Characterization of chemically- and physically-derived nanophase titanium dioxide

Abstract

A solution-based processing method has been used to synthesize nanocrystalline TiO 2 powder. By doping with a small amount of Sn, the rutile phase is formed with an average grain size < 20 nm. These powders can be hot-pressed into pellets of > 95% theoretical bulk density while maintaining an average grain size between 30–50 nm. Other pellets have been prepared similarly using powder synthesized by the inert gas condensation process. Here we report on the characterization of both types of nanophase TiO 2 by x-ray diffraction and transmission electron microscopy. While the physically-derived samples have somewhat finer grain sizes, the Sn-doped chemically-derived samples are more readily densified, appear to be highly stoichiometric, and are free of the anatase phase.