TY - JOUR
T1 - Dependency of direct and inverse transverse piezoelectric properties on composition in self-polarized epitaxial (KxNa1-x)NbO3films grown via a hydrothermal method
AU - Tateyama, Akinori
AU - Ito, Yoshiharu
AU - Shimizu, Takao
AU - Orino, Yuichiro
AU - Kurosawa, Minoru
AU - Yoshimura, Takeshi
AU - Funakubo, Hiroshi
N1 - Publisher Copyright:
© 2020 The Japan Society of Applied Physics.
PY - 2020/11/1
Y1 - 2020/11/1
N2 - (KxNa1-x)NbO3 films that were approximately 3 μm in thickness and with various x values were systematically deposited at 240 C on (100)cSrRuO3//(100)SrTiO3 substrates using a hydrothermal method. Direct and inverse transverse piezoelectric coefficients, e 31,f, near 0 kV cm-1 were approximately -5.0 C m-2 for the as-deposited films with a wide range of x values without any poling treatment. A large difference in e 31,f value was not observed before or after poling treatment upon applying a positive electric field, suggesting that the as-deposited (KxNa1-x)NbO3 films with x = 0.36-0.88 were almost fully in a self-polarized state. (KxNa1-x)NbO3 films with x = 0.36-0.88 without any poling treatment showed a figure of merit for an energy harvester (FOM = e 31,f2/ϵ r) above 0.13, as calculated directly from e 31,f. These FOM values are relatively high compared with the reported ones for other lead-free films that have a perovskite structure.
AB - (KxNa1-x)NbO3 films that were approximately 3 μm in thickness and with various x values were systematically deposited at 240 C on (100)cSrRuO3//(100)SrTiO3 substrates using a hydrothermal method. Direct and inverse transverse piezoelectric coefficients, e 31,f, near 0 kV cm-1 were approximately -5.0 C m-2 for the as-deposited films with a wide range of x values without any poling treatment. A large difference in e 31,f value was not observed before or after poling treatment upon applying a positive electric field, suggesting that the as-deposited (KxNa1-x)NbO3 films with x = 0.36-0.88 were almost fully in a self-polarized state. (KxNa1-x)NbO3 films with x = 0.36-0.88 without any poling treatment showed a figure of merit for an energy harvester (FOM = e 31,f2/ϵ r) above 0.13, as calculated directly from e 31,f. These FOM values are relatively high compared with the reported ones for other lead-free films that have a perovskite structure.
UR - http://www.scopus.com/inward/record.url?scp=85091103976&partnerID=8YFLogxK
U2 - 10.35848/1347-4065/aba9b3
DO - 10.35848/1347-4065/aba9b3
M3 - Article
AN - SCOPUS:85091103976
SN - 0021-4922
VL - 59
JO - Japanese Journal of Applied Physics
JF - Japanese Journal of Applied Physics
IS - SP
M1 - SPPC03
ER -