Metal support interaction of defective-rich CuO and Au with enhanced CO low-temperature catalytic oxidation and moisture resistance

Water is considered to be an inhibitor of CO oxidation. The mechanism of retarding the reaction is thought to contribute to the practical application of CO oxidation, which is investigated by constructing the coupling of Au nanoparticles and defective CuO to form metal-support interactions (MSI) and oxygen vacancies (OVs). The introduction of Au forms a new CO adsorption site, which successfully solves the competitive adsorption problem of CO with H2O and O2. Due to the coupling of MSI and OVs, the reduced ability of catalyst and the activation and migration ability of oxygen are enhanced simultaneously. Au-CuO has the ability to oxidize CO at room temperature with high stability under a humid environment. Theoretical calculation confirmed the competitive adsorption and the influence of MSI and OVs coupling on the catalyst performance. The mechanism of water resistance in CO catalytic oxidation was also explained.