Preparation of nickel/graphite composite powder by electroless nickel plating

The nickel/graphite composite powder was prepared by electroless nickel plating. Laser-diffraction and SEM were employed to observe particle dimension and surface morphology of nickel/graphite composite powder. The effects of main salt NiSO4, reducer N2H4 and activator PdCl2 on surface morphology of nickel/graphite composite powder were investigated. The growth mechanism of Ni deposits on graphite powder surface was also studied. Based on experimental results, some conclusions can be drawn as below: the deposition rate of electroless nickel plating is proper and nickel deposits is uniform when NiSO4 mass concentration is 20 g/L and N2H4 volume fraction is 2%. The crystal grain of nickel deposits is finer and homogeneous when PdCl2 mass concentration is 0.03 g/L and 0.1 g/L. The main growth period of nickel deposits is 90 min to 120 min from beginning. The nickel deposits grow firstly on activation center and cover whole surface of graphite particle as reaction proceeding.