Investigations on the synthesis of Bi3NbTiO9 ceramics

The perovskite-layered ceramics of Bi3NbTiO9 (BNT), also known as Aurivillius phase, was obtained. The process of preparation was investigated by X-ray diffraction method. The synthesis of BNT was carried out according to the solid-state reaction from the conventional mixture of oxides (Bi2O3, TiO2, Nb2O5) within the temperature range T-S = 400-1200 degrees C. The influence of addition of NaCl on the process of synthesis was also investigated. It was found that above T-S = 900 degrees C the ratio of the Bi3NbTiO9 phase was almost 90% and the admixture of NaCl decreased the synthesis temperature. Dependence of the amount of the BNT phase in the bulk material vel sus the temperature of synthesis is given. Evolution of the structural parameters of BNT and NaCl - modified BNT at different synthesis temperatures was shown as well as recording of Raman scattering spectra. (C) 1999 Elsevier Science Limited. All rights reserved.