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α-Fe 2 O 3 was synthesized by preparing a mixture of Fe(III) nitrate with urea as a precursor. The yellowish coloured precursor was calcined at 400 • C for 2 h, resulting in the formation of bright red coloured hematite. The surface properties and catalytic activity were compared with a reference sample prepared without the use of urea. It was observed that urea-induced synthesis resulted in a sample having nanosize and large lattice strain, accompanied by the development of ferromagnetic behaviour. The catalytic activity was evaluated for the decomposition of H 2 O 2 through the photo-Fenton process in sunlight. The urea-synthesized sample showed an usually large photo-Fenton effect and the catalyst could be easily recovered and reused due to its ferromagnetic behaviour.

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In the present investigation we report presence of N, S and Ti3+ in the TiO2 samples and surface exhibits acidic characteristics. Synthesized TiO2 samples were also found to be ferromagnetic in nature at room temperature and shows high photocatalytic activity in comparison to commercially available TiO2 (DP-25). Nanosize TiO2 with high surface area was obtained by simple sol – gel method of synthesis and during the synthesis hydrazine sulphate was used as fuel. Synthesized TiO2 was found to be with N and S doping and also surface defects were present due to cationic and anionic vacancies. The presence of defects were confirmed from the Raman, IR, SEM-EDAX, PL analysis. Presence of Ti3+ in the TiO2 samples was confirmed from the ESR and XPS Spectra. XPS also showed presence of nitrogen and sulphur doping in the TiO2 samples. Synthesized TiO2 possesses acidic surface and surface acidity was measured from the pyridine adsorption and NH3-TPD studies. Ferromagnetic behavior of the synthesized samples was confirmed from the VSM measurements. Synthesized samples were further studied for their photocatalytic activity towards methylene blue dye and 4-nitrophenol degradation and for photo-oxidation benmezene to phenol conversion.

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