Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5424933 | Surface Science | 2007 | 8 Pages |
The adsorption and reaction of hydrogen sulfide, H2S, have been studied on cerium oxide thin films that were vapor deposited on Ru(0Â 0Â 0Â 1). The behavior of the H2S was examined as a function of Ce oxidation state. H2S weakly chemisorbs on fully oxidized CeO2 desorbing near 155Â K. Hydrogen from the H2S reacts with the surface O to desorb as water between 200Â K and 450Â K. When ca. 20% of the Ce4+ is reduced to Ce3+ more H2S dissociates to -OH and -SH and water is produced near 580Â K. When the ceria is ca. 70% reduced, water formation is suppressed and H2 desorbs near 580Â K. S 2p photoelectron spectroscopy indicates the decomposition of H2S into -SH and then -S as the sample is annealed from 100Â K to 600Â K. O 1s photoemission indicated the presence of H2O and -OH.