过渡阶段介导的+运输在兰泰坦酸固态电解质中
Yuxin Qiu1, Yao Nian2, Yonghui Ma3
1Institute of Molecular Plus, Department of Chemistry, Tianjin University & Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300072, China.
ACS applied materials & interfaces
|September 28, 2024
概括
lanthanum titanium oxide (LLTO) 固体电解质对电池来说非常有前景. 一个短暂的 (La,Ti) 2O3 阶段阻碍了离子扩散,影响电导率.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 电化学 电化学 电化学
背景情况:
- lanthanum titanium oxide (LLTO) 是电池的一个有前途的固态电解质.
- 在LLTO中了解离子扩散机制对于提高电池性能至关重要.
- 结构缺陷和杂质相对LLTO的离子导电性有很大的影响.
研究的目的:
- 在LLTO中研究原子规模的离子扩散机制.
- 描述LLTO陶颗粒中存在的结构缺陷和过渡阶段.
- 为了将这些相的形成与烧结过程以及它们对离子导电性的影响相关联.
主要方法:
- 偏差校正传输电子显微镜 (TEM) 用于详细的结构特征.
- 晶体分析用于研究相位过渡和方向.
- 扩散的原子化机制的理论评估.
主要成果:
- 在LLTO域内的反相边界确定了一个普遍的短暂 (La,Ti) 2O3相.
- 这一过渡阶段呈现出逐渐的结构过渡到四边形LLTO结构.
- 扩散被短暂阶段减缓,与过量的 (La) 相对应.
结论:
- 过渡 (La,Ti) 2O3 阶段在 LLTO 的离子导电性中起着重要作用.
- 在烧结过程中控制这种相的形成是优化LLTO电解质的关键.
- 过多的La含量加剧了短暂阶段引起的扩散障碍.
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