Mn3O4 Nanocube: An Efficient Electrocatalyst Toward Artificial N2 Fixation to NH3

Abstract Traditionally, ammonia (NH3) is synthesized via the Haber–Bosch process, which is not only commanded by harsh conditions but causes serious environmental pollution. Electrochemical reduction is recognized as a mild and environmentally benign alternative approach for NH3 synthesis, but an efficient electrocatalyst is a prerequisite for NH3 production. In this communication, the first experimental demonstration that Mn3O4 nanocubes can be used as an efficient non‐noble‐metal electrocatalyst for N2 reduction reaction (NRR) at ambient conditions is reported. In 0.1 m Na2SO4 aqueous solution, the catalyst delivers excellent NRR activity with an NH3 yield of 11.6 µg h−1 mg−1cat. and Faradaic efficiency of 3.0% at −0.8 V versus reversible hydrogen electrode. Notably, this catalyst also possesses satisfactory durability during the electrolysis and recycling test.