Dual-site W-O-Cop Catalysts for Active And Selective Nitrate Conversion to Ammonia in A Broad Concentration Window.

Environmentally friendly electrochemical reduction of contaminated nitrate to ammonia (NO RR) is a promising solution for large quantity ammonia production, which, however, is a complex multi-reaction process involving coordination between different reaction intermediates of nitrate reduction and water decomposition-provided H species. Here, a dual-site catalyst of [W-O] group-doped CoP nanosheets (0.6W-O-CoP@NF) has been designed to synergistically catalyze the NO RR and water decomposition, especially the reactions between the intermediates of NO RR and water decomposition-provided H species. This catalytic NO RR exhibits an extremely high NH yield of 80.92 mg h cm and a Faradaic efficiency (FE) of 95.2% in 1 M KOH containing 0.1 M NO . Significantly, 0.6W-O-CoP@NF presents greatly enhanced NH yield and FE in a wide NO concentration ranges of 0.001-0.1 M compared to the reported. The excellent NO RR performance is attributed to a synergistic catalytic effect between [W-O] and CoP active sites, in which the doped [W-O] group promotes the water decomposition to supply abundant H , and meanwhile modulates the electronic structure of Co for strengthened adsorption of H and the H release prevention, resultantly facilitating the NO RR. Finally, a Zn-NO battery has been assembled to simultaneously achieve three functions: electricity output, ammonia production and nitrate treatment in wastewater. This article is protected by copyright. All rights reserved.