Dissolution kinetics of CeO 2 powders with different morphologies and analogy to PuO 2 dissolution

Size Effects in Nanocrystalline Thoria

“…The preservation of NPs' phase composition and morphology during hydrothermal treatment, especially in strongly alkaline media, is not typical for tetravalent metal oxides. For instance, CeO2, which is generally considered a structural analogue of actinide(IV) oxides, [50][51][52][53] tends to change its morphology from nearly spherical particles to nanorods, with an increase in the temperature of hydrothermal treatment under strongly alkaline conditions. 54 The same trend is observed for ZrO2, which is also considered to be an analogue of actinide(IV) oxides.…”

Overlooked impact of surface hydroxylation on the solubility of less-soluble compounds: a case study of CeO2

“…Previously, the dissolution kinetics of cerium dioxide in various media were studied in short-term experiments onlyfrom several hours to several months. 27,28,55 The long-term behaviour (over a matter of years) of CeO 2 -based nanomaterials in solutions is poorly understood. At the same time, the long-term processes could profoundly influence NPs' ecological and health risk assessments.…”

Oxidative dissolution of (U,Ce)O2 materials in aqueous solutions containing H2O2

“…The similarities between the crystallographic (Supplementary Table 1) and the thermodynamic properties of the U-Ce-O and U-Pu-O systems makes their oxidation and phase behavior quite comparable 35 . However, if the analogy between the two systems has been validated for MOX fuel fabrication, thermal and sintering behavior [36][37][38][39] , there is little evidence in the literature for similar alteration mechanism in aqueous solutions (at the noticeable exception of dissolution in concentrated nitric acid solutions [40][41][42] ). It is noteworthy that the Ce(IV) and Pu(IV) standard hydrolysis constants are close and the solubility of the two MO 2 oxides very low (Supplementary Table 1).…”