TPD study of the reaction of CH\u3csub\u3e3\u3c/sub\u3eCH\u3csub\u3e2\u3c/sub\u3eSH and (CH\u3csub\u3e3\u3c/sub\u3eCH\u3csub\u3e2\u3c/sub\u3e)\u3csub\u3e2\u3c/sub\u3eS\u3csub\u3e2\u3c/sub\u3e on ZnO(0001) and ZnO

摘要

Temperature programmed desorption (TPD) was used to study the reaction of CH3CH2SH and (CH3CH2)2S2 on the (0001) and surface of ZnO. The interaction of these molecules with ZnO was found to be structure-sensitive. Both the thiol and disulfide adsorbed dissociatively on ZnO(0001) forming adsorbed ethylthiolate intermediates, while only molecularly on ZnO. This result indicates that exposed cation-anion site pairs and exposed cations are the active sites for dissociative adsorption of CH3CH2SH and (CH3CH2)2S2, respectively. Decomposition to produce ethylene and adsorbed sulfur atoms was the only reaction pathway observed for adsorbed ethylthiolates on the (0001) surface. This is in contrast to adsorbed methylthiolates which undergo coupling to produce dimethylsulfide and oxydesulfurization to produce aldehydes and adsorbed carboxylates.