Enhanced Fe-TiO 2 Solar Photocatalysts on Porous Platforms for Water Purification.

In this study, polyethylene glycol-modified titanium dioxide (PEG-modified TiO 2 ) nanopowders were prepared using a fast solvothermal method under microwave irradiation, and without any further calcination processes. These nanopowders were further impregnated on porous polymeric platforms by drop-casting. The effect of adding iron with different molar ratios (1, 2, and 5%) of iron precursor was investigated. The characterization of the produced materials was carried out by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Optical characterization of all the materials was also carried out. SEM showed that pure TiO 2 and Fe-TiO 2 nanostructures presented similar nanosized and spherical particles, which uniformly covered the substrates. From XRD, pure TiO 2 anatase was obtained for all nanopowders produced, which was further confirmed by Raman spectroscopy on the impregnated substrates. XPS and UV-VIS absorption spectroscopy emission spectra revealed that the presence of Fe ions on the Fe-TiO 2 nanostructures led to the introduction of new intermediate energy levels, as well as defects that contributed to an enhancement in the photocatalytic performance. The photocatalytic results under solar radiation demonstrated increased photocatalytic activity in the presence of the 5% Fe-TiO 2 nanostructures (Rhodamine B degradation of 85% after 3.5 h, compared to 74% with pure TiO 2 for the same exposure time). The photodegradation rate of RhB dye with the Fe-TiO 2 substrate was 1.5-times faster than pure TiO 2 . Reusability tests were also performed. The approach developed in this work originated novel functionalized photocatalytic platforms, which were revealed to be promising for the removal of organic dyes from wastewater.