Synthesis of multiwall α-Fe2O3 hollow fibers via a centrifugal spinning technique.

Hollow hematite (α-Fe2O3) fine fibers with multiwall structure were synthesized by utilizing a centrifugal spinning technique. Aqueous solutions of polyvinyl pyrrolidone and iron (III) nitrate nonahydrate were prepared and spun into fibers. The precursor fibers were heat treated at 650 °C to form iron oxide fibers. Scanning electron micrographs revealed the formation of iron oxide hollow fibers with multiwall structure with average wall thickness of 55 ± 15 nm and outer fiber diameter of 852 ± 86 nm. The formation of α-Fe2O3 was confirmed by X-ray diffraction analysis and the phase identification was verified by XRD pattern and transmission electron microscopy analysis. These hollow structure α-Fe2O3 fibers have promising uses in important biological processes and biomedical applications.