Effects of SmCoO3 on the microstructure and piezoelectric properties of (Bi0.5Na0.5)0.94Ba0.06TiO3 ceramics

(Bi0.5Na0.5)0.94Ba0.06TiO3 (abbreviated to BNBT6) ceramics doped with 0–0.6 mol.% SmCoO3 were synthesized by the conventional solid-state reaction method, and the effect of SmCoO3 addition on the dielectric and piezoelectric properties was investigated. X-ray diffraction (XRD) patterns show that SmCoO3 diffuses into the lattice of the BNBT6 ceramics to form a solid solution with a pure perovskite structure. SEM images indicate that the addition of SmCoO3 caused a remarkably promoted grain growth. Our results reveal that both the piezoelectric and electromechanical properties of BNBT6 ceramics could be greatly improved by certain amount of SmCoO3 substitutions. At room temperature, the BNBT6 ceramics doped with 0.4 mol.% SmCoO3 exhibit the optimum properties with high piezoelectric constant (d33=144 pC/N), high planar coupling factor (kp=29.1%), and high mechanical quality factor (Qm=219).