Preparation and characterization of mesostructured cellular foam silica supported Cu–Ce mixed oxide catalysts for CO oxidation

Abstract

In this paper, a series of mesostructured cellular foam (MCF) silica supported CuO–CeO₂ catalysts (CuO–CeO₂/MCF) with various total metal loadings (10–40 wt%) and various Cu/Ce ratios (Cu/Ce = 1/9, 2/8, and 3/7 wt/wt) were prepared by using a co-impregnation method. Their physicochemical properties and catalytic activity were investigated by various techniques including XRD, TEM, N₂ adsorption–desorption, Raman, XPS, H₂-TPR, CO-TPD, and a low-temperature CO oxidation reaction test. The results show that the catalyst with a bimetallic loading of 30 wt% and Cu/Ce ratio of 2 : 8 (wt/wt) has the highest catalytic activity, which can be attributed to the largest amount of finely dispersed Cu species strongly interacting with CeO₂, the highest concentrations of oxygen vacancies and active lattice oxygen, and the largest amount of Cu⁺ (the better CO adsorption sites).