Toward effective electrocatalytic C-N coupling for the synthesis of organic nitrogenous compounds using CO₂ and biomass as carbon sources

Thermochemical conversion of fossil resources into fuels, chemicals, and materials has rapidly increased atmospheric CO2 levels, hindering global efforts toward achieving carbon neutrality. With the increasing push for sustainability, utilizing electrochemical technology to transform CO2 or biomass into value-added chemicals and to close the carbon cycle with sustainable energy sources represents a promising strategy. Expanding the scope of electrosynthesis technology is a prerequisite for the electrification of chemical manufacturing. To this end, constructing the CN bond is considered a priority. However, a systematic review of electrocatalytic processes toward building CN bonds using CO2 and biomass as carbon sources is not available. Accordingly, this review highlights the research progress in the electrosynthesis of organic nitrogen compounds from CO2 and biomass by CN coupling reactions in view of catalytic materials, focusing on the enlightenment of traditional catalysis on CN coupling and the understanding of the basis of electrochemical CN coupling. The possibility of CN bond in electrocatalysis is also examined from the standpoints of activation of substrates, coupling site, mechanism, and inhibition of hydrogen evolution reaction (HER). Finally, the challenges and prospects of electrocatalytic CN coupling reactions with improved efficiency and selectivity for future development are discussed.