Properties of cerium-zirconium mixed oxides partially substituted by neodymium: Comparison with Zr-Ce-Pr-O ternary oxides
- Laboratoire de Catalyse en Chimie Organique, UMR 6503, CNRS et Universite de Poitiers, 40 Avenue du Recteur Pineau, 86022 Poitiers (France)
CeO{sub 2} doped with praseodymium, neodymium and/or zirconium atoms were prepared by coprecipitation and by the sol-gel method. Structural properties were investigated by in situ XRD and Raman spectroscopy while oxygen storage capacity (OSC) was measured by transient CO oxidation. All the compounds, except pure Nd{sub 2}O{sub 3}, have a fluorite-type structure as well as a Raman band at 560 cm{sup -1} characteristic of the oxygen vacancies involving non-stoichiometric oxides. The lattice parameter under hydrogen, being dependent on the temperature, revealed two reduction mechanisms: one at a low temperature at the surface and another at a high temperature in the bulk. Ce-Nd binary oxides show a strong tendency towards crystallite aggregation, which reduces accessibility to gases and OSC properties. Zirconium improves the thermal resistance to sintering of both Ce-Nd and Ce-Pr oxides. The Zr-Ce-Pr-O followed by Zr-Ce-Nd-O compounds displaying high oxygen mobility at a low temperature, appear to be very promising for practical applications such as OSC materials. - Graphical abstract: Variation of oxygen vacancies under hydrogen on ternary oxides.
- OSTI ID:
- 20905403
- Journal Information:
- Journal of Solid State Chemistry, Vol. 179, Issue 8; Other Information: DOI: 10.1016/j.jssc.2006.04.051; PII: S0022-4596(06)00239-8; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
Similar Records
THE SPECTROSCOPIC DETERMINATION OF SMALL CONCENTRATIONS OF LANTHANUM, PRASEODYMIUM, NEODYMIUM, AND YTTRIUM IN CERIUM
Structural and catalytic properties of lanthanide (La, Eu, Gd) doped ceria