Lowering Synthesis Temperature of BaTiO₃-Bi(Zn_0.5Zr_0.5)O₃ Ceramics by Salt Flux Assistance and Dielectric Properties Investigations

Abstract

Phase formations and dielectric properties of lead free barium titanate bismuth zinc zirconate, BaTiO₃-Bi(Zn_0.5Zr_0.5)O₃ (BT-BZZ), were comparatively investigated between two different synthesis routes, solid state reaction and salt flux assistance methods. The perovskite (1-x)BT-(x)BZZ ceramics, where x = 0.02, 0.05 and 0.10, were synthesized by using reagent grade oxides and the NaCl salt was used as a surface active agent to lower the calcination temperature. Phase formations were examined by X-ray diffraction technique (XRD). It was found that the solid solutions of (1-x)BT-(x)BZZ can be obtained with lower temperature at least 200 °C via salt flux assistance method. The NaCl salt addition could result in single phase of perovskite structure at every compositions with the calcination temperature as low as 800 °C. Dielectric measurements revealed that the Curie temperature (T_c) shifted to lower temperature with increase of BZZ concentration. Moreover, the dielectric behavior transformed to diffuse phase transition when x = 0.1. The samples prepared via salt flux assistance method exhibited smaller grain size which were revealed by scanning electron microscope. In addition, P-E hysteresis measurements illustrated the higher high E-field dielectric constant with the narrower P-E loop when the salt flux was applied.

KEYWORDS:

• Dielectric
• barium titanate
• salt
• zirconate

Acknowledgments

In addition, Prof. Dr. Rattikorn Yimnirun is sincerely acknowledged for all guidance.

Additional information

Funding

This work was financially supported by the Development and Promotion of Science and Technology Talents Project (DPST), the Institute for Promotion of Teaching Science and Technology (IPST) under the Research Fund for DPST Graduate with First Placement (Fiscal Year 2015) and Silpakorn University Research, Innovation and Creative Fund (Fiscal Year 2016).