Enhanced magnetic properties of Co_0.5Cu_0.25Zn_0.25Fe_2-xCr_xO₄ nano ferrites

In this study, Co–Cu–Zn–Cr nano ferrites with a composition of Co_0.5Cu_0.25Zn_0.25Fe_2-xCr_xO₄ (x = 0.0, 0.05, 0.1, 0.15, 0.2, and 0.25) are prepared by sol–gel auto combustion method. These doped nanocrystalline ferrites’ characteristics were examined using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and vibratory sample magnetometer (VSM). Such analytical characterizations were done for the structural and magnetic investigations. The crystallographic structure was identified using X-ray diffraction, which showed that a single-phase cubic spinel structure has been formed. According to the Debye–Scherrer equation, the synthesized samples’ average crystallite diameters ranged from 55.32 to 33.41 nm. Field emission scanning electron microscopy (FE-SEM) was used to study the surface morphology of the particles, revealing aggregated grains with a sponge-like structure. Functional groups were detected using Fourier transform infrared (FTIR) spectroscopy; peaks at about 393.21–582.71 cm⁻¹ and 392.74–381.50 cm⁻¹ indicated specific chemical properties. Magnetic characteristics at room temperature were investigated using a vibrating sample magnetometer (VSM), revealing some magnetic parameters. Hysteresis curves demonstrate reduced coercivity (263.98 to 126.62 Oe) and saturation magnetization (43.72 to 63.29 emu/g) upon metal ion replacement in the Co–Cu–Zn nano ferrites.