Speciation mapping of the oxidation layer on aged uranium dioxide using scanning transmission x-ray spectromicroscopy

IF 2.8 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials Pub Date : 2025-04-03 DOI:10.1016/j.jnucmat.2025.155792

Nic Cicchetti , Alexander Ditter , Joseph I. Pacold , Zurong Dai , Scott B. Donald , Brandon W. Chung , M. Lee Davisson , Artem V. Gelis , David K. Shuh

{"title":"Speciation mapping of the oxidation layer on aged uranium dioxide using scanning transmission x-ray spectromicroscopy","authors":"Nic Cicchetti , Alexander Ditter , Joseph I. Pacold , Zurong Dai , Scott B. Donald , Brandon W. Chung , M. Lee Davisson , Artem V. Gelis , David K. Shuh","doi":"10.1016/j.jnucmat.2025.155792","DOIUrl":null,"url":null,"abstract":"<div><div>In this study, UO<sub>2</sub> was aged in humid air and prepared as a thin section using a focused ion beam (FIB) instrument. The specimen was measured using synchrotron radiation spectromicroscopy techniques at the Beamline 11.0.2 STXM end station of the Advanced Light Source (ALS). Non-negative matrix factorization (NMF) methods were used to identify and map three component x-ray absorption near-edge structure (XANES) spectra in the oxygen K-edge data, revealing a surface layer of U<sub>4</sub>O<sub>9</sub> with a thickness of 206 ± 21 nm, and the bulk of the sample remaining as UO<sub>2</sub>. Uranium N<sub>4,5</sub>-edge XANES spectromicroscopy supports these results. The diffusion-controlled parabolic rate constant for UO<sub>2</sub> oxidation to U<sub>4</sub>O<sub>9</sub> was calculated from the observed layer thickness and compared to literature values. Complementary transmission electron microscopy (TEM) was used to image the sample and identify the phases present in various regions, confirming the STXM results.</div></div>","PeriodicalId":373,"journal":{"name":"Journal of Nuclear Materials","volume":"612 ","pages":"Article 155792"},"PeriodicalIF":2.8000,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Nuclear Materials","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022311525001874","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}

引用次数: 0

Abstract

In this study, UO₂ was aged in humid air and prepared as a thin section using a focused ion beam (FIB) instrument. The specimen was measured using synchrotron radiation spectromicroscopy techniques at the Beamline 11.0.2 STXM end station of the Advanced Light Source (ALS). Non-negative matrix factorization (NMF) methods were used to identify and map three component x-ray absorption near-edge structure (XANES) spectra in the oxygen K-edge data, revealing a surface layer of U₄O₉ with a thickness of 206 ± 21 nm, and the bulk of the sample remaining as UO₂. Uranium N_4,5-edge XANES spectromicroscopy supports these results. The diffusion-controlled parabolic rate constant for UO₂ oxidation to U₄O₉ was calculated from the observed layer thickness and compared to literature values. Complementary transmission electron microscopy (TEM) was used to image the sample and identify the phases present in various regions, confirming the STXM results.

Abstract Image

查看原文本刊更多论文

用扫描透射x射线光谱显微镜绘制老化二氧化铀氧化层的形态图

在本研究中，UO2在潮湿空气中老化，并使用聚焦离子束（FIB）仪器制备成薄片。在先进光源（ALS）的光束线11.0.2 STXM端站使用同步辐射光谱显微镜技术对样品进行测量。利用非负矩阵分解（NMF）方法对氧k边数据中的三组分x射线吸收近边结构（XANES）光谱进行了识别和映射，发现表层为U4O9，厚度为206±21 nm，样品大部分为UO2。铀n4,5边XANES光谱显微镜支持这些结果。根据观察到的层厚计算了UO2氧化为U4O9的扩散控制抛物线速率常数，并与文献值进行了比较。利用互补透射电子显微镜（TEM）对样品进行成像，并确定了不同区域存在的相，证实了STXM的结果。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Journal of Nuclear Materials 工程技术-材料科学：综合

CiteScore

5.70

自引率

25.80%

发文量

601

审稿时长

63 days

期刊介绍： The Journal of Nuclear Materials publishes high quality papers in materials research for nuclear applications, primarily fission reactors, fusion reactors, and similar environments including radiation areas of charged particle accelerators. Both original research and critical review papers covering experimental, theoretical, and computational aspects of either fundamental or applied nature are welcome. The breadth of the field is such that a wide range of processes and properties in the field of materials science and engineering is of interest to the readership, spanning atom-scale processes, microstructures, thermodynamics, mechanical properties, physical properties, and corrosion, for example. Topics covered by JNM Fission reactor materials, including fuels, cladding, core structures, pressure vessels, coolant interactions with materials, moderator and control components, fission product behavior. Materials aspects of the entire fuel cycle. Materials aspects of the actinides and their compounds. Performance of nuclear waste materials; materials aspects of the immobilization of wastes. Fusion reactor materials, including first walls, blankets, insulators and magnets. Neutron and charged particle radiation effects in materials, including defects, transmutations, microstructures, phase changes and macroscopic properties. Interaction of plasmas, ion beams, electron beams and electromagnetic radiation with materials relevant to nuclear systems.