Hydrothermal synthesis of titanium dioxides from peroxotitanate solution using basic additive and their photocatalytic activity on the decomposition of orange II

Nanosized TiO2 particles were prepared by hydrothermal method of the amorphous powders, which were precipitated in an aqueous peroxotitanate solution. The physical properties of prepared nanosized TiO2 particles were investigated. We also examined the activity of TiO2 particles as a photocatalyst on the decomposition of orange II. The particle size increases from 9 to 25 nm as the initial pH of the solution changes from 2 to 12. The titania particles prepared at pH=2 show the highest activity and the titania particles calcined at 400 °C also show the highest activity on the photocatalytic decomposition of orange II.