Size-dependent mechanical properties of twin graphene

Twin Graphene, a novel 2D planar semiconducting carbon allotrope predicted recently, has attracted tremendous attention due to its potential applications in nano electromechanical systems (NEMS). In this paper, we use Molecular Dynamics simulations to investigate the mechanical properties of twin graphene. By performing uniaxial tensile loading, we find that the Young’s modulus, failure stress and fracture strain of a twin graphene sheet are strongly dependent on its size. Rectangular sheets show more apparent anisotropy of mechanical properties than square sheets. Our results also demonstrate that the fracture pattern of twin graphene is dependent on its geometry, as a result of its diverse bond types and orientations. These findings present an in-depth understanding of size dependent mechanical properties of twin graphene, and may benefit its future applications as building blocks of NEMS devices.