在水性离子电池中增强伪容量的一种酸电解质
Zhuoheng Bao1, Chengjie Lu1, Qiang Liu1
1School of Materials Science and Engineering, Southeast University, Nanjing, 211189, P. R. China.
Nature communications
|March 2, 2024
概括
V2CTx MXene作为离子电池的阳极具有前景,提供高容量和稳定性. 乙离子通过促进可逆电子转移来增强储存,克服了以前的限制.
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
- 计算化学的计算化学
背景情况:
- 离子电池提供了具有成本效益,安全和环保的能源存储.
- 由于缺乏合适的阳极材料,发展受到阻碍.
研究的目的:
- 研究V2CTxMXene作为离子电池的潜在阳极.
- 探索离子储存的机制和乙酸离子的作用.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 在现场进行电化学石英晶微平衡 (EQCM) 测量.
- 在氨酸电解质中的实验验证.
主要成果:
- V2CTxMXene具有伪容量离子储存,容量为115.9mAhg-1在1Ag-1时.
- 观察到优异的容量保留 (100%在5 A g-1的5000个循环后).
- DFT透露了通过[NH4+(HAc) 3]···O协调键的可逆电子转移.
结论:
- V2CTx MXene是高性能离子电池的一个有前途的阳极材料.
- 乙离子增强显著增加了离子储存能力.
- 这一战略克服了法拉第式和非法拉第式能源存储的局限性.
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