不同晶体结构的La0.9Sr0.1Ga0.8Mg0.2O3-δ体系氧空位的形成和迁移研究
Oxygen Vacancy Formation and Migration in La0.9Sr0.1Ga0.8Mg0.2O3-δ with Different Crystal Structures
DOI: 10.12677/HJCET.2020.104041, PDF,    科研立项经费支持
作者: 张飞翔, 王 建, 田星原：郑州师范学院，物理与电子工程学院，河南 郑州；孙海杰：郑州师范学院，化学化工学院，河南 郑州
关键词: 固体氧化物燃料电池(SOFC)；氧空位形成能；氧空位迁移能；Solid Oxide Fuel Cell (SOFC)； Oxygen Vacancy Formation Energy； Oxygen Vacancy Migration Energy
摘要: 采用基于密度泛函理论(DFT)的第一性原理方法研究了具有不同晶体对称性(立方、斜方六面体、正交和单斜结构)的La0.9Sr0.1Ga0.8Mg0.2O3−δ(LSGM)体系的氧空位形成和迁移能。结果显示立方结构的LSGM具有最小的氧空位形成能和迁移势垒，而其他三种结构的空位形成能和迁移势垒都比较大，这意味着在四种不同晶体结构的LSGM体系中，立方结构的LSGM具有最好的氧离子电导。本文的计算结果不仅能够解释实验观察到的不同晶体对称性LSGM体系氧离子电导行为的差异，而且能够在一定程度上预言在固体氧化物燃料电池电解质的应用中最理想的晶体结构。
Abstract: The first-principles method based on density functional theory (DFT) was used to study oxygen vacancy formation and migration energy of La0.9Sr0.1Ga0.8Mg0.2O3−δ (LSGM) with different crystal symmetry (cubic, rhombohedral, orthogonal and monoclinic structures). The results show that the cubic LSGM has the smallest oxygen vacancy formation energy and migration barrier, while LSGMs with the other three structures have larger vacancy formation energy and migration barrier, which means that in LSGM systems with four different crystal structure, the cubic LSGM has the best oxygen ion conductivity. The calculation results in this paper can not only explain the difference in oxygen ion conductivity observed in the experiment in the LSGM systems with different crystal symmetry, but also predict the most ideal crystal structure in the application of solid oxide fuel cell electrolyte to a certain extent.
文章引用：张飞翔, 王建, 田星原, 孙海杰. 不同晶体结构的La0.9Sr0.1Ga0.8Mg0.2O3-δ体系氧空位的形成和迁移研究[J]. 化学工程与技术, 2020, 10(4): 322-328. https://doi.org/10.12677/HJCET.2020.104041

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