Abstract
A comprehensive, coverage-dependent mean-field microkinetic model is developed for the hydrogenation of carbonyl compounds on Cu(111). In the model, hydrogenation by surface hydrogen, surface hydroxyl species, and adsorbed water molecules is considered, including a reaction pathway via keto–enol tautomerization. The model parameters were calculated by VdW-DF2 density functional theory and account for inter- and intraspecies repulsion. Accounting for these coverage effects changes the surface from being completely covered with 25% oxygen atoms and 75% hydroxyl groups to a surface with 65% free sites. Including coverage effects also surprisingly increases the calculated turnover frequency from 6 × 10–5 to 2 × 10–3 s–1. In the dominant reaction path, the carbonyl group is hydrogenated to an alkoxy intermediate by surface hydrogen, followed by a proton transfer from either a surface hydroxyl species or an adsorbed water molecule to form the alcohol product. The addition of small amounts of water suffices to o...
Published Version
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