Lead-free ceramics based on alkaline niobate tantalate antimonate with excellent dielectric and piezoelectric properties

This paper reports lead-free (Na0.52K0.48−x)(Nb0.94−xSb0.06)O3–xLiTaO3 compositions with significantly enhanced piezoelectric properties. The 6% Sb substituted Na0.52K0.48NbO3 was modified by a small amount of LiTaO3, leading to the formation of a morphotropic phase boundary between orthorhombic and tetragonal phases in the range of x = 0.035–0.04 where the materials show a strong compositional dependence of various electrical properties. Excellent properties of d33 = 335 pC/N, kp = 53%, ε 33 T = 2063 , Qm = 41 and Tc = 291 °C were obtained in the composition with x = 0.04, indicating that the ceramics studied are promising as a lead-free piezoelectric candidate.