INFLUENCE OF CERIUM CONTENT AND OF TRANSITION METAL ON THE CERIUM LIII ABSORPTION OF Pd-Ce/Al2O3 CATALYSTS
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VALENCE CHANGE IN THE Pd-Ce SYSTEM
We report X-Ray Absorption and X-Ray Photoemission measurements on crystal l ine and amorphous Pdl-xCex alloys. I n this system, cerium presents a concentration-induced valence change. A correlat ion between cerium electronic configuration and density of occupied states have been shown.Valence anomalies appear to be due t o the high palladium 4d density of states near the Ferrni level. The effe...
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Cobalt catalysts supported on γ-alumina, ceria and γ-alumina-ceria, with 10 or 20%wt of cobalt load, prepared by the wet impregnation method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), field emission transmission electron microscopy (FETEM), N2 adsorptiondesorption isotherms (BET/BJH methods), energy-dispersive X-ray spectroscopy (EDX), X-ray photoemission ...
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