Effect of CeO2 addition on structure and electrical properties of (Na0.5Bi0.5)0.93Ba0.07TiO3 ceramics prepared by citric method

(Na0.5Bi0.5)(0.93)Ba0.07TiO3 ceramics added with 0-0.8 wt.% CeO2 were prepared by a citrate method, and the influence of the CeO2 addition on the structure and electrical properties was investigated. The specimens containing various amounts of CeO2 show the coexistence of rhombohedral and tetragonal phases, with the relative content of the tetragonal phases gradually enhancing with increasing amount of CeO2. Compared with (Na0.5Bi0.5)(0.93)Ba0.07TiO3, the specimen added with a small amount of CeO2 (<= 0.2 wt.%) display a slightly improved electromechanical coupling factor (k(p)) and piezoelectric constant (d(33)) in conjunction with a reduced dielectric loss (tg delta) and an enhanced mechanical quality factor (Q(m)), while higher CeO2 amounts led to a rapid deterioration of the piezoelectric and ferroelectfic properties. The variation of the electrical properties with the CeO2 addition was tentatively interpreted with respect to doping effect, crystal-structural evolution and stability of ferroelectric domains. (C) 2007 Elsevier Ltd. All fights reserved.