Morphology of rhodium particles in ex-chloride Rh/Ce{sub 0.5}Zr{sub 0.5}O{sub 2} catalyst

Journal Article · Tue Feb 15 04:00:00 EST 2000 · Journal of Catalysis

DOI:https://doi.org/10.1006/jcat.1999.2731· OSTI ID:20017459

Vlaic, G; Fornasiero, P; Martra, G; Fonda, E; Kaspar, J; Marchese, L; Tomat, E; Coluccia, S; Graziani, M

The morphology of rhodium particles in a 5 wt% Th/Ce{sub 0.5}Zr{sub 0.5}O{sub 2} catalyst subjected to different treatments is investigated by EXAFS, HREM, and H{sub 2} chemisorption. Despite the high Rh loading, highly dispersed metal particles are observed in the sample. In the presence of NO and CO, the Th particles are easily oxidized to give small TH oxide clusters, and the high rhodium dispersion is retained even after a further reduction at 773 K. Comparison with an Rh/Al{sub 2}O{sub 3} prepared under identical conditions clearly suggests that the presence of the Ce{sub 0.5}Zr{sub 0.5}O{sub 2} support favors high dispersion of rhodium particles. Despite the fact that RhCl{sub 3}{sm{underscore}bullet}nH{sub 2}O has been employed as precursor, no chloride could be detected in the Rh nearest-neighbor shell, suggesting its migration over the support.

• Research Organization: Univ. di Trieste (IT)
• OSTI ID: 20017459
• Journal Information: Journal of Catalysis, Journal Name: Journal of Catalysis Journal Issue: 1 Vol. 190; ISSN 0021-9517; ISSN JCTLA5
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
36 MATERIALS SCIENCE
54 ENVIRONMENTAL SCIENCES
AIR POLLUTION CONTROL
CATALYSTS
CATALYTIC CONVERTERS
EXHAUST GASES
MORPHOLOGY
PHASE STUDIES
RHODIUM
SURFACE PROPERTIES