Effects of cerium on structures and electrical properties of (Nb, Ta) modified Bi4Ti3O12 piezoelectric ceramics

Bi4Ti3O12 high‐temperature piezoelectric ceramics composed of 0.03 mol (Nb, Ta)5+ substituting B site and x mol CeO2 (x = 0–0.05, abbreviated as BCTNT100x) substituting A site were synthesized by the conventional solid‐state reaction method. The effects of Ce additive on the structures and electrical properties of resulting Bi4Ti3O12‐based ceramics were systematically investigated. In‐situ temperature‐dependent X‐ray diffraction (XRD) confirmed that the phase structure of BCTNT100x ceramics change from orthorhombic structure to tetragonal structure as temperature increased. The ceramics at Ce content x = 0.03 illustrated optimal performances with superior piezoelectric constant (d33 = 36.5 pC/N), high Curie temperature (TC = 649 °C), and large remanent polarization (2Pr = 21.6 μC/cm2). BCTNT3 ceramics also possessed high d33 of 32.5 pC/N at an annealing temperature of 600°C, with electrical resistivity preserved at 106 Ω cm at 500 °C. These results demonstrate that BCTNT100x ceramics can be used as high‐temperature piezoelectric devices.