Rietveld refinement, morphology analysis, optical and magnetic properties of magnesium-zinc ferrite nanofibers

•The electrospinning was used successfully to fabricate magnesium ferrite fibers.•Microstructure analysis of fibers was presented employing Rietveld method.•The optical properties were studied using UV–Vis diffuses reflectance spectra.•Ferrite fibers show higher value of saturation magnetization than nanoparticles. The magnesium-zinc ferrite (Mg1−xZnxFe2O4) nanofibers (with x = 0, 0.05, 0.10, and 0.15) were successfully prepared by the electrospinning technique followed by calcinations at temperature 550 °C. The structural, morphological, optical properties and magnetic characterization of the prepared nanofibers were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier Transform Infrared (FTIR), DRS and VSM. The XRD pattern has been analyzed employing Rietveld technique and revealed the diffraction peaks are mainly assigned to the cubic structure of the MgFe2O4 phase. The SEM images exhibit fabrication of the smooth and free of beads nanofibers with average diameter ranged from 180 ± 20 to 100 ± 20 nm. The absorption spectra and optical band gap were estimated by diffuse reflectance spectroscopy (DRS). DRS study showed an increase in the band gap energy of MgFe2O4 nanofibers upon increase in doping concentration. Magnetic properties of the pure MgFe2O4 and 10% Zn-doped MgFe2O4 nanofibers were characterized by using VSM magnetometer. Magnetic results showed saturation magnetism and eminence decrease with Zn doping.