Poling above the Curie temperature driven large enhancement in piezoelectric performance of Mn doped PZT-based piezoceramics

Abstract

The enhancement of piezoelectricity is usually in sacrifice of Curie temperature, which in turn limits its working temperature range. It is well known that there are some trade-off among the various performance parameters of most piezoelectric ceramics, and it is still difficult to achieve synergistic improvement in multiple parameters. Here, it is reported that the piezoelectric coefficient d33 of a 0.6 mol% Mn-doped Pb(Sb0.5Nb0.5)0.02Zr0.51Ti0.47O3 piezoelectric ceramics is increased to 436 pC N−1, and its electro-strain can reach 0.16% (d33* = 800 pm/V) at 2 kV mm− 1 by high-temperature poling, whose Curie temperature can still keep at 347 ℃. The features of "hard" piezoelectric ceramics such as low dielectric loss (tgδ = 0.23%) and high mechanical quality factor (Qm = 546) are also preserved. Through structural characterization, combined with the theoretical results of phase field simulation, it is shown that its excellent piezoelectric performance originates from the highly oriented domain structure and small domain size after high temperature poling. On the other hand, the valence state transition of Mn3+ ions during high-temperature poling increases the defect vacancies and lattice distortion in ceramics, which keeps the acceptor-doped characteristic of the ceramics.