Heterogeneous
photocatalysis is one of the advanced oxidation processes (AOP’s). These are
very used nowadays for their implementation in tertiary water treatment with
solar activation, with very good results. In this study, TiO2 porous
films were synthesized by sol-gel method. Polyethylene glycol (PEG) 4000 was
used as a templating reagent, which is oxidized at a lower temperature than TiO2.
This allows the formation of a “skeleton” of porous TiO2 with
increased surface area, resulting in higher photocatalytic activity. The film
characterization was made with help of FE-SEM microscope, XRD diffractometer
and scotch tape test. Finally, the oxidation experiments were performed using
methylene blue as a model pollutant and they revealed an increase in the
photocatalytic activity of porous films in comparison with the non-porous
films.
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