Structural and magnetic properties of aluminium substituted Ni-Cu spinel ferrite

Nickel-Copper spinel ferrite nanoparticles (NPs) with NiCuAlFeO with varying amounts of Aluminium (x = 0, 0.04,0.08,0.12) were synthesized using the microwave aided sol-gel method. The samples were analyzed using X-ray diffraction (XRD) to determine their structure. It was discovered that all the samples exhibited a cubic spinel structure and belonged to the Fd-3m space group. The crystallite size was found to be decreased from 45.21 nm to 37.34 nm with Al substitution. The TEM micrograph exhibits a nearly spherical morphology, with an average particle size of around 24.88 - 31.82 nm. The smooth M-H curve indicates the soft magnetic nature of prepared nanoparticles (NPs). The observed saturation magnetization (Ms) and coercivity (Hc) were found to initially increase until x=0.04, decreasing from 30.009 emu/g to 26.951 emu/g and 177.76 Oe to 164.20 Oe, respectively. This decrease is because of the decrease in nanocrystalline size and the distribution of cations in the spinel.