Optimum Balance of Cu+ and Oxygen Vacancies of CuOx-CeO2 Composites for CO Oxidation Based on Thermal Treatment

It is important to exploit non-noble metal catalysts with excellent performance toward CO oxidation. Here, CuOx-CeO2 composites with a size of about 4 nm have been fabricated by a facile and mild in situ route without solvent or liquid reactant involved. The balance between Cu+ concentration and oxygen vacancy on the CeO2 surface, which are beneficial for catalytic activity, can be tailored by the amount of Cu loading and the thermal treatment parameters of composites. The as-obtained CuOx-CeO2 (C-9-6-C) composites with lower Cu loading exhibited excellent CO reactivity and superior stability at lower temperatures, which enable the total oxidation of CO at 110 degrees C. Appropriate heat treatment promoted the available migration of Cu species from the surface to the interior of the CeO2 lattice, which guaranteed the existence of affluent oxygen vacancies. The enhanced activity of CuOx-CeO2 composites can be attributed to the preservation of highly dispersed Cu+ species and oxygen vacancies on the surface of CeO2. Hopefully, the CuOx-CeO2 nanohybrids prepared by this facile and mild route can be used as a promising potential catalyst for CO oxidation with high efficiency and long life.