Acetate coverage effect on the reactivity of vinyl acetate synthesis on Pd/Au alloy surfaces

作者：Xing Bin; Wei Zizhang; Wang Guichang^*

来源：Journal of Energy Chemistry, 2013, 22(4): 671-679.

DOI：10.1016/s2095-4956(13)60089-3

• VA synthesis
• Pd/Au(100)
• Pd/Au(111)
• acetate coverage effect
• reaction mechanism
• DFT calculations

Vinyl acetate (VA) synthesis on Pd/Au(111) and Pd/Au(100) surfaces has been systematically investigated through first-principles density functional theory (DFT) calculations. The DFT results showed that for VA synthesis, the 'Samanos' reaction mechanism (i.e., direct coupling of coadsorbed ethylene and acetate species and subsequent beta-hydride elimination to form VA) is more favorable than the 'Moiseev' mechanism (i.e., ethylene first dehydrogenates to form vinyl species which then couple with the coadsorbed acetate species to form VA). More importantly, it was found the surface coverage of acetate has a significant effect on the reactivity of VA synthesis, and the activation energy of the rate-controlling step on Pd/Au(100) surface is smaller than that on Pd/Au(111) surface (0.88 vs. 0.95 eV), indicating the former is more active than the latter.

• 出版日期2013-7
• 单位南开大学