Mechanical properties of a G/h-BN heterobilayer nanosheets coupled by interlayer sp³ bonds and defects

Abstract

Abstract The mechanical properties of graphene/hexagonal boron nitride (G/h-BN) heterobilayer nanosheets coupled by interlayer sp 3 bonds and defects have been investigated by using the molecular dynamics (MD) simulation. For this purpose, interlayer sp 3 bonds and two kinds of geometric imperfection (including rhombus and square nanopore) are formed in the G/h-BN heterobilayer nanosheets. The effects of adding the nanopore diameter, interlayer sp 3 bonds fraction, and the influence of different position of geometric imperfection in heterobilayer nanostructure on mechanical properties have been investigated. The result shows that when sp 3 bonds and nanopore coexist, the mechanical properties of defective graphene layer are higher than that of defective hexagonal boron nitride (h-BN) layer. Meanwhile, the negative effect of rhomboid nanohole on mechanical properties of heterostructure is weaker than that of square nanohole. It is observed that that interlayer sp 3 bonds have greatest influence on the fracture strain of G/h-BN heterobilayer nanostructure, followed by fracture stress, and finally Young’s modulus. Another important point is that interlayer sp 3 bonds can be regarded as a special defect, and its value seems to outweigh the intrinsic defects.