Method for forming nickel plated graphene hollow sphere

A method for forming a nickel plated graphene hollow sphere, comprising:

• step (1):
• after removing an oxide layer from a surface of a non-powdered metal medium, whose standard electrode potential is lower than that of nickel, by sanding the surface using a sandpaper, immersing the metal medium in an inorganic acid solution to conduct an acid treatment for at least 3 minutes starting from continuous generation of bubbles on the surface of the metal medium, and then washing and drying the metal medium so as to give an acid treated metal medium;
• and
• step (2):
• uniformly dispersing graphene in an electroless plating solution at a concentration of 0.08 to 0.15 g/L, immersing the acid treated metal medium in the electroless plating solution containing dispersed graphene, and when the temperature of the electroless plating solution containing dispersed graphene has reached 60 to 80° C., adding a reducing agent into the electroless plating solution containing dispersed graphene;
• conducting a reaction for at least 90 minutes at a stirring speed of 120 to 180 rpm;
• then removing the acid treated metal medium that was unreacted after the reaction, and collecting a powder resulting from the reaction;
• and washing and drying the collected powder to obtain a nickel plated graphene hollow sphere;
• wherein, the metal medium is iron or aluminum;
• and
• wherein, the electroless plating solution consists of a soluble nickel salt, a citrate salt, a pH adjusting agent, and water with a nickel ion concentration of 0.03 to 0.06 mol/L and a citrate ion concentration of 0.02 to 0.04 mol/L, and has a pH of 10 to 13;
• wherein, the pH adjusting agent is sodium hydroxide;
• and wherein, the reducing agent is hydrazine hydrate, sodium hypophosphite, or sodium borohydride.