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.
