Photocatalytic oxidation of soot by P25 TiO2 films

The photomineralisation of soot by P25 titania films is studied using FT-IR and the process shown to involve the oxidation of carbon to CO2 exclusively. The efficiency of this process is low, however, with a formal quantum efficiency of 1.1 × 10−4 molecules of carbon oxidized per incident photon of UVA light. The cause of this low efficiency is attributed largely to the less than intimate contact between the fibrous soot layer and the surface of the photocatalyst.