Piezoelectric enhancement of 0.6Pb(Zr,Ti)O₃–0.4Pb(Ni_1/3Nb_2/3)O₃ ceramics with artificial MPB engineering

Piezoelectric materials are widely used in the direction of sensors. PZT-based ceramics are very suitable for precision sensors. However, due to the low Curie temperature, the application temperature range of the material is relatively narrow. Here we show a high-performance material 0.6PZT–0.4PNN. In this case, a morphotropic phase boundary (MPB) region was artificially designed in the 0.6Pb(Zr_xTi_1−x)O₃–0.4Pb(Ni_1/3Nb_2/3)O₃ (x = 0.35–0.41) ceramics to develop high-performance piezoelectric compositions which could cofire with low-cost Ag/Pd inner electrode by 0.2wt% Li₂CO₃ addition. The ceramic composition at x = 0.39 near MPB possess exceptional properties with high piezoelectric coefficient d₃₃ ∼ 611 pC/N, planar electromechanical coupling coefficient k_p ∼ 53.5%, low mechanical quality factor Q_m ∼ 64.5 piezoelectric strain of 0.17%, and suitable Curie temperature T_c ∼ 191 °C, respectively. The fact that d₃₃ was detected close to T_c, and no noticeable change below 6.6% in cycling stability was observed at 20 kV/cm means a robust temperature-independence and fatigue reliability of the piezoelectric ceramics. Thus, this research provides a novel high-piezoelectricity configuration with elemental regulation, comparable to the commercial PZTs.