Photocatalytic oxidation of cyclohexane on ultra-fine TiO2 particles

Photocatalytic oxidation of cyclohexane has been investigated on nanometer size TiO2 particles under mild condition. Photocatalytic activity increases with decrease in particle size and depends on the type and the microstructure of crystallites. The selectivity of the product (cyclohexanol) is very high (greater than or equal to 85%). The results suggest that a size quantization effect is operating and reduction of size might result in some electronic modification of TiO2 to produce an enhancement of the activities of electrons and holes.