Effects of process parameters on synthesis of Zn ultrafine/nanoparticles by electromagnetic levitational gas condensation

Zn ultrafine/nanoparticles with different morphologies were produced using the one-step, relatively large-scale synthesis method of electromagnetic levitational gas condensation. The Zn vapors ascending from the high temperature levitated Zn droplet were condensed by Ar and He-20%Ar gas mixtures under atmospheric and reduced pressures. Effects of type, flow rate, temperature and pressure of the condensing gas on the size, size distribution and morphology of Zn particles were investigated. The particles were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), dynamic light scattering (DLS) and image analysis. A mechanism was also proposed for describing morphology change during the process. The process parameters for synthesis of the crystalline Zn ultrafine and nanoparticles were determined.