Two Gold Surfaces and a Cluster with Remarkable Reactivity for CO Oxidation, a Density Functional Theory Study

We calculate the energetics of CO oxidation on extended surfaces of particular structures chosen to maximize their reactivity towards either O-2 dissociation, after which CO + O to CO2 is a facile reaction, or to CO2 from molecular O-2 and CO. We identified two configurations of Au atoms for which the energetics of these reactions are feasible. A site consisting of four Au atoms in a square geometry appears well suited for dissociating oxygen. A Au-38 cluster exposing this site provides the most favourable energetics for the CO oxidation.