Studies of structural and electrical properties of (Pb0.9Bi0.05Dy0.05)(Fe0.1Ti0.9)O3 ceramic

Abstract

In this communication, detailed studies of structural, dielectric, and electrical characteristics of dysprosium (Dy)-modified bismuth ferrite–lead titanate (BiFeO3–PbTiO3) solid solution, [i.e., (Pb0.9Bi0.05Dy0.05)(Fe0.1Ti0.9)O3)], prepared by a standard high-temperature solid-state reaction route, have been reported. From the preliminary X-ray structural analysis with Rietveld refinement method, the structure of the material is found to be tetragonal. Detailed analysis of surface morphology, X-ray energy-dispersive spectra and elemental mapping has shown uniform distributions of grains of varying size and elemental composition of the compound. The frequency dependence of the dielectric constant has been explained by the Maxwell–Wagner model. As both the components of the solid solution (BiFeO3 and PbTiO3) have high-temperature ferroelectric transition, no dielectric anomaly has been observed in the said experimental range of our temperature dependence of dielectric studies. The detailed analysis of Nyquist plots, using impedance data collected in a wide range of frequency and temperature shows the contributions of both grains and grain boundaries in the resistive and capacitive characteristics of the prepared material. Both negative and positive temperature coefficients of resistance behaviour are observed in the material. The frequency and temperature dependence of ac conductivity obeys Jonscher’s power law and Arrhenius equation. The occurrence of electric field dependence (P–E) hysteresis loop at room temperature shows the ferroelectric property of the material.