Efficient preparation for Ni nanopowders by anodic arc plasma

Sphere-shape nickel nanopowders were successfully prepared at high rate (up to 1.3 g/min) by anodic arc discharge plasma method. The morphology, crystalline structure, particle size and specific surface area of the samples were characterized via X-ray diffraction (XRD), transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED), and Brunauer–Emmett–Teller (BET) surface area analysis. The influences of the technology parameters on the yield rate and particle size of Ni nanopowders were studied, and the referential process parameters were obtained. The experimental results indicate that the crystal structure of the samples is FCC structure as same as that of the bulk materials. The specific surface area is 14.23 m2/g, with the particle size distribution ranging from 20 to 70 nm, the average particle size about 47 nm obtained from TEM and confirmed from XRD and BET results. This technique is a convenient and effective method to prepare high quality nanopowders with uniform size, higher purity, narrow size distribution and spherical shape. The yield rate and particle size increase with the increase of the arc current or gas pressure when other factors are fixed.