Simultaneously achieved high piezoelectricity and resistivity in CaBi₂Nb₂O₉-based ceramics with high curie temperature

To guarantee the functional operation of high-temperature piezoceramics in harsh circumstances, both large piezoelectricity and superior resistivity are prerequisites. However, it remains a formidable challenge to achieve these objects. Herein, we report Ce-doped CaBi2Nb2O9-based high-temperature polycrystals, which can simultaneously deliver a high piezoelectric coefficient d(33) of 21.8 pC/N and decent resistivity rho of 7.1 x 10(7) Omega cm at 500 degrees C, along with a high Curie temperature of 916 degrees C. More encouragingly, the materials are also gifted with exceptional thermal stability (< 10% variation of d(33) in a broad range from ambient temperature up to 900 degrees C). In-depth multiscale structural characterizations unveil that the outstanding comprehensive performance of Ce-doped CaBi2Nb2O9-based ceramics originate from the synergistic effects of refined grain size and domain morphology, and reduced defect concentration. This work not only demonstrates that CaBi2Nb2O9-based ceramics hold enormous potential for high-temperature implements, but also offers prospects to exploit high-performance high-temperature piezoceramics.