Preparation, characterization and dielectric property of Sr₅LaTi₃Nb₇O₃₀ ceramic

Abstract

Sr₅LaTi₃Nb₁O₃₀ ceramic was prepared by the conventional high temperature solid-state reaction route. The sintered samples were characterized by X-ray diffraction, scanning electron microscopy (SEM), differential thermal calorimetry (DSC) and dielectric measurements. The results show Sr₅LaTi₃Nb₇O₃₀ belongs to paraelectric phase of filled tetragonal TB structure at room temperature, and undergoes a diffuse phase transition in the temperature range of−54-34°C. And Sr₅LaTi₃Nb₇O₃₀ ceramic shows a high dielectric constant of 479 with a low dielectric loss of 0.005 at 1 MHz. In comparison with Ba-based ceramics with TB structure, the temperature coefficients of the dielectric constant (τ_ε) is significantly reduced.

Keywords

niobate / dielectric properties / phase transition / tungsten bronze

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