Photocatalytic Activity of WO3/TiO2 for the Oxidation Reaction in Aqueous Solution and Gas Phase

초록

Photocatalytic activity of TiO2 toward the decomposition of 1,4-dichlorobenzene aqueous solution can be greatly improved by the loading of WO3 on TiO2 surface. In this work, we have investigated the role of WO3 in improving the photocatalytic activity of TiO2. The surface structure of WO3/TiO2 was characterized from the surface acidity measurement and surface analysis with XPS and TEM techniques. It has been found that WO3 is covered on the surface of TiO2 with monolayer thickness and the WO3/TiO2 particles present better dispersibility than pure TiO2 suspended in aqueous solution. We determined the kinetic parameters for these photocatalysts by applying Langmuir-Hinshelwood kinetic treatment. In order to avoid the difference in dispersibility for the aqueous suspension of these particles, we tested activity of photocatalysts as a film form. Gaseous 2-propanol was used as a model compound. WO3/TiO2 also shows much higher photocatalytic activity in decomposing 2-propanol, and it has been found that its decomposition route is quite different from that of pure TiO2. Detailed role of WO3 and the decomposition mechanism of 2-propanol were suggested in this work.