Uniaxial Pressure Effect on Dielectric Properties of 0.7Na_{0. 5}Bi_0.5TiO₃‐0.3SrTiO₃ Ceramics

Abstract

The 0.7Na_0.5Bi_0.5TiO₃-0.3SrTiO₃ ceramics were prepared by a solid-state mixed-oxide technique at 1180°C. X-ray diffraction and Raman spectroscopy studies revealed that the obtained samples possess perovskite structure. The behaviour of the electric permittivity (ɛ) and polarization of these ceramics as a function of uniaxial pressure (0 – 1000 bar) were investigated. Applying pressure shifts and decrease of maximum value of ɛ, a diffuseness of the permittivity characteristics, decrease of the thermal hysteresis and change of the polarization. We discuss our results based on elastic changes in inter-ionic distances in the crystal structure and nanoregions switching processes by pressure. The 0.7Na_0.5Bi_0.5TiO_3-0.3SrTiO₃ ceramics are expected to be a new promising candidate for lead-free electronic material.

Keywords:

• 0.7Na_0.5Bi_0.5TiO_3-0.3SrTiO₃
• dielectric properties
• uniaxial pressure