Identification of CO<sub>2</sub> as a Reactive Reagent for C–C Bond Formation via Copper-Catalyzed Electrochemical Reduction
Wen‐Yu Lin, Zong‐Xian Chen, Haocheng Xiong, Hsien-Chin Li, Yeu‐Shiuan Ho, Chi-Tien Hsieh, Qi Lu, Mu‐Jeng Cheng
Abstract
The electrochemical reduction of CO 2 (CO 2 ER) holds great promise as a method to achieve carbon neutrality and revolutionize the utilization of fossil fuels. Advanced catalysts used in CO 2 ER have demonstrated the ability to generate valuable multi-carbon products through the formation of carbon–carbon (C–C) bonds. Previous research has predominantly focused on C–C formation by dimerizing *CO or coupling *CO with other *C 1 intermediates. However, the potential coupling of CO 2 with *C 1 intermediates has not been explored experimentally or theoretically despite CO 2 being the exclusive reactant in CO 2 ER and having a high concentration. This study employed DFT calculations and a constant electrode potential model to investigate the possibility of CO 2 + *C 1 couplings on Cu(100) surfaces. Surprisingly, the results indicate that CO 2 can serve as a favorable reagent for C–C bond formation, surpassing the reactivity of *CO under alkaline conditions. The enhanced reactivity of CO 2 compared to that of *CO was elucidated based on a barrier decomposition analysis. Experimental validation was conducted to confirm these theoretical results.