First principles studies of hydrogen sulfide adsorption and dissociation on NiAl(110)-(2x2)

Abstract

The molecular and dissociative adsorption of H2S molecule on NiAl(110) surface is examined using density functional theory (DFT). We have considered the five possible adsorption sites given in Fig.1. We have found that the binding geometry depicted in Fig. 2(e) was energetically more favorable than the others. For the dissociative adsorption of H2S molecule on NiAl(110) phase, it is found that SH molecule is attached almost Ni-Ni site while H atom is located to the surface 2Ni-Al site, with adsorption energy -1.23 eV. The atomic key parameters of considered systems have been compared with theoretical and experimental values (in the gas phase). We have also calculated the reaction path and energy profiles for dissociation of both H2S into SH-H and SH into S-H on NiAl(110) surface, and it is found that the both reaction is exothermic.