Investigation on structural, dielectric and ferroelectric properties of samarium-substituted BiFeO3–PbTiO3 composites

Abstract

The polycrystalline samples of 0.8BiSmxFe1−xO3–0.2PbTiO3 (x=0.05,0.10,0.15 and 0.20) were prepared by using the conventional solid-state reaction technique and sintered at high temperature (850∘C). X-ray diffraction (XRD) confirms the distorted rhombohedral crystal structure for all the composites at room temperature. The surface morphology was checked by field-emission scanning electron microscope (FESEM) technique and homogeneous mixing of the components was confirmed by energy-dispersive analysis of X-ray (EDAX). The detailed study of dielectric properties of the composites reveals an increasing nature of dielectric constant (εr) and loss tangent (tanδ) with the increase of temperature due to thermal activation. The Arrhenius plots of temperature dependence of AC conductivity yield the activation energy within the material at high-temperature range. The ferroelectric study shows that the remnant polarization decreases with the increase of Samarium (Sm) concentration.

Keywords

• X-ray diffraction
• composite materials
• dielectric materials
• ferroelectricity