A MOF-derived Co3O4/Ni–Co sulphide heterojunction for ultra-stable sulphur oxidation

Abstract

The thermodynamically favourable sulphur oxidation reaction (SOR) promises energy-efficient H₂ production, but its practical deployment is severely hindered by rapid anode deactivation via sulphur passivation. Herein, we report a robust hierarchical heterostructure comprising Ni–Co sulphide nanosheets anchored on a ZIF-L-derived porous Co₃O₄ scaffold (Co₃O₄/NCS), which successfully surmounts this stability challenge. By establishing a strong structure–property correlation, we demonstrate that the conductive Co₃O₄ backbone not only provides mechanical stability but also dynamically modulates the electronic structure of the active sulphide phase to optimize intermediate adsorption. Consequently, the Co₃O₄/NCS electrode delivers exceptional SOR activity, achieving a current density of 100 mA cm⁻² at a remarkably low potential of 0.303 V vs. RHE. Crucially, it demonstrates an extraordinary operational lifetime exceeding 300 hours, significantly outperforming state-of-the-art catalysts. This work provides a highly effective oxide/sulphide interfacial design strategy to prevent sulphur passivation for sustainable energy conversion.