通过Cu-Si结合接口将电还原选择性转换为乙烯
Wan-Feng Xiong1,2, Duan-Hui Si1, Hong-Fang Li1,3
1State Key Laboratory Structural Chemistry, Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences, Fuzhou 350002, China.
Journal of the American Chemical Society
|December 22, 2023
概括
设计一种新型的铜催化剂 (p-Cu@m-SiO2) 提高了电化学二氧化碳降解 (CO2RR) 到乙烯的速度. 这种核心外结构提高了选择性和电流密度,为高效的二氧化碳转化提供了有前途的策略.
科学领域:
- 电化学
- 材料科学
- 催化剂
背景情况:
- 铜 (Cu) 是电化学二氧化碳减排 (CO2RR) 的独特催化剂,因为它能够产生多碳产品.
- 设计高效的基于的催化剂和理解它们的结构-活动关系对于CO2RR仍然是一个重大挑战.
研究的目的:
- 合理设计一个核心外结构的铜催化剂 (p-Cu@m-SiO2),具有直接的Cu-Si结合,以实现高效和选择性的CO2RR.
- 阐明在设计的催化剂上控制CO2RR选择性的反应机制和结构-活性关系.
主要方法:
- 通过直接的Cu-Si结合合成核心外结构的铜催化剂 (p-Cu@m-SiO2).
- 包括电流密度测量在内的电化学表征.
- 使用动态同位素效应,局部减弱的全反射里埃变换红外光谱 (ATR-FTIR) 和密度函数理论 (DFT) 计算的机制研究.
主要成果:
- p-Cu@m-SiO2催化剂显著提高了对C2H4的CO2RR选择性,C2H4/CH4产物比率从0.6增加到14.4.
- 达到高电流密度,最高可达450 mA cm-2.
- 确定SiO2外稳定*H中间体,而Cu-Si接口促进*CHO和*CO中间体的合形成C2H4.
结论:
- 在p-Cu@m-SiO2核心外结构中的直接Cu-Si结合对于CO2RR中的高C2H4选择性至关重要.
- 催化剂的设计有效地抑制了演变反应,并促进了C-C合.
- 这项工作提出了开发先进的基于的催化剂的可行策略,用于选择性地将二氧化碳转化为有价值的多碳产品.
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