Low temperature synthesis of tetragonal BaTiO₃ by using molten salt

Tetragonal BaTiO₃ was prepared by reaction of a layered K ₂Ti₂O₅ and mixed barium salts (BaCl₂ + Ba(NO₃)₂) at above 700°C. The morphology of the particle was cubic shape and the particle size of the products prepared at 700-1000°C was ∼10 μm, and that of the products prepared at higher temperatures (1100-1200°C) was smaller than that of the products prepared at 700-1000°C. From the chemical analysis no potassium atom was detected and the Ba/Ti ratio in the tetragonal BaTiO₃ was 1.00. In the cubic particle of the tetragonal BaTiO₃ surface 90° domain boundaries were observed. Lattice parameters and Curie temperature of the tetragonal BaTiO₃ were a = 3.995(1) and c = 4.036(1) Å and 130°C, respectively.