Synthesis of CoCrFeO₄ Nanoparticles Using Microemulsion Methods and Size-Dependent Studies of Their Magnetic Properties

Normal and reverse micelle microemulsion methods were used to synthesis single-phase CoCrFeO 4 nanoparticles with a controlled size range of 6−16 nm and a size distribution of 14%. The size-dependent magnetic properties were characterized and found to agree well with Stoner−Wohlfarth theory. The results from nanoparticles prepared by the normal micelle and reverse micelle microemulsion methods were consistent with each other. The CoCrFeO 4 nanoparticles did not display the types of anomalous magnetic properties reported for their bulk-phase material. Using CoCrFeO 4 nanoparticles as precursors for the formation of a bulk sample resulted in a material that displayed an unusual susceptibility behavior but not the anomalous temperature-dependent hysteresis trend usually observed in conventional CoCrFeO 4 bulk materials.