Boosting electrochemical nitrate-to-ammonia conversion by self-supported MnCoO nanowire array.

Direct electrocatalytic reduction of nitrate (NO) is an efficient route to simultaneously synthesize ammonia (NH) and remove NO pollutants under ambient conditions, however, it is hindered by the lack of efficient and stable catalysts. Herein, a self-supported spinel-type MnCoO nanowire array is demonstrated for exclusively catalyzing the conversion of NO to NH, achieving a high Faradic efficiency of 97.1% and a large NH yield of 0.67 mmol h cm. Furthermore, density functional analysis reveals that MnCoO (220) surface has high activity for NO reduction with a low energy barrier of 0.46 eV for *NO to *NOH.