A disquisition on CO2 electroreduction to C2H4: An engineering and design perspective looking beyond novel choosy catalyst materials

Production of ethylene (C2H4) from Carbon dioxide (CO2) is a promising and effective approach for mitigating the adverse greenhouse effect of anthropogenic CO2 emission from human activities including chemical industries along with energy deficiency caused by the burning of nonrenewable fossil fuels. The C2H4, one of the utmost extensively employed chemical compounds, is readily converted into various valuable products that can substitute those derived from fossil fuels. Electrochemical reduction is a process of converting CO2 into C2H4 in which the electrocatalysts, electrolyzer and electrolyte all play the critical role. Despite considerable improvements in electrochemical CO2 reduction but its efficacy is still hindered by a number of complications, including the deprived mass transfer efficiency of the electrolyzer, the high cost, low activity, poor stability and limited selectivity of electrocatalysts towards C2H4. Accomplishments to date in CO2 electroreduction to C2H4 have been inspiring, while extensive advances are still required for it to develop a profitable technology able to move society towards renewable energy sources. The current review demonstrates a unified discussion on recent progress in the area of CO2 reduction to C2H4. The role of a class of promising advanced electrocatalysts, electrolytes and the design of electrolyzer in the electrochemical reduction method is thoroughly reviewed. We also highlight the current developments in photocatalytic CO2 reduction to C2H4. Lastly, this review is concluded by deliberating the current challenges that are encountered during the production of C2H4 from CO2 electrochemical reduction with an objective of revolutionary futuristic developments. This article will provide comprehensive knowledge to the readers on CO2 electrochemical reduction to C2H4 production.