Investigation of structural, dielectric, impedance and magnetic properties of BiFe1-xInxO3 (0.0 ≤ x ≤ 0.6) ceramics

Abstract

Indium substituted BiFe1-xInxO3 (x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6) ceramics were synthesised via solid reactions method. The samples’ microstructure, dielectric, electrical and magnetic properties were investigated by X-rays diffractions (XRD), scanning electron microscopy (SEM), dielectric analyser, electrometer and vibrating sample magnetometer (VSM). From XRD, pristine BFO sample exhibited single phase rhombohedral crystal structure, space group R3c 161. Introduction of In+3 into BFO matrix promoted the growth of BiInO3 and Bi25FeO40 phases, however, BFO remained the dominant phase up to x = 0.4. Form SEM results, BFO exhibited large homogeneous grain morphology with average grain size 2.04 µm, that get distorted, decreased with introduction of In+3. From magnetic analysis, pure BFO showed antiferromagnetic behaviour while weak ferromagnetic was observed with In3+ substitution. The highest magnetisation 0.04 emu/g and magnetic remanence 6.22 × 10−4 emu/g were recorded for sample x = 0.3. Dielectric measurement showed increasing of dielectric constant εʹr from 26.5 for pure BFO to 372 for sample x = 0.6. The leakage current density was reduced with x from 9.24 × 10−4 A/cm2 for pure BFO to 9.8 × 10−7 for sample x = 0.6. A/cm2. Impedance spectroscopy and dielectric modulus were used to further understand the dielectric behaviour of the samples and the relevant results were analysed and discussed in detail.

Keywords

• BiFeO3
• BiInO3
• Composite microstructure
• Dielectric constant
• Leakage current
• Weak ferromagnetic