Effect of (Co_(1/3)Sb_(2/3)) complex doping on the structure and electrical properties of 0.96(K_(0.49)Na_(0.51))(Nb_(0.97)Ta_(0.03))O_3-0.04Bi_(0.5)Na_(0.5)ZrO_3 lead-free piezoelectric ceramics

摘要

0.96(K_(0.49)Na_(0.51))(Nb_(0.97)Ta_(0.03))O_3-0.04Bi_(0.5)Na_(0.5)ZrO_3 (abbreviated as 0.96KNNT-CS_x-0.04BNZ, x = 0.000, 0.002, 0.004, 0.006, 0.008, 0.010) lead-free piezoelectric ceramics were prepared via a solid state reaction method. The effect of (Co_(1/3)Sb_(2/3)) doping amount x on the structure and electrical properties of the ceramics was investigated. The XRD patterns showed the formation of a pure perovskite structure with the coexistence of orthorhombic and tetragonal phases over the whole compositions. However, the vibrational modes slightly shift towards lower frequencies with the increase of x value in the Raman scattering spectra, indicating that the (Co_(1/3)Sb_(2/3)) should be incorporated into the perovskite lattice. The optimal electrical properties obtained in the ceramics with x = 0.008 were as follows: piezoelectric coefficient d_(33) - 3A1 pC/N, planar electromechanical coupling coefficient kp = 42.9 %, mechanical quality factor Qm = 47, dielectric permittivity ε_(33)~T/ε_0 = 1435, dielectric loss tanδ = 2.7 %, and Curie temperature T_c = 303 ℃.