Structural and electrochemical investigation on pure and nickel doped cobalt ferrite nanoparticles for supercapacitor application

Abstract

Hydrothermal method was employed for the synthesis of pure Cobalt ferrite and Nickel doped Cobalt ferrite nanoparticles. The crystallinity, morphological and the electrochemical investigation of the prepared samples were studied using X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM), FT-IR and Cyclic voltammetry (CV) study analysis. The cubic spinel crystal structure was revealed by the XRD pattern. The average crystallite size for the pure cobalt ferrite and the nickel doped cobalt ferrite doped samples were 20 nm and 25 nm respectively. The lattice constant of the pure and the doped samples were 8.29 Å and 8.36 Å respectively. SEM analysis revealed the presence of nanoclusters. The EDS patterns confirmed the presence of the elements Ni, Co, Fe and O without any impurity. The infra-red spectra showed the features of higher and lower energy bands corresponding to tetrahedral (T-band) and the presence of octahedral (O-band) complexes confirmed the creation of spinel ferrites. The electrochemical behavior of the prepared nanoparticles was investigated through Cyclic Voltammetry (CV) study analysis using 2 M of KOH electrolyte solution. The potential window was limited as 0 V to 0.6 V at various scan rates 10, 30, 50, 80 and 100 mV/s. Cyclic Voltammetry study revealed that the Nickel dopant increased the specific capacitance than the pure Cobalt ferrite. The specific capacitance of the pure cobalt ferrite and the nickel doped cobalt ferrite samples were obtained as 517 F/g and 561 F/g respectively.