Electrochemical properties of CoFe2O4 nanoparticles and its rGO composite for supercapacitor

Cost-effective solutions for improved performance, activity, and stability are the main concern for the development of energy-storage devices. Generally, reduced graphene oxide (rGO) supported cobalt ferrite (CoF) based electrodes possesses enhanced electrochemical properties in supercapacitor applications such as high specific capacitance (C-S) and long cyclic stability due to the presence of multiple oxidation states of cobalt ions, high surface area, and porous nanostructure that enables fast ion-diffusion. Herein, we report a one-pot solvothermal synthesis of glycol functionalised CoF nanoparticles and the composite with rGO for the supercapacitor electrode. Further, bare CoF was annealed at 300 and 500 degrees C to evaluate the dependency glycol functionalization on the electrochemical behaviour. The CoF-rGO nanocomposites in alkaline (2 M KOH) electrolyte exhibit better electrochemical behaviour compared to bare and annealed CoF. CoF-rGO exhibits high C-S of 551 F/g at a scan rate of 2 mV/s with 98% capacitance retention after 2000 cycles. The power law and Trasatti method provide a qualitative analysis of the diffusivity of the nanoparticles at the electrode/electrolyte interface.