The adsorption and reaction of vinyl acetate on Au/Pd(100) alloy surfaces

Journal Article · Sun Jan 01 00:00:00 EST 2012 · Surface Science

DOI:https://doi.org/10.1016/j.susc.2012.03.011· OSTI ID:1078215

Li, Zhenjun ^[1]; Calaza, Florencia C ^[2]; Tysoe, Wilfred ^[3]

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1. Pacific Northwest National Laboratory (PNNL)
2. ORNL
3. University of Wisconsin, Milwaukee

The surface chemistry of vinyl acetate monomer (VAM) is studied on Au/Pd(100) alloys as a function of alloy composition using temperature-programmed desorption and reflection adsorption infrared spectroscopy. VAM adsorbs weakly on isolated palladium sites on the alloy with a heat of adsorption of ~55 kJ/mol, with the plane of the VAM adsorbed close to parallel to the surface. The majority of the VAM adsorbed on isolated sites desorbs molecularly with only a small portion decomposing. At lower gold coverages (below ~0.5 ML of gold), where palladium palladium bridge sites are present, VAM binds to the surface in a distorted geometry via a rehybridized vinyl group. A larger proportion of this VAM decomposes and this reaction is initiated by C\O bond scission in the VAM to form adsorbed acetate and vinyl species. The implication of this surface chemistry for VAM synthesis on Au/Pd(100) alloys is discussed.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1078215
• Journal Information: Surface Science, Vol. 606, Issue 13-14; ISSN 0039-6028
• Country of Publication: United States
• Language: English