Influence of crystallite size and interface on the catalytic performance over the CeO2/CuO catalysts

Abstract

The solvothermal method was used to prepare the CuO precursor with cotton-ball-like morphology in order to obtain the CeO2/CuO catalysts with high BET surface area. The catalysts were characterized via SEM, XRD, H2-TPR, ICP, HRTEM and N2 adsorption–desorption techniques. The study shows that CeO2 and CuO interact on the contact interface. The interaction of oxides switches on CO oxidation at 55 °C and the synergistic effect of interaction also improves H2 oxidation at 95 °C. CO oxidation takes place at the contact interface of CeO2 and CuO. The high BET surface area and good dispersion of catalysts can be more helpful for the presence of accumulated long periphery at interface of CeO2 and CuO than the larger CeO2 particles when most of CeO2 particles pile into the small clusters and distribute on the bulk CuO. The CeO2/CuO catalyst with 1:2 Ce/Cu molar ratio has the highest BET surface area and better dispersion of CeO2 among the catalysts, therefore it display good catalytic activity, selectivity and stability.