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

Barium strontium titanate exhibits ferroelectric or paraelectric behavior that depends upon the composition and other factors, making it suitable for several applications. We have adopted the conventional solid-state reaction route to synthesize magnesium-substituted barium strontium titanate with magnesium concentration (Mg = 0, 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 (1 kHz, 10 kHz, 50 kHz, and 100 kHz) and as a function of frequency at room temperature. Curie’s temperature of pure BST was 96 °C, and for Mg-substituted BST samples, it dropped from 85 to 63 °C. The dielectric permittivity is firstly suppressed and then the maximum value observed for Mg content 0.015 and dielectric loss is also less than one. The remanence (Pr) and coercivity (Ec) are obtained and analyzed for ceramics samples. Improvement in dielectric properties due to substitution of magnesium is observed.