Advancements and challenges of industrial-level acidic CO2 electrolysis

Abstract

The use of green renewable energy to convert carbon dioxide (CO₂) into valuable chemicals and fuels through CO₂ electrolysis technology (also known as electrochemical CO₂ reduction reaction, eCO₂RR) is an advantageous technology, which could greatly aid the global carbon-neutral goal. Although progress has been made in alkaline/neutral media, low carbon conversion efficiency to target products, carbonate/bicarbonate salt precipitation, and blockage of electrode holes caused by CO₂ are not conducive to industrial applications. Acidic media could address these issues; however, in these conditions, there are other challenges that need to be addressed, such as hydrogen evolution, poor tolerance of electrocatalysts, and electrolysers. This review discusses recent advances in industrial-level acidic CO₂ electrolysis, including reaction mechanisms, electrocatalysts, and device design, aiming to promote its commercialization. In addition, a comprehensive evaluation strategy of an acidic eCO₂RR system is proposed, and perspectives are provided based on related discussion.