Monodisperse Metallic Iron Nanoparticles Synthesized from Noncarbonyl Complex

Highly monodisperse, metallic iron nanoparticles were prepared by the alcohol reduction of a nontoxic metal precursor (Fe(III) acetylacetonate) in an organic solvent at elevated temperatures. In order to obtain a metallic iron phase and minimize iron oxide ones, a relatively high molar ratio of the reducing agent to the precursor is required. Compared with a single-step reaction, a two-step seed-mediated synthesis results in the systematic control of particle diameter while maintaining monodispersity. The standard deviation of particle diameter is less than 10%, which is sufficiently small to lead to ordered self-assemblies.