Metal–support interaction in Pd/CeO 2 catalysts: Fourier-transform infrared studies of the effects of the reduction temperature and metal loading. Part 1.—Catalysts prepared by the microemulsion technique

作者：Claude Binet, Ahmed Jadi, Jean‐Claude Lavalley, Magali Boutonnet-Kizling · 发表于：Journal of the Chemical Society Faraday Transactions · 年份：1992 · DOI：10.1039/ft9928802079 · 被引用次数：62 · 研究领域：Catalytic Processes in Materials Science、Catalysis and Oxidation Reactions、Electrocatalysts for Energy Conversion

The effect of the temperature of reduction by H2 of Pd/CeO2 catalysts on the accessibility of the metal to carbon monoxide adsorption has been estimated from a study of the integrated intensity of the ν(CO) absorption bands. No adsorption occurred when the reduction temperature was higher than 673 K; the behaviour of the catalysts, which present crystallites of the same morphology, appeared to be independent of the Pd loading (0.5, 2.5, 5 wt.%). the adsorption could be completely recovered when the catalysts were first reoxidized at 723 K and subsequently reduced by H2 at 423 K: this characterized the occurrence of a strong metal–support interaction (SMSI). Study of the ν(CO) absorption bands corresponding to CO adsorption on the (100) and (111) planes tended to show only a weak selectivity of the (100) planes in the SMSI phenomenon. The effect of the reduction on the ceria support was established from the study of methanol and tetracyanoethylene adsorption; surface ceria reduction was enhanced owing to the presence of palladium metal.