Dielectric Properties and Diffuse Phase Transition of Sol-Gel Derived 0.94(Bi0.5Na0.5)TiO3-0.06BaTiO3 Ceramics
The 0.94Bi0.5Na0.5TiO3-0.06BaTiO3 (abbreviated to BNT-BT) powder and ceramic was synthesized by sol-gel process. The phase structure and dielectric properties of the ceramics were investigated. The ceramic was sintering at 1000-1100 degree C for 2-4 h in air atmosphere, and the X-ray diffraction (XRD) results revealed that the samples was pure perovskite-type phase. The Curite temperature of BNT-BT ceramics was high up to 348 degree C. The temperature dependence of dielectric permittivity and loss revealed there were two phase transitions, which were from ferroelectric (tetragonal) to anti-ferroelectric (rhombohedral) and anti-ferroelectric to paraelectric (cubic) in BNT-BT ceramics. Diffuse phase transitions were observed in BNT and BNT-BT ceramics and the Curie-Weiss Exponent (CWE) were nearly 2.
X. F. Cheng et al., "Dielectric Properties and Diffuse Phase Transition of Sol-Gel Derived 0.94(Bi0.5Na0.5)TiO3-0.06BaTiO3 Ceramics", Advanced Materials Research, Vols. 311-313, pp. 1481-1484, 2011