MOF derived Fe3O4/NiO decorated rGO-BN for efficient electrochemical water splitting

Abstract

Water electrolysis is recognized as a most promising strategy for clean energy production. Hence, it requires an earth-abundant, well-stable, and highly efficient electrocatalyst for excellent electrocatalytic performance. In this study, a Fe₃O₄/NiO composite on an rGO-BN matrix is developed. The Fe₃O₄/NiO derived from MOF enhances the electrocatalytic activity by lowering the overpotential for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The rGO-BN (rB) matrix provides stable support for Fe₃O₄/NiO and Fe₃O₄/NiO nanoparticles are distributed throughout the rGO-BN sheet structure. The developed electrocatalyst delivered a lower overpotential of 117 mV for HER and 208 mV for OER to reach 10 mA cm⁻². The lower Tafel slope, higher turnover frequency (TOF), and lower overpotential enhanced the electrocatalytic activity. In addition, the enhanced electrochemical active surface area and low R_ct value confirm the electrocatalyst ability to split water excellently. The stability of the electrocatalyst was studied by the LSV performance before and after 5000 CV cycles, confirming the durability of the electrocatalyst in both HER and OER. An overall water-splitting study was conducted and exhibited a cell potential of 1.81 V at 10 mA cm⁻². This study may help design and fabricate excellent and efficient electrode materials for electrochemical water splitting.