A Molecular Approach to Manganese Nitride Acting as a High Performance Electrocatalyst in the Oxygen Evolution Reaction

Abstract

Abstract The scalable synthesis of phase‐pure crystalline manganese nitride (Mn 3 N 2 ) from a molecular precursor is reported. It acts as a superiorly active and durable electrocatalyst in the oxygen evolution reaction (OER) from water under alkaline conditions. While electrophoretically deposited Mn 3 N 2 on fluorine tin oxide (FTO) requires an overpotential of 390 mV, the latter is substantially decreased to merely 270 mV on nickel foam (NF) at a current density of 10 mA cm −2 with a durability of weeks. The high performance of this material is due to the rapid transformation of manganese sites at the surface of Mn 3 N 2 into an amorphous active MnO x overlayer under operation conditions intimately connected with metallic Mn 3 N 2 , which increases the charge transfer from the active catalyst surface to the electrode substrates and thus outperforms the electrocatalytic activity in comparison to solely MnO x ‐based OER catalysts.