中文摘要：

以五水硝酸铋（Bi（NO3）3·5H2O）、水合硝酸镧（La（NO3）3·nH2O）和钛酸四丁酯（（C4H9O）4Ti）为原料，氨水为沉淀剂，分两步沉淀Ti离子和Bi、La离子，利用沉淀法合成了Bi3.25La0.75Ti3O12（BLT）粉体。利用差热分析（DTA）和热失重（TG）对两步沉淀法制备的前驱体粉体的热行为进行了分析，用X射线衍射（XRD）研究了其晶相演化过程，利用场发射扫描电子显微镜（FESEM）对BLT粉体粒度和形貌进行了观察。结果显示两步法制备的前驱体粉体经低温煅烧直接转化为单一的铋层状钙钛矿相BLT粉体，在700℃煅烧2h合成的BLT粉体颗粒不大于100nm，颗粒间结合疏松，具有良好的分散性。

英文摘要：

The fine powders of Bi3.25La0.75Ti3O12 （BLT） were prepared by a two-step precipitaton route. Starting materials used were chemical grade bismuth nitrate（Bi（NO3）3.5H2O）, lanthanum nitrate（La（NO3）3-nH2O） and tetrabutyl titanate （（CaH9O）4Ti）. The differential thermal and thermo-gravimetric analysis were used to investigate the thermal behavior of BLT precursor powders and X-ray diffraction was employed to evaluate the phase evolution. Field emission scanning electron microscopy （FESEM） was employed to observe the particle size and morphology of the BLT powders. The results show that a single phase of Bi-layered perovskite structure BLT powders can be synthesized by calcining the precursor powders. After calcinations at 700 ℃for 2 h, the particle size of the BLT powder is less than 100 nm, and loose powders with good dispersability are obtained.