用于带有轴性联体的单原子催化剂的一般描述器
Zelong Qiao1, Run Jiang1, Haoxiang Xu1
1State Key Laboratory of Organic-Inorganic Composites, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
Angewandte Chemie (International ed. in English)
|May 21, 2024
概括
轴协调配体 (ACL) 通过改变金属原子吸附和d轨道分散来调整单原子催化剂 (SAC). 一个新的描述符,σ,量化了结构-活性关系,有助于发现关键电化学反应的高活性SAC.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 计算化学的计算化学
背景情况:
- 单原子催化剂 (SAC) 对于各种化学反应至关重要.
- 调SAC活动通常涉及到用轴协调带 (ACL) 装饰活性金属部位.
- 通过ACL调节SAC性能的精确机制仍然不完全理解.
研究的目的:
- 研究SACs上的ACLs的调控机制.
- 开发一个一般描述器来量化ACL-SACs的结构-活动关系.
- 为了识别用于电催化应用的新型,高活性ACL-SAC.
主要方法:
- 多种ACL-SAC组合的计算选,涉及3d-5d过渡金属和十个原型ACL.
- 分析电子结构的变化,包括M-O结合能量水平和d-轨道分散.
- 开发和应用一个一般结构描述器 (σ) 和一个轴联体描述器 (σACL).
主要成果:
- 通过提高M-O键能量水平,ACLs削弱金属原子吸附,并增强d轨道分散.
- 基于内在特征构建了一个一般结构描述符 (σ),以量化ACL-SAC结构-活动关系.
- 轴联体描述符 (ACL) 显示了在实验环境中识别速度限制步骤的潜力.
- 预测的ACL-SACs (例如,与基准相比,CrN4,FeN4,CoN4,RuN4,RhN4,OsN4,IrN4,和PtN4-ACLs) 对氧气减少和进化反应表现出更高的活性.
结论:
- 通过电子结构调制,ACLs显著影响SAC性能.
- 开发的描述符 σ 提供了一种简单且具有成本效益的方法来评估高效的电催化剂.
- 已识别的ACL-SAC为氧气电催化剂的当前基准催化剂提供了有希望的替代品.
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