Microstructure and electrical properties of tantalum doped (Ba0.85Ca0.15)(Zr0.10Ti0.90)O3 ceramics

• Published in: Journal of materials science. Materials in electronics Vol. 26; no. 2; pp. 909 - 915
• Main Authors: Zhang, Donghui, Zhang, Yueli, Yang, Shenghong
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.02.2015; Springer Nature B.V
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Materials Science; Optical and Electronic Materials; Ferroelectric Hysteresis Loop; Dielectric Maximum; Piezoelectric Property; BaTiO3; Diffuse Phase Transition
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-014-2481-2

(Ba 0.85 Ca 0.15 )(Zr 0.10 Ti 0.90 ) 1− x Ta x O 3 ceramics (BCZTT, 0 ≤  x  ≤ 3.0 mol%) were prepared via a conventional solid-state reaction method, and the effect of Ta substitution on the microstructure and electrical properties of the BCZTT ceramics was investigated. A pure perovskite structure was obtained in all of these samples. The microstructure of the BCZT ceramics is strongly affected by Ta doping. Low-concentration Ta addition ( x  = 0.1 mol%) promotes the grain growth of the BCZT ceramics. However, high-concentration Ta addition ( x  > 0.5 mol%) effectively hinders the grain growth. The dielectric, ferroelectric and piezoelectric properties of the BCZT ceramics are improved by addition of a small amount of Ta. For the ceramics with x  = 0.3 mol%, electrical performance reaches optimum: ε max  = 7,770, T max (the temperature of the dielectric maximum) = 101.8 °C, P max  = 17.9 μC/cm 2 , P r  = 9.1 μC/cm 2 , E c  = 0.54 kV/mm and d 33  = 303 pC/N. The T max of the BCZTT decreases with the increasing Ta concentration. The relaxor properties of undoped and Ta-doped BCZT ceramics were depicted, and the diffusivity increases with the increasing Ta contents.