Promoting Nitrite-to-Ammonia Electroreduction over Amorphous CoS₂ Nanorods

Abstract

Electrocatalytic nitrite reduction to ammonia (NO 2 RR) emerges as a promising route to simultaneously attain harmful NO 2 − removal and green NH 3 synthesis. In this study, amorphous CoS 2 nanorods (a-CoS 2 ) are first demonstrated as an effective NO 2 RR catalyst, which exhibits the maximum FE NH3 of 88.7% and NH 3 yield rate of 438.1 μmol h −1 cm −2 at −0.6 V vs RHE. Detailed experimental and computational investigations reveal that the high NO 2 RR performance of a-CoS 2 originates from the amorphization-induced S vacancies to facilitate NO 2 − activation and hydrogenation, boost the electron transport kinetics, and inhibit the competitive hydrogen evolution.