Shape-controlled synthesis of Ni particles via polyol reduction

Metallic Ni powders with different morphologies including icosahedra, microspheres, and flowerlike clusters composed of nanoflakes were successfully fabricated via polyol process. Alkalinity played the key role in the formation of these novel structures. The as-prepared products were characterized by X-ray diffractometry (XRD), field scanning electron microscopy (FESEM), transmission electron microscope (TEM), and selected area electron diffraction (SAED). A layer-by-layer growing process was demonstrated based on the experimental results. Magnetism investigation revealed that icosahedra and clusters exhibited much enhanced coercivity.