Direct electrochemical CO 2 conversion using oxygen-mixed gas on a Cu network cathode and tailored anode.

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