Synthesis and photocatalytic activity of TiO2 nanoparticles prepared by chemical vapor condensation method with different precursor concentration and residence time

Abstract

Nanosized TiO2 photocatalysts were synthesized using a chemical vapor condensation method under a range of synthesis conditions (precursor vapor concentration and residence time in a tubular electric furnace). X-ray diffraction showed that the prepared TiO2 powders consisted mainly of anatase (>94%) with a small amount of rutile. The mean particle diameter from the Brunauer-Emmett-Teller surface area and transmission electron microscopy measurements ranged from 9.4 to 16.6 nm. The specific surface area (92.5-163.5 m(2) g(-1)) of the prepared TiO2 powders was found to be dependent on the synthesis conditions. The content of hydroxyl groups on the surface of the prepared TiO2 sample was higher than those on commercial TiO2, resulting in increased photocatalytic oxidation. The photocatalytic activity of the TiO2 samples prepared in a methylene blue solution was strongly dependent on the crystallinity and specific surface area, which were affected by the TTIP vapor concentration and residence time. (C) 2011 Elsevier Inc. All rights reserved.