Simultaneously Achieving Large Piezoelectricity and Low Dielectric Loss in High-Temperature BiScO3-PbTiO3-Based Ceramics

High-temperaturepiezoelectric materials are pivotal to technologyapplications fields including defense, aerospace, nuclear energy,and oil well logging. However, the acquisition of excellent piezoelectricproperties is usually at the cost of temperature stability (reducedCurie temperature and increased high-temperature dielectric loss),which hinders the application of piezoelectric ceramics in harsh environments.In this study, we investigated the effect of Nb5+ donorand Mn2+/3+ acceptor doping on the dielectric and piezoelectricproperties of BiScO3-PbTiO3 (BS-PT)-basedceramics. In contrast to the acceptor doping, it was found that thedonor doping not only enhances the piezoelectric properties but alsoeffectively suppresses the dielectric loss at a high temperature byreducing the oxygen vacancy concentration. Eventually, we simultaneouslyattained an excellent piezoelectric performance (d (33) is 553 pC/N at room temperature and 1528 pC/N at 400 & DEG;C, respectively) and a low dielectric loss (less than 2% inthe temperature range of 150-300 & DEG;C) but still with ahigh Curie temperature (T (C) & SIM; 445 & DEG;C) in Nb5+-doped BS-PT ceramics. Furthermore, differentin situ measurements were used to demonstrate the remarkable temperaturestability up to a high depolarization temperature of & SIM;400 & DEG;C.This work represents significant progress in high-temperature piezoelectricmaterials and provides a guideline for future efforts on enhancingthe piezoelectricity and suppressing the dielectric loss at high temperature.