| AVS 65th International Symposium & Exhibition | |
| Actinides and Rare Earths Focus Topic | Thursday Sessions |
| Session AC+AS+SA-ThM |
| Session: | Nuclear Power, Forensics, and Other Applications |
| Presenter: | Art Nelson, Lawrence Livermore National Laboratory |
| Authors: | A.J. Nelson, Lawrence Livermore National Laboratory S.B. Donald, Lawrence Livermore National Laboratory D.J. Roberts, Lawrence Livermore National Laboratory W. McLean, Lawrence Livermore National Laboratory |
| Correspondent: | Click to Email |
X-ray photoemission spectroscopy (XPS) was used to characterize differences in the oxidation rates for polycrystalline α-Pu versus δ-Pu related to variations in grain size and surface electronic structure. The evolution of the Pu 4f core-level chemical shift as a function of oxygen exposure at ambient temperature was quantified in oxidation profiles. In addition, the X-ray excited Pu NOO Auger line-shapes were combined with the chemical shift of the Pu 4f7/2 photoelectron line that defines the Auger parameter and results in a reliable method for determining oxidation states independent of binding energy calibration. The oxidation profiles reveal that α-Pu oxidizes faster than δ-Pu, both resulting in the PuO2/Pu2O3/Pu oxide structure. This data was used to a produce chemical state (Wagner) plot for select plutonium oxides.
This work was performed under the auspices of the U.S. Dept. of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.