在Na4Fe3中实现快速和稳定的储存 (PO4) 2(P2O7) 通过热工程
Ning Jiang1,2, Xinyu Wang1,2, Haoran Zhou1
1Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China.
Small (Weinheim an der Bergstrasse, Germany)
|January 18, 2024
概括
高置换通过提高导电性和离子扩散来提高离子电池阴极性能. 在Na4Fe3(PO4)2(P2O7) 材料中,这种新的方法导致了更高的速度能力和更长的循环寿命.
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:
- Na4Fe3(PO4)2(P2O7) (NFPP) 是离子电池 (SIB) 的一个有前途的阴极材料,因为它的环保性和可负担性.
- 由于内在的低电子导电性和缓慢的离子扩散,NFPP的实际应用受到阻碍.
研究的目的:
- 通过使用高替代策略来解决NFPP的局限性.
- 为了提高基于NFPP的SIB的阴极材料的电化学性能,特别是导电性和离子扩散.
主要方法:
- 在NFPP结构中应用了高替代.
- 现场X射线衍射 (XRD) 用于分析化/脱过程中的结构变化.
- 进行了动力分析和密度函数理论 (DFT) 计算,以了解电子结构和离子扩散.
主要成果:
- 高性NFPP (HE-NFPP) 呈现出单相电化学反应,体积变化最小 (1.83%).
- 由于轨道混合协同作用,DFT的计算和动力分析证实了更好的电荷转移动力学和优化的离子扩散通道.
- 该HE-NFPP阴极表现出极好的速率性能 (55mAhg-1在10Ag-1) 和超长周期稳定性 (>18,000周期在5Ag-1).
- 使用HE-NFPP//硬碳 (HC) 的完整细胞在1000个循环中显示出良好的循环耐用性.
结论:
- 高工程是一种有效的策略,可以克服NFPP阴极材料的电化学限制.
- 开发的HE-NFPP为高性能离子电池提供了可行的途径,为未来的SIB材料开发提供了蓝图.
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