Phase Formation and Dielectric Properties of Ba_0.9Sr_0.1[Ti_1-x(Fe_0.5Nb_0.5)_x]O₃ Ceramics

Abstract

In this work, the complex perovskite Ba_0.9Sr_0.1[Ti_1-x (Fe_0.5Nb_0.5)_x]O₃ (BST-FN) ceramic system with x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5 were synthesized via a solid state reaction method. The ceramics were subsequently examined at room temperature by X-ray diffraction using Cu K_α radiation to identify the phase composition of each sample. The structures of the samples were found to be tetragonal and the tetragonality of which decreased with increasing the FN content. The relative permittivity and loss tangent were found to increase with temperature. The highest ϵ_r was 2941 with the tan δ of 0.713 for x = 0.2 at room temperature and at 1 kHz.

Keywords:

• Lead-free piezoelectric
• phase transiton
• barium strontium titanate
• barium iron niobate

Acknowledgments

The authors would like to thank the Thailand Research Fund, the National Research University Project under Thailand's office of the Higher Education Commission, National Metal and Materials Technology Center (MTEC) and Faculty of Science, Chiang Mai University for financial support.