Gamma irradiated nanostructured NiFe2O4: Effect of γ-photon on morphological, structural, optical, and magnetic properties

This article highlights the preparation of NiFe2O4 nanoparticles by adopting a sol-gel auto-combustion route. The prime focus of this study is to investigate the impact of gamma-irradiation on the microstructural, morphological, functional, optical, and magnetic characteristics. The resulting NiFe2O4 products have been characterized employing numerous instrumental techniques such as Field Emission Scanning Electron Microscopy (FESEM), X-ray Diffraction (XRD), UV-visible spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), and Physical Properties Measurement System for a variety of gamma-ray doses (0, 25, and 100 kGy). FESEM micrographs illustrate the aggregation of ferrite nanoparticles in the pristine NiFe2O4 product having an average particle size of 168 nm, and the surface morphology is altered after exposure to gamma-irradiation. XRD spectra have been analyzed employing the Rietveld method, and the results of the XRD investigation reveal the desired phases (cubic spinel phases) of NiFe2O4 with the observation of other transitional phases. The values of the crystallite size are in the range of 34.04-34.71 nm investigated by the Debye-Scherrer (D-S) method. Several microstructural parameters, such as bond length, bond angle, and hopping length, have been determined from the analysis of the Rietveld method. This study reports that gamma-irradiations demonstrate a great influence on optical bandgap energy, and it varies from 1.80 to 1.89 eV evaluated via the Kubelka-Munk function. The FTIR measurement depicts a proof for the persistence of Ni-O and Fe-O stretching vibrations within the respective products at positions 365 and 547 cm(-1), respectively, thus indicating the successful development of NiFe2O4. The saturation magnetization (M-S) of the pristine Ni ferrite product is noticed to be 28.08 emu/g. A considerable increase in M-S is observed in the case of low gamma-dose (25 kGy), and a decrement nature is disclosed after the result of high dose of gamma-irradiation (100 kGy). (c) 2021 Author(s).