| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Spectroscopic Methods and Analysis for Nuclear Energy Related Materials
|
| Presentation Title |
Investigation of Local Defects in Ln-doped UO2: Impact of Fabrication Condition and Lanthanide type |
| Author(s) |
Juejing Liu, Shinhyo Bang, Arjen van Veelen, Joshua White, Nicolas Dacheux, Xiaofeng Guo |
| On-Site Speaker (Planned) |
Juejing Liu |
| Abstract Scope |
The local structure and chemical behavior of lanthanide (Ln) dopants significantly impact the properties of uranium dioxide (UO₂). We investigates how fabrication conditions (non-reduced vs.) influence the lattice structure and oxidation resistance of Ln-doped UO₂ (Ln = Ce, Nd, Gd) using X-ray absorption fine structure (XAFS) and high-temperature X-ray diffraction (HT-XRD). Ce readily forms a solid solution with UO₂, exhibiting minimal distortion regardless of fabrication conditions. In contrast, trivalent Nd and Gd dopants induce significant lattice distortion, particularly under reduced conditions. This distortion is attributed to different charge compensation mechanisms, with oxygen vacancies aggregating near Ndł⁺ cations to alleviate strain in reduced samples, while increased U(V) formation dominates in non-reduced samples. Gd-doped UO₂ demonstrates enhanced oxidation resistance compared to Nd-doped UO₂, linked to the smaller ionic radius of Gd(III). These findings offer valuable insights for nuclear forensics, fuel development, and spent nuclear fuel management. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Nuclear Materials, Ceramics, |