通过用于储能应用的二元混合策略来缓解受限诱导的介电常数减少
Yiyue He1, Zemeng Feng1, Zhaogang Peng1
1State Key Laboratory of Flexible Electronics (LoFE) & Institute of Advanced Materials (IAM), School of Flexible Electronics (Future Technologies), Nanjing Tech University (NanjingTech), Nanjing 211816, China.
The Journal of chemical physics
|May 16, 2025
概括
封闭降低了超级电容器中的电解质介电常数. 二元溶剂混合减轻了这一点,提高了性能和离子扩散,以更好地储存能量.
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
- 计算化学计算化学
背景情况:
- 电解质的介电常数对于超级电容器的性能至关重要.
- 纳米级封闭显著降低了电解质介电常数,影响了固体-液体接口的能量储存.
- 对于基于MXene的超级电容器来说,了解这些效应至关重要.
研究的目的:
- 通过分子动力学模拟,研究受限下有机溶剂的介电常数减少.
- 分析封闭对乙烯碳酸盐 (EC) 电解质性能的影响.
- 提出并评估二元溶剂混合策略,以减轻介电常数减小和提高超级电容器性能.
主要方法:
- 用分子动力学模拟来研究纳米级限制下的电解质行为.
- 分析的重点是电荷密度分布和乙烯碳酸盐 (EC) 内的局部极化相关性.
- 开发并模拟了一种二进制混合策略,以优化电解质特性.
主要成果:
- 纳米孔 (<10 nm) 中的封闭导致了像EC这样的有机电解质的介电常数显著下降.
- 这种减少归因于电荷密度分布的改变和接近表面的增强局部极化相关性.
- 一种二元溶剂混合物有效地平衡了局部和全球极化,减轻了介电常数的减少.
- 优化混合物显示离子扩散系数比纯EC增加了四倍.
结论:
- 纳米级封闭显著影响电解质介电性质,给超级电容器设计带来了挑战.
- 二元溶剂混合策略提供了一种可行的解决方案,以保持和提高电解质在限制条件下的性能.
- 这种方法为在封闭的环境中设计高性能超级电容器的先进电解质提供了途径.
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