Roles of oxyanions in promoting the partial oxidation of styrene on Ag(110): nitrate, carbonate, sulfite, and sulfate.
The promotion roles of nitrate, carbonate, sulfite, and sulfate in oxidation of styrene on Ag(110) have been studied by means of temperature-programmed reaction spectroscopy (TPRS) and X-ray photoelectron spectroscopy (XPS). While isolated nitrate leads only to the secondary oxidation of styrene, a surface co-covered by nitrate, oxygen, and 0.1 ML cesium promotes a low-temperature epoxidation pathway. XPS indicates that adsorbed surface oxygen is the oxidant in this selective reaction pathway, and, though it affects the reactivity of the surface oxygen, nitrate is a spectator. Carbonate acts as an oxygen transfer agent and exhibits similar reactivity and selectivity as an oxidant for styrene as does atomic oxygen on Ag(110). The reactivities of sulfite and sulfate are strongly dependent on their surface structures, the c(6 × 2) sulfite showing the capacity to transfer oxygen to styrene.
School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
Ling
L
Zhou
Robert J
RJ
Madix
D000327:Adsorption; D000838:Anions / Q000737:chemistry; D002254:Carbonates / Q000737:chemistry*; D009566:Nitrates / Q000737:chemistry*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D010316:Particle Size; D012834:Silver / Q000737:chemistry*; D020058:Styrene / Q000737:chemistry*; D013431:Sulfates / Q000737:chemistry*; D013447:Sulfites / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature
D000838:Anions; D002254:Carbonates; D009566:Nitrates; D013431:Sulfates; D013447:Sulfites; D012834:Silver; D020058:Styrene; D010100:Oxygen