ESTIMATION OF CATION DISTRIBUTION, OPTICAL AND LECTRICAL PROPERTIES OF NiFe2O4 AND Ni0.875 Mg0.075Cu0.05Fe2O4 FERRITE MATERIALS

Abstract

In the present study, NiFe2O4 and Ni0.875Mg0.075Cu0.05Fe2O4 ferrite materials were successfully synthesized by solid state reaction method. The thermal property, structure, electrical and dielectric properties of both ferrites were investigated by Thermogravimetric analysis (TGA), Differential thermal analysis (DTA), X-ray powder diffraction (XRD), Ultraviolet visible (UV-vis) spectroscopy and Impedance spectroscopy (IS). The XRD analysis revealed that both the synthesized samples have cubic spinel structure with Fd3m space groups. From XRD results, different structural parameters, such as the cation distribution, the lattice parameters, crystal size, unite cell volume of NiFe2O4 and Ni0.875Mg0.075Cu0.05Fe2O4 ferrites were also estimated. The crystallite sizes of NiFe2O4 and Ni0.875Mg0.075Cu0.05Fe2O4 sample were determined from the maximum intensive diffraction peak of the (311) by using Debye-Scherrer’s formula which gave 22.16 nm and 24.82 nm respectively. This confirms the nano crystalline nature of both synthesized ferrites. The optical bandgap of both ferrites was also calculated using UV-Vis spectroscopy measurements and it was found in the values of 2.73 eV and 2.75 eV for NiFe2O4 and Ni0.875Mg0.075Cu0.05Fe2O4 ferrites, respectively. From the electrical and dielectric properties studies, it was found that the value of the dielectric constant as well as the real impendence

of both samples decrease exponentially with an increasing frequency indicating normal Maxwell-Wagner type dielectric dispersion due to interfacial polarization.