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 confirmed the perovskite cubic single phase. The dielectric studies were carried out as a function of temperature at different fixed 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 firstly suppressed and then maximum value observed for Mg content 0.015 and dielectric loss is also less than one. The remanance (Pr) and coercivity (Ec) are obtained and analysed for ceramics samples. Improvement in dielectric properties due to substitution of Magnesium is observed.