Phase relationship in a BaO-Bi2O3-TiO2 system and electrical properties of BaTiO3 with addition of Bi4Ti3O12

A phase relationship of the BaO-Bi2O3-TiO2 system at 1273 K was studied using a solid state reaction. A new compound of BaBi6Ti20O50 was found in this ternary system. In the BaTiO3-Bi4Ti3O12 pseudo-binary system, the solid solution of Bi4Ti3O12 into BaTiO3 was observed Lip to 4 mol% Bi4Ti3O12. The lattice parameters of tetragonal BaTiO3 varied depending on Bi4Ti3O12 content in the solid solution range. The structure of BaTiO3 became cubic with the addition of more than 4 mol% Bi4Ti3O12. The temperature dependence of permittivity obeyed the Curie-Weiss-like behavior in the solid solution range. The highest permittivity of BaTiO3 decreased and the peak of permittivity became broader with increasing Bi4Ti3O12 content.