Linking catalytic selectivity and water management in Cu based gas diffusion electrodes for high-rate CO electrolysis

Cu-based electrolyzers allow high-rate CO2 electrolysis (CO2E) to value-added chemicals. However, they still suffer from a lack of stability and high selectivity towards the hydrogen evolution reaction (HER) instead of CO2E. Both issues are believed to be due to insufficient water management. Our theory is that too high a water content in the catalyst and gas diffusion layer is limiting CO2 mass transfer, leaving HER as the only feasible reaction. While our previous work (MA-4791) showed water transport with CO2 electrolysis, the dominant anions are carbonates, and thus the main ion transport through the membrane is carbonate ions. With this proposal, we wish to employ CO electrolysis, as that has similar catalysis as CO2E, but is expected to have vastly different water flux due to hydroxyl groups being the dominant anions. In this proposal, we aim to analyze water flux with COE and relate this to variations in catalytic selectivity as well as relate it to our previous work of CO2E.