Impedance spectroscopy and thermally simulated depolarization current study of barium strontium titanate glass ceramics: Effect of thermal annealing atmosphere on dielectric property

摘要

The effect of thermal annealing atmosphere on dielectric properties of barium strontium titanate glass ceramics was investigated by impedance analysis and thermally stimulated depolarization current measurement. As a result of impedance analysis, the resistances of both air-annealed and O-2-annealed glass ceramic samples were found to be two orders of magnitude higher than that of the as-sintered samples. This annealing atmosphere induced change in electrical properties can be ascribed to the variation in oxygen vacancy concentration. From the thermally stimulated depolarization current measurement, the annealing atmosphere dependence of current density was found for the annealed samples. It was shown that the reduction in oxygen vacancy concentration lowers the ac conductivity and defect dipole concentration.