Magnetically separable γ-Fe2O3/TiO2 nanotubes for photodegradation of aqueous methyl orange

Magnetically separable γ-Fe2O3/TiO2 nanotubes catalyst was successfully prepared by the confined reaction of liquid Fe(CO)5 in/around TiO2 nanotubes. The hybrids were systematically characterized and showed strong absorptions in the visible region. Under simulated sunlight and the same experimental conditions, 91% of methyl orange (MO) can be degraded by the hybrids, whereas only 49%, 59% and 81% of the MO can be degraded in the presence of anatase TiO2 powder, commercial P25, and TiO2 nanotubes. Importantly, the γ-Fe2O3/TiO2 nanotubes catalyst can be recycled by external magnetic field for repeated use without obvious loss of its photocatalytic efficiency.