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

Abstract

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 1H 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 μm. 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 °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.