Hydrothermal synthesis and characterization of nickel and cobalt sulfides nanocrystallines

Novel sea-urchinlike nanocrystallines of hexagonal α-NiS, rhombohedral β-NiS, and cubic phase Co9S8 have been successfully synthesized via a facile hydrothermal synthetic route from the thiourea and hydrated metal chloride in hydrazine hydrate solution under mild conditions. The morphology and structure of the final products were investigated in detail by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and selected area electron diffraction (SAED). TEM and SEM show the formation process of the metal sulfides, and the probable formation mechanism of the sea-urchinlike nickel and cobalt sulfides nanocrystallines was discussed on the basis of the experimental results.