We report on the electrochemical/photoelectrochemical behaviour of commercial P25 titanium dioxide deposited onto fluor-doped tin oxide and stainless steel substrates via electrophoresis. An experimental design [1] was applied to find optimum conditions for the photoelectrochemical responses of such thin film layers. Adhesion strength of film coatings, and the fill factor (FF) were used as key parameters to compare the photoactivity of the semiconducting layers. Organic molecules such as carmine indigo in aqueous solution were used as representative water pollutants in a reactor containing six electrode plates. The UV lamp (black light blue, 6W, lambda = 365 nm) was used as an irradiation source for 8 h under continuous stirring conditions. The decolouration of the solution reached 87.5 % after 8 h. The total organic carbon (TOC) was measured. The results indicate that the mineralization of the carmine indigo was around 36 % after 8 hours. A comparative study was done using titanium dioxide deposited on paper (Ahlstrom) and stainless steel.

Acknowledgements:
This work was partially financed by the Aquati-Sol Project and region Poitou-Charentes, France.

References:
[1] Pedroza, A. M., Mosqueda, R., Alonso-Vante, N., Rodríguez-Vázquez, R. Chemosphere 67 (2007) 793.