Electrodeposited nanostructured CoFe₂O₄ for overall water splitting and supercapacitor applications

To contribute to solving global energy problems, a multifunctional CoFe₂O₄ spinel was synthesized and used as a catalyst for overall water splitting and as an electrode material for supercapacitors. The ultra-fast one-step electrodeposition of CoFe₂O₄ over conducting substrates provides an economic pathway to high-performance energy devices. Electrodeposited CoFe₂O₄ on Ni-foam showed a low overpotential of 270 mV and a Tafel slope of 31 mV/dec. The results indicated a higher conductivity for electrodeposited compared with dip-coated CoFe₂O₄ with enhanced device performance. Moreover, bending and chronoamperometry studies suggest excellent durability of the catalytic electrode for long-term use. The energy storage behavior of CoFe₂O₄ showed high specific capacitance of 768 F/g at a current density of 0.5 A/g and maintained about 80% retention after 10,000 cycles. These results demonstrate the competitiveness and multifunctional applicability of the CoFe₂O₄ spinel to be used for energy generation and storage devices.