Carbonized Yolk-shell Metal-Organic Frameworks for Electrochemical Conversion of CO_(2) into Ethylene

With the excessive consumption of fossil fuels and the massive emission of CO_(2),it has led to a series of environmental crises posing a serious threat to sustainable development.Electrochemical CO_(2) reduction reaction( CO_(2)RR)to ethylene helps solve these serious environmental crises.Herein,we report the synthesis of a copper-based electrocatalyst by pyrolysis of yolk-shell structured HKUST-1 with partial substitution of trimesic acid by benzimidazole(nitrogen source).The electrocatalyst exhibits an ethylene Faradic efficiency(FE)of 25.8%and a partial ethylene current density of 23.7 mA/cm^(2),in addition,the electrocatalyst can maintain stable performance during 10 h of electrolysis,which are all better than those of the electrocatalyst without nitrogen dopant.According to electrochemical measurements and X-ray photoelectron spectroscopy(XPS),we propose that the nitrogen dopant plays an effective role in stabilizing Cu(I)species and promoting CO_(2) molecules activation,as well as suppressing the reduction of Cu(I)species during electrolysis.Eventually,the performance of the electrocatalyst toward CO_(2)RR is studied in a flow cell.This work provides a new route for the design of Cu-based electrocatalyst toward electrochemical CO_(2) conversion into ethylene.