A New Method for Preparation of Nanocrystalline Molybdenum Nitride

Nanocrystalline molybdenum nitride (γ-Mo₂N) with the cubic structure is prepared by the direct current arc discharge method in N₂ gas, using metal Mo or W rod as a cathode. The x-ray diffraction (XRD) and transmission electron microscopy (TEM) are used to characterize the product. It is found that the conversion of Mo to γ-Mo₂N and affinity of Mo to N₂ are determined by the nitrogen pressure. Moreover, we compare the effect of Mo and W rod as a cathode for preparing γ-Mo₂N. The average size of γ-Mo₂N particles is about 5nm. The rapid quenching mechanism can be used to explain the formation of nanocrystalline γ-Mo₂N.