Study of Impedance Spectroscopy of Ferroelectric (Pb Sr)TiO 3 Glass Ceramic System with Addition of La 2 O 3

Abstract

Various composition of glasses were prepared by melt-quenched method in the glass ceramic system 64[(Pb x Sr 1- x )⋅OTiO 2 ]-25[(2SiO 2 ⋅B 2 O 3 )]-7[BaO]-3[K 2 O] doped with 1 mole % La 2 O 3 ( 0.0 ≤ x ≤ 0.4 ). Solid solution of perovskite lead strontium titanate (PST) phase was crystallized in borosilicate glassy matrix with controlled heat treatment schedule. X-ray diffraction analysis of these glass ceramic samples revealed that major crystalline phase of the entire glass ceramic samples bears cubic structure similar to SrTiO 3 ceramic. Impedance spectroscopy studies were done in the frequency range 0.01 Hz to 3.0 MHz and in the temperature range 50 to 275°C. Impedance and complex modulus spectroscopic techniques were used to find out the various contributions to the polarization process. Resistive and capacitive contributions of the processes relaxing in the highest frequency range were found to have low values in comparison to the resistive and capacitive contributions for the processes relaxing in lower and intermediate frequencies ranges.