Effect of high temperature lean aging on the performance of Pt, Rh/CeO2 and rare earth/alkaline earth doped Pt, Rh/CeO2 catalysts

摘要: Abstract The effect of high temperature lean aging on the performance and physico-chemical properties a series Pt, Rh/CeO 2 catalysts doped with rare earths Ba has been studied. Catalyst was evaluated in full complement exhaust gas mixture containing H , CO, C 3 6 8 NO, CO O, N SO . It found that doping CeO lattice such as La, Y Nd leads to severe loss activity after aging. undoped showed extensive activation exposure rich mixtures. Characterization aged using TPR correlated decoupling low synergistic reduction noble metal (NM) surface Ce. mixtures further shows catalyst subsequent associated both NM In situ XPS analysis earth led migration or burial support accompanying retardation Ce reduction. results are consistent previously proposed hypothesis active state is reduced contact NM.