Phase control and characterization of Fe and Fe-oxide nanocrystals synthesized by pulsed wire evaporation method

Pulsed wire evaporation (PWE) technique has been used to synthesize nanosize iron-metal and -oxide powders, where iron wire was evaporated and condensed by an intense pulsed current in various ambient gas conditions. The iron nanopowder was obtained by evaporating a thin iron wire in an argon gas, and as for the iron-oxide powers, a mixed gas of Ar/O 2 was used as an ambient gas. The phase analysis of the produced iron-oxide powders was systemically investigated using Mössbauer spectra, where the phase of Fe 2O 3 and Fe 3O 4 showed a strong dependence on the oxygen concentration in the mixed gas. The results suggest that classified nanosize iron-metal and -oxide powders can be obtained simply by controlling a well-designed ambient gas condition during the PWE process.