Coverage and geometry effects on work function of cathode surface with adsorbed atoms based on ab initio calculations

Work function is one of the most fundamental electronic properties of a metallic surface. The calculations of work function in our work were performed using density-functional-theory (DFT) in the local density approximation, with a plane wave basis set and the projector-augmented wave method, as implemented in the Vienna ab-initio simulation package. Using DFT calculations, we investigated the work function of the tungsten substrate could be lowered obviously due to the adsorbed variant coverage and geometry of atoms on the tungsten (001) surface.