通过将氧气纳入高性能Li-S电池表面来调节COP的电化学动力学
Rui Sun1,2, Meixiu Qu1,2, Lin Peng1,2
1Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing, 100081, P. R. China.
Small (Weinheim an der Bergstrasse, Germany)
|June 9, 2023
概括
化 (CoP) 电催化剂的表面氧含量通过改善聚硫化 (LiPS) 的吸附和转化来提高硫 (Li-S) 电池的性能,克服了关键的限制.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 硫 (Li-S) 电池具有高的理论能量密度,但面临着诸如多硫化物 (LiPSs) 的穿效应和缓慢的氧化还原动力学等挑战.
- 电催化剂的表面性能对于吸附和转化LiPS至关重要,因此表面工程是提高Li-S电池性能的关键策略.
研究的目的:
- 为了研究表面氧含量对嵌入化 (CoP) 纳米颗粒的表面氧含量的影响,化 (C/O-CoP) 嵌入空碳纳米中,用于Li-S电池应用.
- 探索COP表面氧气修饰如何影响LiPS吸附和氧化还原转化动力学.
主要方法:
- 合成具有不同表面氧含量的C/O-CoP纳米粒子.
- 用合成的C/O-CoP材料对分离器的功能化.
- 改造的Li-S电池的电化学性能测试.
- 密度函数理论 (DFT) 计算以阐明增强机制.
主要成果:
- 在CoP上增加表面氧含量显著增强LiPS的化学吸附,并加速它们的氧化还原转化.
- 使用C/O-CoP修改分离器的Li-S电池初始容量为1033 mAh g−1 ,在2C的200个循环后保持749 mAh g−1 .
- DFT的计算证实了表面氧在Li-S电化学反应中的有益作用.
结论:
- CoP电催化剂的表面氧化工程是一种有效的策略,可以减轻穿效应并提高Li-S电池的电化学性能.
- 这项研究为基于COP的Li-S电池系统中氧气作用的机制提供了基本的见解.
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