Investigating the effect of multiple grain-grain interfaces on electric and magnetic properties of [50 wt% BaFe12O19-50 wt% Na0.5Bi0.5TiO3] composite system

Abstract

This report presents the fabrication, electrical properties along with the magnetic parameters of a composite system considering a strong ferrimagnetic (BaFe12O19) and a ferroelectric (Nao(5)Bi(0.5)TiO(3)) material. Polycrystalline 50 wt% BaFe12O19 (BaM)-50 wt% Nao(5)Bi(0.5)TiO(3) (NBT) composite system was prepared by the solid state reaction method. Rietveld refinement of XRD pattern confirms the presence of BaM and NBT phases without any impurity phase. From scanning electron micrograph both the phases are also clearly identified. In this report, the electric relaxation and conductivity properties were systematically investigated and analyzed in the frequency range of 100 Hz to 1 MHz and temperature range of 30-200 degrees C. The presence of different type of grains and significant reduction in the resistance of the composite system were found to be responsible for the nature of electric relaxation behavior. A peculiar and interesting evolution of grain boundary conduction was detected which was argued due to the existence of three possible grain boundaries such as: (i) BaM-BaM interface, (ii) NBT-NBT interface and (iii) BaM-NBT interface. The magnetization study (M-H loop) paves that, the saturation magnetization and coercive field reduces for composite system. (C) 2016 Elsevier B.V. All rights reserved.