Structure and electrical properties of K0.5Na0.5Nb0.94−xSb0.06SnxO3 lead-free piezoelectric ceramics

A new lead-free piezoelectric ceramics K0.5Na0.5Nb0.94−xSb0.06SnxO3 with high densification and excellent properties have been prepared by conventional solid state sintering technique at 1090 °C for 2 h in air. The effect of tin content on the structure and electrical properties of the KNNSS-x ceramics have been systematically studied. The results show that the ceramics exhibit a pure perovskite structure with orthorhombic phase at room temperature, and the moderate tin adding can effectively improve the physical properties and the sintering of the ceramics. It was exhibited that the KNNSS-0.03 ceramic shows a optimum properties (d33 = 288 pC/N, kp = 48%, εr = 1286, tan δ = 2.9%, Pr = 30.1 μC/cm2, EC = 1.01 kV/mm, Tc = 419 °C), which suggesting the ceramics is a kind of practical lead-free ceramics.