• 文献标题:   Point defect weakened thermal contraction in monolayer graphene
  • 文献类型:   Article
  • 作  者:   ZHA XH, ZHANG RQ, LIN ZJ
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF CHEMICAL PHYSICS
  • ISSN:   0021-9606 EI 1089-7690
  • 通讯作者地址:   City Univ Hong Kong
  • 被引频次:   9
  • DOI:   10.1063/1.4892419
  • 出版年:   2014

▎ 摘  要

We investigate the thermal expansion behaviors of monolayer graphene and three configurations of graphene with point defects, namely the replacement of one carbon atom with a boron or nitrogen atom, or of two neighboring carbon atoms by boron-nitrogen atoms, based on calculations using first-principles density functional theory. It is found that the thermal contraction of monolayer graphene is significantly decreased by point defects. Moreover, the corresponding temperature for negative linear thermal expansion coefficient with the maximum absolute value is reduced. The cause is determined to be point defects that enhance the mechanical strength of graphene and then reduce the amplitude and phonon frequency of the out-of-plane acoustic vibration mode. Such defect weakening of graphene thermal contraction will be useful in nanotechnology to diminish the mismatching or strain between the graphene and its substrate. (C) 2014 AIP Publishing LLC.