Study on the structure and magnetic transformation of magnesium substituted cobalt spinel-type ferrite

In this paper, magnesium substitute cobalt ferrite with chemical formula Co 1− x Mg x Fe 2 O 4 ( x = 0.0, 0.25, 0.5, 0.75, 1.0) was prepared by sol–gel method. The prepared ferrite powder was characterized in a series of ways. X-ray diffraction (XRD) shows that the samples have a single-phase cubic spinel structure, and the structural parameters of the samples are different with the ion distribution. Fourier transform infrared spectroscopy (FTIR) can further verify the spinel structure of ferrite and analyze the elastic modulus of the prepared material. Beyond that, the completeness of chemical reactions can be determined by the information of functional groups. A scanning electron microscope (SEM) was used to monitor the morphology of the sample, which also showed that the samples were evenly distributed and agglomerated due to magnetic influence. Energy dispersive spectrometers (EDS) show that the elemental composition of the substance corresponds to a chemical formula and is free of other impurities. Vibrating sample magnetometer (VSM) shows that non-magnetic Mg 2+ can replace magnetic Co 2+ , which changes the interaction intensity and magnetic order between sites, thus changing the magnetic properties of samples, and realizing the magnetic transition from ferromagnetism to superparamagnetism.