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 3 - 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 ads 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 3 - RR and water decomposition, especially the reactions between the intermediates of NO 3 - RR and water decomposition-provided H ads species. This catalytic NO 3 - RR exhibits an extremely high NH 3 yield of 80.92 mg h -1 cm -2 and a Faradaic efficiency (FE) of 95.2% in 1 M KOH containing 0.1 M NO 3 - . Significantly, 0.6W-O-CoP@NF presents greatly enhanced NH 3 yield and FE in a wide NO 3 - concentration ranges of 0.001-0.1 M compared to the reported. The excellent NO 3 - 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 ads , and meanwhile modulates the electronic structure of Co for strengthened adsorption of H ads and the H 2 release prevention, resultantly facilitating the NO 3 - RR. Finally, a Zn-NO 3 - 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.