Synthesis of barium titanate by electrostatic levitation

A spheroid BaTiO3 with a diameter ca. 2 mm was synthesized using a pressurized electrostatic levitation furnace. Phase selection was controlled by varying the superheating and undercooling. A polycrystalline perovskite BaTiO3 was crystallized from a homogeneous melt superheated by 150 K and then undercooled by 750 K (∼0.4 Tm), whereas a single crystal of hexagonal BaTiO3 was grown from a melt superheated by 50 K and then undercooled by 100 K. The polycrystalline perovskite BaTiO3 solidified from undercooled melt showed a high dielectric constant of 4000 at room temperature.