Solvothermal growth of NiS single-crystalline nanorods

Nanorods of NiS were successfully prepared by a solvothermal synthetic route using S and Ni powders as reagents in ethylenediamine (en) solvent at the temperature of 200 °C. The as prepared NiS nanorods were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). It was found that the nanorods have diameters and lengths in the region from 80 nm to 120 nm, and from 2 μm to 3 μm, respectively. The NiS nanorods are single crystals with millerite structure. On the basis of the experimental results and corresponding literatures, a possible growth mechanism of the NiS nanorods crystals is discussed.