由于自旋状态的变化引起的电子转移作为C2N-TM单原子催化剂上的催化描述剂
Peng Liu1, Huifeng Liu1, Yue Qiu2
1School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong 273165, People's Republic of China.
The journal of physical chemistry letters
|August 26, 2024
概括
金属单原子催化剂中的旋转状态影响氧减少反应 (ORR). 电子自旋瞬间的变化驱动电子转移,增强2e-过氧化路径的催化活性.
科学领域:
- 不同质的催化剂.
- 材料科学 材料科学 材料科学
- 计算化学的计算化学
背景情况:
- 金属单原子催化剂 (SAC) 的性能严重依赖于它们的自旋状态.
- 旋转状态和催化活性/选择性之间的确切关系尚不清楚.
- 了解这些联系对于设计先进的催化剂至关重要.
研究的目的:
- 研究氧降解反应 (ORR) 的催化活性和选择性.
- 探索旋转状态在支持C2N的3D过渡金属SAC中的作用.
- 阐明控制ORR路径和催化效率的基本机制.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 该研究的重点是C2N支持的3D过渡金属 (Mn,Co,Ni,Cu) SAC.
- 分析包括对不同自旋状态和反应途径 (2e-H2O2与4e-OOH) 的评估.
主要成果:
- 大多数SAC倾向于2e-H2O2路径,除了C2N-Mn (S=1/2) 遵循4e-OOH路径.
- 金属中心和OOH中间体的电子旋转时刻变化的总和影响了电子传输.
- 电子转移显著促进了C2N-TM SACs上的2e-H2O2通路的催化活性.
结论:
- 在OOH电子转移和2e-H2O2通路的催化活性之间存在强烈的线性相关性.
- 由自旋状态变化引起的电子转移,作为C2N-TM SACs中的催化活性描述器.
- 这些发现为ORR高效SAC的合理设计提供了洞察力.
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