在电化学脉冲CO2降低过程中指导反应中间体和催化剂表面的动态,以提高C2+的选择性
Zhuofeng Li1,2,3, Linqin Wang1,2,3, Tao Wang1,2,3
1Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, Hangzhou 310024, Zhejiang, China.
Journal of the American Chemical Society
|August 28, 2023
概括
脉冲电解通过动态控制氧化铜/铜表面成分,提高了对多碳产品的二氧化碳减排选择性. 这种方法提供了一种除了减少二氧化碳之外的电催化改进的总体策略.
科学领域:
- 电催化
- 表面化学
- 光谱学
背景情况:
- 开发先进的电解技术对于电催化非常重要.
- 脉冲电化学二氧化碳还原反应 (CO2RR) 显示,与静电方法相比,对多碳产品的选择性有所改善,但机制尚不清楚.
研究的目的:
- 研究脉冲CO2RR中改善的C2+选择性的机制.
- 了解脉冲电解中的表面成分和中间体的作用.
主要方法:
- 开发了一种快速时间分辨率0.25秒的现场拉曼光谱法.
- 在脉冲电解过程中分析的表面Cu_xO/Cu组成动态.
- 表面吸附的二氧化碳中间体及其振动模式.
主要成果:
- 脉冲电解可以动态控制表面Cu_xO/Cu组成,增强C2+的选择性.
- COads的数量是决定脉冲CO2RR中的C2+/C1选择性的关键因素.
- 碳化合物的振动性不是主要的选择性决定因素.
结论:
- 脉冲电解提供了对催化剂表面和中间体的动态控制,改善了CO2RR的性能.
- 这种方法为增强CO2RR以外的各种反应中的电催化提供了总体策略.
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