The effect of preparation method on the photoactivity of crystalline titanium dioxide particles

The present study shows that acidic conditions during the hydrolysis and condensation of titanium isopropoxide as well as a high water to alkoxide ratio result in crystalline TiO2 precipitates. Nanosized rutile and anatase particles were prepared at relatively low temperatures (<100 degreesC) and atmospheric pressure. The crystalline particles exhibited improved photocatalytic activity to particles prepared using the conventional alkoxide method. Surface cleanliness of the prepared particles was found to be highly influential on the photoactivity of the catalyst. The extent and type of washing was found to affect the surface properties of the particles. X-ray diffractometry, photon correlation spectroscopy (PCS), Brunauer-Emmett-Teller (BET) surface area analysis and transmission electron microscopy (TEM) were used to characterise the powders. (C) 2003 Elsevier Science B.V. All rights reserved.