Negative Poisson's ratio in graphene-based carbon foams

摘要: Using molecular dynamics simulations, we find an in-plane negative Poisson's ratio intrinsically existing in the graphene-based three-dimensional (3D) carbon foams (CFs) when they are compressed uniaxially. Our study shows that present CFs is attributed to their unique structures and triggered by buckling of CF structures. This novel mechanism makes strongly depend on cell length, which offers us efficient means tune nanomaterials. Moreover, as modes topographically different directions, found be anisotropic, contrast isotropic positive observed prior buckling. The discovery intrinsic 3D will significantly expand family auxetic Meanwhile, nano-auxetics proposed here may open a door manufacture new materials at nanoscale.