Preparation and characterization of mixed iron–titanium oxide nanostructure

The Fe₂O₃–TiO₂ mixed nanostructure was grown from Fe/Ti metallic source using evaporation–condensation method. The formation of mixed Fe₂O₃–TiO₂ nanostructures was confirmed by energy dispersive analysis of X-ray and X-ray diffraction analysis. The scanning electron microscopy showed that the samples consisted of large amounts of two kinds dispersed particulates. The small particulates had sizes in the range of 130–170 nm and the big particulates had sizes in the range of 300–800 nm. Optical properties including refractive index (n), extinction coefficient (k), energy band gap (E_g), and Urbach energy (E_u) of the mixed thin film were investigated by spectroscopic ellipsometer. The Fe₂O₃–TiO₂ nanostructure had low n values compared to the previously reported values for Fe₂O₃ and TiO₂, while the value of band gap (2.54 ± 0.02 eV) lied in between the band gap values of Fe₂O₃ and TiO₂. The mixed Fe₂O₃–TiO₂ nanostructures showed enhanced photocatalytic activities.