Electrical properties and temperature stability of high TC/TR-T Pb(In1/2Nb1/2)O3–Pb(Zn1/3Nb2/3)O3–PbTiO3 piezoelectric ceramics with compositions near the morphotropic phase boundary

Abstract

Three sets of ternary ceramics in the compositions of 0.35Pb(In1/2Nb1/2)O3–(0.65−y)Pb(Zn1/3Nb2/3)O3–yPbTiO3 (y = 0.22–0.29), 0.40Pb(In1/2Nb1/2)O3–(0.60–y)Pb(Zn1/3Nb2/3)O3–yPbTiO3 (y = 0.24–0.32), and 0.50Pb(In1/2Nb1/2)O3–(0.50–y)Pb(Zn1/3Nb2/3)O3–yPbTiO3 (y = 0.27–0.37) near the morphotropic phase boundary (MPB) were fabricated by a two-step solid-phase synthesis route. The structure, electrical properties, and temperature stability of piezoelectric ceramics were studied. Structural analysis revealed that all ceramics exhibited pure perovskite phase and dense microstructure. In our chosen compositions, the maximum piezoelectric coefficient d33 = 589 pC/N and electromechanical coupling factor kp = 0.59 are presented for 0.35PIN–0.40PZN–0.25PT, the highest rhombohedral to tetragonal phase transformation temperature TR-T on the order of 187 °C is observed in the 0.50PIN–0.23PZN–0.27PT composition with a Curie temperature TC = 269 °C, 0.40PIN–0.33PZN–0.27PT, and 0.40PIN–0.32PZN–0.28PT ceramics do not depolarize at temperatures up to 230 °C. Considering the relatively high TC (255 °C), d33 (523 pC/N) and good thermal stability, 0.40PIN–0.33PZN–0.27PT is very promising for high-temperature piezoelectric applications. On this basis, a property-composition diagram around MPB in PIN–PZN–PT system was also established.