Fe-Doped CoS₂ Nanoarrays: Efficient Electrocatalytic Nitrate Reduction to Ammonia under Ambient Conditions

The electrocatalytic nitrate reduction reaction (NO₃ ^- RR) enables the reduction of nitrate to ammonium ions under ambient conditions. It was considered as an alternative reaction for the production of ammonia (NH₃ ) in recent years. In this paper, we report that the Fe doping CoS₂ nanoarrays can effectively catalyze the formation of NH₃ from nitrate (NO₃ ^- ) under ambient conditions. This is mainly due to the increase of the NO₃ ^- reaction active site by Fe doping and the porous nanostructure of the catalyst, which greatly improves the catalytic activity. Specifically, at -0.9 V vs. RHE, the NH₃ yield rate (R_NH3 ) of Fe-CoS₂ /CC is 17.8×10^-2  mmol h^-1  cm^-2 with Faraday Efficiency (FE) of 88.93 %. Besides, such catalyst shows good durability and catalytic stability, which provides the possibility for the future application of electrocatalytic NH₃ production.