不对称的协调单原子催化剂为高性能Li-S电池提供零级的硫氧化还原动力学
Xianghua Kong1, Yifan Li2, Guolei Cai3
1Anhui Province Key Laboratory of Value-Added Catalytic Conversion and Reaction Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei, 230009, China.
Angewandte Chemie (International ed. in English)
|July 23, 2025
概括
具有Ni-N3P1协调的不对称单原子催化剂 (SAC) 通过改变硫氧化还原动力学,显著提高硫电池性能. 这一突破使下一代电池能够实现更高的能量密度和更好的循环稳定性.
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
- 催化剂是一种催化剂.
背景情况:
- 在硫 (Li-S) 电池中实现高能量密度需要克服缓慢的硫氧化还原动力学.
- 具有对称M-N4协调的单原子催化剂 (SAC) 是有前途的,但在加速这些反应方面存在局限性.
研究的目的:
- 研究单原子催化剂中不对称协调对Li-S电池中硫氧化还原反应 (SRR) 动力学的影响.
- 探索SAC中的对称性破坏如何改变反应途径并改善聚硫化物转化.
主要方法:
- 实验和理论研究使用基于Ni原子的SAC与不对称的Ni-N3P1协调 (Ni-NPG).
- 分析硫氧化还原反应动力学,从一阶转向零阶行为.
- 研究聚硫化物吸附和转化途径.
主要成果:
- 不对称的协调从根本上改变了SRR动力学到零级,增强了聚硫化物转换.
- 对称性破坏提高了Ni d带中心,促进Li2S4吸附,有利于液体-固体转换.
- 使用Ni-NPG的Li-S电池在4C时达到877mAhg-1的特定容量,在0.2C的200个循环后保持92%的容量.
结论:
- 在SAC中不对称的协调提供了一种新的策略,以克服Li-S电池的动力限制.
- 与对称SAC相比,Ni-N3P1协调的SAC表现出优越的性能,为高能量密度Li-S电池铺平了道路.
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