中国物理B ›› 2018, Vol. 27 ›› Issue (9): 97303-097303.doi: 10.1088/1674-1056/27/9/097303

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Ab initio study of H/O trapping and clustering on U/Al interface

Wenhong Ouyang(欧阳文泓), Wensheng Lai(赖文生), Zhengjun Zhang(张政军)   

  1. Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
  • 收稿日期:2018-03-15 修回日期:2018-06-22 出版日期:2018-09-05 发布日期:2018-09-05
  • 通讯作者: Wensheng Lai E-mail:wslai@tsinghua.edu.cn
  • 基金资助:

    Project supported by Science Challenge Project of China (Grant No. TZ2016002) and the National Key R&D Program of China (Grant No. 2017YFB0702201).

Ab initio study of H/O trapping and clustering on U/Al interface

Wenhong Ouyang(欧阳文泓), Wensheng Lai(赖文生), Zhengjun Zhang(张政军)   

  1. Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
  • Received:2018-03-15 Revised:2018-06-22 Online:2018-09-05 Published:2018-09-05
  • Contact: Wensheng Lai E-mail:wslai@tsinghua.edu.cn
  • Supported by:

    Project supported by Science Challenge Project of China (Grant No. TZ2016002) and the National Key R&D Program of China (Grant No. 2017YFB0702201).

摘要:

Al coating on U surfaces is one of the methods to protect U against environmental corrosion. The behaviors of hydrogen and oxygen impurities near the Al/α-U interface have been studied in the density functional theory framework. It turns out that U vacancies tend to segregate to the interface with segregation energies of around 0.5-0.8 eV. The segregated U vacancy can act as a sink for H and O impurities, which is saturated when filled with 8 H or 6 O atoms, respectively. Moreover, the O impurities tend to stay in the Al layer while the H impurities prefer to diffuse into the U lattice, suggesting that the Al coating can play a significant role against oxidation but not against hydrogenation of U.

关键词: interface, uranium, aluminum, density functional theory

Abstract:

Al coating on U surfaces is one of the methods to protect U against environmental corrosion. The behaviors of hydrogen and oxygen impurities near the Al/α-U interface have been studied in the density functional theory framework. It turns out that U vacancies tend to segregate to the interface with segregation energies of around 0.5-0.8 eV. The segregated U vacancy can act as a sink for H and O impurities, which is saturated when filled with 8 H or 6 O atoms, respectively. Moreover, the O impurities tend to stay in the Al layer while the H impurities prefer to diffuse into the U lattice, suggesting that the Al coating can play a significant role against oxidation but not against hydrogenation of U.

Key words: interface, uranium, aluminum, density functional theory

中图分类号:  (Electron states at surfaces and interfaces)

  • 73.20.-r
68.55.Ln (Defects and impurities: doping, implantation, distribution, concentration, etc.) 73.20.Hb (Impurity and defect levels; energy states of adsorbed species)