A high temperature piezoelectric ceramic: (1-x)(Bi0.9La0.1)FeO3-xPbTiO3 crystalline solutions

(1-x)(Bi
_0.9
La
_0.1
)FeO
_3-x
PbTiO
₃
(BLF-PT) crystalline solutions for x = 0.35, 0.37, 0.4, 0.43 and 0.45 have been prepared by the solid-state reaction method. The X-ray diffraction analysis shows that BLF-PT has a single perovskite phase with mixed tetragonal and rhombohedral phases between x = 0.4 and 0.43. The Curie temperature of BLF-PT for x = 0.4 attains 460degC, which is about 80degC higher than that of hard Pb(Zr,Ti)O
₃
ceramics. The remnant polarization and piezoelectric constant of BLF-PT for x = 0.4 reach 38 muC/cm
²
and 112 pC/N, respectively. The planar coupling factor k
_p
of BLF-PT for x = 0.4 remains stable at temperature increases of up to 360degC. The impedance spectroscopy study reveals that the high temperature conduction of BLF-PT may be attributed to the motion of oxygen vacancies within the material. Our results indicate that BLF-PT is a promising candidate for high temperature applications.