电离子决定性氧降解反应在Pt上的机制和选择性{111}
Tomoaki Kumeda1, Laura Laverdure2, Karoliina Honkala2
1Research Center for Energy and Environmental Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki, 305-0044, Japan.
Angewandte Chemie (International ed. in English)
|November 20, 2023
概括
电离子通过改变电极层和质子合电子转移 (PCET) 路径,影响表面的氧降解反应 (ORR) 机制. 这一发现影响了电化学系统设计和催化剂选.
科学领域:
- 电触媒溶解是一种电触媒.
- 表面化学 表面化学
- 物理化学 物理化学
背景情况:
- 氧降解反应 (ORR) 的质子合电子转移 (PCET) 机制仍然不太清楚,特别是在表面的电解质和pH影响方面.
- 在Pt(111) 上控制ORR-PCET的因素尚未解决,阻碍了电催化应用的进步.
研究的目的:
- 通过综合实验和计算方法阐明在性ORR机制中的的作用.
- 了解阴离子效应如何影响表面活性部位和PCET通路.
主要方法:
- 集成先进的实验技术,理论模拟和基本理论.
- 在性介质中对Pt{111}表面的阴离子效应的研究.
主要成果:
- 揭示了一种双离子效应,影响电极表面 (Pt-O/Pt-OH覆盖层) 和PCET步骤 (内部与外部球).
- 证明了 Pt-O 和 Pt-OH 之间的离子依赖过渡决定了 ORR 机制,活性和选择性.
- 提供了电解质对ORR性能影响的直接证据.
结论:
- 电离子通过调节表面物种和电子转移通路,在确定ORR机制和Pt上的表现方面发挥着关键作用.
- 这些发现需要在设计高效的电化学系统和计算催化剂选时考虑电解质组成.
- 强调了实验和模拟洞察力之间的协同作用,以了解复杂的电催化接口.
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