Hydrothermal synthesis and piezoelectric property of Ta-doping K_(0.5)Na_(0.5)NbO_3 lead-free piezoelectric ceramic

摘要

Ta-doping K_(0.5)Na_(0.5)Nb_(1-x)Ta_xO_3 (x = 0.1, 0.2, 0.3, 0.4) powder was synthesized by hydrothermal approach and its ceramics were prepared after sintering and polarizing treatment in this work. The K_(0.5)Na_(0.5)Nb_(0.7)Ta_(0.3)O_3 ceramics near morphotropic phase boundary (MPB), which exhibited optimum piezoelectric properties of d_(33) = 210 pC/N and good electromechanical coupling factors of K_p = 0.3. The domain structure has been observed from TEM images which indicates that the K_(0.5)Na_(0.5)Nb_(0.7)Ta_(0.3)O_3ceramics have good piezoelectric and ferroelectric properties for it is near the MPB.