Enhancing piezoelectric properties of BCZT ceramics by Sr and Sn co-doping

• Pure perovskite Sr and Sn co-doped BCZT ceramics were successfully synthesized.
• The Sr and Sn co-doped BCZT ceramics exhibit improved electrical properties.
• The Sr and Sn co-doped BCZT ceramics exhibit good thermal stability within the common usage temperature.
• The Sr and Sn co-doped BCZT ceramics is promising for piezoelectric applications.

1 mol% Sr and 1 mol% Sn co-doped (Ba0.84Ca0.15Sr0.01)(Ti0.90Zr0.09Sn0.01)O3 (BCSTZS) ceramics were prepared by the conventional solid-state reaction method. The sintered BCSTZS ceramics exhibit pure perovskite structure with composition locating at the rhombohedral side around the morphotropic phase boundary (MPB) of the BCZT system. With the increase of sintering temperature, the grains grow up, porosity eliminates and microstructure becomes dense accompanied by the improvement of electrical properties of the synthesized BCSTZS ceramics. Although the grain size of the BCSTZS ceramics sintered at elevated temperatures is rather “small”, they still exhibit excellent electrical properties, which can be attributed to the MPB effect and the dense microstructure induced by the Sr and Sn co-doping. The BCSTZS ceramics sintered at 1550 °C exhibit improved thermal stability of the piezoelectric and ferroelectric properties within the common usage temperatures, indicating that the BCSTZS ceramics are promising lead-free candidates for the widely used lead-based piezoelectric materials.