在蜂层Na2MgZn2-TeO6固体电解质中揭示离子动力学
Diganta Sarkar1, Amit Bhattacharya1, Jan Meyer2
1Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
Journal of the American Chemical Society
|August 29, 2023
概括
研究人员使用先进的磁共振探索了新的固态离子电池电解质. 他们发现一种具有可定制导电性的新材料, 对于更安全,更可持续的储能解决方案至关重要.
科学领域:
- 材料科学
- 固态化学
- 电化学
背景情况:
- 全固态离子电池 (SIB) 为大规模,安全和可持续的能量存储提供了有希望的替代品.
- 了解固体电解质中的原子尺度结构和离子动力学对于提高SIB性能至关重要.
研究的目的:
- 研究一种新的Mg/Zn混合离子蜂层氧化物,Na2MgxZn2-xTeO6,作为SIB的潜在固体电解质.
- 通过使用多核磁共振来阐明这些材料中的原子尺度结构,阴离子失调和 (Na) 离子动态.
主要方法:
- 多核磁共振 (23Na,125Te,25Mg,67Zn) 光谱学
- 粉末X射线衍射 (XRD),能量散射X射线 (EDX) 光谱和场辐射扫描电子显微镜 (FESEM).
- 电化学阻抗光谱 (EIS) 和密度函数理论 (DFT) 的计算.
主要成果:
- 合成了P6322空间组中的纯相晶体化合物,形成了Na2MgxZn2-xTeO6固体溶液系列.
- 在室温下达到0.14 × 10^-4 S cm^-1的最大值.
- 描述了Mg/Zn乱,揭示了蜂层和多个Na位点中的随机分布. 观察到快速的局部离子跳跃 (0.83 × 10^9 Hz),与Mg/ Zn障碍相关.
结论:
- 新型Na2MgxZn2-xTeO6固体溶液是SIB固体电解质的有希望的候选物.
- 多核磁共振是理解固体电解质结构与性质关系的强大工具.
- 优化Mg/Zn乱是提高这些材料中离子动态和导电性的关键.
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