Laser pyrolysis fabrication of ferromagnetic gamma(')-Fe4N and FeC nanoparticles

Using the laser pyrolysis method, single phase gamma'-Fe4N nanoparticles we re prepared by a two step method involving preparation of nanoscale iron ox ide and a subsequent gas-solid nitridation reaction. Single phase Fe3C and Fe7C3 could be prepared by laser pyrolysis from Fe(CO)(5) and 3C(2)H(4) dir ectly. Characterization techniques such as XRD, TEM and vibrating sample ma gnetometer were used to measure phase structure, particle size and magnetic properties of these nanoscale nitride and carbide particles. (C) 2000 Amer ican Institute of Physics. [S0021-8979(00)38408-0].