Investigation of the Influence of Organometallic Precursors on the Formation of Cobalt Nanoparticles

An investigation of the influence of organometallic precursors on the formation of cobalt nanoparticles is presented. The cobalt nanoparticles were obtained by decomposing two different organometallic cobalt complexes, [(Co2(μ-HC⋮CH)(CO)6] and [Co2(CO)8], under identical experimental conditions. Time-dependent FT-IR analysis revealed different decomposition routes, rates, and reaction intermediates leading to the formation of cobalt nanoparticles. Spectroscopic data in addition to X-ray crystallography confirmed the structures of reaction intermediates from [(Co2(μ-HC⋮CH)(CO)6]. The crystal structure, particle size, size distribution, and magnetic properties of the cobalt nanoparticles from the two precursors were analyzed using synchrotron radiation based X-ray absorption spectroscopy (XAS), transmission electron microscopy (TEM), and superconducting quantum interference device (SQUID) magnetometry, respectively, and showed significant differences.