Investigation of structural and conduction mechanism of Europium modified BaZr0.05Ti0.95O3 ceramic prepared by solid-state reaction method

Abstract

The possibility of tuning and improving the electrical properties of Perovskite materials is essential for highlighting their industrial applications. In this work, the impact of substituting Europium at Ba-sites in BaZr0.05Ti0.95O3 ceramic is reported preferably in the light of structural, microstructural and conduction behavior. The Eu doped BaZr0.05Ti0.95O3 i.e. Ba1-xEu2x/3Zr0.05Ti0.95O3 (x=0.00, 0.01, 0.02, 0.03, 0.04, 0.05) samples were synthesized by the conventional solid-state reaction method. The impedance, electric modulus and electrical conductivity behavior in the paraelectric phase has been investigated using the Jonscher's Power law and Jump relaxation model. The conductivity in the samples has been discussed taking into account the oxygen vacancies mechanism. The role of oxygen vacancies in decreasing the electrical conductivity of the doped samples are explained in detail. The deduced activation energies from the conduction and relaxation behavior decrease with increasing the Europium content. The X-ray diffraction (XRD) plot deduced that the Eu3+ ions tend to occupy Ba-site and the crystal structure changes from orthorhombic to tetragonal with Eu doping. The solubility of Eu in BaZr0.05Ti0.95O3 was found maximum up to x <= 0.02 and secondary phases were observed for a higher concentration of Eu. Scanning electron microscopy (SEM) images show that the grain size is reducing as an influence of Eu3+ ions. Also, due to the impact of secondary phase neck between the grains are observed at grain boundaries for the compositions x >= 0.03.