Mechanistic Insights into OC-COH Coupling in CO2 Electroreduction on Fragmented Copper

Yao, Kaili; Li, Jun; Wang, Haibin; Lu, Ruihu; Yang, Xiaotao; Luo, Mingchuan; Wang, Ning; Wang, Ziyun; Liu, Changxu; Jing, Tan; Chen, Songhua; Cortes, Emiliano; Maier, Stefan A.; Zhang, Sheng; Li, Tieliang; Yu, Yifu; Liu, Yongchang; Kang, Xinchen und Liang, Hongyan (2022): Mechanistic Insights into OC-COH Coupling in CO2 Electroreduction on Fragmented Copper. In: Journal of the American Chemical Society, Vol. 144, No. 31: pp. 14005-14011

Abstract

The carbon-carbon (C-C) bond formation is essential for the electroconversion of CO2 into high-energy-density C2+ products, and the precise coupling pathways remain controversial. Although recent computational investigations have proposed that the OC-COH coupling pathway is more favorable in specific reaction conditions than the well-known CO dimerization pathway, the experimental evidence is still lacking, partly due to the separated catalyst design and mechanistic/spectroscopic exploration. Here, we employ density functional theory calculations to show that on low-coordinated copper sites, the *CO bindings are strengthened, and the adsorbed *CO coupling with their hydrogenation species, *COH, receives precedence over CO dimerization. Experimentally, we construct a fragmented Cu catalyst with abundant low-coordinated sites, exhibiting a 77.8% Faradaic efficiency for C2+ products at 300 mA cm-2. With a suite of in situ spectroscopic studies, we capture an *OCCOH intermediate on the fragmented Cu surfaces, providing direct evidence to support the OC-COH coupling pathway. The mechanistic insights of this research elucidate how to design materials in favor of OC-COH coupling toward efficient C2+ production from CO2 reduction.

• Item Type: Journal article
• Faculties: Physics
• Subjects: 500 Science > 530 Physics
• ISSN: 0002-7863
• Language: English