The adsorption and dissociation of H2S on Cu(100) surface: A DTF study

Density functional theory was used to investigate the adsorption of H2S and H/HS, H/H/S on Cu(100). The pathways and transition states of H2S dissociation were also studied. Results show that H2S prefers the top site, while H, S and HS prefer the hollow site during the adsorption process. H2S, HS and S can chemisorb on Cu(100) through the SCu bond due to the hybridization of the s, p orbit of S and the d orbit of Cu. The order of the adsorption energy for three forms is as follows: H/H/S, H/HS and H2S. In addition, the dissociation of H2S molecule on Cu(100) is thought to be an exothermic process. The activation energy of the first and second SH bonds in H2S are low and similar (approximately 10.15 kcal/mol). In the dissociation of H2S, Cu atoms attract electrons from HS bond which leads the bond-breaking.