通过获得反应中间体的全球稳定结构来准确评估氧电池的性能
Yan Wang, Xiaojuan Hu, Zhiyu Wang1
1School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
The journal of physical chemistry letters
|July 28, 2025
概括
单原子催化剂可以提高非水性氧电池的效率. 这项研究使用计算方法找到最佳的催化剂结构,揭示了Co-N4C在性能和稳定性方面优越.
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
- 计算化学的计算化学
背景情况:
- 单原子催化剂 (SAC) 对非水性氧 (Li-O2) 电池具有前景.
- 不一致的性能评估源于复杂的排放产品配置.
研究的目的:
- 制定一个严格的框架,准确评估Li-O2电池的电催化性能.
- 为了确定 SAC 上的 Li-O2 排放产品的真实地面状态配置.
- 在催化剂性能预测中克服手动结构选择的偏差.
主要方法:
- 将第一原则计算与全球结构搜索差异演变算法的集成.
- 在过渡金属和密封石墨烯 (TM-N4C) 上选了超过1500种LiOx排放产品的吸附几何形状.
- 自由能量分析以确定催化剂活性和速度限制步骤.
主要成果:
- 确定了LiOx物种的真实基态配置,显示出比以前使用的模型更大的热力学稳定性.
- 揭示了对有限几何学的依赖可能导致错误的性能预测.
- 突出显示Co-N4C作为具有超低超电位的最佳催化剂 (ORR为0.17V,OER为0.10V).
结论:
- 由于吸附能量的平衡,Co-N4C表现出特殊的活性,促进排放产品的均沉积和高效的脱吸.
- 2O2的形成和 (2O2) 2的分解被确定为速度限制的步骤.
- 这项工作建立了一个强大的计算框架,用于准确评估Li-O2电池中的SAC.
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