The term photocatalysis is used to describe a photon-driven catalytic process. Titanium dioxide is a well-known
photocatalyst in such fields as self-cleaning material and anti-microbial effects. Besides these photocatalytic applications,
TiO<sub>2</sub> is a widely-used high index material for optical thin films.
In the present investigation, the photocatalytic activity of transparent TiO<sub>2</sub> thin films was optimized to achieve
multifunctional high precision optical coatings. The films have been deposited by ion assisted deposition (IAD), applying
a Leybold APS plasma source as well as a Denton CC-105 ion source. The cause-and-effect chain between the use of
different parameters in the IAD process and optical properties of the TiO<sub>2</sub> layers as well as their photocatalytic activities
As test reaction for the determination of the photocatalytic properties, the degradation of methylene blue (MB) was
chosen. The used setup based on a high precision two-path laser measurement system was developed by the LZH in
order to determine the kinetic performance of TiO<sub>2</sub> catalysts under well-defined UV illumination conditions. Photonic
efficiencies of the TiO<sub>2</sub> thin films were calculated from the obtained data. Additionally, crystal structure analysis has
been investigated for the identification of anatase and rutile modifications.
The comparison of the results shows that ion assisted deposition is an appropriate technology for the preparation of
photocatalytic active thin films for optical applications.