Electrochemical CO₂ reduction in acidic media: a perspective

Abstract

The electrochemical CO₂ reduction reaction (eCO₂RR) is a promising approach for converting CO₂ to useful chemicals and, hence, achieving carbon neutrality. Though high selectivity and activity of products have been achieved recently, all are reported in neutral or alkaline electrolytes. Although these electrolyte media give high selectivity and activity, they face the major challenge of low CO₂ utilization because of carbonate formation, which lowers the overall efficiency of the process. Conducting the eCO₂RR in acidic media can help overcome the issue of carbonate formation and hence can increase the CO₂ utilization efficiency. However, there are many challenges associated with acidic eCO₂RR. Two major concerns are the highly competitive hydrogen evolution reaction in acidic media and salt precipitation issues. This Perspective focuses on the fundamentals of acidic eCO₂RR, recent catalyst development strategies, and relevant problems that need to be addressed in the future. In the end, we provide a future outlook that will give an idea about the problems to focus on in the future in the field of acidic eCO₂RR.