In-situ spectroscopic probe of the intrinsic structure feature of single-atom center in electrochemical CO/CO2 reduction to methanol
Xinyi Ren, Jian Zhao, Xuning Li, Junming Shao, Binbin Pan, Aude Salamé, Etienne Boutin, Thomas Groizard, Shifu Wang, Jie Ding, Xiong Zhang, Wen‐Yang Huang, Wen‐Jing Zeng, Chengyu Liu, Yanguang Li, Sung‐Fu Hung, Yanqiang Huang, Marc Robert, Bin Liu
Abstract
Abstract While exploring the process of CO/CO 2 electroreduction (CO x RR) is of great significance to achieve carbon recycling, deciphering reaction mechanisms so as to further design catalytic systems able to overcome sluggish kinetics remains challenging. In this work, a model single-Co-atom catalyst with well-defined coordination structure is developed and employed as a platform to unravel the underlying reaction mechanism of CO x RR. The as-prepared single-Co-atom catalyst exhibits a maximum methanol Faradaic efficiency as high as 65% at 30 mA/cm 2 in a membrane electrode assembly electrolyzer, while on the contrary, the reduction pathway of CO 2 to methanol is strongly decreased in CO 2 RR. In-situ X-ray absorption and Fourier-transform infrared spectroscopies point to a different adsorption configuration of *CO intermediate in CORR as compared to that in CO 2 RR, with a weaker stretching vibration of the C–O bond in the former case. Theoretical calculations further evidence the low energy barrier for the formation of a H-CoPc-CO – species, which is a critical factor in promoting the electrochemical reduction of CO to methanol.