Structural, morphology, optical, and magnetic study of room-temperature ferromagnetic α-Fe2O3 nanofibers

In this study, the electrospinning technique was successfully used to fabricate α-Fe2O3 nanofibers. Fe(NO3)3-9H2O, polyvinyl pyrrolidone (PVP), and N,N-dimethylformamide (DMF) were used as sol for spinning nanofibers, and the final product was calcined at three different calcination temperatures 500 °C, 600 °C, and 700 °C. Nanofiber samples were characterized by X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR), scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS), and vibrating sample magnetometer (VSM) techniques. In view of the structural and chemical properties, XRD and FT-IR confirmed the formation of well-crystalline α-Fe2O3 nanofibers without any phase transition after thermal treatment. X-ray diffraction patterns shows single rhombohedral phase of the α-Fe2O3 fibers. It is evident from the Rietveld refinement of X-ray diffraction data that calcination temperatures have influenced on the microstructural parameters of nanofibers. SEM observations revealed the formation of smooth, granule, and beaded free fibers after calcination of as-spun fibers. DRS measurement indicates different electronic transition in the wavelength interval 270–750 nm. VSM analysis shows ferromagnetic behavior of the prepared fibers.