Investigating the role of irradiation defects during UO2 oxidative dissolution

In this study, the behavior of alpha irradiation-induced defects in UO2, when exposed to different interfaces, is investigated. Raman spectroscopy is used to measure the formation kinetics of irradiation defects in UO2 leached under oxidizing water environment and the data are then compared to a reference UO2/Ar system. The results reveal that the presence of either aerated water or inert argon gas modifies the formation kinetics of irradiation defects. The UO2 alteration in aerated water leads to the precipitation of secondary phases in the form of studtite and water chemical analysis reveals that the UO2 dissolution mechanism proceeds without the formation of an oxidized UO2 layer. (C) 2018 Elsevier B.V. All rights reserved.