Computational investigation of the temperature influence on the cleavage of a graphite surface

SURFACE SCIENCE

卷:604

Article

Prodanov, N. V.¹  Khomenko, A. V.¹ 

[1] Sumy State Univ, UA-40007 Sumy, Ukraine

关键词: Adhesion;    Graphite;    Exfoliation;    Graphene;    Molecular dynamics;   

DOI  :  10.1016/j.susc.2010.01.024

来源: Elsevier

【 摘 要 】

Mechanical exfoliation exfoliation of a graphite surface with an adhesive nanoasperity is studied under different temperatures ranging from 298 K to 2 K using classical molecular dynamics. Two types of the interlayer interaction are investigated. For a pairwise Lennard-Jones potential the complete removal of the upper graphene layer during the retraction of the nanoasperity occurs in the whole range of the temperatures considered. The results obtained using registry dependent potential, which takes into account electronic delocalization contribution besides the van der Waals one, exhibit more pronounced temperature dependence. In this case the exfoliation takes place for temperatures higher than 16 K, but beginning from 8 K down to 2 K the system behavior manifests qualitative changes with the absence of cleavage of the sample. Analytical estimates combined with the results of the simulations reveal that the contribution of the overlap of it orbitals of carbon atoms plays an important role in the exfoliation of graphite. (C) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

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