Preparation and characterization of photocatalytic TiO2/WO3 films on functionalized stainless steel.

In this study, both TiO₂ and WO₃ were synthetized using controlled hydrolysis followed by dialysis. The produced transparent emulsions were dried into powders. Then, TiO₂-WO₃ photocatalyst films were deposited by pulsed electrophoretic deposition. The substrates were made of stainless steel pre-functionalized in a conversion bath. The conversion layer played an important role in the adhesion of the composite film into the substrate. Film surface morphology, crystallinity, roughness, thickness, and elemental composition were determined from XRD, optical profilometry and SEM-EDX measurements. The mechanical properties were resolute by nano-indentation test and adhesion was investigated using a scratch test. The photocatalytic decolorization of the Amido Black-10B dye was studied over TiO₂-WO₃ coatings under UV irradiation. TiO₂ film doped 5% WO₃ film exhibited the best photocatalytic activity due to its crystalline size and three-phase structure as well as a synergetic effect of TiO₂-Fe₂O₃ and TiO₂-WO₃. This film showed also good adhesion properties. [ABSTRACT FROM AUTHOR]