Synthesis and characterisation of iron doped boehmite nanofibres, nanotubes and nanosheets

The modification of nanostructured materials is of great interest due to controllable and unusual properties inherent in such materials. In this paper, iron doped boehmite nanofibres, nanotubes and nanosheets with varying iron content have been prepared through low temperature hydrothermal treatment in the presence of poly (ethylene oxide) surfactant. The combination of transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX) and N₂ adsorption were employed to characterize the resulting nanostructures. TEM images showed that the resulting nanostructures are predominantly nanofibres when iron content is less than 5 % (mol/mol); in contrast nanosheets were formed when iron doping was above 5%. Nanotubes instead of nanofibres and iron rich particles were observed in samples with 20 % added iron. XRD showed that the iron doped nanostructures are boehmite (gamma-AlOOH), with EDX analysis indicating the maximum iron content in the boehmite nanostructures is about 4.3%. Nitrogen adsorption results indicate a lowering of the surface area for the iron doped phase in comparison to that of undoped boehmite nanofibres. Further study is required to determine the magnetic and optical properties of the iron doped boehmite nanostructures for their prospective applications. A detailed characterization of the iron doped nanofibres is presented.