Observation of high dielectric properties of Mg-substituted BST ceramic synthesized by conventional solid-state route

Abstract

Barium Strontium Titanate exhibits ferroelectric or paraelectric behaviour that depends upon the composition and other factors, making it suitable for a number of applications. We have adopted conventional solid state reaction route to synthesize magnesium substituted barium strontium titanate with low concentration of Mg (Mg= 0.005, 0.010 and 0.015). X-ray diffraction has con rmed the perovskite cubic single phase. The dielectric studies were carried out as a function of temperature at different xed frequencies (1kHz, 10kHz, 50kHz and 100kHz) and as a function of frequency at room temperature. The Curie's temperature of pure BST was 96°C and for Mg substituted BST samples it dropped from 85°C to 63°C. The dielectric permittivity rstly suppressed and then maximum value observed for Mg content 0.015 and dielectric loss is also less than one. The remanance (P r ) and coercivity (E c ) are obtained and analysed for ceramics samples. Improvement in dielectric properties due to substitution of Magnesium is observed.