CeO2掺杂(Bi0.5Na0.5)0.94Ba0.06TiO3压电陶瓷的电子性能与微观结构

采用传统陶瓷工艺制备了CeO2掺杂(Bi0.5Na0.5)0.94Ba0.06TiO3(缩写为 BNBT6)无铅压电陶瓷.研究了CeO2掺杂量(0～1.0wt%)对BNBT6陶瓷的密度、相结构、微观结构及介电与压电性能的影响.XRD表明,CeO2掺杂量在0～1.0%wt之间变化,没有改变BNBT6陶瓷纯的钙钛矿结构.SEM表明,少量的CeO2掺杂，改变了陶瓷的微观结构.介电温谱表明,随着CeO2掺杂量的增加,铁电相向反铁电相转变温度(Td)降低. 室温下,CeO2掺杂量为0.4wt%时，BNBT6陶瓷样品有很好的性能:密度为5.836g/cm3,压电常数为136pC/N，平面机电藕合系数为30.3%, 相对介电常数为891, 介电损耗为0.0185.

ELECTRICAL PROPERTIES AND MICROSTRUCTURE OF CeO_2-DOPED(Bi_(0.5)Na_(0.5))_(0.94)Ba_(0.06)TiO_3 PIEZOELECTRIC CERAMICS

CeO2-doped (Bi0.5Na0.5)0.94Ba0.06TiO3 (abbreviated as BNBT6) lead-free piezoelectric ceramics (0 ～1.0 wt %) were synthesized by conventional solid-state processes. X-ray diffraction (XRD) data shows that CeO2 diffuses into the lattice of (Bi0.5Na0.5)0.94Ba0.06TiO3 ceramics and forms pure perovskite phase. SEM images indicate that a small amount of CeO2 addition affects the microstructure. The temperature dependence of the dielectric constant and dissipation factor shows that the transition temperature from ferroelectric to antiferroelectric phase (Td) decreases with the addition of CeO2. At the room temperature, the ceramics doped with 0.4wt% CeO2 show quite good performance with high density ( =5.836g/cm3), high piezoelectric constant (d33=136pC/N), high coupling factor (kp = 0.303), high dielectric constant (εr=891) and low dissipation factor (tanδ=0.0185).