Modeling TiO2: insights into photocatalytic material properties and reactions

Titania is an industrially well known material, which is commonly used as a cost- efficient pigment in sun screens or paints. Additionally to this application, titania is one of the most frequently applied photo-catalysts in water and air purification. However, its utilization in photo-chemistry is up-until date still not satisfactorily ex- plored. Especially the fact, that titania’s three phases, anatase, rutile and brookite, show photo-induced electron-hole pair formation in their pristine form only under ultra violet (UV) irradiation, renders most utilization of titania as a photo-catalyst in- efficient for large-scale applications. Therefore, ways to improve the photo-catalytic activity of Titania are being sought. Despite the discussion of a variety of different approaches to achieve the same, to date no convincing methods have been found that can adequately enhance TiO2s photocatalytic efficiency or are not yet explored satisfactorily. Based on these challenges, the work presented in this thesis set out to explore three different approaches for enhancement, which will be introduced in the following.