Investigations on nanocrystalline BST-LSMO magnetodielectric composites

M M Sutar,A N Tarale,P B Joshi,S R Jigajeni,S B Kulkarni

doi:10.1007/s13204-012-0119-3

Abstract

The paper reports the synthesis of Ba1−xSrxTiO3 (BST) for x = 0.20, 0.25, and 0.30 via hydroxide co-precipitation route to result into the BST nanoparticles of size nearly 50 nm. The La0.67Sr0.33MnO3 (LSMO) is also synthesized using co-precipitation route to achieve nanocrystaline particles. Further, the magnetodielectric (MD) composites of BST0.20, BST0.25, and BST0.30 are formed by addition of the LSMO at y = 0.1 and 0.2. The parent BST compositions are analysed for its dielectric properties. The composite LSMO-BST (LBST) is investigated for the variation of dielectric constant and impedance spectra as a function of applied magnetic field for the frequency between 500 Hz to 1 MHz. The observations on MD effect show that the dielectric constant possesses contributions due to magnetic field dependant interfacial polarization and variations due to the induced stress.

Highlights

Ba1-xSrxTiO3 (BST) is a well-known ferroelectric material where the transition temperature (Tc) could be reduced nearly from 120 °C down to -231 °C by varying x between 0 and 1 (McCormick et al 2001)
It is observed that the hydroxide co-precipitation route could be successfully used to form nanoparticles of both the BST and LSMO compositions
The initial particle size of the BST is observed to be in the range of 49–65 nm and for LSMO it is observed to be nearly 67 nm

Summary

Introduction

Ba1-xSrxTiO3 (BST) is a well-known ferroelectric material where the transition temperature (Tc) could be reduced nearly from 120 °C down to -231 °C by varying x between 0 and 1 (McCormick et al 2001). The composite LSMO-BST (LBST) is investigated for the variation of dielectric constant and impedance spectra as a function of applied magnetic field for the frequency between 500 Hz to 1 MHz. The observations on MD effect show that the dielectric constant possesses contributions due to magnetic field dependant interfacial polarization and variations due to the induced stress.

Results

Conclusion