A MOF‐Derived CoFe 2 O 4 /NiS 2 Hierarchical Electrode on Carbon Cloth for Efficient Overall Water Splitting

ABSTRACT Developing efficient and robust electrocatalysts for the hydrogen evolution reaction (HER) is essential for advancing water‐splitting technologies. Herein, we synthesized the CoFe 2 O 4 /NiS 2 ‐MOF/CC (carbon cloth) composite by first growing a Co‐MOF scaffold in situ on carbon cloth (CC) to form a three‐dimensional (3D) porous scaffold, which was then subjected to a one‐step hydrothermal sulfurization for anchoring CoFe 2 O 4 and NiS 2 . The 3D Co‐MOF/CC scaffold affords a high specific surface area and open porosity, exposing abundant active sites and significantly enhancing HER electrocatalysis. Under hydrothermal sulfurization at 180°C and an Fe:Ni molar ratio of 1:1, the resulting 3D catalyst delivers excellent HER and OER activity in 1 M KOH, with low overpotentials of 94 mV at 10 mA·cm −2 for HER and 291 mV at 50 mA·cm −2 for OER. It also delivers stable overall water splitting for 22 h at a cell voltage of 1.58 V at 10 mA·cm −2 , showing competitive performance among recently reported MOF‐based and MOF‐derived electrocatalysts. Hence, this work demonstrates a cost‐effective route to high‐performance, bifunctional catalysts for overall water splitting.