Influence of the redox properties of ceria on the preparation of three-way automotive platinum—rhodium/ alumina—ceria catalysts

The redox properties of ceria were investigated by temperature-programmed reduction performed under hydrogen and the catalysts were evaluated by determining the temperatures at which 50% conversion for propene and propane oxidation were reached. The results obtained show that ceria plays a decisive...

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Bibliographic Details
Published inApplied catalysis. B, Environmental Vol. 5; no. 1-2; pp. 57 - 69
Main Authors Marécot, P., Pirault, L., Mabilon, G., Prigent, M., Barbier, J.
Format Journal Article
LanguageEnglish
Published Amsterdam Elsevier B.V 31.12.1994
Elsevier
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Summary:The redox properties of ceria were investigated by temperature-programmed reduction performed under hydrogen and the catalysts were evaluated by determining the temperatures at which 50% conversion for propene and propane oxidation were reached. The results obtained show that ceria plays a decisive role within the preparation of bimetallic PtRh/Al2O3CeO2 catalysts by successive impregnations (SI) when reduced capping cerium atoms (Ce3+) are present on the parent Pt/Al2O3CeO2 catalyst before introduction of the rhodium salt. Thus, rhodium deposition would occur by a redox reaction between Ce3+ and Rh3+. The preparation procedure of PtRh/Al2O3CeO2 catalysts by the SI method increases the thermal stability of the metallic species under oxidizing conditions. This improvement would be the consequence of a higher resistance to the formation of PtRh alloys with surface enrichment in rhodium.
ISSN:0926-3373
1873-3883
DOI:10.1016/0926-3373(94)00038-7