▎ 摘　　要

In this paper, classical molecular dynamics simulations are conducted to study the fabrication of nanopore in graphene under electron and ion beam irradiation, in which the emphasis is put on the influence of substrate and graphene layers. Firstly, nanopore structures are confirmed to be generated on suspended and supported graphene with suitable incident parameters, while the existing of substrate will induce different phenomena and bring distinguishing results. Then different mechanisms are put forward to explain these distinct phenomena for suspended and supported case. In addition, the optimal parameters for the generation of a high quality nanopore in suspended and supported graphene are derived and the influence of graphene layers is discussed. Specially, the formation of cross-linkings between different layers is examined. Lastly, the influences of the inherent vacancies and sputtered atoms induced vacancies on the mechanical properties of nanoporous graphene are researched by tensile test simulations. These results can help us open the possibilities for better control of nanopore devices. (C) 2015 Elsevier B.V. All rights reserved.