Abstract:
In recent years, the synthesis of Nano crystalline ferrite materials has the focus of the
intense fundamental and applied research with special emphasis on their enhanced
electrical and magnetic properties that are different from those of ferrites in the form of
bulk size. Considering this, the Nano crystalline CdFe2O4 and Cd0.85Ni0.075Cu0.075Fe2O4
ferrites was synthesized by sol-gel method. The comparative study of both ferrites on
structural, optical and electrical behavior was investigated using thermogravimetric
analysis (TGA), differential thermal analysis (DTA), the x-ray powder diffraction (XRD),
scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS),
Ultraviolet visible spectroscopy (Uv), impedance spectroscopy (IS) characterization
techniques.
From TGA/DTA analysis, it was identified the complete crystal formation of CdFe2O4
and Cd0.85Ni0.075Cu0.075Fe2O4 ferrites. The XRD analysis confirms that CdFe2O4 and
Cd0.85Ni0.075Cu0.075Fe2O4 ferrites synthesized by sol-gel belong to a cubic spinel structure
with space group of Fd3m. It was also observed that the substitution of Ni
+2
and Cu+2
ions for Cd2+
ions result in decrease lattice parameter which has led to decrease in unit
cell volume and crystal size of CdFe2O4. Moreover, different structural parameters, such
as the x-ray density, bulk density, surface area, porosity of both ferrites were estimated.
The SEM analysis revealed that smaller grain sizes are observed for
Cd0.85Ni0.075Cu0.075Fe2O4 ferrite sample. This is consistent with the obtained smaller
crystal size and lattice parameter. The EDS analysis showed that all the elements are
incorporated in the lattice of both CdFe2O4 and Cd0.85Ni0.075Cu0.075Fe2O4 samples. No
other elements are detected in both samples. From UV-vis spectroscopy study, the optical
band gap was found to be 2.7 eV for CdFe2O4 ferrite and 3.02eV for
Cd0.85Ni0.075Cu0.075Fe2O4 ferrite. The variations of the real and imaginary impedance as
well as dielectric constant as a function of frequency for both synthesized ferrites were
also investigated in this study.
