通过外源和内源动态核极化检测的Na-Ion阳极上的固体电解质间相的组成和结构─NMR光谱
Yuval Steinberg1, Elias Sebti2,3, Ilia B Moroz1
1Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 761000, Israel.
Journal of the American Chemical Society
|August 22, 2024
概括
动态核极化 (DNP) 增强的固态核磁共振光谱为离子电池 (SIB) 的固体电解质介面 (SEI) 提供了前所未有的洞察力. 这种方法绘制了SEI的组成和空间分布,这对于提高SIB的性能至关重要.
科学领域:
- 材料科学
- 电化学
- 光谱学
背景情况:
- 离子电池 (SIB) 对大规模储能具有前景.
- 稳定的SIB性能依赖于阳极的固体电解质间相 (SEI).
- 由于SEI的异质性和少量性质,其表征具有挑战性.
研究的目的:
- 开发和应用一种敏感的SEI分析方法.
- 研究SIB中的Li4Ti5O12阳极的SEI组成和空间分布.
- 了解电解质添加剂对SEI特性和SIB性能的影响.
主要方法:
- 固态核磁共振 (NMR) 光谱学
- 使用外源和内源的动态核极化 (DNP) 增强.
- 在离子电池中的Li4Ti5O12阳极上形成的SEI分析.
主要成果:
- 完成了SEI阶段的详细组成映射和空间分布.
- 在SEI中发现了从有机到无机阶段的组成梯度.
- 乙烯碳酸盐添加剂导致SEI较厚,富含NaF和碳酸盐,与性能降低相关.
结论:
- 用DNP增强的固态NMR是SEI调查的强大工具.
- 了解SEI的结构和组成是优化SIB的关键.
- 该方法可扩展到其他阳极材料和电解质,用于SIB开发.
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