Preparation of nanocrystalline titanium dioxide fibers using sol-gel method and centrifugal spinning

This paper reports the study of the preparation and structural characterization of nanocrystalline titanium dioxide (TiO2) fibers, which were prepared using sol-gel method with titanium tetrachloride (TiCl4) as the titanium source and acetylacetone as chelating agent to synthesize the poly-acetylacetonatotitanium (PAT) spinning solution, followed by centrifugal spinning and steam atmosphere heat-treatment. The molecule structure of the PAT was analyzed. Using the fourier transform infrared and H-1 nuclear magnetic resonance spectrum. The microstructure of the TiO2 fibers was observed by using scanning electron microscope, which showed that the fibers' diameters are in the range of 5-15 mu m. The effects of the SiO2 doping were investigated by using high-resolution transmission electron microscope and X-ray diffractometer, and the conclusion is that SiO2 doping can efficiently inhibit the grain growth of TiO2 fibers and defer the phase transformation of anatase-to-rutile. In fact, the grain size is 33.2 nm for the un-doped TiO2 fibers heat-treated at 700 A degrees C, while the grain size is only 7.6 nm for the TiO2 fibers doped with 15 wt% SiO2, which shows the possibility to obtain nano-crystalline anatase TiO2 fibers at higher heat-treatment temperature.