First-principles study of the work function of nitrogen doped molybdenum (110) surface.

The electronic properties of nitrogen doped Mo(110) surfaces were investigated using the first-principles pseudopotential method within the local density approximation in order to determine the effect of doping on the work function. Nitrogen doping was modeled by adsorbing N in both surface and subsurface positions. Surface adsorption of nitrogen was found to increase the work function by as much as 2 eV due to the negative surface dipole induced by the electronegativity of nitrogen. Subsurface doping of nitrogen is energetically similar to surface adsorption, but has a small effect on the work function and only when within the first two to three surface Mo layers. [ABSTRACT FROM AUTHOR]