Adsorption behavior of (CH₃)₂S on sputtered and annealed Rh(100) surface by AFM, XPS and NEXAFS

Abstract

The temperature dependent reaction of dimethyl sulfide (CH₃)₂S : DMS on Rh(100) over the temperature range of 90-300 K and the surface reaction of DMS depending on the morphology of Rh(100) surface have been studied with Atomic Force Microscopy (AFM), X-ray Photoelectron Spectroscopy (XPS) and Sulfur K-edge Near Edge X-ray Absorption Fine Structure (NEXAFS) techniques. DMS molecules adsorb molecularly on 850 K annealed Rh(100) surface at 90 K, and some of DMS are dissociated into methanethiolate CH₃S- : MT or atomic sulfur as the temperature of the substrate increases. The temperature dependent reduction of the total coverage of sulfur indicates that some of sulfur-containing molecules desorb from the surface. On the other hand, it is found that DMS decomposes into atomic S on 1000 K annealed Rh(100) surface at 90 K. These results indicate that the dissociative reaction of DMS/Rh(100) is more sensitive to the surface morphology than that of Cu(100). [DOI: 10.1380/ejssnt.2006.39]