Dielectric and piezoelectric properties of cerium-doped (NaBi)0.49[ ]0.02Bi2Nb1.98Ta0.02O9-based piezoceramics

The effect of Ce-substitution for A-site on the electrical properties of (NaBi)0.49[ ]0.02Bi2Nb1.98Ta0.02O9-based piezoceramics prepared by the conventional solid state sintering method was investigated. The dense microstructure with ~98% theoretical density was well developed in this material system, presenting a typical Aurivillius phase structure. The Curie temperature (TC) gradually decreases from 791 °C to 770 °C with increasing Ce3+ content. Moreover, doping with Ce3+ significantly increases the piezoelectric constant (d33) and decreases the coercive field. The (NaBi0.92Ce0.08)0.49[ ]0.02Bi2Nb1.98Ta0.02O9 ceramic exhibits optimum electrical properties (e.g., d33~24 pC/N, kp~8.4%, Qm~3488), together with a relatively high TC (~776 °C). These results indicate that this ceramic is a promising candidate for high-temperature piezoelectric applications.