One‐Pot Hydrothermal Synthesis of Ni 3 S 2 /MoS 2 /FeOOH Hierarchical Microspheres on Ni Foam as a High‐Efficiency and Durable Dual‐Function Electrocatalyst for Overall Water Splitting

Electrochemical water splitting is a valid way for production of the pollution‐free, cost‐effective and sustainable hydrogen energy. Herein, Ni 3 S 2 /MoS 2 /FeOOH hierarchical microspheres constructed by nanobelt building blocks were directly grown on Ni foam via a simple one‐pot hydrothermal approach. Benefitting from the synergistic effect of these components as well as the unique hierarchical microsphere structure, Ni 3 S 2 /MoS 2 /FeOOH exhibits superior dual‐function electrocatalytic activity for water splitting in 1.0 M KOH, with low overpotentials of 219 mV for OER at 100 mA cm −2 and 76 mV for HER at 10 mA cm −2 . The electrolyzer based on the Ni 3 S 2 /MoS 2 /FeOOH electrodes only needs a low cell voltage of 1.52 V to drive water splitting at 10 mA cm −2 , which is comparable to the state‐of‐the‐art Pt−C||IrO 2 couple (1.50 V). The cost‐efficient and high‐performance Ni 3 S 2 /MoS 2 /FeOOH bifunctional electrocatalyst developed in this work exhibits a potential application prospect in industrial hydrogen production.