| Abstract Scope |
Calcium bismuth niobate (CaBi2Nb2O9) is a promising ceramic material for high-temperature piezoelectric applications due to its high-Curie-temperature (TC) of 940 ℃. However, its practical use is limited by its poor piezoelectric performance and low direct-current electrical resistivity at elevated temperatures. In this study, we introduced pseudo-tetragonal distortion into CaBi2Nb2O9 by substituting rare-earth ions to reduce domain wall energy, facilitate domain switching, and decrease the presence of oxygen vacancies. These benefits significantly improve both the piezoelectric performance and dc electrical resistivity of the material. To further enhance piezoelectric performance, we prepared textured rare-earth-substituted CaBi2Nb2O9 ceramics with a Lotgering factor of up to 90% using a two-step spark plasma sintering method. The textured CaBi2Nb2O9 ceramics exhibited superior piezoelectric performance, with a piezoelectric constant of 30 pC/N, four times higher than that of CaBi2Nb2O9. Importantly, these textured ceramics maintained excellent electrical properties at elevated temperatures, suggesting their suitability for high-temperature piezoelectric device applications. |