CO oxidation reaction on Au clusters supported on the TiO$_{2}$(110) surface

We have studied by means of density functional theory (DFT) plane waves calculations, the CO oxidation reaction on Au$_{8}$ clusters adsorbed on both the stoichiometric and reduced rutile TiO$_{2}$(110) surfaces. O$_{2}$ molecules bind at the interface between the TiO$_{2}$(110) surface and the gold particle, where they become partially charged through the population of the anti-bonding molecular orbital, resulting in the extension of the O-O bond length to values of peroxo-like states. When CO is co-adsorbed on the gold-particles, the Langmuir-Hinshelwood and the Elay-Rideal mechanisms are possible for the oxidation reaction. Both the catalytic cycles have been considered and the theoretical results have been compared with experimental findings obtained on size-selected Au$_{8}$ clusters deposited on thin, oxidized and reduced TiO$_{2}$ films.