从氧化还原到硫化还原:丰富层级阴极的范例
Jing-Chang Li1,2, Jiayi Tang1, Jiaming Tian1,2
1College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, National Laboratory of Solid State Microstructures, Collaborative Innovation Centre of Advanced Microstructures, Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, Nanjing 210093, P. R. China.
Journal of the American Chemical Society
|February 20, 2024
概括
硫基主机通过稳定分层结构显著提高离子电池的能量密度. 这种方法克服了基于氧的材料的局限性,使离子氧化还原化学能够改善电池性能.
科学领域:
- 材料科学
- 电化学
- 电池技术
背景情况:
- 丰富的氧化物中的离子氧化还原化学为离子电池提供了更高的能量密度.
- 基于氧的宿主因TM-O键的离子性而面临结构重组和过渡金属 (TM) 离子迁移等挑战.
研究的目的:
- 提出并验证一种基于硫的宿主作为稳定丰富阴极框架的内在解决方案.
- 研究硫氧化还原过程中的晶格扭曲的缓冲,并改善结构完整性.
主要方法:
- 使用具有强TM-S共价性的硫基宿主来增强框架稳定性.
- 进行富硫化物阴极的实验循环.
- 使用高维神经网络潜力进行大规模分子动力学模拟以分析离子轨迹.
主要成果:
- 在+提取/插入过程中,已证明硫层格子,包括蜂超格子的长时间保存.
- 在丰富的硫化物阴极中实现了优异的电化学性能,电压过大 (0.08 V) 和电压下降最小 (0.13 mV/周期).
- 在模拟过程中,与氧相比,硫离子轨迹显著较短.
结论:
- 基于硫的宿主有效地稳定了宿主框架,克服了基于氧的材料出现的问题.
- 强大的TM-S共价和较短的离子扩散途径有助于优越的电化学性能和耐用性.
- 突出了稳定框架对于持久的离子氧化还原化学的重要性,并为设计先进的丰富阴极提供了指导.
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