Study of multiferroic properties of Mn substituted Bi0.8Sm0.1Dy0.1Fe1−xMnxO3 ceramics

Abstract

Transition metal Mn substituted various multiferroic Bi _0.8 Sm _0.1 Dy _0.1 Fe _1 _-x Mn _x O _3 ( x = 0.00, 0.01, 0.03 and 0.05) ceramics samples were fabricated by the solid-state reaction technique. The distorted rhombohedral perovskite structure with some phase impurity of all samples is confirmed by x-ray diffraction analysis. Field Emission Scanning Electron Microscope and Energy Dispersive x-ray spectroscopy are used for microstructural and quantitative analysis, respectively. Densities are decreased and the average grain size is increased with Mn contents. The initial permeability and relative quality factor ( RQF ) have found to be increased with Mn contents in the samples. The peaks in RQF shifts toward the lower frequency region with increasing Mn contents can be attributed by Snoek’s relation. All the samples show paramagnetic behavior at room temperature and magnetization slightly increases with Mn contents. The frequency dependent dielectric constant is investigated and found to consequence of space charge polarization. The dispersion behavior in dielectric constants can be explained by the Maxwell–Wagner model. The dielectric constants and dielectric loss decrease with increasing of Mn contents for all the samples. The value of electric modulus is found to increases with the increasing of frequency and this dispersion phenomena is due to short range mobility of charge carriers in conduction. The effect of grain and grain boundaries on electric properties of samples are investigated by complex impedance analysis. The ac conductivity increases with frequency due to small polaron hopping and it can be attributed according to Jonscher’s power law.

Keywords

• structural properties
• magnetic properties
• modulus study
• impedance study relative quality factor