▎ 摘　　要

We report results of a systematic computational study on the mechanical response of graphene nanomeshes (GNMs) to uniaxial tensile straining based on molecular-dynamics simulations of dynamic deformation tests according to a reliable bond-order interatomic potential. We examine the effects on the GNM mechanical behavior under straining along different directions of the nanomesh pore morphology and pore edge passivation by testing GNMs with elliptical pores of various aspect ratios and different extents of edge passivation through termination with H atoms of under-coordinated edge C atoms. We establish the dependences of the ultimate tensile strength, fracture strain, and toughness of the GNMs on the nanomesh porosity, derive scaling laws for GNM strength-density relations, and find the GNMs' mechanical response to uniaxial straining to be anisotropic for pore morphologies deviating from circular pores. We also find that the GNM tensile strength decays exponentially with increasing GNM porosity and that pore edge termination with H atoms causes a reduction in the GNMs' elastic stiffening, strength, deformability, and toughness; this hydrogen embrittlement effect is more pronounced at a high level of pore edge passivation that renders the edge C atoms sp(3)-hybridized. The underlying mechanisms of crack initiation and propagation and nanomesh failure for the various types of GNMs examined also are characterized in atomistic detail. Overall, even highly porous GNMs remain particularly strong and deformable and, therefore, constitute very promising 2D mechanical metamaterials. Published under license by AIP Publishing.