Interplay between cation distribution and magnetic properties for CoAlxFe2−xO4 0.0 ≤ x ≤ 0.7 nanoparticles

The relationship between cationic distribution, bond angle, bond length with magnetic properties of CoFe2−xAlxO4 (0 ≤ x ≤ 1) nano-ferrite is demonstrated. The magnetic properties of spinel nano-ferrites have been examined using a vibrating sample magnetometer. The crystal structure was calculated using an X-ray diffractometer and ratified via high-resolution transmission electron microscopy. Substitution of Al content (x) in cobalt ferrite caused a reduction in particle size, lattice parameter, and magnetic properties. The saturation magnetization changes with increasing Al content due to the effect of cation distribution in tetrahedral and octahedral sites and due to a change in ferrimagnetic structure. The existence of the strong dipolar interactions and/or exchange coupling is established via the appearance of double peaks in switching field distribution. The obtained data ratify that the substitution of Al content in the cobalt system is a powerful tool for tuning the magnetic properties of the investigated samples. This substitution decreases the magnetic energy loss and the switching field distribution. Consequently, the studied samples are recommended to be used in transformer cores and high-density recording. The strong correlation between cation distribution, bond angle, bond length, and the magnetic properties of the studied samples is the main advantages of the present work as compared to the literature reported on Co-Al nano-ferrite.