Na2-xLixFePO4F/C复合阴极材料的制备和电化学性能,具有不同的/比
Lei Wang1,2, Hualing Tian1,2, Xiang Yao1,2
1College of Chemistry and Chemical Engineering, Xinjiang Normal University, Urumqi 830054, China.
Micromachines
|January 26, 2024
概括
研究人员通过加入离子来增强铁化 (NFPF) 阴极材料用于离子电池. 这种修改显著提高了电化学性能,为更高效的储能解决方案铺平了道路.
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:
- 离子电池 (SIB) 由于具有成本效益和安全的材料,正在获得引力.
- 铁酸 (Na2FePO4F,NFPF) 作为SIBs的阴极材料具有前景,具有高的理论容量和电压.
- 目前NFPF的局限性包括电子导电性差和离子扩散缓慢,阻碍实际应用.
研究的目的:
- 研究NFPF阴极材料中用离子替换离子的影响.
- 优化Na2-xLixFePO4F/C的组成,以提高SIB中的电化学性能.
- 分析修改后的NFPF材料的结构和纳米结构特性.
主要方法:
- 高温固体相合成技术以产生Na2-xLixFePO4F/C (0 ≤ x ≤ 2).
- 电化学测试用于评估电荷-放电性能,容量保留和库伦效率.
- 使用传输电子显微镜 (TEM) 和X射线衍射 (XRD) 分析晶体结构和纳米结构的材料表征.
主要成果:
- 在室温下以x = 0.5 (Na1.5Li0.5FePO4F/C) 实现了最佳性能.
- Na1.5Li0.5FePO4F/C 阴极表现出高的初始放电特异容量,在0.1°C时为122.9 mAh g-1.
- 经过100个循环,该材料保留了118 mAh g-1 (96.2%的容量保留) 与98%的库伦效率.
结论:
- 在NFPF中用Li+部分替代Na+,显著提高了电化学性能.
- 该Na1.5Li0.5FePO4F/C材料显示出作为SIBs的高性能阴极的绝佳潜力.
- 结合和离子是一种有效的策略,可以提高用于储能应用的电极材料的性能.
相关概念视频
Ladder Diagrams: Redox Equilibria
458
Ladder diagrams are useful tools for understanding redox equilibrium reactions, especially the effects of concentration changes on the electrochemical potential of the reaction. The vertical axis in the redox ladder diagrams represents the electrochemical potential, E. The area of predominance is demarcated using the Nernst equation.
Consider the Fe3+/Fe2+ half-reaction, which has a standard-state potential of +0.771 V. At potentials more positive than +0.771 V, Fe3+ predominates, whereas Fe2+...
Consider the Fe3+/Fe2+ half-reaction, which has a standard-state potential of +0.771 V. At potentials more positive than +0.771 V, Fe3+ predominates, whereas Fe2+...
458
Electrodeposition
634
Electrodeposition is a technique used to separate an analyte from interferents by electrochemical processes. Here, the analyte is a metal ion that can be deposited on an electrode immersed in the sample solution. The electrochemical setup consists of an anode and a cathode. When an electric current is applied to the setup, oxidation occurs at the anode. At the cathode, which consists of a large metal surface, metal ions undergo reduction and deposit onto the surface.
Electrodeposition can...
Electrodeposition can...
634
Batteries and Fuel Cells
27.4K
A battery is a galvanic cell that is used as a source of electrical power for specific applications. Modern batteries exist in a multitude of forms to accommodate various applications, from tiny button batteries such as those that power wristwatches to the very large batteries used to supply backup energy to municipal power grids. Some batteries are designed for single-use applications and cannot be recharged (primary cells), while others are based on conveniently reversible cell reactions that...
27.4K


