The structure and magnetic properties of cobalt ferrite nanoparticles synthesized in a system of direct micelles of amphiphiles by means of ion flotoextraction

A method for obtaining nanoparticles in a system of direct micelles of amphiphiles using ion flotoextraction for concentrating ions from diluted water solutions is developed. Nanoparticles of the composition CoFe2O4 with a structure close to spinel are obtained. It is established that the particles consist of two components: well-formed phases of cobalt ferrite CoFe2O4 and its amorphous analog. It is shown that the nanoparticles have a maximum size distribution ranging from 4 to 6 nm; on a carbon substrate, they self-organize into a periodic colloidal structure. It is concluded that nanosized CoFe2O4 powder has a blocking temperature of about 45 K, a magnetic moment of about 0.85–0.9μB at a temperature of 0 K, and the Neöl temperature lies in the range of 110 to 250 K.