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.

Gold-Coated Iron (Fe@Au) Nanoparticles: Synthesis, Characterization, and Magnetic Field-Induced Self-Assembly

“…Especially in recent years, the interests in nanometer-scale magnetic particles are growing based on their potential application as high-density magnetic storage media (2,3). However, as the particle size decreases, the reactivity of the particle increases and the magnetic properties are in#uenced more by surface e!ects (4) has been developed (5}7).…”

Spherulitic copper–copper oxide nanostructure-based highly sensitive nonenzymatic glucose sensor

“…The formation of reverse micelles by CTAB in oil-in-water systems has been welldocumented in the literature. 15,16 However, there are no reports on the growth of such spherulitic structures by reverse micelle method. The high resistance of the toluenein-water microemulsion is in agreement with previous findings for spherical inverse micelle formation.…”

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Design, Synthesis, and Mechanistic Evaluation of Iron-Based Catalysis for Synthesis Gas Conversion to Fuels and Chemicals

“…The objectives are to advance our understanding of the processes involved in deposition and stabilizing Co metal clusters and to use this knowledge to prepare catalysts with higher dispersion and oxidative and sintering stability. A black colloid appears when the reaction is completed [32]. Subsequently, 0.5 g of SiO 2 was added to the colloidal solution and stirred for 3 h. Acetone solution (Aldrich, 99 %) was used to induce flocculation and then filtered.…”