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Titanium dioxide (titania) is a well known photocatalyst for its efficiency in dissociating pollutant organic compounds that are adsorbed on a particular surface. Polymer substrates have found their way in the semiconductor industry as a base layer for electronics and devices in nanotechnology as well as in sensor and actuator applications. The manipulation and use of these systems have the adverse side of dirtiness, hindering for times its correct functioning and also possibly cause the degradation of the polymer. Enhancing the photocatalytic efficiency and the mechanical properties of titania has become a major concern for the authors, bearing in mind industrial applications for general purpose plastics. TiO2 thin films have been deposited by unbalanced reactive magnetron sputtering from a high purity Ti target in an Ar/O2 atmosphere, at room temperature on polymer sheets, such as PVDF, Polycarbonate and TrFG. The photocatalytic behaviour of the titania coatings was determined by combined ultra-violet irradiation and absorption measurements. The observed photo-decomposition of the aqueous solution (organic dye), acting as a pollutant, was measured in the UV/Vis spectrum by the decrease of the maximum absorbance with irradiation time. Analysis of the absorption data allowed us to obtain the decrease in concentration as a function of time to be observed. In order to assess the mechanical behaviour of the as-sputtered films, the film/substrate composite system was loaded unidirectionally using a tensile testing machine. The relation between the measured crack density and the applied strain has been used to characterize the film strength and relate it with the titania photocatalytic efficiency. |