Influence of the doping of Ti4+ ions on electrical and magnetic properties of Mn1+xFe2-2xTixO4 ferrite

Abstract

ac conductivity and magnetic behaviour have been studied for a series of polycrystalline ferrite with general formula Mn1-xFe2-2xTixO4, (0 ≤ x ≤ 0.5), prepared using a conventional solid-state reaction technique. The results of ac conductivity show that σac increases as the frequency and the temperature increase; whereas it decreases as Ti content increases except for a sample x = 0.1. The values of activation energies Ef for conduction process are determined from Arrhenius plots, and the variations of these activation energies as a function of composition have been discussed. The conduction mechanism used in present study have been discussed in the light of electron exchange between Fe2 and Fe3 ions and hole hopping between Mn+3 and Mn+2 ions at the octahedral B-sites. It observed that the saturation magnetization decreases with increase Ti4+ substitution, which is explained by the weakening of the exchange in the system according to Neel's molecular field model. © 2008 Elsevier B.V. All rights reserved.