Dependency of sliding friction for two-dimensional systems on electronegativity

We study the role of electronegativity in sliding friction for five different two-dimensional (2D) monolayer systems using ab initio calculations within density functional theory with van der Waals corrections. show that depends strongly on involved atoms' difference. All studied exhibit almost same magnitude force when along nonpolar path, independent material and surface structures. In contrast, a polar obeys universal linear scaling law where is proportional to difference its constituent atoms. atomic dipoles 2D monolayers, induced by difference, enhance corrugation charge distribution increase barriers accordingly. Our studies reveal plays an important low-dimensional systems, provides strategy designing nanoscale devices.