(428d) Selective Oxidation Over Supported Au Catalysts

The unique catalytic activity of supported nanometer Au catalysts for the selective oxidation has captured the fascination of many researchers in heterogeneous catalysis as well as electrocatalysis.  While much is known about the unique properties of Au and the support that catalyze these reactions, the position and charge state of the active sites are still actively debated in the literature. Selective oxidation reactions over Au supported on TiO₂ for example has been of considerable interests for the partial oxidation as well as the electrocatalytic oxidation of CO as well as the catalytic and electrocatalytic oxidation of alcohols. The size of the  supported Au-particles  (nm vs. bulk), the presence of water, the pH of the media (acid vs. base), and the properties of the metal/support interface have all been shown to important.  Herein we describe the results of collaborative theoretical and experimental efforts that probe the nature of the active sites and the effects of the Au/TiO₂ support, the influence of water, pH and electrochemical potential on the catalytic and electrocatalytic oxidation of CO. We discuss the synergies between heterogeneous catalysis and electrocatalysis and also highlight the important differences between the two.  The ideas and concepts are also extended to other catalytic systems including that of the  water-gas shift reaction.