Fe2O3/TiO2 Tube-like Nanostructures: Synthesis, Structural Transformation and the Enhanced Sensing Properties

The paper describes for the first time the successful synthesis of Fe2O3/TiO2 tube like nanostructures, or which TiO2 shell is of quasi-single crystalline characteristic and its thickness can be controlled through adjusting the added amount of aqueous Ti(SO4)(2) solution. The characterization of samples obtained at different stages using transmission electron microscope indicates that the outer TiO2 shell is changed gradually from amorphous and polycrystalline phase into quasi-single crystal under thermal actions through the Ostwald ripening process, accompanying the corrosion of the central parts of Fe2O3 nanorods, and the formation of small particles separating each other, leading to the special core/shell nanorods. Furthermore, Fe2O3/TiO2 tubelike nanostructures can be transformed into Fe2TiO5 nanostructures after they are thermally treated at higher temperatures. Those nanostructures exhibit enhanced ethanol sensing properties with respect to the monocomponent. Our results imply that, not only hollow nanostructures, but also a novel type of nanostructures can be fabricated by the present method for nanodevices.