Preparation of novel (Sb1/2Na1/2)(Fe2/3W1/3)O3 compound by solid state reaction technique and their multiferroic property

Abstract

Large leakage current and poor magnetizations are the two major shortcomings observed in known multiferroic BiFeO3 which hinders its practical utility. Na and W co-doped SbFeO3 i.e. (Sb1/2Na1/2)(Fe2/3W1/3)O3 with enhanced electric and magnetic properties compared to BiFeO3 is prepared by solid state reaction technique. To understand the structure of the compound, X-ray diffraction analysis has been carried out which shows its orthorhombic crystal structure with crystallite size of 20 nm. The obtained crystallite size is same as the particle size, calculated by transmission electron microscope. The scanning electron microscope analysis reveals the formation of grain and grain boundary of the compound with average grain size of 108 nm. Energy dispersive X-ray spectroscopy studies shows that the elemental composition of the compound before and after heat treatment process is almost same. Dielectric and impedance study of the material in a wide range of temperature (30–400 °C) at different frequencies (100 Hz–1 MHz) shows the dielectric relaxation phenomena and the properties of grain and grain boundary respectively. It also reveals the non-Debye type relaxation and negative temperature coefficient of resistance (NTCR) behavior of the compound. DC conductivity of the material is found to obey Arrhenius relation whereas ac conductivity is governed by Jonscher’s universal power law. The appearance of room temperature P–E loop shows the ferroelectric nature of the compound. The material shows the weak ferromagnetic property with remnant magnetization (Mr) of 0.00582 emu/g and coercive field (Hc) of 369 Oe.