Improving the Piezoelectric Properties of CBN‐based Ceramic by a Ce Ion

CaBi2Nb2O9 (CBN), one of the bismuth-layered structural ferroelectrics, with high Curie temperature (T-C), has great potential in high-temperature applications. In this work, high Curie temperature and piezoelectric constant (d(33)) are realized in modified CaBi2Nb2O9 ceramics with Ce-substitution. Ce-substitution changes the crystal structures and domain structures of CBN-based ceramics, so as to improve the piezoelectric properties. The optimal performances are obtained with a high d(33) value (similar to 18.0 pC/N) and a T-C value (similar to 930 degrees C), together with a low tan delta value (similar to 0.028 at 500 degrees C). Moreover, the thermal stability is also enhanced, where the d(33) value maintains 93.9% of its original value after annealing at 900 degrees C for 2 h. Thus, these findings play a meaningful role in devices manufacturing, where the apply temperature is often more than 500 degrees C.