In Situ Raman Spectroscopic Studies of Electrochemical CO<sub>2</sub> Reduction on Cu-Based Electrodes
Zi‐Yu Du, Kun Wang, Si-Bo Li, Yimeng Xie, Jing‐Hua Tian, Qing‐Na Zheng, Weng Fai Ip, Hua Zhang, Jian‐Feng Li, Zhong‐Qun Tian
Abstract
The electrochemical CO 2 reduction reaction (CO 2 RR), which utilizes renewable energy to produce carbon-neutral chemicals and fuels, offers a potential pathway toward achieving global carbon neutrality. Cu-based catalysts have gained significant attention in this field due to their unique coupling ability to convert CO 2 into multicarbon products, while maintaining high Faradaic efficiency. However, the CO 2 RR process is complex, involving a multistep proton–electron transfer process that involves intermediates associated with carbon- and oxygen-containing species. Therefore, this work aims to review the recent progress of in situ surface-enhanced Raman spectroscopic (SERS) studies of CO 2 RR on Cu-based catalysts. The possible reaction mechanism of CO 2 RR has been first discussed. In situ SERS studies of CO 2 RR on Cu-based single-crystal electrodes and nanocatalysts with different electronic states, morphologies, and compositions have been reviewed, and various intermediates during CO 2 RR have been captured to clarify the reaction mechanisms and structure–activity relationships. Moreover, the future opportunities and challenges for CO 2 RR electrocatalysis are presented. This review will provide fundamental insights for the understanding of CO 2 RR mechanisms and the design of more efficient, selective, and stable CO 2 RR catalysts.