NiFe2O4/SiO2 nanostructures as a potential electrode material for high rated supercapacitors

Abstract Engineered materials are crucial for the higher efficiency of supercapacitors. Current work presents roughly shaped spherical NiFe2O4 nanoparticles dispersed in the SiO2 matrix NiFe2O4/SiO2 as a newfangled electrode material for supercapacitors with remarkable performance. Designing the NiFe2O4/SiO2 nanostructure with a sol-gel method followed by the Stober method to grow silica has instigated NiFe2O4/SiO2 as dynamic material with higher electrochemical activity. Physicochemical aspects of NiFe2O4/SiO2 nanostructures are evaluated using Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy analysis. The electrochemical activity is evaluated by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) representing the comparable efficiency and reversibility of the electrode materials. The prepared electrode shows a capacitance of 925 F/g (154.1 mAh/g or 555 C/g) at 1 A/g, with 95.5% capacitance retention after 5000 cycles at 20 mA/cm2. The improved electrochemical performance of the NiFe2O4/SiO2 electrode can be subjected to prompt diffusion process provided by NiFe2O4/SiO2 and enhanced redox reactions owing to the high surface area. The mentioned features decrease the total impedance of the electrodes as suggested by electrochemical impedance spectroscopy (EIS).