Preparation and characterization of magnetic α-Fe2O3 nanofibers coated with uniform layers of silica

Magnetic composite fibers with α-Fe2O3/SiO2 core–shell structure were prepared by the electrospinning and sol–gel method. The α-Fe2O3 ceramic nanofibers were prepared by electrospinning of solution of poly (vinyl alcohol) (PVA) and Fe(NO3)3·9H2O composite nanofibers followed by calcinations. Controlled hydrolysis and condensation of tetraethyl orthosilicate (TEOS) caused a dense silica layer deposit on the surface of α-Fe2O3 nanofibers with a desired thickness using the sol–gel method (denoted as α-Fe2O3@SiO2). The products were characterized with scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive X-ray spectroscope (EDX), vibrating sample magnetometer (VSM), X-ray diffraction (XRD) and Fourier transform infrared (FT-IR). The α-Fe2O3@SiO2 core/shell fibers showed a high value of specific saturation magnetization.