Fabrication and Ferroelectric Properties of Ba-Doped Strontium Bismuth Titanate Ceramics

In the paper, the microstructure and properties of Sr1-xBaxBi4Ti4O15 (SBBT) ceramics with different Ba contents were investigated. SBBT ceramics were fabricated by means of the method combining Sol-Gel process and ordinary firing. The morphology will change when Ba2+ is doped in SrBi4Ti4O15 (SBTi), which will lead to the change of structure and ferroelectric properties. The microstructure of SBTi and BaBi4Ti4O15 (BBTi) ceramics were characterized by scan electron microscopy (SEM). With the increase of Ba2+ doping contents, the sintering temperature of SBBT ceramics decreases, 1120°C for SBTi and 1060°C for BBTi. BBTi ceramics contain more and larger plate-like grains than that in SBTi, the diameter of the grains in BBTi is about 8~10 µm, the thickness is about 2.5 µm. With the increase of Ba2+ doping contents, remanent polarization (Pr) and coercive electric-field (Ec) increase first and then decrease. At the molar ratio of Sr:Ba=0.5:0.5, SBBT ceramics exhibited the highest Pr and Ec.