CO2 Electroreduction at Low Overpotential on Oxide-Derived Cu/Carbons Fabricated from Metal Organic Framework

Electrochemical reduction of CO2 to chemical feedstocks is an attractive solution that prevents CO2 accumulation in the atmosphere, but it remains a great challenge to develop the cost-effective catalysts. Herein, we synthesized oxide-derived Cu/carbon (OD Cu/C) catalysts by a facile carbonization of Cu-based MOF (HKUST-1). The resulting materials exhibited highly selective CO2 reduction to alcohol compounds with total faradic efficiencies of 45.2-71.2% at -0.1 to -0.7 V versus reversible hydrogen electrode (RHE). High-yield methanol and ethanol has been achieved on OD Cu/C-1000 with the production rates of 5.1-12.4 and 3.7-13.4 mg L-1 h(-1), respectively. Notably, the onset potential for C2H5OH formation is near -0.1 V (versus RHE), corresponding to similar to 190 mV of overpotential, which is among the lowest overpotentials reported to date for the reduction of CO2 to C2H5OH. The improvements in activity and selectivity of the oxide-derived Cu/carbon might be attributed to the synergistic effect between the highly dispersed copper and the matrix of porous carbon. These findings provide a new insight into design of practical catalysts for decreasing atmospheric CO2 levels and synthesizing liquid fuels.