Dual NiFe₂O₄//CoFe₂O₄ nanosheets compound dynamism for supercharged supercapacitors

Amid the energy crisis, intensive research is underway to develop advanced energy storage devices, vital for diverse applications. These solutions bolster productivity, portability, and grid stability, fostering a transition toward a sustainable energy landscape across consumer and industrial sectors. This study focuses on the synthesis of NiFe₂O₄//CoFe₂O₄ nanosheets composites for high-performance supercapacitor electrodes, utilizing recent advancements in materials science. Employing a simple hydrothermal process, we successfully fabricated nanosheets composite materials in a step-by-step manner for the first time. The resulting nanohybrid underwent comprehensive physicochemical characterizations, including X-ray diffraction, nitrogen adsorption–desorption, X-ray photoelectron spectrometer, High-resolution transmission electron microscopy, and Field Emission Scanning Electron Microscopy analyses, elucidating its morphology, structure, and chemical composition. Our unique electrode material exhibited an impressive specific capacitance of 800 Fg⁻¹ at a current density of 2 Ag⁻¹ in a potassium hydroxide electrolyte with the surface area 75 m²/g. Furthermore, it demonstrated excellent cycling stability, retaining 85.9 % capacitance after 10,000 cycles at a current density of 1 Ag⁻¹, with low charge-transfer resistance and exceptional rate capability. The distinctive heterostructure entities, abundant electroactive sites, and synergistic interfacial interactions contributed to its superior electrochemical energy storage properties. Insights into the plausible electrochemical reactions underlying the working mechanism of these nanosheets materials are provided. Overall, our findings underscore the potential of NiFe₂O₄//CoFe₂O₄ nanosheets as electrode materials for efficient energy storage applications.