Enhanced dielectric properties of BaTiO3 based on ultrafine powders by two-step calcination

As high-performance dielectric material , small sizes of barium titanate (BaTiO 3 ) are desirable for the application of multilayer ceramic capacitors . Herein, we synthesized ultrafine BaTiO 3 powders with mean particle size of ( d av. ) 156 nm, tetragonality ( c/a ) of 1.0092 and specific surface area ( S BET ) of 6.09 m 2 /g by two-step sintering process. Kinetic analysis of solid-state reaction reveals that the phase-boundary-controlled mechanism dominated the reaction process in two-step sintering process compared with one-step sintering process dominated by the first-order mechanism. It is also shown that enhanced nucleation in two-step calcination is beneficial for improving the tetragonality. In particular, the dielectric constant and dielectric loss of BaTiO 3 ceramics at the Curie temperature are found to be about 12800 and 0.003. This work demonstrates a strategy to trigger a method which can effectively improve the dielectric properties of BaTiO 3 ceramic.