微乳液化学剪裁制备纳米钛酸钡和二氧化钛

Preparation of BaTiO_3 and TiO_2 Nanoparticles in Microemulsions by Chemical Tailoring

以钛酸丁酯、氢氧化钡和正己醇制备凝胶,用吐温-80/正已醇/环己烷/水制成W/O型微乳液在25,℃下进行化学剪裁,将前驱物在550,℃下煅烧,分别制备出了纳米钛酸钡和纳米二氧化钛.对产物进行X-射线粉末衍射(XRD)、透射电镜(TEM)、红外(IR)和差热(DTA)分析,研究了煅烧温度对BaTiO3和TiO2纳米质点粒径和组成的影响.结果表明,最好的煅烧温度是550,℃.所得纳米钛酸钡为具有较好晶型的六方晶体,粒径在30～42,nm之间,钡钛摩尔比为1∶1;纳米二氧化钛为单一的锐钛矿型八面体结构,平均粒径小于50,nm.实验表明,通过凝胶-微乳液法合成的纳米物质可以有效地减少团聚,控制微粒的组成和粒径,且操作简单,成本低.

Preparation of nano-scale barium titanate and titanium dioxide with sol-gel and microemulsion chemical tailor- ing technologies was investigated. Sol-gel was prepared with the tetrabutyl titanate, barium hydroxide and n-hexanol,then BaTiO3 and TiOz nanoparticles were synthesized respectively in Tween-80/n-hexanol/cyclohexane/water quaternary reverse microemulsion by chemical tailoring at 25℃ with the precursor calcinedat 550℃, The products were characterized by XRD, TEM, IR and DTA and the effects of the calcination temperature on the diameters and composing of BaTiO3 and TiO2 nanoparticles were studied. The results indicate that the optimal calcination temperature is 550 ~C ;the diameters of the prepared BaTiO3 and TiO2 nanoparticles with a cubic phase and a single crystal are approximately 30---42 nm and less than 50 nm, respectively. And the molar ratio of barium to titanium of products is 1.0. The experiments indicate that the synthetical nano-material by sol-gel and microemulsion chemical tailoring technologies can decrease conglomeration effectively, control the composing and diameters of nanoparticles with simple operation and low cost.