具有增强的离子导电性的可拓变形抗相边界
Kun Xu1,2, Shih-Wei Hung3,4, Wenlong Si5,6
1National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, PR China. kunxuem@stanford.edu.
Nature communications
|November 15, 2023
概括
工程晶格缺陷,特别是可顶点变形的反相边界 (tt-APB),在混合离子电子导体 (MIEC) 中增强离子导电性. 这些tt-APB充当关键的离子扩散通道,改善固体氧化物燃料电池的性能.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 纳米技术纳米技术
背景情况:
- 格子缺陷是为了调整设备功能而设计的.
- 混合离子电子导体 (MIEC) 中的反相边界 (APB) 传统上阻碍了固体氧化物燃料电池的离子导电性.
- 了解缺陷行为是优化能源设备的关键.
研究的目的:
- 在原子层面上识别和描述可拓变形抗相边界 (tt-APBs).
- 与完美域相比,研究这些tt-APB的离子导电性.
- 阐明在TT-APB中氧气迁移的机制.
主要方法:
- 使用先进显微镜进行原子级缺陷识别.
- 在现场观察动态氧气迁移.
- 在受控大气层中进行火实验.
主要成果:
- 在高温下,地形变形APB (tt-APB) 的离子导电率高于无缺陷域.
- 在TT-APB中观察到动态氧气迁移,由间歇性位点促进.
- 在氧化条件下火促进了tt-APB的间歇氧气形成,增强了导电性.
结论:
- tt-APB的功能是有效的离子扩散通道,对氧导电性有显著的贡献.
- 拓变形性是决定APB在离子运输中的作用的关键因素.
- 通过TT-APB的缺陷工程提供了一个有前途的策略,用于增强MIEC的离子运输,用于能源应用.
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