MAGNETIC AND DIELECTRIC PROPERTIES OF COXZN1-XFE2O4 SYNTHESIZED BY METALLO-ORGANIC DECOMPOSITION TECHNIQUE

Cobalt doped Zinc ferrites, CoxZn1-xFe2O4, (x = 0, 0.2, 0.4, and 0.6) were prepared by chemical solution method using metallo-organic precursors. The crystalline structure, microstructure, magnetic and dielectric properties of the samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM) and impedance analyser respectively. All samples show cubic spinel structure with minor Fe2O3 phase and lattice parameter decreases from 8.419 to 8.308 with increasing cobalt content from 0 to 60%. Magnetic measurement shows that CoxZn1-xFe2O4 samples exhibit ferromagnetic behavior at room temperature. The saturation magnetization initially increases from 2.17 to 71.2emu/g on increasing Co content to 40% and then decreases to value 55.9emu/g at Co concentration of 60%. The coercivity also increases to Hc ~ 330Oe for the sample with Co=20% and then decreases to minimum value of Hc ~ 32Oe for sample having 40% Co content. The coercivity value is then increases and is measured as Hc ~ 154Oe for sample with 60% Co content. The magnetic properties are explained in terms of cation distribution and grain size effect. The dielectric properties of the samples were studied with varying temperature and frequencies. The dielectric properties are influenced by electron hopping mechanism between Fe2+ and Fe3+ ions.