Theoretical study of hydrogen adsorption and diffusion on TiN(100) surface

TiN bulk and surface energy and hydrogen atom adsorption at three different sites have been studied using density functional theory (DFT) with local and non-local exchange-correlation functionals. Calculations of surface energies confirm the experimental findings that the (100) surface has the lowest and the (111) surface the highest surface energy, respectively. Adsorption of H on top of Ti atom is more favorable by 1.7 kcal/mol than on top of N atom and is in agreement with plane-wave calculations and experimental results available in the literature. We also discuss the surface diffusion scenario of H on the (100) surface of TiN.