The dual synergistic effects of Co3O4-rGO in constructing NiFe-LDH@Co3O4-rGO/NF for the enhanced oxygen evolution

Abstract

Exploring high-activity NiFe-LDH catalysts is crucial for producing hydrogen and oxygen via water splitting. Nonetheless, the insufficient conductivity and inferior activity of NiFe-LDH hinder the improvement of water-splitting efficiency. This study successfully developed a transition layer comprising Co₃O₄ nanosheets and rGO on nickel foam (Co₃O₄-rGO/NF) via a one-pot mild hydrothermal route, serving as a framework in constructing the NiFe-LDH@Co₃O₄-rGO/NF. Co₃O₄-rGO interlayer not only creates an open framework to enhance conductivity and enrich active sites of NiFe-LDH but also leverages electronic synergies between NiFe-LDH and Co₃O₄ to modulate electronic states of catalysts, thus boosting the inherent activity for OER. The designed catalyst shows impressive OER performance, featuring an overpotential of just 249 mV at 50 mA cm⁻² and a Tafel slope of 39.3 mV dec⁻¹. The findings provide a simple and dual-effect substrate modification approach for optimizing NiFe-based electrocatalysts to improve water electrolysis.