Nanoshaped CuO/CeO₂ Materials: Effect of the Exposed Ceria Surfaces on Catalytic Activity in N₂O Decomposition Reaction

This study reports a thorough investigation of nanosized CuO/CeO2 materials as an efficient catalyst for decomposition of N2O, which is a strong greenhouse gas largely produced by chemical industry. Effect of terminating CeO2 crystalline planes ({100}, {110}, and {111}) on the behavior of CuO dispersed over CeO2 nanocubes, nanorods and polyhedral crystallites was examined in detail by using a variety of catalyst characterization techniques. The 4 wt % Cu was found as the most advantageous metal loading, whereas higher Cu content resulted in lower dispersion and formation of significantly less active, segregated bulk CuO phase. It was discovered that CuO/CeO2 solids should enable both excessive oxygen mobility on the catalyst surface as well as formation of highly reducible Cu defect sites, in order to ensure high intrinsic activity. Detailed studies further revealed that CeO2 morphology needs to be tailored to expose {100} and {110} high-energy surface planes, as present in CeO2 nanorods. Oxygen mobility ...