Impact of cobalt doping on the properties of zinc ferrite (CoxZn1-xFe2O4)

The intercalation of Cobalt (Co) into Zinc (Zn) ferrite (Fe₂O₄₎ is a contemporary composite material with significant magnetic and structural characteristics. Our study investigates the Mössbauer, structural, and magnetic properties of Co-substituted ZnFe₂O₄, synthesized via microwave hydrothermal method. A series of polycrystalline samples were prepared by modulating the cobalt concentration (0.1, 0.4, 0.7, and 0.9) in zinc ferrite. We discovered a profound impact on lattice parameters and magnetization. Scanning electron microscopy (SEM) shows a uniform surface morphology with an accumulation of particles, including particle clustering. The X-ray diffraction (XRD) data confirm the single-phase cubic spinal structure. No additional impurities or subordinate phases were detected. UV-visible spectra show a slight shift in Co-doped ZnFe₂O₄ samples (2.60eV to 2.30eV) in optical bandgap with the increment of cobalt due to generating extra energy state. Fourier transform infrared (FTIR) spectroscopy is used to identiy functional group bending modes at specific wavelengths. Mössbauer spectroscopy analysis confirms the presence of cations that selectively inhabit a particular site of lattice, indicative of the preferential distribution of these ions within the crystal structure. Incorporating cobalt ions through doping significantly affects the material behavior, leading to changes in magnetic susceptibility, optical absorption spectra, and electrical conductivity.