Ceramics-Silikáty 38, (3) 163 - 165 (1994)

The synthesis of barium-titanium mixed oxide, BaTiO₃, from the mixture of barium sulphate, sodium carbonate and titanium oxide in the medium of the molten alkali metal chlorides was realized at the temperatures of 700-900 °C and reaction times of 1-30 min. The conversion degree increases both with temperature and time of heating and in the presence of flux attains at 900 °C almost 100%. The synthetized powders contained BaTiO₃ crystals of two different morphology. The equiaxed BaTiO₃ crystals originate most probably by disintegration of the primarily formed rod-like crystals. According to the X-ray diffraction analysis all prepared powders contain only the tetragonal modification of BaTiO₃. The activation energy of the BaTiO₃ formation was found to be ΔE(BaTiO₃) = 124.6 kJ/mol.