Syngas Synthesis at 1.7V and 200mA/cm2 via BPM Electrolysis of CO2 Capture and Aldehyde Solution

We demonstrate an electrochemical syngas production platform that couples bicarbonate electrolysis with formaldehyde oxidation in a bipolar membrane electrode assembly. This strategy doubles syngas (CO + H2) throughput compared to conventional CO2 electrolysis by generating CO at the cathode and H2 at the anode. The system achieves a full-cell voltage of 1.7 V while operating at an industrially relevant current density of 200 mA cm-2. The system maintained a combined Faradaic efficiency of 200% over 8 hours. The process produces gas with a 1:1 H2:CO ratio, aligning with downstream requirements for Fischer-Tropsch synthesis. We further investigated how Cu anode active sites and electrolyte composition affect formaldehyde oxidation activity. Our integrated electrolytic system reduces levelized energy by 46% to 61% relative to conventional electrochemical syngas production platforms.