Metal support interaction of defective-rich CuO and Au with enhanced CO low-temperature catalytic oxidation and moisture resistance
Yahang Wang, Lujun Zhu, Jingwei Li, Weibin Zhang, Xianjin Shi, Yu Huang, Mirabbos Hojamberdiev, Gangqiang Zhu
Abstract
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 H 2 O and O 2 . 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. A catalyst with the ability to oxidize CO at humid room temperature was constructed by loading Au onto CuO rich in oxygen vacancies. Water will compete with CO and O2 for active sites in CO catalysis, which is solved by loading precious metals. This problem is proved by experiment and theoretical calculation. • Humidity sensing is used to detect the dissociation and adsorption of CO oxidation catalysts to H 2 O. • Introduce new sites to overcome competitive adsorption. • Metal-support interaction for catalytic oxidation of CO in humid environment. • Catalytic CO oxidation at room temperature and humidity.