Syntheses and Applications of Noble-Metal-free CeO2-Based Mixed-Oxide Nanocatalysts

CeO2-based mixed oxides as non-noble-metal catalysts have received tremendous attention because of their great importance for both fundamental studies and catalytic applications. Compared with single-component samples, the interface in the mixed oxides could largely optimize the crucial steps for a heterogeneous catalytic reaction, such as the adsorption rate of substrate molecules, the intermediate states, and the desorption rate of the products. This review summarizes the recent development in the syntheses of nanostructured noble-metal-free CeO2-based mixed-oxide catalysts, as well as their catalytic applications in some model reactions, such as CO oxidation, NOx reduction, steam reforming, water-gas shift reaction, photocatalytic reaction, and so on. The synthetic strategy, component, and structure effect for their enhanced catalytic performances are the focus of our attention. Finally, we conclude this review with remarks on some challenges and perspectives in this emerging area of research.