COMPARATIVE STUDY OF STRUCTURAL, OPTICAL AND ELECTRICAL BEHAVIOR OF PURE AND NICKEL-COPPER SUBSTITUTED CADMIUM NANO-FERRITE

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.