Fe-doped Co₃O₄ nanowire strutted 3D pinewood-derived carbon: A highly selective electrocatalyst for ammonia production via nitrate reduction

Nitrate (NO3-), a nitrogen-containing pollutant, is prevalent in aqueous solutions, contributing to a range of environmental and health-related issues. The electrocatalytic reduction of NO3- holds promise as a sustainable approach to both eliminating NO3- and generating valuable ammonia (NH3). Nevertheless, the reduction reaction of NO3- (NO3-RR), involving 8-electron transfer process, is intricate, necessitating highly efficient electrocatalysts to facilitate the conversion of NO3- to NH3. In this study, Fedoped Co3O4 nanowire strutted three-dimensional (3D) pinewood-derived carbon (Fe-Co3O4/PC) is proposed as a high-efficiency NO3-RR electrocatalyst for NH3 production. Operating within 0.1 M NaOH containing NO3-, Fe-Co3O4/PC demonstrates exceptional performance, obtain an impressively large NH3 yield of 0.55 mmol.h(-1).cm(-2) and an exceptionally high Faradaic efficiency of 96.5% at -0.5 V, superior to its Co3O4/PC counterpart (0.2 mmol.h(-1).cm(-2), 73.3%). Furthermore, the study delves into the reaction mechanism of Fe-Co3O4 for NO3-RR through theoretical calculations.