Preparation, characterization and dielectric properties of Sr₅RTi₃Ta₇O₃₀ (R=Pr and Eu) ferroelectric ceramics

Abstract

Polycrystalline samples of Sr₅PrTi₃Ta₇O₃₀ (SPTT) and Sr₅EuTi₃Ta₇O₃₀ (SETT) compounds were prepared by high-temperature solid-state reaction method and their formation, structure and dielectric properties were studied. They are found to be ferroelectric phase of filled tetragonal tungsten bronze (TB) structure at room temperature and undergoes diffuse type of ferroelectric-paraelectric phase transition around 34 °C and 31 °C, respectively. At 1 MHz SPTT exhibits high dielectric constants of 177 and low dielectric losses of 3.5×10⁻⁴ and SETT has high dielectric constants of 125 and low dielectric losses of 2.4×10⁻³.

Keywords

dielectrics / ceramic / ferroelectric / tungsten-bronze

References

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