Promoting Nitrite-to-Ammonia Electroreduction over Amorphous CoS Nanorods.

Electrocatalytic nitrite reduction to ammonia (NORR) emerges as a promising route to simultaneously attain harmful NO removal and green NH synthesis. In this study, amorphous CoS nanorods (a-CoS) are first demonstrated as an effective NORR catalyst, which exhibits the maximum FE of 88.7% and NH yield rate of 438.1 μmol h cm at -0.6 V vs RHE. Detailed experimental and computational investigations reveal that the high NORR performance of a-CoS originates from the amorphization-induced S vacancies to facilitate NO activation and hydrogenation, boost the electron transport kinetics, and inhibit the competitive hydrogen evolution.