机械互锁增强了分子铜复合物的电催化氧降低活性和选择性
Xiaoyong Mo1, Yulin Deng1, Samuel Kin-Man Lai1
1Department of Chemistry, HKU-CAS Joint Laboratory of New Materials, University of Hong Kong, Hong Kong, China.
Journal of the American Chemical Society
|February 28, 2023
概括
机械互锁的铜联体增强氧降解反应 (ORR) 催化. 这一突破提高了水生成的选择性,并改善了催化剂的活性,为催化剂提供了有希望的替代品.
科学领域:
- 电化学和催化
- 材料科学
- 超分子化学
背景情况:
- 有效的氧降解反应 (ORR) 对于先进的燃料电池技术至关重要.
- 寻求非贵金属催化剂,特别是铜复合物,以替代昂贵的基材料.
- 目前由酶启发的铜复合体缺乏所需的ORR催化性能.
研究的目的:
- 将机械互锁引入铜协调位点的联体架构.
- 调查相互锁定的连锁体如何影响ORR活动和选择性.
- 为了提高ORR的铜基电催化剂的性能.
主要方法:
- 机械互锁铜复合物的合成和表征.
- 合成的复合物的氧降解反应 (ORR) 的电化学评估.
- 综合实验和理论研究以阐明反应机制.
主要成果:
- 通过链结构的连接将ORR选择性通过4e-通路引导到H2O,与相竞争.
- 与非互锁对应物相比,铜连锁复合体的启动电位增加了130mV.
- 大众活动和周转频率分别增长了1.8倍和1.5倍.
结论:
- 连接体设计中的机械互锁是提高电催化剂性能的一种有效策略.
- 开发的铜复合体表现出优异的ORR活性和选择性.
- 这些发现为涉及质子-合电子转移的氧化还原反应提供了宝贵的机理见解.
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