Ultrahigh temperature stability in heterovalent-ion doped PZT ceramics

We achieved ultrahigh temperature stability of the piezoelectric coefficient d ₃₃ by doping heterovalent ions in the PbZr _0.54Ti _0.46O ₃ ceramics at the A/B sites in the ABO ₃ lattice. The Sm ³⁺-ion amount at the A-site remains constant, while the Ta ⁵⁺-ion amount at the B-site changes. We utilized electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS) to investigate the reduction of oxygen vacancies, which are closely associated with the defect dipoles formed by heterovalent doping. We utilized piezoresponse force microscopy (PFM), temperature-dependent X-ray diffraction (XRD) combined with Rietveld refinement, and temperature-dependent Raman spectroscopy to understand the mechanism of the temperature stability of the piezoelectric coefficient d ₃₃. When x = 0.01, the performance of xTa-0.01Sm-PbZr _0.54Ti _0.46O ₃ ceramic is optimal: d ₃₃ = 530 pC/N, electromechanical coupling factor k _p = 0.72, Curie temperature T _C = 343 °C, where the temperature stability of the piezoelectric coefficient is ultrahigh, and the d ₃₃ changes only 2.2 % over the 25–200 °C temperature range.