Theoretical insights into the factors affecting the electrochemical reduction of CO₂

The harmonious condition between nature and humans experiences severe challenges due to the continuous consumption of fossil fuels and the consequent rapid release of large CO2 levels into the atmosphere. It is urgent to explore sustainable resources of green energy and develop efficient techniques for CO2 conversion into value-added products. Being an indispensable component for CO2 re-utilization, the conversion of CO2 into valuable chemicals and fuels can provide a win-win situation to accomplish the effective exploitation of carbon resources and reduce the large volumes of CO2. Among the presently adopted CO2 conversion techniques, the electrochemical approach is a promising route to produce low carbon chemicals required for heavy-duty applications. Although significant progress has been accomplished in the electrochemical reduction of CO2 (ERC), there is a lack of basic research to understand the different factors that strongly influence the performance of ERC. In particular, very few studies have incorporated the effect of an electrolytic cell on ERC. This review summarizes the role of metal electrodes in the production of different products, the effect of the electrolyte, pressure and temperature, membrane, and CO2 mass transfer coefficient on the performance of ERC. Moreover, we have also comprehensively discussed the different types of an electrolytic cell in terms of their structure, working principle and capabilities of producing selective products to understand the impact of different cell configurations on the reduction process, and have presented a useful review of the future research prospects.