On the magnetic properties of nanosized CoFe2O4

Abstract Thermomagnetic properties of fine CoFeO 4 particles with average sizes of 43, 51, 66, 195 and 465 A were investigated between 5 and 800 K in fields up to 140 kOe. The particles with sizes of 43 and 51 A behave superparamagnetically at room temperature, but the others exhibit mixed superparamagnetic and ferrimagnetic behavior. The concentration of the ferrimagnetic phases and their magnetic properties were evaluated.