Piezoelectric properties and microstructures of ZnO-doped Bi0.5Na0.5TiO3 ceramics

This article studies the microstructure and piezoelectric properties of a ceramic lead-free NBT under different amount of ZnO doping. X-ray diffraction shows that Zn2+ diffuses into the lattice of (Bi0.5Na0.5)TiO3 to form a solid solution with a pure perovskite structure. By modifying the zinc oxide content, the sintering behavior of (Bi0.5Na0.5)TiO3 ceramics was significantly improved and the grain size was increased. The piezoelectric coefficient d33 for the 1.0 wt.% ZnO-doped (Bi0.5Na0.5)TiO3 ceramics sintered at 1050 °C was found to be 95 pC/N, and the electromechanical coupling factor kp = 0.13. However, the piezoelectric coefficient d33 for the 0.5 wt.% ZnO-doped (Bi0.5Na0.5)TiO3 ceramics sintered at 1140 °C was found to be 110 pC/N, and the electromechanical coupling factor kp = 0.17.