EFFECT OF SYNTHESIS METHOD ON BaTiO3 PROPERTIES

Abstract

Barium titanate (BaTiO3) has been of practical interest for more than 60 years because of its attractive properties. BaTiO3 can be prepared using different methods. It was detected a significant influence of used method on structure and properties of barium titanate materials. In this paper powder of BaTiO3 was prepared by two methods. The first one was synthesis from polymeric precursors through Pechini process (soft chemistry-PPM) which was carried out as a three–stage process from oganometallic complex [1]. The second one was a mechanochemical synthesis from powder mixture of BaO and TiO2 [2]. In both cases BaTiO3 was sintered for 2h at 1300oC without pre-calcination step. The formations of phase and crystal structure of BaTiO3 prepared by both methods were carried out by XRD analysis. The morphology and microstructure of obtained powders and sintered samples were examined by SEM method. The XRD results of powders obtained by both methods indicate the formation of cubic phase of BaTiO3 and tetragonal phase in sintered samples. BaTiO3 powder prepared by PPM was well crystallized but significant amount of amorphous phase was detected for other method. SEM micrographs indicate that the morphology of the powders consists of particles and its agglomerates and their dimensions depend of the synthesis method. The powder prepared mechanochemically possesses higher number of agglomerates, particles are bigger and with irregular shape. Average particle size is about 100 nm and 250 nm for Pechini and mechanochemical process, respectively. Two types of domain configuration were observed in samples sintered at 1300oC for 2h and prepared from powders obtained by PPM.