UO2 oxidative corrosion by non-classical diffusion

Journal Article · Mon Jun 01 00:00:00 EDT 2015 · Physical Review Letters, 114(24):246103

DOI:https://doi.org/10.1103/PhysRevLett.114.246103· OSTI ID:1203894

Stubbs, Joanne; Chaka, Anne M.; Ilton, Eugene S.; Biwer, Craig A.; Engelhard, Mark H.; Bargar, John R.; Eng, Peter

Using x-ray scattering, spectroscopy, and computational methods, we show that oxidation of the UO2 (111) surface results in a self-organized arrangement of oxygen interstitials with three-layer periodicity, producing a nanoscale oscillatory oxidation front with uranium in three oxidation states: IV, V, and VI. This complex diffusion profile is driven by the transfer of the lowest energy U5f electrons from multiple U atoms into the O2p band. Our results contrast with all previous bulk structural oxidation models and the simple exponential oxidation front expected from classical diffusion.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1203894
• Report Number(s): PNNL-SA-108810; 48555; KC0302060
• Journal Information: Physical Review Letters, 114(24):246103, Journal Name: Physical Review Letters, 114(24):246103
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory