheets into fullerene cages where etching of the edge carbon atoms promotes folding into fullerenes."
Roberts, K. R., Smith, K. T., & Sarre, P. J. (2012), Detection of C60 in embedded young stellar objects, a Herbig Ae/Be star and an unusual post-asymptotic giant branch star. Monthly Notices of the Royal Astronomical Society, 421: 3277-3285, doi: 10.1111/j.1365-2966.2012.20552.x, Citation: "Chuvilin et al. (2010) have recently shown that under highly energetic conditions small PAH-like graphene sheets can undergo rearrangement to form fullerenes. The laboratory experiments of Chuvilin et al. (2010) were conducted using transmission electron microscopy in which very high energy electrons induce dehydrogenation and loss of carbon atoms leading to C60 formation. Chuvilin et al. (2010) have seen the ‘top–down’ formation of C60 from PAHs."
Santana, A., Popov, A. M., & Bichoutskaia, E. (2012), Stability and dynamics of vacancy in graphene flakes: Edge effects. Chemical Physics Letters, 557: 80-87, doi: 10.1016/j.cplett.2012.11.077, Citation: "Based on AC-TEM observations of transformation of small finite graphene flake into fullerene, a new ‘top-down’ mechanism for the formation of fullerene under the electron beam radiation has been proposed. The critical step in the proposed ‘top-down’ mechanism of the fullerene formation is creation of vacancies in small graphene flake as a result of knock-on damage by electrons of the imaging electron beam (e-beam). The subsequent formation of pentagons at the vacancy sites near the edge reduces the number of dangling bonds and triggers the curving process of graphene flake into a closed fullerene structure. Thus, dynamic behaviour of vacancies near graphene edge plays a crucial role in explaining mechanisms of the e-beam assisted self-assembly and structural transformations in graphene-like structures. The presented calculations underpin the mechanisms driving structural transformations in graphene, which have been observed recently in AC-TEM experiments. In the proposed ‘top-down’ mechanism for fullerene formation directly from a flat graphene flake in AC-TEM, the initial size of the graphene flake is important as it determines the size of the formed fullerene cage. In large extended flakes the van der Waals interaction between the substrate and the flake prevents the structure transformation. The edges of large flakes continue to be etched by the electron beam until the flake reaches an optimal size of about 150–300 atoms enabling the thermodynamically driven closure of fullerene cage."
Tappe, A., Rho, J., Boersma, C., & Micelotta, E. R. (2012), Polycyclic Aromatic Hydrocarbon Processing in the Blast Wave of the Supernova Remnant N132D. The Astrophysical Journal, 754: 132, doi: 10.1088/0004-637X/754/2/132, Citation: "."
Terrones, H., Lv, R., Terrones, M., & Dresselhaus, M. S. (2012), The role of defects and doping in 2D graphene sheets and 1D nanoribbons. Reports on Progress in Physics, 75: 062501, doi: 10.1088/0034-4885/75/6/062501, Citation: "In 2010, Chuvilin and colleagues showed the transformation of a graphene surface into a fullerene using a transmission electron microscope, thus showing that fullerenes are indeed a metastable state of graphene. In summary, one could transform graphene into fullerenes, graphene into nanotubes, fullerenes into nanotubes or nanotubes into graphene nanoribbons. These transformations are all possible and have been demonstrated from both a theoretical and experimental standpoint."
Uberuaga, B. P., Stuart, S. J., Windl, W., Masquelier, M. P., & Voter, A. F. (2012), Fullerene and graphene formation from carbon nanotube fragments. Computational and Theoretical Chemistry, 987: 115-121, doi: 10.1016/j.comptc.2011.11.030, Citation: "Recently, it has been suggested based on electron microscopy and accompanying total-energy calculations for the observed structures that formation of pentagons around the undercoordinated edges results from rearrangements to eliminate dangling bonds."
Yamazaki, K., Niitsu, N., Nakamura, K., Kanno, M., & Kono, H. (2012), Electronic Excited State Paths of Stone-Wales Rearrangement in Pyrene: Roles of Conical Intersections. Journal of Physical Chemistry A, 116: 11441-11450, doi: 10.1021/jp306894x, Citation: "Stone−Wales rearrangement is essential for C60 formation from graphene to reduce the distortions on carbon bond networks by creating five membered rings."
Zoberbier, T., Chamberlain, T. W., Biskupek, J., Kuganathan, N., Eyhusen, S., Bichoutskaia, E., Kaiser, U. A., & Khlobystov, A. N. (2012), Interactions and reactions of transition metal clusters with the interior of single-walled carbon nanotubes imaged at the atomic scale. Journal of the American Chemical Society, 134: 3073-3079, doi: 10.1021/ja208746z, Citation: "While conventional spectroscopic methods that integrate over larger volumes (e.g., XPS, Raman, etc.) can be applied for characterizing the bulk physicochemical properties, high-resolution transmission electron microscopy (HRTEM) is now rapidly becoming an excellent local-probe tool for studying chemical reactions in nanotubes by imaging transformations in direct space and real time down to the single-atom level. We have previously demonstrated that the formation of closed graphitic structures is facilitated by the e-beam through the loss of edge carbon atoms and the formation of pentagons providing the curvature required for a closed structure."
Chamberlain, T. W., Meyer, J. C., Biskupek, J., Leschner, J., Santana, A., Besley, N. A., Bichoutskaia, E., Kaiser, U., & Khlobystov, A. N. (2011), Reactions of the inner surface of carbon nanotubes and nanoprotrusion processes imaged at the atomic scale. Nature Chemistry, 3: 732-737, doi: 10.1038/nchem.1115, Citation: "The unlimited and fast supply of carbon to the growing edge of the protrusion could, in principle, lead to the formation of a nanotube-like ‘tentacle’ attached to the parent SWNT. However, we found that the growth of the protrusion is limited by the curvature imposed by the dangling bond minimization requirement, similar to the mechanism that drives the formation of fullerenes from graphene."
Darwish, A. D. (2011), Fullerenes. Annual Reports Section A, 107: 473-489, doi: 10.1039/C1IC90014E, Citation: "A process of fullerene formation from a graphene sheet has been visualised with an aberration-corrected transmission electron microscope. Quantum chemical modelling explains four critical steps in the mechanism of fullerene formation."
Gomes Santos, E. J. (2011), First-principles study of the electronic and magnetic properties of defective carbon nanostructures, PhD dissertation Universidad del Pais Vasco, doi: PDF, Citation: "For instance, fullerenes can be generated from graphene by introducting pentagons that create positive curvature defects, and hence fullerenes can be thought as a 0D nanocarbon. Although this idea seems to be simple, the experimental route to form these carbon cages from a flat graphene sheet is still a topic of research."
Kaiser, U. (2011), Imaging and Spectroscopy of Carbon Nanostructures with 80 and 20 keV Electrons. Microscopy and Microanalysis, 17: 1488-1489, doi: 10.1017/S1431927611008312, Citation: "The remarkable physical properties of graphene depend directly on the atomic defect structure. Under special circumstances it begets other carbon nanostructures, e. g. fullerenes."
Karthik, C., Kane, J., Butt, D. P., Windes, W. E., & Ubic, R. (2011), In situ transmission electron microscopy of electron-beam induced damage process in nuclear grade graphite. Journal of Nuclear Materials, 412: 321-326, doi: 10.1016/j.jnucmat.2011.03.024, Citation: "Recently, Chuvlin et al. have shown in real-time the fullerene formation from a graphene sheet under electron irradiation."
Kotakoski, J., Santos-Cottin, D., & Krasheninnikov, A. V. (2011), Stability of Graphene Edges under Electron Beam: Equilibrium Energetics versus Dynamic Effects. ACS nano, 6:, 671-676, doi: 10.1021/nn204148h, Citation: "It has been demonstrated that the electron beam can also be used for transforming a graphene flake into a fullerene."
Li, H., Zhang, Y., Wu, T., Liu, S., Wang, L., & Sun, X. (2011), Carbon nanospheres for fluorescent biomolecular detection. Journal of Materials Chemistry, 21: 4663-4668, doi: 10.1039/C0JM04107F, Citation: "Then, the resultant graphene sheets dissociate into very small clusters of carbon atoms with the aid of ultrasonication."
Lu, J., Yeo, P. S. E., Gan, C. K., Wu, P., & Loh, K. P. (2011), Transforming C60 molecules into graphene quantum dots. Nature Nanotechnology, 6: 247-252, doi: 10.1038/nnano.2011.30, Citation: "Graphene has been directly transformed into fullerene."
Lv, W., Tao, Y., Ni, W., Zhou, Z., Su, F. Y., Chen, X. C., Jin, F. M., & Yang, Q. H. (2011), One-pot self-assembly of three-dimensional graphene macroassemblies with porous core and layered shell. J. Mater. Chem., 21: 12352-12357, doi: 10.1039/C1JM11728A, Citation: "Only a few reports have shown the transformation of graphene to fullerenes and nanotubes."
Mendez, J., Lopez, M. F., & Martín-Gago, J. A. (2011), On-surface synthesis of cyclic organic molecules. Chemical Society Reviews, 40: 4578-4590, doi: 10.1039/C0CS00161A, Citation: "It is known that a strictly 2D system is thermodynamically unstable and it will tend to attain a third dimension spontaneously."
Porrati, F., Sachser, R., Schwalb, C. H., Frangakis, A. S., & Huth, M. (2011), Tuning the electrical conductivity of Pt-containing granular metals by postgrowth electron irradiation. Journal of Applied Physics, 109: 063715, doi: 10.1063/1.3559773, Citation: "For instance, the morphology of carbon nanotubes, graphene, and fullerene can be controlled by electron beam irradiation."
Saha, B., Irle, S., & Morokuma, K. (2011), Hot Giant Fullerenes Eject and Capture C2 Molecules: QM/MD Simulations with Constant Density. Journal of Physical Chemistry C, 115: 22707-22716, doi: 10.1021/jp203614e, Citation: "Although thermal shrinking has been established as a widely accepted mechanism, recent HRTEM observations of direct fullerene formation from a graphene flake are seemingly at odds with the shrinking hot giant road."
Schaffel, F., Wilson, M., & Warner, J. H. (2011), Motion of Light Adatoms and Molecules on the Surface of Few-Layer Graphene. ACS nano, 5: 9428-9441, doi: 10.1021/nn2036494, Citation: "HRTEM studies of adatoms and molecules on surfaces are rare. The recent developments in producing ultrathin two-dimensional membranes as TEM supports have expedited HRTEM investigations of molecules."
Schebarchov, D., Hendy, S. C., Ertekin, E., & Grossman, J. C. (2011), Interplay of Wetting and Elasticity in the Nucleation of Carbon Nanotubes. Physical Review Letters, 107: 185503, doi: 10.1103/PhysRevLett.107.185503, Citation: "We stress that the key ansatz of our continuum model is the introduction of spontaneous curvature re-1, which was simply inferred from molecular dynamics simulations to inform. We interpret re as an effective parameter that also includes edge effects: It represents the mean (positive) curvature due to pentagonal rings, which can reduce the number of (catalyst-stabilized) dangling bonds in a graphene flake."
Snook, I., & Barnard, A. (2011), Theory, experiment and applications of graphene nano-flakes. Journal of Nanoscience Letters, 1: 50-60, doi: PDF, Citation: "Naturally, top-down synthesis necessitates the initial production of graphene membranes, which may be done by chemically "unzipping" carbon nanotubes or fullerenes."
Uberuaga, B. P., Stuartb, S. J., Windl, W., Masquelier, M. P., & Voter, A. F. (2011), Fullerene and graphene formation from carbon nanotube fragments, Computational and Theoretical Chemistry, 987: 115-121, doi: 10.1016/j.comptc.2011.11.030, Citation: "Recently, it has been suggested based on electron microscopy and accompanying total-energy calculations for the observed structures that formation of pentagons around the undercoordinated edges results from rearrangements to eliminate dangling bonds."
Zhan, D., Liu, L., Xu, Y. N., Ni, Z. H., Yan, J. X., Zhao, C., & Shen, Z. X. (2011), Low temperature edge dynamics of AB-stacked bilayer graphene: Naturally favored closed zigzag edges. Scientific reports, 1, doi: 10.1038/srep00012, Citation: "Graphene with edges, so called graphene nanoribbons (GNRs), have been intensively studied."
Bayley, H. (2010), Nanotechnology: holes with an edge. Nature, 467: 164-165, doi: 10.1038/467164a, Citation: "Or maybe the electron beam that creates the pores induces structural reorganization of the peripheral groups, generating new configurations such as five-membered rings."
Du, A., & Smith, S. C. (2010), Electronic functionality in graphene-based nanoarchitectures: discovery and design via first-principles modeling. Journal of Physical Chemistry Letters, 2: 73-80, doi: 10.1021/jz101347a, Citation: "Recent experimental observations show the closure of graphite edges and formation of fullerenes directly from graphene fragments."
Golberg, D., Bando, Y., Huang, Y., Xu, Z., Wei, X., Bourgeois, L., Wang, M. S., Zeng, H., Lin, J., & Zhi, C. (2010), Recent advances in boron nitride nanotubes and nanosheets. Israel Journal of Chemistry, 50: 405-416, doi: 10.1002/ijch.201000049, Citation: "."
Kim, D., Kim, E., Lee, J., Hong, S., Sung, W., Lim, N., Park, C. G., & Kim, K. (2010), Direct synthesis of polymer nanocapsules: self-assembly of polymer hollow spheres through irreversible covalent bond formation. Journal of the American Chemical Society, 132: 9908-9919, doi: 10.1021/ja1039242, Citation: "After submission of this paper, the direct transformation of graphene to fullerene, which is conceptually similar to the conversion of a 2D oligomeric patch into a nanocapsule as described here, was reported."
Martinez, J. C., Jalil, M. B. A., & Tan, S. G. (2010), Klein tunneling and zitterbewegung and the formation of a polarized< equation> pn junction in graphene. Applied Physics Letters, 97: 062111, doi: 10.1063/1.3467675 , Citation: "The dipolar polarization functions as a signature of trembling transverse motion (ZBW) may find application in the formation of fullerenes and carbon nanotubes. The difficulty of verifying experimentally the exponential collimation of ballistic carriers passing through monolayer graphene p-n junctions is well-known."
Shenoy, V. B., Reddy, C. D., & Zhang, Y. W. (2010), Spontaneous curling of graphene sheets with reconstructed edges. ACS nano, 4: 4840-4844, doi: 10.1021/nn100842k, Citation: "While this article was under review, a report appeared of the observation of spontaneous curving of graphene flakes due to formation of pentagon rings at the edges similar to the cases considered in our work."
Vaughan, O. (2010), Fullerene synthesis: Caught on camera. Nature nanotechnology, 5: 386-386, doi: 10.1038/nnano.2010.117, Citation: "Graphite is routinely transformed into fullerene C60 molecules with the help of lasers or electric arcs, although the exact mechanism by which these spherical carbon structures are formed is still unclear. Andrey Chuvilin, Andrei Khlobystov and colleagues at the universities of Ulm and Nottingham have now directly imaged the formation of fullerene molecules from graphene (a single layer of carbon atoms) with an aberration-corrected transmission electron microscope (Nature Chem. 2, 450–453; 2010), The Ulm–Nottingham team fired an 80-keV electron beam at their starting material, exciting the carbon atoms and fragmenting the graphene sheet into smaller flakes. These flakes underwent a series of further changes before finally forming a spherical fullerene molecule that seemed to roll back and forth on the graphene substrate below. The highresolution imaging was supplemented with quantum mechanical modelling, which helped the team determine the formation mechanism.
The [Figure] shows models (top) and simulated electron-microscopy images (bottom) of key stages in the mechanism. Chuvilin, who is now at the nanoGUNE laboratory in Spain, and colleagues found that the electron beam removed carbon atoms from the edges of the graphene flakes (left), destabilizing the flakes and leading to the formation of pentagons (middle-left). This in turn caused the flakes to curl and form bowl-shaped structures (middleright). Finally, the edges of the flakes were ‘zipped up’ to yield the fullerene molecules (right). The conditions under which these molecules were formed is markedly different from those normally used for fullerene production, so 25 years after C60 was first produced in the laboratory, there is still more to learn about the mechanisms used to produce it."
Gomez-Navarro, C., J. C. Meyer, R. S. Sundaram, A. Chuvilin, S. Kurasch, M. Burghard, K. Kern, U. A. Kaiser (2010), Atomic Structure of Reduced Graphene Oxide. Nano Lett., 10: 1144-1148, doi: 10.1021/nl9031617. Cited by (186)
Biro, L. P., & Lambin, P. (2013), Grain boundaries in graphene grown by chemical vapor deposition. New Journal of Physics, 15: 035024, doi: 10.1088/1367-2630/15/3/035024, Citation: "Recent experimental results obtained by aberration corrected-HRTEM (AC-HRTEM) confirm that a-C is a stable structure even when it is one atom thick, and contains a significant quantity of topological defects, like observed in reduced graphene oxide. These can be further classified into isolated topological defects (pentagon–heptagon pairs), and extended (clustered) topological defects that appear as quasi-amorphous single-layer carbon structures. Another relevant observation is that the graphene regions in the vicinity of these clustered defects can be highly distorted. These distortions are typically limited to areas immediately adjacent to the defect clusters, while the larger defect-free graphene areas appear undistorted."
Chang, H. C., Li, C. C., Jen, S. F., Lu, C. C., Bu, I. Y. Y., Chiu, P. W., & Lee, K. Y. (2013), All-carbon field em
2021
Najafidehaghani, E.; Gan, Z.; George, A.; Lehnert, T.; Ngo, G. Q.; Neumann, C.; Bucher, T.; Staude, I.; Kaiser, D.; Vogl, T.; Hübner, U.; Kaiser, U.; Eilenberger, F.; Turchanin, A. (2021) 1D p–n Junction Electronic and Optoelectronic Devices from Transition Metal Dichalcogenide Lateral Heterostructures Grown by One-Pot Chemical Vapor Deposition Synthesis. Advanced Functional Materials 31, 27, 2101086. http://dx.doi.org/https://doi.org/10.1002/adfm.202101086.
Ma, Y.; Ma, Y.; Diemant, T.; Cao, K.; Kaiser, U.; Behm, R. J.; Varzi, A.; Passerini, S. (2021) Embedding Heterostructured α-MnS/MnO Nanoparticles in S-Doped Carbonaceous Porous Framework as High-Performance Anode for Lithium-Ion Batteries. ChemElectroChem 8, 5, 918-927. http://dx.doi.org/https://doi.org/10.1002/celc.202100110.
Liu, K.; Li, J.; Qi, H.; Hambsch, M.; Rawle, J.; Vázquez, A. R.; Nia, A. S.; Pashkin, A.; Schneider, H.; Polozij, M.; Heine, T.; Helm, M.; Mannsfeld, S. C. B.; Kaiser, U.; Dong, R.; Feng, X. (2021) A Two-Dimensional Polyimide-Graphene Heterostructure with Ultra-fast Interlayer Charge Transfer. Angewandte Chemie International Edition 60, 25, 13859-13864. http://dx.doi.org/https://doi.org/10.1002/anie.202102984.
Kuzmany, H.; Shi, L.; Martinati, M.; Cambré, S.; Wenseleers, W.; Kürti, J.; Koltai, J.; Kukucska, G.; Cao, K.; Kaiser, U.; Saito, T.; Pichler, T. (2021) Well-defined sub-nanometer graphene ribbons synthesized inside carbon nanotubes. Carbon 171, 221-229. http://dx.doi.org/https://doi.org/10.1016/j.carbon.2020.08.065.
Kuzmany, H.; Shi, L.; Martinati, M.; Cambré, S.; Wenseleers, W.; Kürti, J.; Koltai, J.; Kukucska, G.; Cao, K.; Kaiser, U.; Saito, T.; Pichler, T. (2021) Well-defined sub-nanometer graphene ribbons synthesized inside carbon nanotubes. Carbon 171, 221-229. http://dx.doi.org/https://doi.org/10.1016/j.carbon.2020.08.065.
Köster, J.; Ghorbani-Asl, M.; Komsa, H.-P.; Lehnert, T.; Kretschmer, S.; Krasheninnikov, A. V.; Kaiser, U. (2021) Defect Agglomeration and Electron-Beam-Induced Local-Phase Transformations in Single-Layer MoTe2. The Journal of Physical Chemistry C 125, 24, 13601-13609. http://dx.doi.org/10.1021/acs.jpcc.1c02202.
Kinyanjui, M. K.; Holzbock, J.; Köster, J.; Singer, C.; Krottenmüller, M.; Linden, M.; Kuntscher, C. A.; Kaiser, U. (2021) Spectral and structural signatures of phase transformation in the charge density wave material $1T\text{\ensuremath{-}}\mathrm{Ta}{\mathrm{S}}_{2}$ intercalated with triethylenediamine. Physical Review B 103, 6, 064101. http://dx.doi.org/10.1103/PhysRevB.103.064101.
Jordan, J. W.; Fung, K. L. Y.; Skowron, S. T.; Allen, C. S.; Biskupek, J.; Newton, G. N.; Kaiser, U.; Khlobystov, A. N. (2021) Single-molecule imaging and kinetic analysis of intermolecular polyoxometalate reactions. Chemical Science 12, 21, 7377-7387. http://dx.doi.org/10.1039/D1SC01874D.
Jiang, L.; van Deursen, P. M. G.; Arjmandi-Tash, H.; Belyaeva, L. A.; Qi, H.; He, J.; Kofman, V.; Wu, L.; Muravev, V.; Kaiser, U.; Linnartz, H.; Hensen, E. J. M.; Hofmann, J. P.; Schneider, G. F. (2021) Reversible hydrogenation restores defected graphene to graphene. Science China Chemistry 64, 6, 1047-1056. http://dx.doi.org/10.1007/s11426-020-9959-5.
Jiang, L.; van Deursen, P. M. G.; Arjmandi-Tash, H.; Belyaeva, L. A.; Qi, H.; He, J.; Kofman, V.; Wu, L.; Muravev, V.; Kaiser, U.; Linnartz, H.; Hensen, E. J. M.; Hofmann, J. P.; Schneider, G. F. (2021) Reversible hydrogenation restores defected graphene to graphene. Science China Chemistry 64, 6, 1047-1056. http://dx.doi.org/10.1007/s11426-020-9959-5.
George, A.; Fistul, M. V.; Gruenewald, M.; Kaiser, D.; Lehnert, T.; Mupparapu, R.; Neumann, C.; Hübner, U.; Schaal, M.; Masurkar, N.; Arava, L. M. R.; Staude, I.; Kaiser, U.; Fritz, T.; Turchanin, A. (2021) Giant persistent photoconductivity in monolayer MoS2 field-effect transistors. npj 2D Materials and Applications 5, 1, 15. http://dx.doi.org/10.1038/s41699-020-00182-0.
2020
Xing, X.; Liu, R.; Anjass, M.; Cao, K.; Kaiser, U.; Zhang, G.; Streb, C. (2020) Bimetallic manganese-vanadium functionalized N,S-doped carbon nanotubes as efficient oxygen evolution and oxygen reduction electrocatalysts. Applied Catalysis B: Environmental 277, 119195. http://dx.doi.org/https://doi.org/10.1016/j.apcatb.2020.119195.
Wang, Z.; Yao, Q.; Neumann, C.; Börrnert, F.; Renner, J.; Kaiser, U.; Turchanin, A.; Zandvliet, H. J. W.; Eigler, S. (2020) Identification of Semiconductive Patches in Thermally Processed Monolayer Oxo-Functionalized Graphene. Angewandte Chemie International Edition 59, 32, 13657-13662. http://dx.doi.org/https://doi.org/10.1002/anie.202004005.
Rajagopal, A.; Akbarzadeh, E.; Li, C.; Mitoraj, D.; Krivtsov, I.; Adler, C.; Diemant, T.; Biskupek, J.; Kaiser, U.; Im, C.; Heiland, M.; Jacob, T.; Streb, C.; Dietzek, B.; Beranek, R. (2020) Polymeric carbon nitride coupled with a molecular thiomolybdate catalyst: exciton and charge dynamics in light-driven hydrogen evolution. Sustainable Energy & Fuels 4, 12, 6085-6095. http://dx.doi.org/10.1039/D0SE01366H.
Mohn, M. J.; Biskupek, J.; Lee, Z.; Rose, H.; Kaiser, U. (2020) Lattice contrast in the core-loss EFTEM signal of graphene. Ultramicroscopy 219, 113119. http://dx.doi.org/https://doi.org/10.1016/j.ultramic.2020.113119.
Ma, Y.; Ma, Y.; Giuli, G.; Euchner, H.; Groß, A.; Lepore, G. O.; d'Acapito, F.; Geiger, D.; Biskupek, J.; Kaiser, U.; Schütz, H. M.; Carlsson, A.; Diemant, T.; Behm, R. J.; Kuenzel, M.; Passerini, S.; Bresser, D. (2020) Introducing Highly Redox-Active Atomic Centers into Insertion-Type Electrodes for Lithium-Ion Batteries. Advanced Energy Materials 10, 25, 2000783. http://dx.doi.org/https://doi.org/10.1002/aenm.202000783.
Liu, R.; Cao, K.; Clark, A. H.; Lu, P.; Anjass, M.; Biskupek, J.; Kaiser, U.; Zhang, G.; Streb, C. (2020) Top-down synthesis of polyoxometalate-like sub-nanometer molybdenum-oxo clusters as high-performance electrocatalysts. Chemical Science 11, 4, 1043-1051. http://dx.doi.org/10.1039/C9SC05469C.
Liu, R.; Anjass, M.; Greiner, S.; Liu, S.; Gao, D.; Biskupek, J.; Kaiser, U.; Zhang, G.; Streb, C. (2020) Bottom-up Design of Bimetallic Cobalt–Molybdenum Carbides/Oxides for Overall Water Splitting. Chemistry – A European Journal 26, 18, 4157-4164. http://dx.doi.org/https://doi.org/10.1002/chem.201905265.
Leiter, R.; Li, Y.; Kaiser, U. (2020) In-situ formation and evolution of atomic defects in monolayer WSe2 under electron irradiation. Nanotechnology 31, 49, 495704. http://dx.doi.org/10.1088/1361-6528/abb335.
Leiter, R.; Li, Y.; Kaiser, U. (2020) In-situ formation and evolution of atomic defects in monolayer WSe2 under electron irradiation. Nanotechnology 31, 49, 495704. http://dx.doi.org/10.1088/1361-6528/abb335.
Kretschmer, S.; Lehnert, T.; Kaiser, U.; Krasheninnikov, A. V. (2020) Formation of Defects in Two-Dimensional MoS2 in the Transmission Electron Microscope at Electron Energies below the Knock-on Threshold: The Role of Electronic Excitations. Nano Letters 20, 4, 2865-2870. http://dx.doi.org/10.1021/acs.nanolett.0c00670.
Köster, J.; Liang, B.; Storm, A.; Kaiser, U. (2020) Polymer-assisted TEM specimen preparation method for oxidation-sensitive 2D materials. Nanotechnology 32, 7, 075704. http://dx.doi.org/10.1088/1361-6528/abc49e.
Köster, J.; Lehnert, T.; Ghorbani-Asl, M.; Kretschmer, S.; Komsa, H.-P.; Krasheninnikov, A.; Kaiser, U. (2020) Electron-beam-stimulated Atomic Migration Processes in Single-layer MoTe2. Microscopy and Microanalysis 26, S2, 534-537. http://dx.doi.org/10.1017/S1431927620014981.
Han, J.; Zarrabeitia, M.; Mariani, A.; Jusys, Z.; Hekmatfar, M.; Zhang, H.; Geiger, D.; Kaiser, U.; Behm, R. J.; Varzi, A.; Passerini, S. (2020) Halide-free water-in-salt electrolytes for stable aqueous sodium-ion batteries. Nano Energy 77, 105176. http://dx.doi.org/https://doi.org/10.1016/j.nanoen.2020.105176.
Griffin, E.; Mogg, L.; Hao, G.-P.; Kalon, G.; Bacaksiz, C.; Lopez-Polin, G.; Zhou, T. Y.; Guarochico, V.; Cai, J.; Neumann, C.; Winter, A.; Mohn, M.; Lee, J. H.; Lin, J.; Kaiser, U.; Grigorieva, I. V.; Suenaga, K.; Özyilmaz, B.; Cheng, H.-M.; Ren, W.; Turchanin, A.; Peeters, F. M.; Geim, A. K.; Lozada-Hidalgo, M. (2020) Proton and Li-Ion Permeation through Graphene with Eight-Atom-Ring Defects. ACS Nano 14, 6, 7280-7286. http://dx.doi.org/10.1021/acsnano.0c02496.
Cao, K.; Skowron, S. T.; Stoppiello, C. T.; Biskupek, J.; Khlobystov, A. N.; Kaiser, U. (2020) Direct Imaging of Atomic Permeation Through a Vacancy Defect in the Carbon Lattice. Angewandte Chemie International Edition 59, 51, 22922-22927. http://dx.doi.org/https://doi.org/10.1002/anie.202010630.
Cao, K.; Skowron, S. T.; Biskupek, J.; Stoppiello, C. T.; Leist, C.; Besley, E.; Khlobystov, A. N.; Kaiser, U. (2020) Imaging an unsupported metal–metal bond in dirhenium molecules at the atomic scale. Science Advances 6, 3, eaay5849. http://dx.doi.org/10.1126/sciadv.aay5849.
Cao, K.; Biskupek, J.; Stoppiello, C. T.; McSweeney, R. L.; Chamberlain, T. W.; Liu, Z.; Suenaga, K.; Skowron, S. T.; Besley, E.; Khlobystov, A. N.; Kaiser, U. (2020) Atomic mechanism of metal crystal nucleus formation in a single-walled carbon nanotube. Nat Chem 12, 10, 921-928. http://dx.doi.org/10.1038/s41557-020-0538-9.
Biskupek, J.; Skowron, S. T.; Stoppiello, C. T.; Rance, G. A.; Alom, S.; Fung, K. L. Y.; Whitby, R. J.; Levitt, M. H.; Ramasse, Q. M.; Kaiser, U.; Besley, E.; Khlobystov, A. N. (2020) Bond Dissociation and Reactivity of HF and H2O in a Nano Test Tube. ACS Nano 14, 9, 11178-11189. http://dx.doi.org/10.1021/acsnano.0c02661.
Balakrishna, B.; Menon, A.; Cao, K.; Gsänger, S.; Beil, S. B.; Villalva, J.; Shyshov, O.; Martin, O.; Hirsch, A.; Meyer, B.; Kaiser, U.; Guldi, D. M.; von Delius, M. (2020) Dynamic Covalent Formation of Concave Disulfide Macrocycles Mechanically Interlocked with Single-Walled Carbon Nanotubes. Angewandte Chemie International Edition 59, 42, 18774-18785. http://dx.doi.org/https://doi.org/10.1002/anie.202005081.
Backes, C.; Abdelkader, A. M.; Alonso, C.; Andrieux-Ledier, A.; Arenal, R.; Azpeitia, J.; Balakrishnan, N.; Banszerus, L.; Barjon, J.; Bartali, R.; Bellani, S.; Berger, C.; Berger, R.; Ortega, M. M. B.; Bernard, C.; Beton, P. H.; Beyer, A.; Bianco, A.; Bøggild, P.; Bonaccorso, F.; Barin, G. B.; Botas, C.; Bueno, R. A.; Carriazo, D.; Castellanos-Gomez, A.; Christian, M.; Ciesielski, A.; Ciuk, T.; Cole, M. T.; Coleman, J.; Coletti, C.; Crema, L.; Cun, H.; Dasler, D.; De Fazio, D.; Díez, N.; Drieschner, S.; Duesberg, G. S.; Fasel, R.; Feng, X.; Fina, A.; Forti, S.; Galiotis, C.; Garberoglio, G.; García, J. M.; Garrido, J. A.; Gibertini, M.; Gölzhäuser, A.; Gómez, J.; Greber, T.; Hauke, F.; Hemmi, A.; Hernandez-Rodriguez, I.; Hirsch, A.; Hodge, S. A.; Huttel, Y.; Jepsen, P. U.; Jimenez, I.; Kaiser, U.; Kaplas, T.; Kim, H.; Kis, A.; Papagelis, K.; Kostarelos, K.; Krajewska, A.; Lee, K.; Li, C.; Lipsanen, H.; Liscio, A.; Lohe, M. R.; Loiseau, A.; Lombardi, L.; Francisca López, M.; Martin, O.; Martín, C.; Martínez, L.; Martin-Gago, J. A.; Ignacio Martínez, J.; Marzari, N.; Mayoral, Á.; McManus, J.; Melucci, M.; Méndez, J.; Merino, C.; Merino, P.; Meyer, A. P.; Miniussi, E.; Miseikis, V.; Mishra, N.; Morandi, V.; Munuera, C.; Muñoz, R.; Nolan, H.; Ortolani, L.; Ott, A. K.; Palacio, I.; Palermo, V.; Parthenios, J.; Pasternak, I.; Patane, A.; Prato, M.; Prevost, H.; Prudkovskiy, V.; Pugno, N.; Rojo, T.; Rossi, A.; Ruffieux, P.; Samorì, P.; Schué, L.; Setijadi, E.; Seyller, T.; Speranza, G.; Stampfer, C.; Stenger, I.; Strupinski, W.; Svirko, Y.; Taioli, S.; Teo, K. B. K.; Testi, M.; Tomarchio, F.; Tortello, M.; Treossi, E.; Turchanin, A.; Vazquez, E.; Villaro, E.; Whelan, P. R.; Xia, Z.; Yakimova, R.; Yang, S.; Yazdi, G. R.; Yim, C.; Yoon, D.; Zhang, X.; Zhuang, X.; Colombo, L.; Ferrari, A. C.; Garcia-Hernandez, M. (2020) Production and processing of graphene and related materials. 2D Materials 7, 2, 022001. http://dx.doi.org/10.1088/2053-1583/ab1e0a.
Asenbauer, J.; Binder, J. R.; Mueller, F.; Kuenzel, M.; Geiger, D.; Kaiser, U.; Passerini, S.; Bresser, D. (2020) Scalable Synthesis of Microsized, Nanocrystalline Zn0.9Fe0.1O-C Secondary Particles and Their Use in Zn0.9Fe0.1O-C/LiNi0.5Mn1.5O4 Lithium-Ion Full Cells. ChemSusChem 13, 13, 3504-3513. http://dx.doi.org/https://doi.org/10.1002/cssc.202000559.
2019
Xu, Y.; Bahmani, F.; Zhou, M.; Li, Y.; Zhang, C.; Liang, F.; Kazemi, S. H.; Kaiser, U.; Meng, G.; Lei, Y. (2019) Enhancing potassium-ion battery performance by defect and interlayer engineering. Nanoscale Horizons 4, 1, 202-207. http://dx.doi.org/10.1039/C8NH00305J.
Xing, X.; Liu, R.; Cao, K.; Kaiser, U.; Streb, C. (2019) Transition-Metal Oxides/Carbides@Carbon Nanotube Composites as Multifunctional Electrocatalysts for Challenging Oxidations and Reductions. Chemistry – A European Journal 25, 47, 11098-11104. http://dx.doi.org/https://doi.org/10.1002/chem.201901400.
van Deursen, P. M. G.; Tang, Z.; Winter, A.; Mohn, M. J.; Kaiser, U.; Turchanin, A. A.; Schneider, G. F. (2019) Selective ion sieving through arrays of sub-nanometer nanopores in chemically tunable 2D carbon membranes. Nanoscale 11, 43, 20785-20791. http://dx.doi.org/10.1039/C9NR05537A.
Shree, S.; George, A.; Lehnert, T.; Neumann, C.; Benelajla, M.; Robert, C.; Marie, X.; Watanabe, K.; Taniguchi, T.; Kaiser, U.; Urbaszek, B.; Turchanin, A. (2019) High optical quality of MoS 2 monolayers grown by chemical vapor deposition. 2D Materials 7, 1, 015011. http://dx.doi.org/10.1088/2053-1583/ab4f1f.
Neumann, C.; Kaiser, D.; Mohn, M. J.; Füser, M.; Weber, N.-E.; Reimer, O.; Gölzhäuser, A.; Weimann, T.; Terfort, A.; Kaiser, U.; Turchanin, A. (2019) Bottom-Up Synthesis of Graphene Monolayers with Tunable Crystallinity and Porosity. ACS Nano 13, 6, 7310-7322. http://dx.doi.org/10.1021/acsnano.9b03475.
Moscariello, P.; Raabe, M.; Liu, W.; Bernhardt, S.; Qi, H.; Kaiser, U.; Wu, Y.; Weil, T.; Luhmann, H. J.; Hedrich, J. (2019) Unraveling In Vivo Brain Transport of Protein-Coated Fluorescent Nanodiamonds. Small 15, 42, 1902992. http://dx.doi.org/https://doi.org/10.1002/smll.201902992.
Lehnert, T.; Ghorbani-Asl, M.; Köster, J.; Lee, Z.; Krasheninnikov, A. V.; Kaiser, U. (2019) Electron-Beam-Driven Structure Evolution of Single-Layer MoTe2 for Quantum Devices. ACS Applied Nano Materials 2, 5, 3262-3270. http://dx.doi.org/10.1021/acsanm.9b00616.
Kohsakowski, S.; Pulisova, P.; Mitoraj, D.; Neubert, S.; Biskupek, J.; Kaiser, U.; Reichenberger, S.; Marzun, G.; Beranek, R. (2019) Electrostatically Directed Assembly of Nanostructured Composites for Enhanced Photocatalysis. Small Methods 3, 8, 1800390. http://dx.doi.org/https://doi.org/10.1002/smtd.201800390.
Kinyanjui, M. K.; Björkman, T.; Lehnert, T.; Köster, J.; Krasheninnikov, A.; Kaiser, U. (2019) Effects of electron beam generated lattice defects on the periodic lattice distortion structure in $1T\text{\ensuremath{-}}\mathrm{Ta}{\mathrm{S}}_{2}$ and $1T\text{\ensuremath{-}}\mathrm{TaS}{\mathrm{e}}_{2}$ thin layers. Physical Review B 99, 2, 024101. http://dx.doi.org/10.1103/PhysRevB.99.024101.
Kaiser, U. (2019) Imaging and Spectroscopy of Low-Dimensional Low-Z Materials by 20-300kV TEM. Microscopy and Microanalysis 25, S2, 1726-1727. http://dx.doi.org/10.1017/S143192761900936X.
Kabiri, Y.; Ravelli, R. B. G.; Lehnert, T.; Qi, H.; Katan, A. J.; Roest, N.; Kaiser, U.; Dekker, C.; Peters, P. J.; Zandbergen, H. (2019) Visualization of unstained DNA nanostructures with advanced in-focus phase contrast TEM techniques. Scientific Reports 9, 1, 7218. http://dx.doi.org/10.1038/s41598-019-43687-5.
Jordan, J. W.; Lowe, G. A.; McSweeney, R. L.; Stoppiello, C. T.; Lodge, R. W.; Skowron, S. T.; Biskupek, J.; Rance, G. A.; Kaiser, U.; Walsh, D. A.; Newton, G. N.; Khlobystov, A. N. (2019) Host–Guest Hybrid Redox Materials Self-Assembled from Polyoxometalates and Single-Walled Carbon Nanotubes. Advanced Materials 31, 41, 1904182. http://dx.doi.org/https://doi.org/10.1002/adma.201904182.
Ji, Y.; Ma, Y.; Liu, R.; Ma, Y.; Cao, K.; Kaiser, U.; Varzi, A.; Song, Y.-F.; Passerini, S.; Streb, C. (2019) Modular development of metal oxide/carbon composites for electrochemical energy conversion and storage. Journal of Materials Chemistry A 7, 21, 13096-13102. http://dx.doi.org/10.1039/C9TA03498F.
George, A.; Neumann, C.; Kaiser, D.; Mupparapu, R.; Lehnert, T.; Hübner, U.; Tang, Z.; Winter, A.; Kaiser, U.; Staude, I.; Turchanin, A. (2019) Controlled growth of transition metal dichalcogenide monolayers using Knudsen-type effusion cells for the precursors. Journal of Physics: Materials 2, 1, 016001. http://dx.doi.org/10.1088/2515-7639/aaf982.
Feicht, P.; Biskupek, J.; Gorelik, T. E.; Renner, J.; Halbig, C. E.; Maranska, M.; Puchtler, F.; Kaiser, U.; Eigler, S. (2019) Brodie's or Hummers’ Method: Oxidation Conditions Determine the Structure of Graphene Oxide. Chemistry – A European Journal 25, 38, 8955-8959. http://dx.doi.org/https://doi.org/10.1002/chem.201901499.
Cambaz, M. A.; Vinayan, B. P.; Pervez, S. A.; Johnsen, R. E.; Geßwein, H.; Guda, A. A.; Rusalev, Y. V.; Kinyanjui, M. K.; Kaiser, U.; Fichtner, M. (2019) Suppressing Dissolution of Vanadium from Cation-Disordered Li2–xVO2F via a Concentrated Electrolyte Approach. Chemistry of Materials 31, 19, 7941-7950. http://dx.doi.org/10.1021/acs.chemmater.9b02074.
2018
Shi, L.; Yanagi, K.; Cao, K.; Kaiser, U.; Ayala, P.; Pichler, T. (2018) Extraction of Linear Carbon Chains Unravels the Role of the Carbon Nanotube Host. ACS Nano 12, 8, 8477-8484. http://dx.doi.org/10.1021/acsnano.8b04006.
Seiler, S.; Halbig, C. E.; Grote, F.; Rietsch, P.; Borrnert, F.; Kaiser, U.; Meyer, B.; Eigler, S. (2018) Effect of friction on oxidative graphite intercalation and high-quality graphene formation. Nat Commun 9, 1, 836. http://dx.doi.org/10.1038/s41467-018-03211-1.
Kühne, M.; Börrnert, F.; Fecher, S.; Ghorbani-Asl, M.; Biskupek, J.; Samuelis, D.; Krasheninnikov, A. V.; Kaiser, U.; Smet, J. H. (2018) Reversible superdense ordering of lithium between two graphene sheets. Nature 564, 7735, 234-239.
Cao, K.; Zoberbier, T.; Biskupek, J.; Botos, A.; McSweeney, R. L.; Kurtoglu, A.; Stoppiello, C. T.; Markevich, A. V.; Besley, E.; Chamberlain, T. W.; Kaiser, U.; Khlobystov, A. N. (2018) Comparison of atomic scale dynamics for the middle and late transition metal nanocatalysts. Nat Commun 9, 1, 3382. http://dx.doi.org/10.1038/s41467-018-05831-z.
Cao, K.; Chamberlain, T. W.; Biskupek, J.; Zoberbier, T.; Kaiser, U.; Khlobystov, A. N. (2018) Direct Correlation of Carbon Nanotube Nucleation and Growth with the Atomic Structure of Rhenium Nanocatalysts Stimulated and Imaged by the Electron Beam. Nano Lett 18, 10, 6334-6339. http://dx.doi.org/10.1021/acs.nanolett.8b02657.
Börrnert, F.; Renner, J.; Kaiser, U. (2018) Electron Source Brightness and Illumination Semi-Angle Distribution Measurement in a Transmission Electron Microscope. Microscopy and Microanalysis 24, 3, 249-255.
Börner, P. C.; Kinyanjui, M. K.; Björkman, T.; Lehnert, T.; Krasheninnikov, A. V.; Kaiser, U. (2018) Observation of charge density waves in free-standing 1T-TaSe2 monolayers by transmission electron microscopy. Applied Physics Letters 113, 17, 173103.
Stoppiello, C. T.; McSweeney, R. L.; Khlobystov, A. N.; Kaiser, U. Atomic mechanism of metal crystal nucleus formation in a single-walled carbon nanotube. Nature Chemistry 12.
