Preparation of copper nanoparticles by chemical reduction method using potassium borohydride

High dispersive copper nanoparticles were prepared by chemical reduction method using potassium borohydride as reducing agent. The effects of reactant ratio, concentration of CuSO4, reaction temperature, and dispersant on the size of product and conversion rate were studied. The morphologies of copper nanoparticles were characterized by scanning electron microscopy. The results show that the optimum process conditions are as follows: the molar ratio of KBH4 to CuSO4 is 0.75 (3:4), concentration of CuSO4 is 0.4 mol/L, reaction temperature is 30 °C, and dispersant is n-butyl alcohol. The average particles size of copper powders with spherical shape gained is about 100 nm.