Synthesis of MgAC-Fe3O4/TiO2 hybrid nanocomposites via sol-gel chemistry for water treatment by photo-Fenton and photocatalytic reactions.

MgAC-Fe3O4/TiO2 hybrid nanocomposites were synthesized in different ratios of MgAC-Fe3O4 and TiO2 precursor. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray fluorescence spectrometry (XRF), electron spin resonance spectrometry (ESR), Brunauer-Emmett-Teller (BET), photoluminescence (PL), and UV photoelectron spectroscopy (UPS) were used to characterize the nanocomposites. The increase of MgAC-Fe3O4, in the hybrid nanocomposites' core-shell structure, led to the decrease of anatase TiO2 peaks, thus reducing the photo-Fenton and photocatalytic activities. According to the obtained data, MgAC-Fe3O4 [0.05 g]/TiO2 showed the best photo-Fenton and photocatalytic activities, having removed ~93% of MB (photo-Fenton reaction) and ~80% of phenol (photocatalytic reaction) after 20 and 80 mins, respectively. On the pilot scale (30 L), MgAC-Fe3O4 [0.05 g]/TiO2 was completely removed after 27 and 30 hours by the photo-Fenton and photocatalytic activities, respectively. The synergistic effect gained from the combined photo-Fenton and photocatalytic activities of Fe3O4 and TiO2, respectively, was credited for the performances of the MgAC-Fe3O4/TiO2 hybrid nanocomposites.