BaTiO_3纳米晶的合成与表征

Synthesis and Characterization of BaTiO_3 Nanocrystals

以硬脂酸、硬脂酸钡和钛酸丁酯为原料合成了ＢａＴｉＯ３纳米晶，粒度为１０～２０ｎｍ，烧成温度为６５０℃，低于传统的合成温度。用红外光谱、差热分析、热重分析和Ｘ射线衍射对合成过程进行了研究，用透射电镜考察纳米晶的粒度和形貌。用发射光谱和Ｘ射线荧光光谱对样品纯度进行了分析。结果表明，此法合成的纳米晶ＢａＴｉＯ３纯度高、粒度小且较均匀，在常温下属立方钙钛矿型。

BaTiO3 nanocrystals were synthesized by stearic acid-gel methd(SAG) ,using stearic acid, barium stearate and tetrabutyl titanate as raw materials. The synthesis temperature was 650℃ and the formation temperature of perovskites oxide was 950℃ by conventional solid phase reaction method. The transformations of precursor compound to gel and to crystalline phase were characterized by infrared spectroscopy,differential thermal analysis and thermogravimatric analysis. The nanocrystalline BaTiO3 samples were characterized by transmission electron microscope(TEM) and X-ray diffraction. Powders were further analyzed by optical emission spectroscopy and X-ray fluorescence techniques to determine impurity contents and Ba:Ti ratios. Using this synthesis method,small size and high purity BaTiO3 nanocrystal could be obtained.