Synthesis, crystallisation and microstructural study of perovskite (Ba,Sr)TiO₃ borosilicate glass ceramic doped with La₂O₃

Abstract

Various glass samples, of glass system [(Ba_1−xSr_x)TiO₃]–[2SiO₂–B₂O₃]–K₂O with addition of La₂O₃, were prepared by melt quenched method. Differential thermal analysis of glass samples was carried out in the temperature range of 100–1200°C in order to study the kinetics of crystallisation behaviour. Glass samples were subjected to appropriate heat treatment schedules for their suitable crystallisation from glass to glass ceramics. X-ray diffraction analysis of glass ceramic samples indicated the presence of major crystalline phase of BaTiO₃ along with some secondary phases of Ba₂TiSi₂O₈ and Ba₂Ti₂B₂O₉. Scanning electron microscopy measurements were also performed to see the morphology of crystallites of the major/secondary phase formation in the glass ceramic samples. We found that La₂O₃ played an important role to increase nucleation and growth of the crystallites in the glassy matrix.

Keywords:

• BST glass ceramics
• DTA
• Crystallisation
• XRD
• SEM

Acknowledgements

The authors are gratefully acknowledged to the University Grant Commission, New Delhi, India, for financial support under Major Research Project F No. 37-439/2009 (SR). The authors also thankful to Professor R. P. Singh, IISER, Pune, for his encouragement and invitation in ISME-2011.