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.