Graphene layer effect on protecting the refined surface of transition metal substrate Re(0 0 0 1): A first-principles study

Abstract

Density functional theory (DFT) calculations have been carried out to investigate the graphene layer effect (single layer, bilayer, and three layers) on protecting the strongly interacting Re(0 0 0 1) surface. The calculation results indicate that single layer graphene on Re(0 0 0 1) owns large geometrical corrugation and enhanced surface chemical activity, which is attributed to the covalent interfacial interaction between the graphene and Re(0 0 0 1). However, with the increasing of graphene layers, the geometrical corrugation, surface chemical activity, and surface forces (adhesion and friction) are all reduced remarkably, especially a single layer graphene is enough to screen the influence from Re(0 0 0 1). Thus, increasing graphene layer properly could achieve better performances of protecting the active surface of transition metal substrate from chemical modification, friction, and wear.