Abstract
Using molecular dynamics (MD) simulations, we have investigated the kinetics of the graphene edge folding process. The lower limit of the energy barrier is found to be ∼380 meV/Å (or about 800 meV per edge atom) and ∼50 meV/Å (or about 120 meV per edge atom) for folding the edges of intrinsic clean single-layer graphene (SLG) and double-layer graphene (DLG), respectively. However, the edge folding barriers can be substantially reduced by imbalanced chemical adsorption, such as of H atoms, on the two sides of graphene along the edges. Our studies indicate that thermal folding is not feasible at room temperature (RT) for clean SLG and DLG edges and is feasible at high temperature only for DLG edges, whereas chemical folding (with adsorbates) of both SLG and DLG edges can be spontaneous at RT. These findings suggest that the folded edge structures of suspended graphene observed in some experiments are possibly due to the presence of adsorbates at the edges.
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Yan, Q.; Huang, B.; Yu, J.; Zheng, F.; Zang, J.; Wu, J.; Gu, B.; Liu, F.; Duan, W. Intrinsic current-voltage characteristics of graphene nanoribbon transistors and effect of edge doping. Nano Lett. 2007, 7, 1469–1473.
Fasolino, A.; Los, J. H.; Katsnelson, M. I. Intrinsic ripples in graphene. Nat. Mater. 2007, 6, 858–861.
Huang, B.; Liu, F.; Wu, J.; Gu, B.; Duan, W. Suppression of spin polarization in graphene nanoribbons by edge defects and impurities. Phys. Rev. B 2008, 77, 153411.
Shenoy, V. B.; Reddy, C. D.; Ramasubramaniam, A.; Zhang, Y. W. Edge-stress-induced warping of graphene sheets and nanoribbons. Phys. Rev. Lett. 2008, 101, 245501.
Bets, K. V.; Yokobson, B. I. Spontaneous twist and intrinsic instabilities of pristine graphene nanoribbons. Nano Res. 2009, 2, 161–166.
Huang, B.; Liu, M.; Su, N.; Wu, J.; Duan, W.; Gu, B.; Liu, F. Quantum manifestations of graphene edge stress and edge instability: A first-principles study. Phys. Rev. Lett. 2009, 102, 166404.
Meyer, J. C.; Geim, A. K.; Katsnelson, M. I.; Novoselov, K. S.; Booth, T. J.; Roth, S. The structure of suspended graphene sheets. Nature 2007, 446, 60–63.
Gass, M. H.; Bangert, U.; Bleloch, A. L.; Wang, P.; Nair, R. R. Free-standing graphene at atomic resolution. Nat. Nanotechnol. 2008, 3, 676–681.
Liu, Z.; Suenage, K.; Harris, P. J. F.; Iijima, S. Open and closed edges of graphene layers. Phys. Rev. Lett. 2009, 102, 015501.
Huang, J. Y.; Ding, F.; Yakobson, B. I.; Lu, P.; Qi, L.; Li, J. In situ observation of graphene sublimation and multi-layer edge reconstructions. P. Natl. Acad. Sci. U.S.A. 2009, 106, 10103–10108.
Yu, W. J.; Chae, S. H.; Perello, D.; Lee, S. Y.; Han, G. H.; Yun, M.; Lee, Y. H. Synthesis of edge-closed graphene ribbons with enhanced conductivity. ACS Nano 2010, 4, 5480–5486.
Cranford, S.; Sen, D.; Buehler, M. J. Meso-origami: Folding multilayer graphene sheets. Appl. Phys. Lett. 2009, 95, 123121.
Cruz-Silva, E.; Botello-Méndez, A. R.; Barnett, Z. M.; Jia, X.; Dresselhaus, M. S.; Terrones, H.; Terrones, M.; Sumpter, B. G.; Meunier, V. Controlling edge morphology in graphene layers using electron irradiation: From sharp atomic edges to coalesced layers forming loops. Phys. Rev. Lett. 2010, 105, 045501.
Yu, D.; Liu, F. Synthesis of carbon nanotubes by rolling up patterned graphene nanoribbons using selective atomic adsorption. Nano Lett. 2007, 7, 3046–3050.
Brenner, D. W.; Shenderova, O. A.; Harrison, J. A.; Stuart, S. J.; Ni, B.; Sinnott, S. B. A second-generation reactive empirical bond order (REBO) potential energy expression for hydrocarbons. J. Phys.-Condens. Mat. 2002, 14, 783–802.
Girifalco, L. A.; Lad, R. A. Energy of cohesion, compressibility, and the potential energy functions of the graphite system. J. Chem. Phys. 1956, 25, 693–697.
Zecho, T.; Guttler, A.; Sha, X. W.; Jackson, B.; Kuppers, J. Adsorption of hydrogen and deuterium atoms on the (0001) graphite surface. J. Chem. Phys. 2002, 117, 8486–8492.
Xie, X.; Ju, L.; Feng, X.; Sun, Y.; Zhou, R.; Liu, K.; Fan, S.; Li, Q.; Jiang, K. Controlled fabrication of high-quality carbon nanoscrolls from monolayer graphene. Nano Lett. 2009, 9, 2565–2570.
Sidorov, A.; Mudd, D.; Sumanasekera, G.; Ouseph, P. J.; Jayanthi, C. S.; Wu, S. Y. Electrostatic deposition of graphene in a gaseous environment: A deterministic route for synthe-sizing rolled graphenes. Nanotechnology 2009, 20, 055611.
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Su, N., Liu, M. & Liu, F. Chemical versus thermal folding of graphene edges. Nano Res. 4, 1242–1247 (2011). https://doi.org/10.1007/s12274-011-0175-0
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DOI: https://doi.org/10.1007/s12274-011-0175-0