Structural and electric properties of Ce-doped Na0.5Bi4.5Ti4O15piezoceramics with high Curie temperatures

Na0.5Bi4.5-xCexTi4O15(x = 0, 0.02, 0.04, 0.06, 0.08, 0.10) lead-free piezoelectric ceramics with high Curie temperatures are fabricated using the conventional solid-phase method. The effects of the Ce content on the phase structures, morphologies, and electrical properties of the Na(0.5)Bi(4.5-)(x)Ce(x)Ti(4)O(15)ceramics are systematically investigated. The appropriate content of Ce increasesb/aandc/aand induces the distortion of the crystal structure. The increasedb/aleads to a transverse asymmetry of the Na(0.5)Bi(4.5-)(x)Ce(x)Ti(4)O(15)ceramics, which facilitates the dipole flipping, thus enhancing the piezoelectric properties (d(33) = 20 pC/N). Although the improvedc/aincreases the degree of tetragonality of the Na(0.5)Bi(4.5-)(x)Ce(x)Ti(4)O(15)ceramic, which decreases the Curie temperature (T-C), theT(C)values of all samples are higher than 600 degrees C, considerably higher than the practical application temperature. The Ce doping significantly reduces the dielectric loss of the sample and increases its dielectric performance. The improvements in electric properties by the cerium doping can expand its use in high-temperature environments for oilfield logging, aerospace, and military applications.