Ce对Na_(0.5)Bi_(0.5)TiO_3粉体的掺杂和扩渗改性研究  

Enhancement of electrical properties of Na_(0.5)Bi_(0.5)TiO_3 powders by Ce doping and Ce penetration

作　　者：郝素娥[1] 付东升[1] 米南[1] 李佳龙[1] 强亮生[1] 

机构地区：[1]哈尔滨工业大学化学系,哈尔滨150001

出　　处：《材料科学与工艺》2012年第5期31-34,42,共5页Materials Science and Technology

基　　金：国家自然科学基金资助项目(20571020)

摘　　要：为改善Na0.5Bi0.5TiO3材料的电性能,采用溶胶-凝胶法制备了Na0.5Bi0.5TiO3粉体.通过液相Ce掺杂和气相Ce扩渗两种方法,对Na0.5Bi0.5TiO3粉体进行了改性,采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、阻抗分析仪和电阻仪对改性前后Na0.5Bi0.5TiO3粉体的组成、结构和电性能的变化进行了研究.结果表明:Ce元素的添加有助于Na0.5Bi0.5TiO3粉体电阻率的降低,而扩渗改性使电阻率的降低更为显著,经600℃扩渗的Na0.5Bi0.5TiO3粉体的电阻率由3.71×106Ω.m降至2.39×101Ω.m;稀土Ce掺杂使Na0.5Bi0.5TiO3的介电常数减小,而Ce扩渗使Na0.5Bi0.5TiO3的介电常数显著增大;Ce掺杂使粒径更加均匀,而随着气相扩渗温度的提高,晶粒粒径逐渐变大;Ce掺杂没有改变Na0.5Bi0.5TiO3的主晶相结构,但Na0.5Bi0.5TiO3粉体经Ce扩渗后,出现了单质Bi及Bi2Ti2O7、Na2Ti9O19、Na2Ti6O13的特征峰.For improving the electrical conductivity of Na0.5 Bi0.5 TiO3 （NBT） powders, the pure NBT powders were produced by sol-gel method and modified by Ce liquid doping and Ce gaseous penetration. The effect of modification on the constitution,structure and electrical properties of Ce-modified Na0.5 Bi0. 5 TiO3 powders was studied by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, impedance analyzer and resistance meter. The results showed that the addition of Ce helped to reduce the resistivity of Na0.5 Bio. 5 TiO3 powders, and the penetration method broughtl the lower resistivity than the doping method. The resistivity of Ce-modified Na0.sBio.sTiO3 powders penetrated at 600 ℃ was the lowest,which was decreased to 2.39 × 101 Ω · m from 3.71 × 106 Ω · m. The doping method made the dielectric constant of Na0.5 Bi0.5 TiO3 powders decreased, but the penetration method had the reverse effect. The Ce-doped Na0.5 Bi0.5 TiO3 powders had homogeneous finest particle size, and the particle size of the Ce-penetrated Na0. 5 Bio. 5 TiO3 powders was progressed with the penetration temperature increasing. The doping method did not change the main crystalline phases. But the new phases of Bi, Bi2Ti2OT, Na2Ti9019 and Na2Ti6013 were detected in the Ce-penetrated Na0.5Bi0.5TiO3 powders.

关 键 词：钛酸铋钠 气相扩渗 液相掺杂 CE 改性 电性能 

分 类 号：O614.23[理学—无机化学] O614.33[理学—化学]