| About this Abstract |
| Meeting |
MS&T21: Materials Science & Technology
|
| Symposium
|
Advanced Characterization of Materials for Nuclear, Radiation, and Extreme Environments
|
| Presentation Title |
Optical Characterization of Defects in Proton Irradiated Fluorite Oxides |
| Author(s) |
Joshua Ferrigno, Vinay Chauhan, Amey Khanolkar, Lingfeng He, David Hurley, Marat Khafizov |
| On-Site Speaker (Planned) |
Joshua Ferrigno |
| Abstract Scope |
Experimental methods to characterize point defects in nuclear energy materials are needed for improved understanding of their irradiation behavior. Inspired by successful implementation of optical spectroscopy to characterize oxygen vacancies (VO) in insulators such as Al2O3 and MgO, we performed optical ellipsometry to characterize irradiation induced defects in CeO2 and ThO2 used as a model fluorite oxide. Polycrystalline CeO2 and single crystal ThO2 were irradiated with protons accelerated up to 2 MeV at various temperatures and dose levels. In ThO2, distinct optical absorption peaks were observed at 1.8 eV and 2.0 eV, while in CeO2, a much broader defect peak at 1.9 eV was identified. The difference in optical spectra are attributed to difference in electronic structure of VO, where electrons are localized in vacancy sites in ThO2 and in cerium atoms in CeO2. This approach demonstrates the potential of optical spectroscopy to characterize point defects in irradiated actinide oxides. |