Crystallization and dielectric properties of Fe2O3 doped barium strontium titanate borosilicate glass

Abstract

An attempt has been made to prepare barium strontium titanate borosilicate glasses in the system, 64[(Ba_1−xSr_x)·TiO₃]–30[2SiO₂·B₂O₃]–5[K₂O]–1[Fe₂O₃] (0.4 ≤ x ≤ 1.0), using the conventional melt-quench method. The prepared glasses were characterized by differential thermal analysis, X-ray diffraction, scanning electron microscopy and impedance spectroscopy techniques. On the basis of the DTA results, the glasses were crystallized via regulated heat treatment process. The activation energy for crystallization was 818 ± 1.6 kJ mol⁻¹. A high dielectric constant of about 107 070 was obtained for the 6 hour heat treated glass ceramic sample. Fe₂O₃ plays an important role in enhancing crystallization, dielectric constant and retardation of dielectric loss in the samples.