Crystal structure, ferroelectric and piezoelectric properties of epitaxial (1−x)(Bi0.5Na0.5)TiO3–x(Bi0.5K0.5)TiO3 films grown by hydrothermal method. (27th August 2020)

• Record Type: Journal Article
• Authors: Huang, Yu; Ito, Yoshiharu; Tateyama, Akinori; Kurosawa, Minoru; Funakubo, Hiroshi
• Is Part Of: Japanese journal of applied physics. Volume 59:Number SP(2020)
• Publication Date: 2020-08-27
• Subjects: Hydrothermal synthesis -- (1−x)BNT-x -- BKT epitaxial films -- Composition dependencies -- Ferroelectric and piezoelectric properties; Physics -- Periodicals; 621.05
• DOI: 10.35848/1347-4065/abad45
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: The composition dependencies of crystal structure, and electrical and electromechanical properties were systematically investigated for epitaxial films of (1− x )(Bi0.5 Na0.5 )TiO3 – x (Bi0.5 K0.5 )TiO3 [(1− x )BNT– x BKT ( x = 0 –1)] deposited on (100) c SrRuO3 //(100)SrTiO3 substrates by a hydrothermal method. An In-plane crystal lattice was clamped by that of underlying SrRuO3 irrespective of the x value. The dielectric constant decreased monotonously with increasing x . The polarization–electric field hysteresis loops were imprinted due to the preferential polarization in the films. In addition, the increase of tetragonality with increasing x value contributes to the increase of saturation and remnant polarization ( P sat. and P r, respectively), coercive field ( E c ) as well as P r / P sat. values. The effective piezoelectric coefficient (near E = 0 kV cm −1 ) improved considerably with increasing x, reaching a maximum of 62 pm V −1 in the BKT film. A comprehensive and systematic study has been performed on (1− x )BNT– x BKT epitaxial films in this work, which lays the foundation for further research of this system in the future.