增强酸性伏尔默反应动力学的单原子电催化剂
Hao Cao, Qilun Wang1, Zisheng Zhang2
1School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637459, Singapore.
Journal of the American Chemical Society
|June 7, 2023
概括
设计有效的电催化剂是清洁能源的关键. 这项研究揭示了水界相互作用,而不仅仅是吸附能量,阻碍了单原子催化剂的性能,提出了一个新的设计原则.
科学领域:
- 材料科学
- 电化学
- 计算化学
背景情况:
- 开发用于演化反应 (HER) 的活性和低成本电催化剂对于清洁能源基础设施至关重要.
- 基于萨巴蒂尔原理的火山活动图表指导了贵金属和金属合金催化剂的设计.
- 由于单个金属原子位点的独特性质,将火山图形应用于添加石墨烯 (TM/N4C) 的单原子电催化剂 (SAE) 取得了有限的成功.
研究的目的:
- 在设计单原子电催化剂 (SAE) 进行演化反应 (HER) 时,研究传统火山图的局限性.
- 阐明影响SAE运动性能的潜在机制,包括界面相互作用.
- 提出一个新的,统一的SAE设计原则,包括热力学和动力学因素,以提高能转换.
主要方法:
- 使用ab initio分子动力学模拟和自由能量计算来研究各种SAE (TM/N4C,其中TM代表3d,4d或5d金属).
- 分析了介质和界面水分子之间的电荷双极相互作用对反应动学的影响.
- 进行实验电化学测量以验证关于运动阻碍的计算结果.
主要成果:
- 确定负电荷的*H中间体和界面H2O分子之间的强电荷双极相互作用是重要因素.
- 证明这些相互作用可以显著增加酸性伏尔默反应的动力障碍,尽管有利的吸附自由能量.
- 通过实验电化学测量证实了这种动力障碍的存在.
结论:
- 传统的火山图形不足以设计HER的高性能SAE,因为它忽略了界面动力效应.
- 水分子间的相互作用在SAE的催化活性中起着关键作用.
- 建议将热力学 (吸附能量) 和动力学 (界面相互作用) 考虑在内的新设计原则用于工程高级SAE的能转换.
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