Optimization of Conditions for Obtaining Stable Hydrosols of Magnetite Nanoparticles

The work is devoted to the study of the influence of reaction parameters on the qualitative and quantitative composition of magnetite nanoparticles. The method of their synthesis is optimized using the method of mathematical planning and processing of experimental data. The mathematical model is obtained. It was established that the molar ratio of iron (II) and (III) ions, the time of preliminary boiling of distilled water for preparing solutions, the presence of an inert atmosphere of nitrogen, as well as an excess of alkali affect the formation of a stoichiometric product. Monophase magnetite nanoparticles with an average diameter of 8-12 nm were obtained under optimal conditions. The product is characterized by the methods of transmission electron microscopy and X-ray phase analysis. The effect of pretreatment of magnetite nanoparticles with solutions of strong mineral acids on the stability of its hydrosols has been studied by dynamic and electrophoretic light scattering. It was established that the best stabilization is achieved by pretreatment of magnetite with a solution of perchloric acid