Macroporous NiMo alloy self-supporting electrodes for efficient hydrogen evolution at ultrahigh current densities

Abstract

With the aim of the rational design of industrial electrocatalysts working at high current densities over 100 mA cm⁻² toward electrochemical water splitting, in this paper, we proposed a strategy to prepare porous arrays of NiMo alloy based hydrogen evolution reaction (HER) electrodes with high activity and good stability using the combination of the hard template method and electrodeposition technology, which showed high intrinsic activity, rapid mass transfer due to the structure of multi-scale pores and super-wetting surfaces ensuring the timely removal of evolved H₂ bubbles. The as-obtained electrodes can provide a high current density up to 500 and 1000 mA cm⁻² at overpotentials of 306 and 491 mV, respectively in 1.0 M KOH. Our study makes it possible to design alloy HER electrodes with high activity and stability working at an industrial scale of current density and promotes the development of a hydrogen economy resulting from electrochemical water splitting.