Surfactant effects on the shapes of cobalt nanoparticles

The effect of surfactant coatings on the shapes and sizes of cobalt nanoparticles has been investigated. Cobalt nanoparticles were synthesized by thermal decomposition of a cobalt containing precursor in the presence of various surfactants. At room temperature the cobalt nanoparticles have a beta-manganese structure also known as the epsilon-cobalt structure. The shapes of the cobalt nanoparticles include: spherical, triangular, rod-like, and hexagonal. The shapes of cobalt nanoparticles depend on the type of the surfactant used in the synthesis and the temperature at which the cobalt precursor was added to the reaction mixture. (c) 2006 Elsevier B.V. All rights reserved.