Piezoelectric Properties of (1 – X)BiScO3 – XPbTiO3 System for Actuator Applications

ABSTRACT In this research, the crystalline and piezoelectric properties of (1 – X )BiScO 3 – X PbTiO 3 ( X = 0.60, 0.62, 0.64, 0.66 and 0.68) ceramics were investigated to determine the optimized composition for energy harvester and sensor applications. BS-PT ceramics have strong merits in terms of their high Curie temperature and piezoelectric charge coefficient. Devices of the (1 – X )BS- X PT ceramics were fabricated by a conventional mixed-oxide sintering process with nano-powders. By employing the X-ray diffraction patterns, the morphotropic phase boundary (MPB) region of the monoclinic and tetragonal phases was identified at X = 0.64. Near the MPB region, the piezoelectric and dielectric properties of BS-PT ceramics were improved compared with those of other composition. By optimizing the compositions of the BS-PT ceramics, the maximum values of the dielectric constant ( ε r ), piezoelectric charge coefficient (d 33 ), electromechanical coupling factor (k p ) and remanent polarization (P r ) were obtained, with values of 1387, 417 pC/N, 51.4% and 44.8 µ C/cm 2 , respectively. Moreover, a high Curie temperature of 399.2 °C and inverse piezoelectric charge coefficient of 574 pm/V were observed for the 0.36BS–0.64PT composition, which can be a huge merit for actuator applications. These high piezoelectric charge coefficients and inverse piezoelectric charge coefficients can be the strong merits for energy harvester and actuator applications.