Tensile properties of graphene nanotube hybrid structures : a molecular dynamics study

Graphene has been reported with record-breaking properties which have opened up huge potential applications. A considerable research has been devoted to manipulate or modify the properties of graphene to target a more smart nanoscale device. Graphene and carbon nanotube hybrid structure (GNHS) is one of the promising graphene derivative, whose mechanical properties have been rarely discussed in literature. Therefore, the mechanical properties of GNHS is studied in this paper based on the large-scale molecular dynamics simulation. The target GNHS is constructed by considering two separate graphene layers that are being connected by single-wall carbon nanotubes (SWCNTs) according to the experimental observations. It is found that the GNHSs exhibit much lower yield strength, Young's modulus, and earlier yielding compared to bilayer graphene sheet. Fracture of GNHSs is found to initiate at the connecting region between carbon nanotubes (CNTs) and graphene. After failure, monatomic chains are normally observed at the front of the failure region, and the two graphene layers at the failure region without connecting CNTs will adhere to each other, generating a bilayer graphene sheet scheme (with a layer distance about 3.4 A). This study will enrich the current understanding of the mechanical performance of GNHS, which will guide the design of GNHS and shed light on its various applications.