Strong Impact of Support Morphology on Catalytic Decomposition of N2O over Rh/CeO2 Catalysts
N2O is a potent greenhouse gas, and its catalytic decomposition is of significant environmental importance. In this study, three CeO2 supports with different morphologies—nanorods (NR), nanocubes (NC), and nanooctahedra (NO)—were prepared via a hydrothermal method. Rh catalysts supported on these CeO2 materials were synthesized using a deposition-precipitation method, and their catalytic performance for N2O decomposition was evaluated. Results demonstrate that Rh/CeO2-NR exhibits superior catalytic activity compared to Rh/CeO2-NC and Rh/CeO2-NO under identical reaction conditions, including in the presence of O2 and H2O. Characterization reveals that Rh/CeO2-NR possesses abundant oxygen vacancies and a relatively high number of intrinsic defect sites, which facilitate the transfer of O intermediates. Additionally, Rh/CeO2-NR exhibits an appropriate Rh0/Rhn+ ratio, promoting the redox cycle between Rh species and reactants, thereby enhancing catalytic activity. The study underscores the critical role of CeO2 support morphology in optimizing Rh-based catalysts for N2O decomposition, offering a strategy to improve catalytic efficiency and stability for industrial applications.