Temperature Dependence of Morphology and Magnetic Properties of Cobalt Nanoparticles Prepared by an Inverse Micelle Technique

Abstract

We have fabricated cobalt nanoparticles using sodium borohydride reduction of cobalt chloride in a didodecyldimethylammonium bromide (DDAB)/toluene inverse micelle solution. The particle morphology changed from single particles to clusters as we increased the reaction temperature. Intracluster dipole−dipole interaction increased the blocking temperature and reduced the effective magnetic moment per cluster.