Synthesis of nickel powders from various aqueous media through chemical reduction method

Ultrafine nickel powders, spherical shape with submicron size, have been prepared at various reaction temperatures by the chemical reduction of the aqueous solution of nickel salt with hydrazine with various alcohol containing solvent. The effects of reaction temperature, the volume ratio of alcohol to alcohol containing solvent, and the kind of alcohol for the morphological control were systematically investigated. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmitted electron microscopy (TEM), thermal gravimetry (TG), BET method, and X-ray photoelectron spectroscopy (XPS) were employed to characterize the nickel powders prepared at various conditions. In this investigation, the average particle size of the samples decreased from 0.65 to 0.3 μm with increasing volume ratio of ethanol to ethanol-containing solvent. The nickel powders obtained from the ethanol-containing solvent were smaller and more uniform than those obtained from the 1-propanol and 1-butanol containing solvent. It was found that the volume ratio of alcohol and the kind of alcohol were strongly affected on the size and the uniformity of the nickel powders.