From flat graphene to bulk carbon nanostructures

Studies on thin sheets and related materials are of high importance nowadays because of their great potential in various applications. The latest success in the production of graphene opens many new opportunities for the construction of novel three-dimensional carbon nanostructures that exhibit good mechanical and electronic properties together with high specific surface area. Such novel nanostructures based on graphene sheets are very promising for energy storage devices, supercapacitors and stretchable electronics, to name a few. In this work, the mechanical responses of new bulk carbon nanostructures under hydrostatic pressure or shear strain are investigated, respectively, via molecular dynamics simulations. The size effect of the structural units on the strength of crumpled graphene is analyzed. The studied bulk carbon nanostructures are found to be extremely stable against diamondization. It is shown that the structures and mechanical properties of bulk carbon nanomaterials can be altered by severe plastic shear deformation. Shear strain leads to the formation of stable structures, even at relatively small strain.