离子间隔到二维过渡金属碳化物:全球选新的高容量电池材料
Christopher Eames1, M Saiful Islam
1Department of Chemistry, University of Bath , Bath BA2 7AY, United Kingdom.
Journal of the American Chemical Society
|October 14, 2014
概括
这项研究选了MXenes用于电池应用,发现具有氧终结的轻过渡金属化合物为Li+和Mg2+离子提供了高容量. 这些MXenes显示了先进的可充电电池的前景.
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:
- 二维过渡金属碳化物 (MXenes) 是具有独特特性的新型材料.
- 由于其离子间能力,MXenes显示出作为可充电电池的电极材料的潜力.
研究的目的:
- 选一系列基于M2C的MXenes,以检测它们的间隙离子 (Li+,Na+,K+,Mg2+).
- 用密度函数理论来评估重力测量容量和电压.
- 为电池应用确定有前途的MXene组合物和表面终端.
主要方法:
- 全球计算选使用密度函数理论.
- 对基于M2C的化合物的分析 (M = Sc, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta).
- 对F,H,O和OH功能化表面的研究.
主要成果:
- 由于离子大小,Li+和Mg2+具有比Na+和K+更高的重力测量能力.
- 表面功能化和过渡金属选择显著影响MXene电压和容量.
- 氧气终结产生了最高的容量.
结论:
- 具有非功能化或O终端表面的轻过渡金属M2C化合物 (Sc,Ti,V,Cr) 是有前途的阳极材料.
- 这些MXenes表现出高的重力度容量 (>400 mAh/g).
- 为未来电池技术开发高容量MXenes提供了见解.
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