芳香基作为对高性能离子电池的阴极的温和预试剂
Shihao Zhang1, Jing Wang1, Kean Chen1
1College of Chemistry and Molecular Sciences, Hubei Key Laboratory of Electrochemical Power Sources, Wuhan University, Wuhan, 430072, China.
Angewandte Chemie (International ed. in English)
|January 22, 2024
概括
新的芳基 (AKs) 作为离子电池的温和化学预化试剂. 这些试剂提高了阴极容量和电池性能,而不会造成过度或结构损坏.
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:
- 化学前化 (CP) 提高了离子电池的能量密度.
- 现有的多环芳 (PAH) 试剂具有较低的还原潜力,导致过度和阴极降解.
研究的目的:
- 设计和评估芳香 (AKs) 作为温和的化学预试剂.
- 通过引入碳基组来平衡PAHs中的结合和诱导作用.
- 为了提高离子电池阴极的初始充电能力和稳定性.
主要方法:
- 通过将碳基组纳入PAHs来合理设计芳香 (AKs).
- 合成和表征9-氨 (9-FN) 和氨 (BP) 作为代表性的AKs.
- 使用各种离子阴极材料 (Na$_{0.44}$MnO$_{2}$,Na$_{0.67}$Ni$_{0.33}$Mn$_{0.67}$O$_{2}$,Na$_{4}$Fe$_{2.91}$(PO$_{4}$) 测试9-FN的预能力,Na$_{3}$V$_{2}$(PO$_{4}$,Na$_{3}$,Na$_{3}$V$_{2}$) 进行了测试.
主要成果:
- 9-FN和BP表现出有利的平衡潜力 (分别为1.55V和1.07V与Na$^{+}$/Na).
- 9-FN在多个阴极宿主中展示了多功能预化能力.
- 观察到,前性阴极的初始充电能力得到了显著改善,平衡了阳极不可逆转的容量.
结论:
- 芳香是高性能离子电池的有效和具有竞争力的轻度预化试剂.
- 开发的AK减轻了与传统PAH试剂相关的过度和结构恶化问题.
- 这项工作为开发用于离子电池的先进阴极材料提供了新的途径.
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