Analysis of temperature and frequency dependent dielectric properties, dynamic hysteresis loop and thermal energy conversion in BaZr0.05Ti0.95O3 ceramic

Abstract

The barium zirconium titanate ceramic with formula BaZr0.05Ti0.95O3 has been synthesized by the conventional solid state reaction technique. The synthesized ceramic sample is characterized by X-ray diffraction, scanning electron microscopy, Raman spectroscopy, temperature dependent dielectric spectroscopy and ferroelectric behaviour. The Raman spectrum confirms the orthorhombic structure at room temperature and local distortions due to distorted octahedral structures. The temperature dependent dielectric study reveals the occurrence of three transition temperatures representing rhombohedra to orthorhombic, orthorhombic to tetragonal and tetragonal to cubic transition in the material. The area of the hysteresis loop decreases with temperature up to the transition temperature, followed by an increase at higher temperatures. Scaling relations for coercive field (Ec) and remnant polarization (Pr) are studied as a function of temperature. This exhibits back-switching polarization behaviour as a function of temperature. The thermal energy conversion potential of the studied sample is obtained by using Olsen cycle.