Synthesis of Tetragonal BaTiO₃by Microwave Heating and Conventional Heating

Hydrothermal synthesis of barium titanate was done by both microwave heating and conventional heating. The synthesis process was evaluated by examining samples at different processing times by X-ray diffraction. For samples produced by both heating methods, the metastable cubic phase crystallized first and gradually transformed to a tetragonal phase. Microwave synthesis showed advantages of shortened crystallization time, increased c / a ratio, and upon sintering led to a larger degree of increased c / a ratio. Elemental analysis showed a smaller Ti/Ba ratio and larger relative amount of Cl - ion in the microwave-treated sample than those in a conventionally treated sample. Sintering at 850 °C for both samples resulted in the samples exhibiting a clear transition temperature of around 125 °C as measured by DSC.