LAUSR

Significance The electrochemical reduction of nitrate to ammonia is a mild and efficient technique to reduce nitrate pollution in water and meet the demand for ammonia. Urgency for improvements in the efficiency of this process has accelerated the development of electrode materials. Herein, a phosphorus-modified cobalt single-atom catalyst (Co-SAC) was prepared with high atom economy based on the anchoring effect of a defect-rich carbon basal plane. The local environment of the Co atom was optimized by P-modification with asymmetric charge distribution and electron redistribution. The Co-SAC exhibited a high efficiency for ammonia production and good cycle stability due to its unique tetracoordinated structure, rendering it promising for the practical treatment of wastewater.