Influence of Sb2O3 doping on the properties of KBT-NBT-BT lead-free piezoelectric ceramics

Abstract

0.144(K0.5Bi0.5)TiO3-0.85(Na0.5Bi0.5)TiO3-0.006BaTiO3 (KBT-NBT-BT) lead-free piezoelectric ceramics were prepared using a conventional solid state method. The influence of Sb2O3 doping on the crystal phase, surface microstructure and properties of the KBT-NBT-BT lead-free piezoelectric ceramics were investigated using X-ray diffraction (XRD), scanning electron microscope (SEM) and other analytical methods. The results show that all compositions are of pure perovskite structure solid states. Sb2O3 doping does not influence the microstructure of KBT-NBT-BT lead-free piezoelectric ceramics obviously in the Sb2O3 doping range of 0.1-0.5 wt.%. Sb2O3 functions as a donor when doped small amount, while functions as a acceptor when doped large amount. The piezoelectric strain constant (d33) increases first and then decreases; the dielectric constant (e(superscript T subscript 33)/e0) and the dielectric loss (tan δ) decrease continuously when the amount of Sb2O3 dopant increases. When the doping amount of Sb2O3 is 0.1 wt.%, the KBT-NBT-BT piezoelectric ceramics with good comprehensive properties are obtained, whose d33, e(superscript T subscript 33)/e0 and tan δ are 147 pC/N, 1510 and 4.2%, respectively.