First-principles calculations combined with friction models to predict the moiré pattern effect on the interlayer friction of two-dimensional materials

Abstract

Moiré patterns formed by twisting and heterojunction formation have significant regulatory effects on frictional behavior, but no work has studied them through first-principles calculations combined with friction equations. In this paper, we studied the interlayer frictional properties of graphene/graphene (G/G) and graphene/hexagonal boron nitride (G/hBN) systems at different twist angles using first principles combined with the Prandtl-Tomlinson (PT), Frenkel-Kontorova (FK) and Frenkel-Kontorova-Tomlinson (FKT) models. The Moiré patterns formed by twisting and heterojunctions help to reduce the energy barrier of the system’s potential energy surface (PES), thereby reducing the friction force. The stick-slip processes of the friction system are related to the energy barrier, and the reduction in the energy barrier helps transition from stick-slip to continuous sliding. The calculation results of friction models are highly consistent with reported experimental results, showing that twisting and heterojunction formation significantly reduce frictional force. Among the three models, the PT model is better in describing superlubricity during incommensurate contact. This work deepens the understanding of Moiré pattern regulation of frictional behavior and proposes a new method using a friction model combined with first principles to study frictional phenomena.