Investigation of cerium NiZn ferrites on cationic distribution in superparamagnetic behavior and its electrochemical performance for pseudocapacitors

The ferrite materials are emerging as a promising material to overcome the global energy crisis. To address these issues a new series of cerium (Ce+3) substituted nickel zinc ferrites with general formula of Ni0.5Zn0.5CexFe2-xO4(x = 0, 0.02, 0.04, 0.06, 0.08 and 0.1) has been fabricated employing solgel auto combustion technique. The urea and glycine are used as reducing agents and sintered at 1000 °C for 4 h. The structural, optical, dielectric, magnetic and electrochemical properties have been evaluated using X-ray diffractometer (XRD), UV–Visible spectroscopy, Inductor Capacitor Resister (LCR) meter, Vibrating Sample Magnetometer (VSM), Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) techniques respectively. The structural analysis reveals the formation of single-phase cubic spinel structure. The optical analysis shows the absorption peak arises in ultraviolet (UV) region. The dielectric study at room temperature reveals the significant changes in dielectric constant, tangent loss and AC conductivity with increasing frequency and Ce+3concentration. The investigation of magnetic behavior shows the superparamagnetic behavior of all the samples. The saturation magnetization decreases and coercivity varies with the addition of Ce+3. The specific capacitance (Csp) of prepared electrodes increases with increasing Ce concentration. The highest Cspis obtained at x = 0.1 which is ~2056.9 Fg−1at the lowest scan rate of 5 mV/s. The pseudocapacitive contribution of the sample at x = 0.1 is 94.49 % at scan rate of 5 mV/s. Hence these electrodes may be suggested as a promising candidate for supercapacitor. This study is unraveling a new tactic for improving the energy storage properties of a given material.