Pre- and post-oxidation Raman analysis of (U, Ce)O2 oxides

A pre- and post-oxidation detailed Raman analysis has been carried out on a variety of (U1-y,Cey)O2-x oxides (y = 0.01, 0.03, 0.10, 0.15, 0.40). The changes undergone in the Raman spectrum of UO2 as a function of Ce incorporation have been examined, thus extracting valuable information on the structural features and changes of these solid solutions, including the presence of vacancies in the cations' surroundings. Comparison of the results extracted from the post-oxidation analyses of Ce-containing samples with those obtained for pure UO2 confirms that a Ce content as low as 1 mol% leads to a protective effect on the dioxide matrix against oxidation and that, under identical conditions, the oxidation process is slowed down as Ce concentration increases.