Dissolution of Cerium(IV)–Lanthanide(III) Oxides: Comparative Effect of Chemical Composition, Temperature, and Acidity

• DOI: 10.1021/ic300071c
• Publication Date: 2012-02-29T16:04:25Z
• Authors: D. Horlait; N. Clavier; S. Szenknect; N. Dacheux; V. Dubois
• Keywords: 01 natural sciences; 0104 chemical sciences

The dissolution of Ce1–xLnxO2–x/2 solid solutions was undertaken in various acid media order to evaluate the effects several physicochemical parameters such as chemical composition, temperature, and acidity on reaction kinetics. normalized rates (RL,0) were found be strongly modified by trivalent lanthanide incorporation rate, due presence oxygen vacancies decreasing samples cohesion. Conversely, nature cation considered only weakly impacted RL,0 values. dependence temperature then appeared same magnitude than that composition. Moreover, it allowed determining corresponding activation energy (EA ≈ 60–85 kJ·mol–1) which accounts for a driven surface-controlled reactions. A similar conclusion made regarding solution: partial related (H3O+) reaching about 0.7. Finally, prevailing effect aliovalent cations fluorite-type CeO2 matrix kinetics precluded observation slight those linked complexing agents or crystal structure samples.