Synthesis of metal-carbon nanoparticles in pulsed UV-photolysis of Fe(CO)$_5$–CCl$_4$ mixtures at room temperature

Synthesis of iron-carbon nanoparticles in joint photolysis of iron pentacarbonyl (Fe(CO)$_5$) and carbon tetrachloride (CCl$_4$) has been studied. When mixtures containing iron pentacarbonyl and CCl$_4$ are exposed to UV light, Fe(CO)$_5$ molecules decompose to yield an atomic vapor of iron with well-known and easily controlled parameters, whereas CCl$_4$ molecules decompose to give CCl$_3$ radicals. A pulsed Nd:YAG laser (fourth harmonic, 266 nm) served as a source of light. The growth process of nanoparticles in condensation of supersaturated vapors was monitored by the laser extinction method; nanoparticle samples were examined with an atomic-force microscope. It was found that the concentration of the CCl$_4$ additive affects the manner in which the optical properties of nanoparticles synthesized in a binary mixture change relative to the properties of nanoparticles synthesized in photolysis of pure Fe(CO)$_5$, which indicates that a carbon shell grows on the surface of iron nanoparticles.