▎ 摘　　要

NOVELTY - A composite material comprises a graphene material, and carbon-containing ferromagnetic nanometer metal particles uniformly coated on the surface of the graphene material. The graphene material comprises a single graphite layer that is less than 50 nm thick. The metal particle has a diameter of 2-100 nm. The ferromagnetic metal is iron, cobalt, and/or nickel. The mass ratio of the metal to the carbon is 1-20:1. USE - A composite material used as a magnetic separation catalyst in wastewater treatment, electromagnetic shielding, and wave absorption. ADVANTAGE - The composite material has excellent magnetic performance and good conductivity. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparing the composite material, comprising: (A) ultrasonically dispersing 0.1-10 mg/mL graphite oxide solution for 0.5-5 hours to obtain a graphene oxide dispersing agent; (B) adding 0.1-5 mol/L ferromagnetic metal salt solution, where the mass ratio of the soluble salt of the ferromagnetic metal to the graphite oxide is 0.1-100:1; (C) mixing for 0.5-10 hours; (D) preparing 0.1-5 mol/L solution by using a precipitant with the molar ratio to the soluble salt of the transitional metal of 1-20:1; (E) adding the solution into the graphite oxide dispersing agent at 10 mL/minute; (F) drastically mixing, and reacting at 0-100 degrees C for 0.5-10 hours; (G) filtering, completely washing, and drying the material to obtain a composite powdery body; (H) heating the powdery body to 500-800 degrees C at 5-50 degrees C/minute at nitrogen or argon atmosphere; (I) inflating the mixed gas at 10-100 mL/minute for chemical vapor deposition for 1-60 minutes; and (J) cooling the reactants at nitrogen or argon atmosphere to room temperature.