Titania was deposited on glass fibers with a partial epoxy layer coating from a solution containing TiO2 nanoparticles at T = 90 °C, and the adsorption process was examined by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), Fourier transform infrared (FT-IR) spectroscopy, and photocatalytic activity measurements. XPS data demonstrated that about 25% of the surface was covered with TiO2 nanoparticles, with 10% on the epoxy layer and 15% on the glass body. It was found that TiO2 nanoparticles can be readily adsorbed on epoxy groups, whereas they have a low tendency to adsorb on carbon polymer chains. This difference can be attributed to the hydrogen bonding between the hydroxyl groups on the surface of TiO2 nanoparticles and the hydroxyl groups resulting from the acid-catalyzed epoxy ring opening. This hypothesis was verified by removing the epoxy groups on top through preheating of the fibers at 500 °C and studying the surface coverage after adsorption. In this case, TiO2 was adsorbed on about 15% of the surface, and none of the polymer layer was covered with nanoparticles. FT-IR, SEM, and photocatalytic activity measurements confirmed the XPS results.

Photocatalytic activity of different morphologies of tungsten oxide was investigated before and after platinum loading. Different shape particles of tungsten oxide were synthesized using peroxo tungstic acid solution as a basic precursor and different methods. The prepared materials were composed of nanoparticles, nanorods, and nanosheets that formed different morphologies. The results of photodegradation with isopropyl alcohol (IPA) under visible light showed that the samples composed of nanostructures with an average lateral thickness of 20 to 47 nm were more active than one composed of broad nanosheets with a thickness of 60 nm. The samples were loaded with a platinum cocatalyst. The results of photocatalytic evaluation of loaded samples showed that the photooxidation reaction of samples with a smaller feature was accelerated with a higher rate rather than one with broad nanosheets. We conclude that although loading of a cocatalyst promoted the photocatalytic activity, it is not capable of compensating for the morphology influence on the photocatalytic activity.

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The photocatalytic degradation of Reactive Blue 19 (RB19) dye has been studied using TiO2 nanofibre as the photocatalyst in aqueous solution under UV irradiation. Titanium dioxide nanofibre was prepared using a templating method with tetraisopropylorthotitanate as a precursor. The experiments were carried out in the presence of the TiO2 nanofibre, and the effects of pH and electron acceptors on the degradation process were investigated. In order to observe the quality of the aqueous solution, chemical oxygen demand (COD) measurements were also carried out before and after the treatments. The photocatalytic decomposition of RB19 was most efficient in acidic solution. With the addition of hydrogen peroxide and potassium persulphate, as electron acceptors, into illuminated TiO2 nanofibre suspensions, a synergistic effect was observed leading to an enhancement of the decolorization. From experimental results, under the condition of 1 g TiO2 nanofibre l(-1), pH 3, and UVC light irradiation, decolorization would be complete in two hours. A significant decrease in the COD values was observed, which clearly indicates that the photocatalytic method offers good potential for the removal of RB19 from aqueous solution. The kinetic of photocatalytic removal of RB19 followed the Langmuir-Hinshelwood model. These results suggest that TiO2 nanofibres with UV photocatalysis can be envisaged as a method for the treatment of coloured wastewaters, in particular in textile industries.