邻近的铜单原子促进电化学CO2的C-C合,以减少乙醇的有效转化
Wei Xia1, Yijun Xie1, Shuaiqiang Jia1
1Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China.
Journal of the American Chemical Society
|July 27, 2023
概括
研究人员开发了一种用于电化学二氧化碳减排反应 (CO2RR) 产生乙醇的新催化剂. 这种先进的铜单原子催化剂实现了高效率和选择性, 对于碳中和目标至关重要.
科学领域:
- 电化学
- 催化剂
- 材料科学
背景情况:
- 电化学二氧化碳减排反应 (CO2RR) 对于碳中和至关重要.
- 基于铜的催化剂对CO2RR有效,但缺乏乙醇选择性和电流密度.
- 乙醇是一种有价值的化学物质和燃料,
研究的目的:
- 开发一种有效的催化剂,用于选择性电化学二氧化碳降解为乙醇.
- 在CO2RR中研究催化剂结构和性能之间的关系.
- 为了实现乙醇生产的高法拉第效率和电流密度.
主要方法:
- 用介导的有机框架 (HOF) 模板合成Cu单原子催化剂 (SAC).
- 在薄壁N-doped碳纳米管 (TWN) 上制备超高密度Cu SAC.
- 在H型电池中进行电化学CO2RR测试,包括法拉第效率和电流密度测量.
- 密度功能理论 (DFT) 计算以阐明活性位点和反应机制.
主要成果:
- 在TWN催化剂上达到超高的Cu负载 (高达13.35%).
- 证明了CO2RR对乙醇的卓越性能,乙醇的法拉第效率随着Cu-N3位点密度的增加而增加.
- 在 35.6 mA cm-2 的部分电流密度下达到了创纪录的~ 81.9% 的法拉达效率.
- 催化剂表现出超过25小时的运行稳定性.
- 确定了邻近的Cu-N3位点作为促进C-C合的关键活跃中心.
结论:
- 开发的Cu SAC在电化学CO2RR方面表现优于乙醇.
- 邻近Cu-N3活性位点的高密度对于提高乙醇选择性和生产至关重要.
- 这种方法为有效的二氧化碳转化为有价值的产品提供了有希望的策略,有助于实现碳中和.
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