Valorizing carbon dioxide via electrochemical reduction on gas‐diffusion electrodes

The electrochemical carbon dioxide (CO 2 ) reduction provides a means to upgrade CO 2 into value‐added chemicals. When powered by renewable electricity, CO 2 electroreduction holds the promise of chemical manufacturing with carbon neutrality. A commercially relevant CO 2 electroreduction process should be highly selective and productive toward desired products, energetically efficient for power conversion, and stable for long‐term operation. To achieve these goals, designing gas‐diffusion catalytic electrodes and prototyping reactors built upon in‐depth understandings of the reaction mechanisms are of paramount importance. In this review, the fundamentals of gas‐diffusion electrodes are briefly presented. Then, the most recent advances in developing high‐performance CO 2 reduction using gas‐diffusion electrodes are overviewed. Reactor engineering aiming at enhancing productivity, energy efficiency, CO 2 single‐pass utilization, and operating lifetime is further discussed. Challenges in developing CO 2 electroreduction systems are included. The prospects for advancing CO 2 electroreduction toward practical applications are also narrated.