Influence of grain size effect and Ba/Ti ratios on dielectric, ferroelectric, and piezoelectric properties of BaTiO3 ceramics. (4th September 2019)

• Record Type: Journal Article
• Authors: Sapkota, Piyush; Ueno, Shintaro; Fujii, Ichiro; Khanal, Gopal Prasad; Kim, Sangwook; Wada, Satoshi
• Is Part Of: Japanese journal of applied physics. Volume 58:Number SL(2019)
• Publication Date: 2019-09-04
• Subjects: Physics -- Periodicals; 621.05
• DOI: 10.7567/1347-4065/ab3b1c
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: The grain size effect on the dielectric, ferroelectric, and piezoelectric properties of BaTiO3 (BT) ceramics with different Ba/Ti ratios, prepared by solid-state reaction and conventional sintering, was investigated, and the corresponding electrical properties of these ceramics with similar grain size were compared. The BT ceramics with Ba/Ti ratios of 0.997, 1.000, and 1.003 and grain sizes of approximately 1 μ m exhibited dielectric constants of 4265, 4275, and 4835 and converse piezoelectric coefficients, d 33 *, of 703, 645, and 466 pm V −1, respectively. The remanent polarization, P r, was relatively higher for Ba-excess BT ceramics. These results indicated that, in Ti-excess BT ceramics, domain walls were strongly pinned due to oxygen vacancies under small electric fields and they were de-pinned at high electric fields, contributing to the higher d 33 *, while the orientation of domains in high electric fields did not retain upon electric field unloading, resulting in lower P r .