Microstructure and electrical properties in Zn-doped Ba0.85Ca0.15Ti0.90Zr0.10O3 piezoelectric ceramics

Piezoelectric ceramics doped with small amounts of elements usually cause significant improvement in piezoelectric properties. In this study, we prepared Ba0.85Ca0.15Ti0.90Zr0.10O3-x wt% ZnO (0 ⩽ x ⩽ 0.16) ceramics via a conventional solid-state reaction method. The evolution of domain structure, relaxor behavior, ferroelectric and piezoelectric properties with Zn doping was systematically investigated. The ceramics with x = 0.08 possess slender domain patterns and high domain wall density. The Ba0.85Ca0.15Ti0.90Zr0.10O3-8 wt% ZnO ceramics show maximum remnant polarization and spontaneous polarization (Pr = 10.14 μC/cm2, Ps = 19.68 μC/cm2). A giant piezoelectric coefficient of d33 = 603 pC/N and high planar electromechanical coupling factor of kp = 0.56 were obtained for the sample of x = 0.08, showing the potential possibilities for lead-free piezoelectric application.