Bulk synthesis of monodisperse Fe nanoparticles by electromagnetic levitational gas condensation method

A one-step bulk synthesis method for monodisperse Fe nanoparticles was developed by electromagnetic levitational gas condensation (ELGC) process. The Fe vapours ascending from the high temperature levitated droplet was condensed by cryogenic He-Ar gas mixture under atmospheric pressure. The spherical Fe nanoparticles with particle size of 72.1 +/- 19.5 nm and a narrow size distribution were prepared using the He-20%Ar gas mixture with the flow rate of 20 l/min. The production rate of the one-step ELGC process was estimated as high as 10 g/h. The nanoparticles were passivated by the formation of a thin layer of Fe oxides with the thickness of 3 nm. (C) 2008 Elsevier B.V. All rights reserved.