Please use this identifier to cite or link to this item:
|Title:||Extreme multi-valence states in mixed actinide oxides|
|Authors:||EPIFANO ENRICA; NAJI MOHAMED; MANARA DARIO; SCHEINOST ANDREAS; HENNIG CHRISTOPH; LECHELLE J.; KONINGS RUDY; GUENEAU CHRISTINE; PRIEUR DAMIEN; VITOVA T.; DARDENNE K.; ROTHE J.; MARTIN PHILIPPE|
|Citation:||NATURE MATERIALS vol. 2 no. 59|
|Publisher:||NATURE PUBLISHING GROUP|
|Type:||Articles in periodicals and books|
|Abstract:||To assure the safety of oxide-fuel based nuclear reactors, the knowledge of the atomic-scale properties of U1−yMyO2±x materials is essential. These compounds show complex chemical properties, originating from the fact that actinides and rare earths may occur with different oxidation states. In these mostly ionic materials, aliovalent cationic configurations can induce changes in the oxygen stoichiometry, with dramatic effects on the properties of the fuel. First studies on U1−yAmyO2±x indicated that these materials exhibit particularly complex electronic and local-structure configurations. Here we present an in-depth study of these compounds, over a wide compositional domain, by combining XRD, XAS and Raman spectroscopy. We provide evidences of the co-existence of four different cations (U4+, U5+, Am3+, Am4+) in U1−yMyO2±x compounds, which nevertheless maintain the fluorite structure. Indeed, we show that the cationic sublattice is basically unaffected by the extreme multi-valence states, whereas complex defects are present in the oxygen sublattice.|
|JRC Directorate:||Nuclear Safety and Security|
Files in This Item:
There are no files associated with this item.
Items in repository are protected by copyright, with all rights reserved, unless otherwise indicated.