Influence of vacancies on the elastic properties of a graphene sheet

The influence of vacancies on the elastic properties of a single-layer graphene sheet is investigated using atomistic finite element analysis. The location and density of vacancies (vacancy number per unit area of graphene sheet) are the main parameters investigated. It is found that a single vacancy yields only a minor reduction on the effective elastic modulus of the graphene sheet, irrespective of its position in the sheet, but this elastic parameter is significantly reduced as the number of vacancies increases. The position of the vacancy significantly influences the shear modulus and Poisson's ratio of the sheet. The reduction in shear modulus and Poisson's ratio is more pronounced when the vacancy is in a region of large strain gradients. (C) 2011 Published by Elsevier B.V.