Copper Electrocatalyst Produced by Cu2(OH)2CO3-Mediated In Situ Deposition for Diluted CO2 Reduction to Multicarbon Products

Pure CO2 is commonly used in most of the current studies for electrochemical CO2 reduction which will need a further cost of gas purification and separation. However, the limited works on diluted CO2 reduction are focused on CO or CH4 production other than C-2 products. In this work, copper electrocatalysts were prepared by Cu-2(OH)(2)CO3-mediated in situ deposition for diluted CO2 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 CO2 reduction. The optimized Cu catalyst achieves a C-2 Faradaic efficiency as high as 60.72% in the presence of merely 25% CO2, which is almost equivalent to that observed with pure CO2.