Pulsed-potential electrolysis enhances nitrate reduction and C–N coupling upgrading

Abstract Converting harmful nitrate waste into value-added chemicals represents a promising alternative for achieving the electrocatalytic upgrading of NO ₃ ⁻ and maintaining the global nitrogen balance. Nonetheless, improving the electrochemical performance and revealing reaction mechanisms still requires further investigation to meet the practical application requirements. Herein, we summarize the development of electrochemical NO ₃ ⁻ reduction reaction (NO ₃ RR) and C–N coupling reaction under pulsed-potential conditions. In the section on NO ₃ RR, the electrocatalytic reaction systems for direct conversion of NO ₃ ⁻ to NH ₃ are summarized. In the section on coupling, the C–N coupling reactions of NO ₃ ⁻ with CO ₂ for urea synthesis, and with organic molecules for amino compounds synthesis are reviewed. The corresponding reaction mechanisms for different reaction systems are compared with the aid of theoretical calculations. Finally, the challenges and future perspectives are proposed. The pulsed-potential electrolysis for nitrate reduction not only increases the concentration of the local NO ₃ ⁻ , key reactant, and intermediate species, but also restores the oxidation state of the active sites, providing guidance and reference for a nitrogen economy.