Sequentially Pitting-Grown Engineering on Ni Foam to Fabricate Vertical MnFeNi Hydroxide Arrays as a Facile-to-Prepare Catalyst with Ultralong Lifetime for Oxygen Evolution Reaction

Exploring efficient and highly stable oxygen evolution catalysts is very important for hydrogen production by water electrolysis. Herein, we report a synthetic method with a simple two-step room-temperature immersion, which offers MnFeNi hydroxide catalysts with an underbrush-like structure on nickel foam (NF). This synthesis on Ni foam can be accomplished in minutes, while the prepared catalyst has shown an ultralong lifetime of over 1500 h for catalyzing the oxygen evolution reaction (OER). Specifically, the MnFeNi hydroxide catalyst requires the overpotential of only 230 and 250 mV at the current density of 100 and 500 mA·cm–2for OER, respectively. This work provides a cost-effective surface engineering method to convert commercial NF into a powerful OER catalyst in alkaline water electrolysis.