保持分子调,以提高电催化CO2转化为乙醇的电催化转化
Weiwei Fu1, Yuke Li2, Jiayi Chen1
1Department of Chemical and Biomolecular Engineering, National University of, Singapore, 4 Engineering Drive 4, 117585, Singapore.
Angewandte Chemie (International ed. in English)
|August 14, 2024
概括
在铜催化剂上用保护层保护分子添加剂,可显著增强CO2电还原 (CO2R) 到乙醇等多碳产品,即使在高电流密度下也能实现高选择性.
科学领域:
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 用分子添加剂修改催化剂表面可以提高电催化性能.
- 保存这些添加剂并最大限度地发挥它们的作用,尤其是在高电流密度下,仍然是一个挑战.
研究的目的:
- 开发一种在电极表面保存分子添加剂的策略.
- 通过使用受保护的分子添加剂,增强CO2电还原 (CO2R) 到多碳产品.
主要方法:
- 功能化一个铜催化剂与4-dimethylaminopyridine (DMAP) 作为一个分子添加剂.
- 应用一种疏水性保护层,以防止在二氧化碳电还原过程中DMAP出.
- 利用动力分析,现场光谱学和理论计算来理解这种机制.
主要成果:
- 保护层有效地防止了DMAP的漏,将其限制在催化剂表面.
- 用DMAP功能化的Cu在0.47V和RHE时对多碳产品具有80%以上的选择性,而原始Cu的选择性为35%左右.
- 在400 mA cm-2的高电流密度下,乙醇选择性达到近50%,DMAP促进了C-C合和乙醇形成.
结论:
- 一个保护层策略有效地保留了分子添加剂,以提高CO2R.
- 在Cu催化剂上的DMAP限制通过电子积累促进了多碳的形成,并促进了C-C合.
- 这种方法为设计先进的分子调节电催化剂提供了一条途径.
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