通过高性能硫电池的原子分散异核Fe-Co对来平衡电子旋转状态
Canhuang Li1,2,3, Jing Yu2,4, Dawei Yang1
1Henan Key Laboratory of Quantum Materials and Quantum Energy, School of Quantum Information Future Technology, Henan University, Kaifeng 475004, China.
Journal of the American Chemical Society
|February 28, 2025
概括
这项研究引入了一个新的铁二原子催化剂,用于室温硫电池的碳纳米圈. 这种催化剂有效地抑制了聚硫化物转运,并增强了硫氧化还原动力学,提高了电池性能.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- 室温-硫 (Na-S) 电池具有高能量密度和低成本,但受到聚硫化物穿和缓慢反应动力的影响.
- 开发高效的催化剂对于克服Na-S电池阴极的这些局限性至关重要.
研究的目的:
- 设计和研究一个异核二原子催化剂 (Fe-Co/NC) 以提高Na-S电池的性能.
- 阐明Fe-Co双金属位点在加速硫氧化还原反应中的催化机制.
主要方法:
- 含的空心碳纳米球与嵌入的Fe-Co双金属位点 (Fe-Co/NC) 的合成.
- 使用异常纠正的HAADF-STEM和同步辐射XAS进行表征.
- 使用密度函数理论 (DFT) 的计算分析.
主要成果:
- 证实了具有 (Fe-Co-N6) 协调结构的孤立Fe-Co原子对的存在.
- DFT计算显示Fe诱导的电子移位在Co2中,促进杂交并加速硫转化.
- Fe-Co/NC 阴极表现出良好的循环稳定性 (2000 个循环后为 378 mAh g-1) 和速率能力 (341.1 mAh g-1 在 5 A g-1 时).
结论:
- Fe-Co/NC 作为有效的硫宿主,减轻了 Na-S 电池的穿效应并增强了其动力.
- 异核二原子催化剂设计为下一代高性能硫电池提供了有希望的策略.
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