DFT study on the adsorption and dissociation of H2S on CuO(111) surface

Abstract

Density functional theory (DFT) together with periodic slab models is employed to investigate the adsorption and dissociation of H₂S on the CuO(111) surface. The structures of H₂S, SH, S atom, and H atom on the CuO(111) surface, as well as the co-adsorption of SH and a H atom, and the co-adsorption of S atom and two H atoms, have been determined. The pathways of the dissociation of H₂S on the CuO(111) surface are constructed. The activation energy and reaction energy of each step in different pathways are also calculated. The energy barrier of the first dehydrogenation process in the pathway 2 is 0.60 kJ mol⁻¹ higher than that in the pathway 1, but the energy barrier of the second dehydrogenation process in the pathway 2 is 23.50 kJ mol⁻¹ lower than that in the pathway 1, implying that the structure with two H atoms adsorbed on the O_suf sites is the most probable product for the dissociation of H₂S on the CuO(111) surface.