A Nature-Inspired Solution for Water Management in a Zero-Gap CO2 Electrolyzer.

Electroreduction of carbon dioxide (CO2RR) holds great promise as a CO2 emission mitigation strategy while producing valuable chemicals. This study draws inspiration from desert-dwelling lizards to design a flow-field that increases the performance of the CO2RR in a zero-gap CO2 electrolyzer. It achieves a CO partial current density of 165.5 mA cm-2 at 200 mA cm-2, surpassing those of conventional parallel and serpentine flow-field designs. Unlike more complex strategies that can only partially prevent water flooding or salt precipitation, our approach achieves both, solely by modifying the cathodic flow-field, while using commercial electrocatalysts, membranes, and standard operating conditions. When doubling the cell size, the lizard-inspired serpentine flow-field significantly boosts CO production: CO selectivity is 46% and 97% higher than for a conventional serpentine flow-field at 350 mA cm-2 and 400 mA cm-2, respectively. Thus, lizard-inspired flow-field technology could provide a step-change in stable, scalable CO2RR, even using commercially available components for the use of CO2 electrolyzers.