Abstract
Pt–Rh/CeO2/Al2O3 was successfully synthesized by a hydrothermal method, and its chemical and physical properties as well as catalytic activity were evaluated. Pt–Rh/CeO2/Al2O3 was also prepared by a conventional impregnation method synthesis method for comparative purposes. The Pt–Rh/CeO2/Al2O3 synthesized by the hydrothermal method was found to comprise hollow CeO2 nanorods coated with nanoparticle arrays, with the CeO2 surfaces being selective supports for Pt and Rh. Furthermore, although the light-off temperatures of NO and C3H6 were similar between the Pt–Rh/CeO2/Al2O3 catalysts prepared by the two different methods, the hydrothermally synthesized Pt–Rh/CeO2/Al2O3 exhibited a lower light-off temperature of CO compared to the one synthesized by the impregnation method. The hydrothermally synthesized Pt–Rh/CeO2/Al2O3 also exhibited a higher catalytic activity, which was attributed to its better dispersion of Pt and Rh compared to the impregnation one.
