Preservation of the frictional properties of h-BN under chemical modification in the presence of a commensurate Ni(1 1 1) substrate

Abstract

By means of density functional theory (DFT) calculations, we investigate the fluorination and hydrogenation activities of h-BN layer and the surface frictional properties of fluorinated h-BN on commensurate Ni(1 1 1) substrate. The calculation results indicate that Ni(1 1 1) influences the chemical activity of h-BN and the F atoms and H atoms prefer to adsorb on the B atoms and N atoms, respectively. The fluorination activity on B atoms is largely enhanced, while the hydrogenation on h-BN layer is much difficult. Meanwhile commensurate Ni(1 1 1) confines the topography corrugation caused by fluorination and the frictional properties of flattened fluorinated h-BN on Ni(1 1 1) are investigated. It is found that the flattened surface of fluorinated h-BN maintains the potential energy corrugation when sliding against a single h-BN layer, and the sliding potential energy corrugation decreases remarkably for the paired fluorinated surfaces. Variations of binding energy and friction at the interface after chemical modification are understood by interfacial charge redistribution. This study indicates the low friction of h-BN can be preserved in the presence of a commensurate Ni(1 1 1) substrate under chemical modification environment.