Structural, magnetic, optical, and impedance properties of SrxCo1−xFe2O4 nanoparticles prepared by sol–gel method

Sr2+ ions-substituted cobalt ferrite having the composition formula SrxCo1−xFe2O4 (x = 0.05, 0.10, 0.15, and 0.20) was synthesized with sol–gel method. X-ray diffraction (XRD) patterns proved that the samples had a spinel structure. The Fourier-transform infrared (FTIR) spectra showed that the samples have two characteristic bands about the intrinsic vibrations of spinel ferrite. The morphology and chemical elements were tested by scanning electron microscope (SEM) and energy-dispersive spectrometer (EDS). The elemental state of annealed samples was examined by X-ray photoelectron spectroscopy (XPS). The magnetic data showed the coercivity increased from 954.33 Oe to 1545.54 Oe when the Sr2+ ions content increased. The optical absorption properties of annealed samples were investigated by UV–Vis spectroscopy. Complex impedance spectroscopy showed that grain resistance of Sr0.10Co0.90Fe2O4 sample was 443.9 Ω.