In situ observation of the deterioration process of sulfide-based solid electrolytes using airtight and air-flow TEM systems
In situ observation of the deterioration process of sulfide-based solid electrolytes using airtight and air-flow TEM systems
复制标题
使用密闭和气流 TEM 系统原位观察硫化物基固体电解质的劣化过程
DOI：
10.1093/jmicro/dfab022
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发表时间：
2021
期刊：
影响因子：
1.8
通讯作者：
S. Mori
中科院分区：
文献类型：
--
作者：
H. Tsukasaki;K. Igarashi;A. Wakui;T. Yaguchi;H. Nakajima;T. Kimura;A. Sakuda;M. Tatsumisago;A. Hayashi;S. Mori
具有高离子电导率的硫化物基固体电解质是下一代全固态电池不可缺少的电池材料。然而，硫化物基se的主要缺点是在空气中的化学稳定性较低。当暴露于H2O或o2气体时，产生有毒的H2S，其离子电导率显著下降。然而，它们在暴露于空气中的降解机制尚不清楚。为了阐明降解过程，在本研究中，我们开发了一种透射电子显微镜（TEM）系统来评估电池材料的空气稳定性。利用真空传递双倾斜TEM固定器和气流系统，对硫化基li4sns4玻璃陶瓷在气流环境下的降解过程进行了现场观察。因此，电子衍射（ED）模式和透射电镜图像可以清楚地捕捉到空气暴露引起的形态变化和非晶化过程。此外，根据ED图分析，li4sns4在空气中与H2O发生反应，容易发生分解。因此，该密闭气流TEM系统应能有效阐明硫基se暴露于空气中的劣化过程。
Sulfide-based solid electrolytes (SEs) exhibiting high ionic conductivity are indispensable battery materials for next-generation all-solid-state batteries. However, sulfide-based SEs have a major drawback in their low chemical stability in air. When exposed to H2O or O2gas, toxic H2S is generated, and their ionic conductivity considerably declines. However, their degradation mechanism caused by air exposure has not been understood yet. To clarify the degradation process, in this study, we developed a transmission electron microscope (TEM) system to evaluate the air stability of battery materials. Using a vacuum transfer double-tilt TEM holder with a gas-flow system, thein situobservation of the degradation process was conducted for a sulfide-based Li4SnS4glass ceramic under an air-flow environment. Consequently, electron diffraction (ED) patterns and TEM images could clearly capture morphological changes and the amorphization process caused by air exposure. Moreover, based on the analysis of ED patterns, it is observed that Li4SnS4is likely to decompose because of the reaction with H2O in air. Therefore, this airtight and air-flow TEM system should be effective in clarifying the process of the deterioration of sulfur-based SEs during exposure to air.