Nitrate Electroreduction to Ammonia over Copper‐based Catalysts

The electrocatalytic reduction of nitrate (NO3−) to ammonia (NH3) holds substantial promise, as it transforms NO3− from polluted water into valuable NH3. However, the reaction is limited by sluggish kinetics and low NH3 selectivity. Cu‐based catalysts with unique electronic structures demonstrate rapid NO3− to NO2− rate‐determining step (RDS) and fast electrocatalytic nitrate reduction reaction (eNO3RR) kinetics among non‐noble metal catalysts. Nonetheless, achieving high robustness and selectivity for NH3 with Cu‐based catalysts remains a significant challenge. This review provides a comprehensive overview of the reaction mechanisms in eNO3RR, highlights how the structures of monometallic and bimetallic Cu‐based catalyst affect catalytic properties, and discusses the current challenges as well as prospects in eNO3RR.