Influence of PNN on the structure and electronic properties of BSPT ceramics

The influence of Pb(Ni1/3Nb2/3)O3 (PNN) on the structure and electronic properties of 0.36BiScO3–0.64PbTiO3 (BSPT) piezoelectric ceramics which were synthesized by the conventional solid-state synthesis have been systematically investigated. It was found that the ceramics with lower PNN content exhibited normal ferroelectric behavior. However, the ceramics showed a diffused phase transition characteristic as PNN content increased. The BSPT–xPNN ceramics when x = 1% showed enhanced piezoelectric properties with piezoelectric constant d33 = 531 pC/N, planar electromechanical coupling factors kp = 0.58, remnant polarization Pr = 34.6 µC/cm2, and coercive field Ec = 12.0 kV/cm with a high Curie temperature TC = 417 °C. The enhanced piezoelectric/ferroelectric properties and higher Curie temperature of the BSPT–xPNN ceramics are mainly ascribed to the lower level of the tetragonality and lower tolerance factor. As result, this material system is one of the promising candidates for high temperature piezoelectric applications.