Low-Temperature Catalytic H2 Oxidation over Au Nanoparticle/TiO2Dual Perimeter Sites

摘要

The catalytic oxidation of H2 is of great interest due to its role in H2O2 synthesis, catalytic oxidation of hydrocarbons, and the selective removal of CO from hydrogen streams as well as for its simplicity which makes it ideal for fundamental bond making and breaking studies. This is especially true for supported Au nanoparticles which were found to show unusually high activity by Haruta et al. Previous explanations for this activity have invoked quantum size effects for Au particles in the 2 nm range, electronic effects in thin films of Au, and enhancement of the fraction of perimeter sites. Recent experiments on inverse TiO2/Au catalysts have suggested that the enhanced catalytic activity may be due to active sites at the TiO2/Au interface rather than a quantum size effect.