Synthesis and electrical properties of CeO2-added (Na0.5Bi0.5)0.94Ba0.06TiO3 ceramics

(Na0.5Bi0.5)0.94Ba0.06TiO3-xwt.%CeO2 (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) powders were synthesis by a citrate method, and the piezoelectric and ferroelectric properties of the ceramics were investigated. The results indicate that the citrate method is an advantageous route in producing (Na0.5Bi0.5)0.94Ba0.06TiO3-xwt.%CeO2 (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) ceramics. Homogeneous and fine powders with a pure perovskite structure were derived from precursor solutions with a mole ration of citric acid to total metal cation content (C/M) of 1.3 by calcining at 650 °C for 1 h. The sample containing 0.6 wt.%CeO2 made by the citrate method shows superior piezoelectric properties and a strong ferroelectricity: high piezoelectric constant (d33 = 157 pC/N), high electromechanical coupling factor (kp = 31.2%), enhanced dielectric constant (ε33T/εo = 819) and relatively low dissipation factor (tan δ = 2.72%) at 1 kHz, corresponding to a relatively large remanent polarization of Pr = 38.0 μC/cm2 and a relatively low coercive field of Ec = 37.4 kV/cm.