Reaction time-driven structural and electrochemical analysis of MnFe2O4 for solid-state supercapacitor application

This study synthesizes manganese ferrite (MF) using a low-cost hydrothermal method. During synthesis, hydrothermal reaction time is varied to monitor the morphological changes and their effects on electrochemical performance. Morphological study demonstrates that ions are effectively transported via strongly interconnected nanostructures. The MF electrodes undergo electrochemical characterizations using different techniques. The MF24 electrode shows a specific capacitance of 603.68 F/g at 2 mA/cm² under optimized conditions. To comprehend the dynamics of charge storage for the MF24 electrode, the electrochemical kinetics are evaluated, which show the dominance of diffusion contribution. The MF24 electrode shows an 89.91 % capacitance retention after 5000 cycles. Furthermore, a solid-state symmetric supercapacitor device (SSD) with a potential window of 1 V is tested. At 20 mA/cm², the MF24//MF24 SSD device demonstrates an energy density and power density of 10.16 Wh/kg and 2439.02 W/kg. The results indicate that including this synergy of metal ferrite can enhance the performance of supercapacitors.