Copper Electrocatalyst Produced by Cu 2 (OH) 2 CO 3 -Mediated In Situ Deposition for Diluted CO 2 Reduction to Multicarbon Products.

Pure CO 2 is commonly used in most of the current studies for electrochemical CO 2 reduction which will need a further cost of gas purification and separation. However, the limited works on diluted CO 2 reduction are focused on CO or CH 4 production other than C 2 products. In this work, copper electrocatalysts were prepared by Cu 2 (OH) 2 CO 3 -mediated in situ deposition for diluted CO 2 reduction to multicarbon products. Using in situ Raman spectroscopy, constant amounts of CO and OH* were observed on the catalyst surface, which could effectively suppress the high kinetics of hydrogen evolution and promote C-C coupling, especially under the condition of diluted CO 2 reduction. The optimized Cu catalyst achieves a C 2 Faradaic efficiency as high as 60.72% in the presence of merely 25% CO 2 , which is almost equivalent to that observed with pure CO 2 .