Effect of cation distribution and temperature variation on magnetic and dielectric properties of manganese substituted cobalt ferrites

Abstract

Bulk samples of Co1-xMnxFe2O4 (x = 0, 0.05 and 0.10) were synthesized in single phase form by using sol-gel technique. All samples undergo ferrimagnetic transition which decrease from 778 K to 766 K with increase in Mn substitution. The initial magnetization data measured at room temperature were interpreted using the Law of Approach to Saturation. The magnetocrystalline anisotropy constant and saturation magnetization showed increase in value for 5 at.% of Mn concentration.The variation of coercive field was interpreted in terms of microstructural parameter. The complex impedance spectroscopic data showed the charge carrier relaxes over the grains and grain boundaries with relaxation energy of the order of 10−1 eV. Equivalent circuits corresponding to the Nyquist plots were obtained from Zsimpwin software. The ac conductivity was studied by using Jonscher Power Law and it was established that small polaron model governs the mechanism of electrical conductivity.