Advanced insights towards electrochemical urea synthesis: Strategic design and techno–commercial compatibility

Abstract

The industrial production of urea involves two sequential steps, reaction of nitrogen and hydrogen to form ammonia followed by the reaction of the ammonia with carbon dioxide, so the process is capital expensive, massive energy consuming and complex synthesis process with multiple cycles to increase the production efficiency. The electrocatalytic C–N coupling reaction to specifically produce urea by simultaneous activation followed by co-reduction of carbon dioxide (CO2) and nitrogen sources (N2, NO2– or NO3–) at ambient condition presents a sustainable and eco-friendlier alternate route for urea production by a single step process. However, there are several challenges like adsorption capabilities of the reactants on the substrates followed by activation, suppression of hydrogen evolution reaction and finally effective C–N bond formation to specifically produce urea. In this work we showcase the road map of the electrocatalytic green urea production, with concise yet precise discussion on potential electrocatalyst, electrochemical working cell, mechanistic insight of urea synthesis, techno–commercial aspects and finally conclude with the future prospect of the green urea production.