Enhanced electrical properties in Nd and Ce co-doped CaBi4Ti4O15 high temperature piezoceramics

Lead-free piezoelectric material with excellent piezoelectric properties and high Curie temperature is necessary for practical applications. In this work, (Nd, Ce) co-doped CaBi4Ti4O15 (CBT) ceramics were prepared by the conventional solid-state reaction technique. The effect of (Nd, Ce) co-doping on the structure and resulting electrical properties of CBT ceramics was systematically investigated. The optimized comprehensive performances were obtained at x = 0.075 with a large piezoelectric coefficient (19 pC/N), a low dielectric loss (0.073%) and a high Curie temperature (794 degrees C). More importantly, the ceramic also maintained a very high resistance and a low dielectric loss even at 400 degrees C (rho = 2.5 x 10(8) Omega cm, tan delta = 1.96%) and the d(33) showed no sign of waning after annaled 400 degrees C, Which shows great potential for high temperature piezoelectric device applications. Related mechanisms for the enhancement of electrical properties were discussed.