Nonlinear properties of antimony-doped BaTiO_3 ceramics

摘要

Barium titanate nanopowders doped with various concentrations of antimony were synthesized by polymeric precursors method based on modified Pechini process. Obtained powders were pressed and sintered at 1,573 K for 8 h. The temperature dependence of dielectric permittivity pointed on the significant influence of added antimony on dielectric properties of obtained materials. The analysis of impedance spectrum in the temperature range 250-445 K has shown the presence of one semicircle that corresponds to the grain contribution but impedance spectrum at 773 K showed possible overlapping of two semicircles indicating also grain boundary resistivity. The total specific resistivity obtained from impedance analysis showed modest PTCR jump in the heavily doped barium titanate ceramics. The electric field dependence of permittivity of the ceramics was investigated in detail. The experimental data were analyzed using Johnson model.