Synthesis of Fe-Doped TiO₂/α-Fe₂O₃core-shell nanowires using co-electrospinning and their magnetic property

We synthesized Fe-doped TiO₂/α-Fe₂O₃ core-shell nanowires(NWs) by means of a co-electrospinning method and demonstrated their magnetic properties. To investigate the structural, morphological, chemical, and magnetic properties of the samples, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy were used, as was a vibrating sample magnetometer. The morphology of the nanostructures obtained after calcination at 500°C exhibited core/shell NWs consisting of TiO₂ in the core region and α-Fe₂O₃ in the shell region. In addition, the XPS results confirmed the formation of Fe-doped TiO₂ by the doping effect of Fe³⁺ ions into the TiO₂ lattice, which can affect the ferromagnetic properties in the core region. For comparison, pure α-Fe₂O₃ NWs were also fabricated using an electrospinning method. With regard to the magnetic properties, the Fe-doped TiO₂/α-Fe₂O₃ core-shell NWs exhibited improved saturation magnetization(Ms) of approximately ~2.96 emu/g, which is approximately 6.1 times larger than that of pure α-Fe₂O₃ NWs. The performance enhancement can be explained by three main mechanisms: the doping effect of Fe ions into the TiO₂ lattice, the size effect of the Fe₂O₃ nanoparticles, and the structural effect of the core-shell nanostructures.