Cobalt powder was prepared by hydrazine hydrate reducing cobalt salt method at room temperature by using ethanol,ethylene glycol and glycerin as the solvent of cobalt ion,respectively.The influence of cobalt ion solvent on the particle morphology of cobalt powder and its mechanism were investigated.The results showed that,the prepared cobalt powder consists of FCC and HCP crystalline phase.Using ethanol as cobalt ion solvent,the dendritic primary particles can be gained when the concentration of Co2+ion is too low (0.045 mol/L),and the near-spherical primary particles of cobalt powder can be gained when the rest of concentration of Co2+ion is used.When ethylene glycol or glycerin is used as cobalt ion solvent,smooth spherical primary particles can be obtained because of the effect of micro reactor formed by polyhydric alcohols.The way of the ethanol content influencing the morphology is by means of affecting the nucleation,growth and diffusion of the formed crystal nucleus.However,the way of the polyhydric alcohol content influencing the morphology is by means of affecting the viscosity of solution,as well as the integrity and the quantity of micro reactors.In the investigation,when the addition of ethylene glycol is 80 mL,the uniform and smooth spherical cobalt powders can be obtained.
