Low-Temperature Nitridation of Fe Nanoparticles Precursor

Nitridation of Fe nanoparticle precursor was performed in a NH₃ atmosphere at the temperatures of 473 K and 673 K for one hour. Fe nanoparticles precursor had a typical spherical shape with iron oxides shell and α-Fe core, which was obtained by an arc-discharge method. Up to date, the nitriding temperature of 473 K in present work was the lowest by thermal ammonolysis method because of the characteristics of the nano-sized particles. The resultant product after nitridation was a mixture of iron-nitrides (γ′-Fe₄N and ε-Fe₃N) nanoparticles with homogeneous dispersion. The nitriding mechanism, oxidizing behaviors and magnetic properties of iron-nitride nanoparticles were measured and discussed.