Co-evaporation of transition metal salt and SiO powder toward copper(or nickel)/silicon-contained composite nanostructures

We demonstrate that several novel copper(or nickel)/silicon-contained composite nanostructures were successfully synthesized by co-evaporating SiO powder and corresponding transition metal salts (transition metal organic salt and transition metal inorganic salt), including nickel formate, cobalt acetate, and copper sulfate. The morphologies, compositions, and crystal structures of products were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). The results indicate that the morphology and composition of formed copper(or nickel)/silicon-contained composite nanostructures are dramatically influenced by the distance between SiO powder and transition metal salts, or by the pre-sintering temperature of the reactants. The possible formation mechanisms of these composite nanostructures were discussed on the basis of experimental observations.