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

Hollow hematite (alpha-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 degrees 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 alpha-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 alpha-Fe2O3 fibers have promising uses in important biological processes and biomedical applications.