Acta Phys. -Chim. Sin. ›› 1992, Vol. 8 ›› Issue (04): 452-458.doi: 10.3866/PKU.WHXB19920406

• ARTICLE • Previous Articles     Next Articles

The Characteristic Behavior of H2 and O2 Over CeO2 and Pt/CeO2 Catalysts

Chen Yan-Xin; Li Can; Li Wen-Zhao; Chen Yi-Xuan   

  1. Dalian Institute of Chemical Physics, Academia Sinica, Dalian 116023
  • Received:1991-02-11 Revised:1991-08-10 Published:1992-08-15
  • Contact: Chen Yan-Xin

Abstract: The characteristic behavior of H_2 and O_2 over CeO_2 and Pt/CeO_2 was studied by means of TPR, TPD, FT-IR and TPEC. The reduction of CeO_2 by H_2 is greatly promoted by supported Pt and highly labile adsorbed species is resulted. The temperatures of sorption and liberation of H_2 on Pt/CeO_2 are lowered by as much as 300 ℃ than on CeO_2. The oxygen adsorbed on partially reduced CeO_2 exists as dioxygen species(O_2~-,O_2~(2-)) at room temperature. On Pt/CeO_2 the oxygen species is altered and the dissociated species is formed even at ambient condition. The adsorbed oxygen on cerium oxide catalysts desorbs partly while the temperature is elevated and the retained oxygen is transformed into lattice oxygen ion above 170 ℃.

Key words: Catalyst, Oxidation, CeO2, Pt