The Synthesis And Characterization Of TiO₂ And SiO₂ Microwires And Nanowires

High-purity rutile TiO₂ (and SiO₂) microwires arrays and nanowires were synthesized by sol-gel method with titanate isopropylateor as Ti resource, (TEOS as the Si resource,) absolute alcohol as solvent, bamboo charcoal as template. Different heat temperature, heat time and meshes of the template were used to study the growth process of the prepared one-dimension nanomaterials. Investigations of morphology and crystalline structure of the template and the products were made on the scan electron microscopy (SEM), electron diffraction spectra (ED), transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS).SEM images show that there are plenty of microporoes with straight channels in bamboo charcoal. And XRD pattern illustrates that bamboo charcoal can be removed simply and conveniently by heating in air. It suggests that it is possible for bamboo charcoal to be the template inpreparation of one-dimension nanomaterials.XRD studies of the samples Tn (n=1⁷) show the resulting products that obtained decarbonized followed at 1200℃ for 2h in Ar atmosphere, were high-purity rutile phase TiO₂. TEM result shows that the product is a mixture of high-ordered microwires with diameter of l²Î¼m and length over 250μm and nanowires, which have diameter of about 20⁵0nm and hundreds of nanometers length. The growth process of the TiO₂ one-dimension nanomaterials is discussed. The results suggest that the micropores of the bamboo charcoal may perform main template function. Different sintering temperatures and time were used to study the influence of the forming process of TiO₂ nanowires. It is shown that the samples tend to form rutile TiO₂ one-dimension nanomaterials with the sintering temperature rising. XPS results show that the surface of TiO₂ nanowires were composed of Ti, O, C, K, S elements, and Ti:O(mole ratio)=1:2.The SEM and TEM results of the samples Sn (n=1⁶) show that the SiO₂ products obtained decarbonized followed at 1250℃ for lh in Ar atmosphere, were high-ordered SiO₂ microwire arrays with the diameter of 1²Î¼m and length over 200μm, which copied to the structure of micropore precisely. It suggests that the micropores of the bamboo charcoal may perform main template function. When use bamboo charcoal powder as template, high-purity cristobalite SiO₂ nanowires with diameter of 150²00nm were obtained. XPS spectra show that the surface of nanowires...