Catalytic activity of ceria-based solid solutions with low-content dopants

Abstract

Ceria-based solid solutions (M0.01Ce0.99O2) with low-content dopants were synthesized by the co-precipitation method, followed by calcination at the temperature of 500 °C. The effect of doping on catalytic performance in CO oxidation was investigated, and the catalyst physicochemical properties were studied. The introduction of even a small amount of metal dopants significantly increased the activity of catalysts. Thus, the most active catalysts were systems when doping ceria with metals Cu, Mn, and Co, i.e., with a small ionic radius and having multivalent oxidation states. It is shown that the high activity was a result of the increased interaction of Mδ+ with ceria due to facile electron exchange between Mδ+ and Ce4+/Ce3+, the redox cycle was one of the key factors in the CO oxidation, as well as well-integrated metal species in ceria lattice, especially in subsurface layer.