Influence of Cu2+ substitution on structural and optical properties of Mg-Zn ferrite nanoparticles

Abstract

The Cu2+ doped CuxMg0.5Zn0.5-xFe2O4 [x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5] ferrite nanoparticles were synthesized by co-precipitation method using oxalate precipitant. The synthesized oxalate precursors have been characterized by Elemental analysis, FT-IR and Thermogravimetry. The structural and optical properties of final ferrite samples have been investigated by X-ray diffraction (XRD), Fourier Transform Infra-Red spectroscopy (FT-IR) and UV–Vis Diffuse Reflectance Spectroscopy. The XRD patterns reveals no additional peaks due to second phase i.e. single phase cubic Cu-Mg-Zn ferrites nanoparticles are formed. The parameters like theoretical and experimental lattice constant, crystallite size, X-ray density and unit cell volume extracted from XRD data. It is noticed that with increasing Cu2+ doping lattice parameter and unit cell volume are decreased while X-ray densities are increased. The interionic distances like ionic radii, bond lengths, hopping lengths and anion-anion distance were also evaluated. FT-IR spectra exhibit two distinct absorption bands in the range of 568–589 cm−1 and 448–461 cm−1 which are characteristic of ferrite. Different force constants and Debye temperature for synthesized samples found in agreement with literature. The absorption spectra and Energy band gaps are evaluated by using UV–Vis DRS. The energy band gaps Cu-Mg-Zn ferrites found in the range of 1.643 eV–1.557 eV. UV–Vis DRS analysis showed that the band gap energy decreases with increasing Cu2+ doping.