Advances in Carbon-Nitrogen Bond Formation From CO₂ and Nitrogenous Small Molecules Through Tandem Electrocatalysis

The electrocatalytic conversion of waste product molecules to valorized chemicals and fuels driven by clean energy is a promising approach to improving environmental health and alleviating the energy crisis. Historically, emphasis has been placed on CO₂ sequestration and electroreduction, as it makes up most greenhouse gas emissions, however, products obtained from CO₂ reduction are limited in variety. Coupling CO₂ reduction with nitrogenous small molecules (N₂, NO₃ ^-, NO₂ ^-, etc.) would expand the variety of valorized products while simultaneously increasing the removal of harmful environmental contaminants. In this review, the benefits of tandem catalysis promoting C─N bond coupling of CO₂ and nitrogenous small molecules are compared to traditional single site catalysis. Various tandem catalytic systems have been reported toward the electrosynthesis of urea, exhibiting high yield rates and extended catalytic stability. Innovative approaches have also facilitated the electrosynthesis of other organonitrogen compounds, including acetamide, methylamine, and formamide. Overall, advancements in tandem electrocatalysis signify considerable progress toward sustainable chemical synthesis, energy conservation, and emission reduction.