Hematite doped magnetic TiO2 nanocomposites with improved photocatalytic activity

• The self-built electric field formed in the heterojunction of TiO2 and α-Fe2O3.
• The obtained composites exhibited better photocatalytic activity than P25.
• All the samples can be transferred easily by a magnet.

A facile approach for the fabrication of magnetic α-Fe2O3@TiO2 nanocomposites has been demonstrated. The obtained composites which were doped by proper amount of hematite exhibited better photocatalytic activity than the samples without α-Fe2O3 doping according to the photocatalytic degradation of methyl orange. Moreover, the photocatalytic degradation activity of these nanocomposites is better than P25 at the same photocatalytic experiment conditions. However, when the doping amount of hematite is high, the nanocomposites exhibit poor photocatalytic activity. Because of the self-built electric field formed in the heterojunction of α-Fe2O3 and TiO2, it can be confirmed that of the doping hematite makes a contribution to the ultraviolet–vis light absorption and provides more electrons for the catalysis process. And the combination of two kinds of semiconductor is the key to improve the utilization efficiency of light. Furthermore, that all the samples can be transferred easily by a magnet shows potential application for wastewater treatment.

(a) Schematic illustration for the formation mechanism of samples A–C. (b) The photocatalytic degradation rate curves of sample A and sample D.Figure optionsDownload as PowerPoint slide