Heterogeneous photocatalysis, which is one of the advanced oxidation processes, could be an alternative method for wastewater treatment. This technique requires the presence of a photocatalyst, typically a semiconductor, which can be excited by the irradiation with a light of a proper wavelength. This could initiate the mineralization of the organic pollutant via multiple steps or possible intermediates.
During the Ph.D. dissertation my main goal was to investigate TiO2 based composites. The bottom line was to broaden the applicability spectrum of titania by forming composites with different materials, such as with noble metal nanoparticles, copper nanoparticles or with lanthanide doped NaYF4 in order to utilize upconverted light as well. In the first instance gold and platinum nanoparticles were deposited simultaneously on different commercial titanias, then copper nanoparticles were deposited on commercial titanias, then ternary composites were formed with Yb3+, Er3+ and Tm3+ doped NaYF4, gold nanoparticles and TiO2. My aim was to investigate the photocatalytic activity, through the degradation of different model pollutants and hydrogen production, beside the morphological and structural properties of the prepared materials.