UH3 produced at the initial stage of U-H2O corrosion

The characteristic Raman spectra of UH3 produced at the initial stage of U-H2O corrosion were observed, which provided direct evidence of the existence of water-formed interfacial UH3. The results were further identified and confirmed using the isotopic labelling method and other characterization techniques. The water-formed hydride layer was distributed at the interface of metallic uranium and oxide exhibiting several nanometers of thickness via the depth profile analysis. The characterizations of oxidation behavior suggested that the interfacial UH3 transformed to oxide and acted as a reaction front in the corrosion process. The experimental results supported the hydride-catalyzed corrosion mechanism of wet oxidation.