The interaction of neutral and charged Au clusters with O2, CO and H2

Hybrid density functional calculations have been carried out for AuO2, AuCO, Au13, Au13O2, Au13CO, Au13H2 and Au55 clusters to discuss the catalytic behavior of Au clusters with different sizes and structures for CO oxidation. From these calculations, it was found that O2 and CO could adsorb onto several Au model systems. Especially, icosahedral Au13 cluster has a relatively weak interaction with O2 while both icosahedral and cubooctahedral Au13 clusters have interactions (∼20 kcal/mol) with CO. These findings suggest that the surfaces of the Au clusters are the active sites for the catalytic reactions on the supported and unsupported Au catalysts.