Decomposition of N2O on Rh-loaded Pr/Ce composite oxides

The effect of the addition of Pr on the nature of the lattice oxygen of CeO 2 was investigated. In order to enhance the mobility of the lattice oxygen for monitoring, Rh (2 wt.%) was supported on the Pr/Ce composite oxides whi ch were calcined at various temperatures. The decomposition of N2O was empl oyed as a test reaction. Although an addition of Pr to CeO2 had only a smal l effect when the composite oxides were calcined at low temperature (600 de grees C), it had a large accelerating effect for N2O decomposition when the calcination temperature was increased. Especially the performance of the P h-supported composite oxide with 20 mol% of Pr calcined at 800 degrees C wa s higher than that of Rh/CeO2 in which CeO2 was calcined at 600 degrees C. Oxygen desorbed more easily from the catalysts containing Pr than from Rh/C eO2. Thus, the interaction of Pr with CeO2 increased the mobility of the ox ygen of the latter, leading to the high activity of the catalysts to decomp ose N2O. (C) 2000 Elsevier Science B.V. All rights reserved.