Tuning the electronic structure of hexagonal boron nitride by carbon atom modification: a feasible strategy to reduce sliding friction

Abstract

Essentially, the interlayer interaction of the two-dimensional (2D) layered material is the overlap of electron clouds outside the nucleus atomically. When the layered material slides between layers, the contribution of electrons to the interlayer interaction is dominant, so it is expected to modify the electronic configuration of the system to change the interlayer interaction for the purpose of reducing interlayer sliding friction. In this paper, using density functional theory (DFT) calculation, we report an effective method to reduce the sliding friction between the two-layer hexagonal boron nitride layers for changing the hexagonal boron nitride electronic structure via introducing carbon. Research results indicate that the increase of the potential energy fluctuation along the sliding path increases with the increase of the load, which is caused by the difference of the degree of interlayer interaction on the sliding path with the increase of the load; at the same time, we found that the appearance of C at the B or N position can promote the interlayer charge transfer to different extents (B position is better than N position) in the BN/BN bilayer, and then produce the effect of reducing the energy barrier on the sliding path between the layers.