增强的中间体在Ag单原子合金上的迁移,以提高CO2的多碳产品选择性
Min Wang1,2, Minghui Fang1,2, Yingxuan Liu1,2
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
|May 2, 2025
概括
这项研究引入了一种新的银铜单原子合金级联催化剂 (AgCu-SAA),用于电化学二氧化碳还原反应 (CO2RR). 通过提高一氧化碳中间体的利用,催化剂显著提高了多碳产品的选择性.
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) 对碳循环管理和能源解决方案至关重要.
- 在CO2RR中,实现多碳 (C2+) 产品的高选择性仍然是一个重大挑战.
- 有效利用一氧化碳等中间体是提高CO2RR性能的关键.
研究的目的:
- 开发一种新的催化剂,以提高电化学二氧化碳降低到C2+产品的选择性.
- 在级催化系统中研究二氧化碳中间利用的机制.
- 在工业相关的电流密度下实现高法拉达效率的C2+产品.
主要方法:
- 通过环氧凝方法制造银铜单原子合金级联催化剂 (AgCu-SAA).
- 电化学表征包括循环电压测量和时电压测量.
- 在现场进行拉曼光谱和密度函数理论 (DFT) 计算以阐明反应机制.
主要成果:
- AgCu-SAA催化剂在900 mA cm-2下实现了C2+产品的法拉第效率 (FE) 为83.4%.
- 即使在高电流密度为1100 mA cm-2的情况下,C2+产品的高FE (74. 8%) 也保持不变.
- 在现场和DFT研究证实了从Ag单原子位点到相邻Cu位点的直接CO转移,从而提高了CO利用率.
结论:
- AgCu-SAA催化剂通过促进二氧化碳中间体之间的迁移途径,有效地促进了CO2RR到C2+产品的转化.
- 这种级联催化方法显著提高了选择性和效率,克服了二氧化碳脱吸的局限性.
- 这些发现为设计高效电化学二氧化碳转换的先进催化剂提供了有希望的策略.
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