Co 9 S 8 ‐Ni 3 S 2 @CoFe LDH/NF Heterostructure as an Efficient Electrocatalyst for Enhanced Oxygen Evolution Performance

ABSTRACT Exploring efficient, stable, and earth‐abundant electrocatalysts toward the oxygen evolution reaction (OER) is a central theme for realizing industrial application of water splitting. In this study, a 1D@2D heterostructure of Co 9 S 8 ‐Ni 3 S 2 @CoFe LDH/NF is constructed via hydrothermal and electrodeposition approaches, where ultrathin CoFe LDH nanosheets are interconnected and deposited onto Co 9 S 8 ‐Ni 3 S 2 nanorod arrays. This 1D@2D microstructure benefits from the exposure of a large number of accessible reactive sites. The strong interaction between the sulfide hybrid and LDH material could modulate the electronic structure of Co 9 S 8 ‐Ni 3 S 2 @CoFe LDH and generate a high concentration of high‐valence metal sites. As a result, the optimal catalyst exhibits superior OER performance with a low overpotential of 189 mV at 10 mA cm −2 , a small Tafel slope of 30.22 mV dec −1 , and good stability in alkaline solution. This work opens up a possibility for obtaining efficient and cost‐effective electrocatalysts for clean energy production through water splitting.