Whole powder pattern modeling of X-ray diffraction data, morphology, optical and magnetic properties of the Co/ NiO...

Nanomaterials of transition metal oxides such as NiO play an imperative role in the wide range of applications due to their electrically insulating, antiferromagnetic and optical properties. Therefore, preparation, characterization, and studying their application cause the development of scientific and industrial fields. This work presents a comprehensive investigation of the structural, optical, and magnetic properties of cobalt-doped nickel oxide (Ni_1-xCo_xO, 0.0 ≤ x ≤ 0.1) prepared by the electrospinning technique. The effect of Co doping concentration on the structural, optical, and magnetic properties of NiO nanofibers was investigated using scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), a UV-vis diffuse reflectance spectrophotometer (DRS), and a Vibrating Sample Magnetometer (VSM). The X-ray diffraction (XRD) combined with Rietveld refinement revealed the cubic NiO structure with a preferential orientation of (200) for all the samples. The average crystallite size was increased with increasing cobalt doping (Co) concentration. SEM results show that all possess fibrous net structures. The FTIR spectra showed a wide range of bands, indicating the existence of several linked functional groups and stretching vibration corresponding to the Ni-O bond. DRS spectra indicate that the optical band gaps were in the range 4.42-4.08 eV, depending on the Co concentration. Additionally, the VSM results show a significant improvement in the ferromagnetic behavior of the sample upon an increase in doping concentration.