Electronic Insights Into the Intrinsic Origin of Interfacial Friction

Abstract

Here we provide atomistic insights into the intrinsic origin of friction from interfacial charge fluctuation by density functional theory (DFT) calculations of typical 2D vdWs systems, including graphene, h-BN and transition metal chalcogenides. We proposed a quantitative method to discriminate the redistribution of interfacial charge density in the sliding process. It is thus discovered that the synchronous evolution between sliding charge fluctuation and potential energy surfaces corrugation is necessary to surmount frictional resistance, giving a linear relation coefficient k for charge transfer and potential energy acting on the frictional sliding under different normal stress. This study implies that the inherent friction characteristic of the sliding systems could be traced back to the evolution of charge transfer, enabling prediction and design of tribological response.