Selective ammonia production via nitrite electroreduction over CoFe layered double hydroxides-decorated 3D TiO 2 array

Water-soluble nitrite (NO2−) in wastewater from agricultural and industrial activities poses ecological and health risks, and its electroreduction shows promise for ammonia (NH3) production, but energy losses from the hydrogen evolution reaction (HER) limit its overall efficiency. In this work, we report the use of CoFe-layered double hydroxides on 3D TiO2 array (TiO2@CoFe-LDH/TP) as an effective electrocatalyst for NO2− reduction. By offering superior *H species supply and hydroprocessing capability, this catalyst achieves an NH3 yield of 1056.4 μmol h−1 cm−2 with a 97.4% Faradaic efficiency (FE) at −0.6 V and sustains FE above 87% across a range of applied potentials. Additionally, a 60-h simulated…