Carbon-coated TiO2 photocatalysts were prepared by a simple heat treatment of the powder mixtures
of anatase-type TiO2 with PVA at a temperature of 700 and 900 oC in a N2 atomosphere. Diffuse optical
reflectance spectra for carbon-coated TiO2 showed the absorption edge for anatase structure clearly, overlapping
with absorption due to coated carbon over whole range of wavelegth. These carbon-coated TiO2 photocatalysts
had relatively high apparent BET surface area, from 50 to 170 m2/g, which suggested the formation of porous
carbon layers, and showed relatively high adsorption of various pollutants, methylene blue (MB), reactive black
(RB-5), phenol (Ph) and iminoctadine triacetate (IT), in water. Photocatalytic activity of carbon-coated TiO2 thus
prepared was evaluated through the determination of the rate constant for the decomposition of different
pollutants in water. Rate constant values were strongly depend on the pollutants, but their dependence on the
crystallinity of TiO2 phase. The relations between adsorptivity and rate constant for four pollutants looked
similar with each other, and the pollutants adsorbed in the larger amount was decomposed with the higher rate.
Adsorptivity of carbon-coated TiO2 photocatlysts was determined and discussed on the relations to BET surface
area, amount of carbon coated and also rate constant k for the decomposition of MB, RB5, Ph and IT.
Adsorptivity of carbon-coated catalysts depends strongly on the adsorbate (pollutant) but also on the surface
nature of carbon layer on TiO2 particles. The relations between adsorptivity and rate constant k for four
pollutants looked similar, suggesting that the pollutant adsorbed in the larger amount being decomposed with the
higher rate.
On the Possibility of Surface Modification of an Alumina Support with Amphiphilic Carbonaceous Material
