Structural and dielectric investigation of rare earth modified SrBi4Ti4O15 ceramics synthesized by high energy ball milling method

Abstract

Lead free ferroelectric ceramics are under active research due to their nontoxic nature. Bismuth layered structure ferroelectric materials have engrossed a lot of consideration in research community due to its versatile applications and tunable electrical properties. In this research work, structural, morphological and electrical properties of rare-earth (Ho3+) modified SrBi4Ti4O15 (SBT) samples are investigated. The ceramic pellets were synthesized by solid state route using high energy ball milling. XRD studies indicated a single phase orthorhombic structure and the morphological investigation revealed formation of grain like features with marginal decrease in average grain size with Ho incorporation. Enhancement in Curie temperature is observed in the modified system. The dielectric constant for pristine SBT and SBHT sample were calculated as 1880 and 1389 at their transition temperature measured at 100 kHz frequency. An abrupt surge in loss at higher temperature can be related to enhancement in conductivity at elevated temperature. The modified sample have shown improved thermal stability making it a suitable candidate for application in high temperature sensors, transducer and actuator application.