Atomically dispersed Fe atoms anchored on S and N–codoped carbon for efficient electrochemical denitrification

Significance Denitrification by electrochemistry is a mild and efficient technique to reduce nitrate pollution in water. The urgency of finding a wastewater treatment has accelerated electrode material development. Here, (S) N-modified, carbon-supported Fe or Cu single-atom catalysts (SACs) were prepared using the anchoring effect of a defect-rich carbon basal plane with high activity and atom economy. Fe-CNS exhibits the highest Fe utilization in electrodenitrification among all reported studies. The coordination environment of Fe atoms was optimized by S-doping with asymmetric charge distribution and electron redistribution, resulting in higher activity of nitrate reduction. The atomic-level structure–activity relationship and reaction mechanism were investigated. The unique structure of Fe SACs renders them promising for the practical removal of pollutants in water.