Large-Scale Preparation of Ultrathin Bimetallic Nickel Iron Sulfides Branch Nanoflake Arrays for Enhanced Hydrogen Evolution Reaction

Developing the large-scale preparation of non-noble metal catalysts with high performance is crucial for promoting electrochemical production hydrogen from water. In this work, a novel TiO2@FeNi2S4 (TiO2@FNS) branch nanoflake array on Ni foam can be prepared at large scale (50 cm2) by combining an atomic-layer-deposited (ALD) TiO2 skeleton one-step facile low-temperature (<100 °C) sulfurization method. As-prepared TiO2@FNS arrays exhibit excellent evolution reaction (HER) overpotential 97 mV 10 mA cm−2, superior to FNS counterpart (without coating) and other reported catalysts. The enhanced HER catalytic attributed increased specific surface area improved structural stability due introduction coating. Moreover, theoretical calculations also show that bimetallic NFS structure more favorable dissociation water molecule desorption H than monometallic Ni3S2 counterpart. With combination experimental results calculations, work has enlightened new way exploring high-efficient HER.