(Ba1−xBi0.33xSr0.67x)(Ti1−xBi0.67xV0.33x)O3 and (Ba1−xBi0.5xSr0.5x)(Ti1−xBi0.5xTi0.5x)O3 solid solutions: phase evolution, microstructure, dielectric properties and impedance analysis

Perovskite solid solution ceramics of (Ba 1− x Bi 0.33 x Sr 0.67 x )(Ti 1− x Bi 0.67 x V 0.33 x )O 3 and (Ba 1− x Bi 0.5 x Sr 0.5 x )(Ti 1− x Bi 0.5 x Ti 0.5 x )O 3 (BBSTBV, BBSTBT, 0.02 ≤ x ≤ 0.2) were prepared by the traditional solid state reaction technique. The phase evolution, microstructure and dielectric properties of BBSTBV and BBSTBT ceramics were researched. X-Ray diffraction results illustrated that both BBSTBV and BBSTBT could form a homogenous solid solution which has a similar structure with BaTiO 3 . The optimized properties of (Ba 0.8 Bi 0.1 Sr 0.1 )(Ti 0.8 Bi 0.1 Ti 0.1 )O 3 ceramics with stable ε r (~ 1769–2293), small Δ ε / ε 25 °C values (± 15%) over a broad temperature range from − 58 to 151 °C and low tan δ ≤ 0.03 from − 11 to 131 °C were obtained. In the high-temperature region, the relaxation and conduction process are attributed to the thermal activation and the oxygen vacancies may be the ionic charge carriers in perovskite ferroelectrics.