Synthesis of cobalt ferrite nanoparticles by ultrasonic wave-assisted technology

Powders of finely dispersed cobalt ferrite were obtained by sonication. With the help of X-ray analysis, scanning electron microscopy, the influence of the initial pH of the solution and the processing conditions on the properties of the compounds formed was investigated. Samples were obtained from precursors having different pH values ranging from 7.0 to 12.0. It has been established that at pH 7-10, cobalt ferrite is formed by the mechanism of incorporation of cobalt cations into the crystal lattice of maghemite. At pH = 10 is magnetite. Single-phase cobalt ferrite is formed at pH = 12. The dependence of the coercive force and the saturation magnetization on the initial pH is established. The maximum values of the coercive force 460.3 Oe and the saturation magnetization 61.3 emu / g correspond to a pH of 12. An increase in the particle size during sonication has been established. The size of the agglomerates is 1-10 μm according to the electron microscopy data. The particle sizes calculated using the - Scherrer formula were 35-70 nm.