金红石型纳米二氧化钛合成及晶貌控制

Synthesis and Crystallographic Form-Controlled of Rutile Titania Nanoparticles by the Sol-Gel Method

采用溶胶-凝胶法制备了一系列锐钛矿型、金红石型和混晶纳米Ti O2,通过改变反应条件获得了具有不同形貌的金红石型样品。借助DTA-TG技术确定所得锐钛矿型向金红石型发生晶型转变的温度,在低于晶型转变的温度下焙烧系列纳米Ti O2样品,对样品用XRD、TEM、IR等技术进行了表征。研究表明,缓凝剂的加入不利于金红石型Ti O2的形成,钛原料浓度增大使样品中金红石型的含量增大,反应初期氨水的加入可加快体系中锐钛矿型Ti O2的生成,反应时间和陈化时间的延长有利于锐钛矿向金红石型的转变。

A series of anatase, rutile and mixed crystallographic form nano-titania samples method. The futile nano-titania samples with different shape were obtained by change were prepared by sol-gel reaction conditions. The crystallographic form transformation temperature from anatase to rutile was made certain by DSC-TG technology. The nano-titania samples were calcined under the crystallographic form transformation temperature and characterized by X-ray diffraction （ XRD ）, transmission electron microscope （TEM） and fourier transform infrared （FT-IR）. The results reveal that the accession of delayed coagulant makes against the constitute of rutile titania, and the aggrandizement of the titanium raw material concentration can increase the contens of the rutile titania. Prolonging reaction and ageing time avails the crystallographic form transformation from anatase to rutile. Adding ammonia to reaction system at the beginning of the reaction can expedite forming the anatase titania.