Electrochemical Nitrate Reduction to Ammonia using γ-Fe<sub>2</sub>O<sub>3</sub>/BCN in a Neutral Medium
Soniya Mariya Varghese, Anju Vakakuzhiyil Gopinathan, Sudhin Rathnakumaran, Suraj Sasikumar, Sooraj Kunnikuruvan, G. Ranga Rao
Abstract
Electrochemical reduction of nitrate, which is a widespread pollutant, offers an alternate approach for the ammonia synthesis. Developing a stable catalyst that can selectively reduce nitrate to ammonia in a neutral medium is considered in this study. An active catalyst based on iron oxide supported on boron carbon nitride (γ-Fe 2 O 3 /BCN) is developed. The catalyst shows a Faradaic efficiency of 95% (at −0.59 V vs RHE) and yield rate of 7570 μg h –1 mg cat –1 (at −0.64 V vs RHE) of ammonia. The γ-Fe 2 O 3 /BCN catalyst also exhibits long-term stability in cyclic tests. The computational studies reveal that the charge transfer between γ-Fe 2 O 3 and BCN in γ-Fe 2 O 3 /BCN has a critical role in enhancing the catalytic activity as compared to γ-Fe 2 O 3 and BCN.