调节空位和局部协调结构 实现稳定的基于的NASICON阴极
Nan Zhang1,2, Han Zhang1,2, Jiaxuan Liu1,2
1State Key Laboratory of Space Power-Sources, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China.
Angewandte Chemie (International ed. in English)
|November 26, 2025
概括
铁兴奋剂通过减少缺陷和减轻结构扭曲来稳定离子电池的Na3MnTi(PO4) 3阴极. 这提高了性能,为高能耗,持久的电池提供了有前途的途径.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 储能 储能 储能 储能 储能 储能
背景情况:
- 纳西康型Na3MnTi(PO4) 3 (NMTP) 阴极为离子电池提供低成本和高容量.
- 电压歇斯底里和结构降解限制NMTP阴极性能.
研究的目的:
- 通过空位和局部协调合策略,增强NMTP阴极稳定性和电化学性能.
- 通过低价值离子兴奋剂来抑制内在抗体缺陷 (IASD) 和Jahn-Teller扭曲.
主要方法:
- 在NMTP网格中引入了Fe2+兴奋剂,产生了Na3+2xMnTi1-xFex(PO4)3.3.
- 使用DFT计算,现场XANES和ssNMR分析来研究协同机制.
- 评估电化学性能,包括特定容量,速率能力和循环稳定性.
主要成果:
- 2+兴奋剂降低了Na空位度,并激活了Na2位点,抑制了IASDs.
- 重建的Mn-O协调增强了MnO6对称性,减轻了Jahn-Teller扭曲.
- 优化Na3.2MnTi0.9Fe0.1(PO4)3表现出高容量 (174.2mAhg-1在0.1°C),优异的速率能力 (125.5mAhg-1在20°C),和稳定的循环 (85%的保留2000个循环后).
结论:
- 减少空隙度和稳定MnO6对称性的协同机制有效地抑制电压歇斯底里和Jahn-Teller扭曲.
- 2+兴奋剂为设计高能量密度,寿命长的离子电池提供了可行的策略.
- 这项工作为先进电池材料的空缺和协调工程提供了洞察力.
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