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

Abstract This paper reports lead-free (Na 0.52 K 0.48− x )(Nb 0.94− x Sb 0.06 )O 3 – x LiTaO 3 compositions with significantly enhanced piezoelectric properties. The 6% Sb substituted Na 0.52 K 0.48 NbO 3 was modified by a small amount of LiTaO 3 , 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 d 33 = 335 pC/N, k p = 53%, e 33 T = 2063 , Q m = 41 and T c = 291 °C were obtained in the composition with x = 0.04, indicating that the ceramics studied are promising as a lead-free piezoelectric candidate.