用时间分辨率拉曼光谱测试铜电极的低超电位CO2到CO激活的动态
Jim de Ruiter1, Hongyu An1, Longfei Wu1
1Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
Journal of the American Chemical Society
|August 11, 2022
概括
时间分辨率光谱显示了CO2RR过程中氧化铜电极的重组情况. 脉冲电解通过动态表面变化在低电位上激活CO2,为高效的一氧化碳生产提供了洞察力.
科学领域:
- 电化学
- 材料科学
- 表面化学
背景情况:
- 氧化物衍生铜电极可以提高价值化学物质的CO2RR.
- 了解CO2RR过程中的电极重组至关重要,但不完整.
- 需要阐明动态重组与电极性能之间的相互作用.
研究的目的:
- 在CO2RR过程中研究铜 (氧化物) 电极的动态重组.
- 使用时间解析面增强拉曼光谱 (TR-SERS) 研究反应中间体的吸附.
- 将电化学数据与光谱特征相关联以获得机械洞察力.
主要方法:
- 使用时间解析面增强拉曼光谱 (TR-SERS).
- 使用循环电量计 (CV) 和脉冲电解 (PE) 进行电化学控制.
- 将电化学数据与TR-SERS光谱分析结合起来.
主要成果:
- 在低超电位 (-0.35 V_RHE) 时观察到CO2到CO的激活,法拉第效率为10%.
- 在PE中,随机CO中间体在正极偏差发生后立即占主导地位.
- 长时间的低超电位抑制了CO中间体;高偏差 (-0.55 V_RHE) 形成了静态CO中间体.
结论:
- 低过度的CO2到CO激活归因于Cu () 面暴露,部分氧化表面和铜碳酸中间体.
- 动态重组和表面中间体对CO2RR活动和选择性产生重大影响.
- 与电化学相结合的TR-SERS有效阐明了CO2RR机制.
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