The role of terbium cation substitution on the magnetic properties of cobalt ferrite nanoparticles

► Fine particles single phase of CoFe2−xTbxO4 (x=0-0.5) were prepared by a reverse micelle method. ► With an increase in terbium amount, the coercive field decreases while the saturation of magnetization increases. ► Terbium cations were distributed in the tetrahedral and octahedral sites,however, their preference is in tetrahedral sites. ► The blocking temperature increases with an increase in terbium concentration in synthesized samples.