Challenges and Opportunities in Electrocatalytic CO Reduction to Chemicals and Fuels.

The global temperature increase must be limited to below 1.5 °C to alleviate the worst effects of climate change. Electrocatalytic CO reduction (ECO R) to generate chemicals and feedstocks is considered one of the most promising technologies to cut CO emission at an industrial level. However, despite decades of studies, advances at the laboratory scale have not yet led to high industrial deployment rates. This Review discusses practical challenges in the industrial chain that hamper the scaling-up deployment of the ECO R technology. Faradaic efficiencies (FEs) of about 100 % and current densities above 200 mA cm have been achieved for the ECO R to CO/HCOOH, and the stability of the electrolysis system has been prolonged to 2000 h. For ECO R to C H , the maximum FE is over 80 %, and the highest current density has reached the A cm level. Thus, it is believed that ECO R may have reached the stage for scale-up. We aim to provide insights that can accelerate the development of the ECO R technology.