LaNi0.2Cu0.8O3‐δ Perovskites as Electrocatalysts for Electro‐synthesis of Ammonia from Nitrogen Oxyanion

Electrochemical nitrate reduction to ammonia (NO 3 RR) has become an attractive alternative way for sustainable ammonia synthesis. The development of electrocatalysts with high activity, stability and Faradaic efficiency is important but challenge due to the complex eight‐electron process. Herein, LaNi 0.2 Cu 0.8 O 2.77 (LNC) and LaNi 0.2 Cu 0.8 O 2.53 (LNC−Ar) are demonstrated as electrocatalysts towards NO 3 RR and the surface reconstruction of the two catalysts was found to have strong effect on the catalytic performance. LNC−Ar shows a superior performance than LNC, with a maximum NH 4 + yield of 11.49±1.20 mg h −1 cm −2 and a Faradaic efficiency of 87.10±1.34 % in 0.5 M NO 3 − , besides, the LNC−Ar remains functionally stable along the long‐time electrolysis. DFT results reveals the reconstructed LaNi 0.2 Cu 0.8 O 2 (LNCO 2 ) has the best ability to adsorb *NO 3 , resulting in a better performance towards NO 3 RR. Further, the better performance on LNC−Ar with more LNCO 2 can be well explained. This work opens a new sight on perovskites towards NO 3 RR and provides an option of active and stable electrocatalyst for sustainable ammonia synthesis.