Abstract
Ferrimagnetic nanoparticles, which are compounds of iron oxide with other types of metal oxides, are one of the promising types of nanoparticles among a wide variety. Interest in this type of nanostructures is primarily due to the great prospects for their use in biomedical applications, targeted drug delivery, alongside hyperthermia and magnetic resonance therapy. The relevance of the research consists in obtaining new knowledge in the field of research of phase transformations in ferritic Fe 3 O 4 /ZnO nanoparticles under variation of synthesis conditions, alongside assessing their practical application in comparison with literature data, and determining the limits of applicability in hyperthermia. The key result of this study is to evaluate the effectiveness of using Fe 3 O 4 /ZnO nanoparticles, as well as determining the influence of thermal annealing conditions on the phase transformation processes in nanoparticles. According to X-ray phase analysis data, the dynamics of phase transformations in Fe 3 O 4 /ZnO nanoparticles contingent upon the thermal annealing temperature was established. These phase transformations can be written in the following form: Fe 3 O 4 /ZnO → Fe 2 O 3 /ZnO → Fe 2 O 3 /ZnFe 2 O 4 → ZnFe 2 O 4 /ZnO. During the studies, it was found that the formation of the ZnFe 2 O 4 phase leads not only to the heating rate growth, but also to the formation of a linear dependence of the change in the solution temperature on the time of exposure to an alternating magnetic field.