Direct electrochemical CO2 conversion using oxygen-mixed gas on a Cu network cathode and tailored anode.

Abstract

Electrochemical CO2 reduction (eCO2R) by direct introduction of 60% air-containing CO2 mixed gas was demonstrated using a porous Cu network cathode formed on a hydrophobic gas diffusion layer (Cu/P-GDL). Cu/P-GDL exhibited eCO2R using the mixed gas with a remarkable faradaic efficiency of 85% for the production of C2+ chemicals, whereas a Cu cathode constructed on a conventional carbon gas diffusion layer (Cu/C-GDL) produced neither eCO2R products nor H2. Furthermore, the electrolyzer with Cu/P-GDL and optimized anode configuration achieved a partial current density of 132 mA cm-2 for C2+ chemicals even in the presence of 12% O2. Demonstration of eCO2R with impure CO2 gas would greatly expand its future applications.