New anatase photocatalysts have been prepared by a hydrothermal technique.
The powders have been shown to have a high photocatalytic activity, which i
s believed to be derived from their high crystallinity and phase purity res
ulting in fewer defects that can allow pre-emptive recombination of the fre
e electron and positive hole. Bi-phasic particles containing both the anata
se and brookite phases have also been prepared, but these have much lower p
hotocatalytic activity. (C) 2001 Kluwer Academic Publishers.