Mechanism of selective alcohol oxidation to aldehydes on gold catalysts: Influence of surface roughness on reactivity

The complete reaction pathway for the selective alcohol oxidation to aldehyde has been obtained from periodic density functional theory (DFT) calculations on a series of catalyst models having Au atoms with different coordination number. A clear trend exists in the reactivity of the surfaces: it increases with decreasing the Au coordination number, suggesting that a distribution of Au sites with different activity might exist on the surface of real catalysts. This hypothesis emerging from the theoretical study has been experimentally confirmed by measuring the kinetics of benzyl alcohol oxidation on a series of Au/MgO catalysts having different particle diameter and therefore different concentration and distribution of low coordinated Au sites.

A complete DFT study of the mechanism of selective alcohol oxidation on a series of Au catalyst models suggests that the activity of Au sites inversely correlates with their coordination number. This hypothesis is experimentally confirmed by a kinetic study of benzyl alcohol oxidation on a series of Au/MgO catalyst differing in Au particle diameter and therefore in concentration and distribution of low coordinated Au sites..Figure optionsDownload high-quality image (79 K)Download as PowerPoint slideResearch highlights
► DFT study of the mechanism of Au-catalyzed selective alcohol oxidation.
► Reactivity of Au surfaces inversely correlates with coordination number of Au sites.
► Kinetics of benzyl alcohol oxidation confirm heterogeneity of sites in Au surfaces.