Synthesis of hierarchical Fe2O3/SnO2 hollow heterostructures and their improved photocatalytic properties

In the present study, hierarchical α-Fe2O3/SnO2 hollow heterostructures were successfully synthesized by a template growth method. The crystal structure, morphology, composition and surface area of obtained heterostructures were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and BET surface area analysis. The results reveal that [001]-directed SnO2 nanorods grow on the side surface of the [001]-directed α-Fe2O3 hollow nanotubes/nanorings, forming image and image interfaces. These heterostructures can be further converted into magnetic γ-Fe2O3/SnO2 heterostructure without any significant change in morphology. These α-Fe2O3/SnO2 hollow heterostructures exhibit much higher photocatalytic activities for degradation of methylene blue in comparison with that of pure α-Fe2O3 nanotubes/nanorings in the wide spectral region from UV to visible due to both larger surface area and improved electron–hole separation efficiency in the interface of heterostructure.