High-yield synthesis of dendritic Ni nanostructures by hydrothermal reduction

Uniform Ni dendritic nanostructures were prepared via a facile hydrothermal reduction approach in the presence of surfactants with a high yield of 98%. The morphology and structure of the products are characterized by scanning electronic microscopy (SEM), energy dispersive X-ray (EDX), transmission electronic microscopy (TEM), electron diffraction (ED) and X-ray diffraction (XRD) techniques. The assembled nanostructures were composed of ordered nanoscale fractal structure with the length of the dendrite trunks of 0.5–2 μm, and the thickness of the dendrites of 10–30 nm, as characterized by SEM and TEM. The parameters that were essential for the special dendrite formation were studied by varying the hydrothermal temperature, the concentration of NaOH and the initial Ni2+ ions or CTAB, keeping other conditions unchanged. These materials exhibited ferromagnetic characteristics with an enhanced magnetic coercivity in comparison with the bulk nickel crystals and hollow Ni nanometer-sized spheres, which is attributed to their peculiar morphology.