Preparation and characterization of barium titanate stannate solid solutions

BaSnxTi1−xO3 (x = 0; 0.05; 0.1; 0.15; 0.2) solid solutions were prepared via conventional solid state reaction and sintered at 1300 °C for 4 h, resulting in dense single phase ceramics with homogeneous microstructures. Tetragonal symmetry for x ≤ 0.1, cubic for x = 0.2 and a superposition of tetragonal and cubic for x = 0.15 compositions were found by X-ray diffraction analysis. The temperature and frequency dependence of the complex dielectric constant and dc tunability were determined. A transformation from normal ferroelectric to relaxor with diffuse phase transition was observed with increasing the Sn concentration. All the investigated compositions show a relative tunability between 0.55 (for x = 0.2) and 0.74 (for x = 0.1), at a field amplitude of E = 20 kV/cm.

Research highlights
► BaSnxTi1−xO3 (x = 0; 0.05; 0.1; 0.15; 0.2) ceramics were prepared by solid state reaction and sintered at 1300∘C for 4h.
► The phase purity, structural parameters and microstructural characteristics were investigated.
► The dielectric properties were studied as function of temperature and frequency and empirical parameters η and δ were calcutate.
► The non-linear dielectric properties (tunability) of the samples were studied at room temperature.
► By increasing the Sn addition, the ɛ(E) dependence tends to reduce its hysteresis behaviour.