Structure and electrical properties of (La,Ta)-doped (K0.5Na0.5)0.94Li0.06Nb0.95Ta0.05O3 ceramic

Piezoceramics (K
_0.5
Na
_0.5
)
_0.94-3x
Li
_0.06
La
_x
Nb
_0.95
Ta
_0.05
O
₃
(KNLNT-La
_x
) were synthesized by the conventional solid-state reaction process. The effects of (La,Ta)-doping on the phase structure and electrical properties of (KNLNT-La
_x
) ceramics were investigated. X-ray diffraction analysis showed that the crystal structure of the ceramics with high level of La-doping possessed pseudo-cubic phase and the pseudo-cubic phase structure of the ceramics seriously weakened the dielectric, ferroelectric and piezoelectric properties of the ceramics. In addition, it was found that the ceramics with (La,Ta)-doping displayed a relative lower loss tangent (tand) from room temperature to approximately 350°C.