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Cheng JX, Yang F, Wang QB, He YY, Liu YN, Hu ZY, Wen WW, Wu YP, Zheng CY, Yu A, Lu X, Zhang Y. First-Principles Study on Mechanical and Optical Behavior of Plutonium Oxide under Typical Structural Phases and Vacancy Defects. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7785. [PMID: 36363381 PMCID: PMC9656257 DOI: 10.3390/ma15217785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 10/29/2022] [Accepted: 11/02/2022] [Indexed: 06/16/2023]
Abstract
The chemical corrosion aging of plutonium is a very important topic. It is easy to be corroded and produces oxidation products of various valence states because of its 5f electron orbit between local and non-local. On the one hand, the phase diagram of plutonium and oxygen is complex, so there is still not enough research on typical structural phases. On the other hand, most of the studies on plutonium oxide focus on PuO2 and Pu2O3 with stoichiometric ratio, while the understanding of non-stoichiometric ratio, especially for Pu2O3-x, is not deep enough. Based on this, using the DFT + U theoretical scheme of density functional theory, we have systematically studied the structural stability, lattice parameters, electronic structure, mechanical and optical properties of six typical high temperature phases of β-Pu2O3, α-Pu2O3,γ-Pu2O3, PuO, α-PuO2,γ-PuO2. Further, the mechanical properties and optical behavior of Pu2O3-x under different oxygen vacancy concentrations are analyzed and discussed in detail. The result shows that the elasticity modulus of single crystal in mechanical properties is directly related to the oxygen/plutonium ratio and crystal system. As the number of oxygen vacancies increases, the mechanical constants continue to increase. In terms of optical properties, PuO has the best optical properties, and the light absorption rate decreases with the increase of oxygen vacancy concentration.
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Affiliation(s)
- Jin-Xing Cheng
- Beijing Institute of High Technology, Beijing 100094, China
| | - Fei Yang
- College of Mathematics and Physics, Beijing University of Chemical Technology, Beijing 100029, China
| | - Qing-Bo Wang
- Beijing Institute of High Technology, Beijing 100094, China
| | - Yuan-Yuan He
- College of Mathematics and Physics, Beijing University of Chemical Technology, Beijing 100029, China
| | - Yi-Nuo Liu
- College of Mathematics and Physics, Beijing University of Chemical Technology, Beijing 100029, China
| | - Zi-Yu Hu
- College of Mathematics and Physics, Beijing University of Chemical Technology, Beijing 100029, China
| | - Wei-Wei Wen
- Beijing Institute of High Technology, Beijing 100094, China
| | - You-Peng Wu
- Beijing Institute of High Technology, Beijing 100094, China
| | | | - Ai Yu
- Beijing Institute of High Technology, Beijing 100094, China
| | - Xin Lu
- Beijing Institute of High Technology, Beijing 100094, China
| | - Yue Zhang
- Beijing Institute of High Technology, Beijing 100094, China
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Huang S, Ma JJ, Lai K, Zhang CB, Yin W, Qiu R, Zhang P, Wang BT. Point Defects Stability, Hydrogen Diffusion, Electronic Structure, and Mechanical Properties of Defected Equiatomic γ(U,Zr) from First-Principles. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7452. [PMID: 36363044 PMCID: PMC9656540 DOI: 10.3390/ma15217452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 10/14/2022] [Accepted: 10/20/2022] [Indexed: 06/16/2023]
Abstract
At present, many experimental fast reactors have adopted alloy nuclear fuels, for example, U-Zr alloy fuels. During the neutron irradiation process, vacancies and hydrogen (H) impurity atoms can both exist in U-Zr alloy fuels. Here, first-principles density functional theory (DFT) is employed to study the behaviors of vacancies and H atoms in disordered-γ(U,Zr) as well as their impacts on the electronic structure and mechanical properties. The formation energy of vacancies and hydrogen solution energy are calculated. The effect of vacancies on the migration barrier of hydrogen atoms is revealed. The effect of vacancies and hydrogen atom on densities of states and elastic constants are also presented. The results illustrate that U vacancy is easier to be formed than Zr vacancy. The H interstitial prefers the tetrahedral site. Besides, U vacancy shows H-trap ability and can raise the H migration barrier. Almost all the defects lead to decreases in electrical conductivity and bulk modulus. It is also found that the main effect of defects is on the U-5f orbitals. This work provides a theoretical understanding of the effect of defects on the electronic and mechanical properties of U-Zr alloys, which is an essential step toward tailoring their performance.
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Affiliation(s)
- Shasha Huang
- Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing 100049, China
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China
- Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China
| | - Jiang-Jiang Ma
- Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing 100049, China
- Spallation Neutron Source Science Center (SNSSC), Dongguan 523803, China
| | - Kan Lai
- Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China
| | - Cheng-Bin Zhang
- Department of Basic Education, Tangshan University, Tangshan 063000, China
| | - Wen Yin
- Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing 100049, China
- Spallation Neutron Source Science Center (SNSSC), Dongguan 523803, China
| | - Ruizhi Qiu
- Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang 621908, China
| | - Ping Zhang
- LCP, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
| | - Bao-Tian Wang
- Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing 100049, China
- Spallation Neutron Source Science Center (SNSSC), Dongguan 523803, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
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First-Principle and Atomistic Modelling in Materials Science. MATERIALS 2021; 14:ma14061469. [PMID: 33802776 PMCID: PMC8002450 DOI: 10.3390/ma14061469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 11/17/2022]
Abstract
In the last two decades, the importance of Computational Materials Science has continuously increased due to the steadily growing availability of computer power [...].
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