A facile sol-gel process was used to prepare sheet-like SiO2/ZrO2 composites from zirconium oxychloride and diethoxydimethylsilane as the precursors in the absence of any surfactants.The process involves the oriented growth of SiO2/ZrO2 nanocomposites in the mixed solvent of water and n-propanol.Tetragonal zirconia (t-ZrO2) crystal was obtained by calcining dried sheet-like SiO2/ZrO2 gel at 500 ℃ in air for 2 h.The structure and morphology of the products were analyzed by means of X-ray diffraction,scanning electron microscopy,and transmission electron microscopy.The elemental composition of typical products was determined by means of energy-dispersive X-ray spectrometry.The chemical feature of dried SiO2/ZrO2 gel was analyzed using a Fourier transform infrared spectrometer.It has been found that SiO2/ZrO2 nanocomposite with a grain size of about 18 nm can be readily prepared by the solgel process.Si atom in the nanocomposite is chemically linked to Zr via Si-O-Zr bond; and it only affects the morphology of ZrO2 crystalline but does not lead to changes in the size and phase structure of tetragonal zirconia.The present approach may be extended to preparing other similar hierarchical structures of inorganic functional nanomaterials.%以氧氯化锆和二甲基二乙氧基硅烷为前驱体,在无任何表面活性剂的条件下,利用溶胶-凝胶法制备了片状SiO2/ZrO2复合材料.采用X射线衍射仪、扫描电镜、能谱仪、傅立叶变换红外光谱仪、透射电镜等分析了产物的结构和形貌,并探讨了SiO2/ZrO2纳米复合材料的取向生长机理.结果表明,在正丁醇和水的混合溶液中制备的SiO2/ZrO2纳米复合材料的粒径为18 nm,将干凝胶在500℃空气气氛中焙烧2h可以得到四方相片状氧化锆晶体.化合物中的硅原子通过Si-O-Zr化学键与锆原子相连；硅的引入仅影响氧化锆晶体的形貌,而不导致四方相氧化锆结构和尺寸的改变.本文所述方法可望拓展用于制备其他具有类似分级结构的无机功能纳米材料.
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