▎ 摘　　要

NOVELTY - Preparing composite film, comprises (a) mixing graphene and metal nanoparticles with solvent and then dispersing to obtain mixed dispersion of graphene/metal nanoparticles, (b) extruding mixed dispersion of graphene/metal nanoparticles and then solidifying to obtain composite film, and (c) carrying out reduction process of obtained film using a reducing agent to dry. The metal nanoparticles are gold, silver, aluminum, copper, iron, zinc, chromium, nickel, cobalt, platinum, palladium, iridium, rhodium, ruthenium, titanium, vanadium, magnesium, indium, lanthanum, indium and/or antimony. USE - The method is useful for preparing a composite film (claimed), which is used in a different industrial field. ADVANTAGE - The method is capable of simply preparing the composite film with improved electrical conductivity and good chemical stability in a convenient manner. DETAILED DESCRIPTION - Preparing composite film, comprises (a) mixing 1 pts. wt. graphene and 0.01-2 pts. wt. metal nanoparticles with 5-150 pts. wt. solvent and then ultrasonically dispersing to obtain a mixed dispersion of graphene/metal nanoparticles, (b) extruding mixed dispersion of graphene/metal nanoparticles in an extrusion device at speed of 1-100 ml/hours and then solidifying to 10-80 degrees C to obtain solidifying liquid and then standing for 1-100 seconds to obtain graphene oxide/metal nanoparticle composite film, and (c) carrying out reduction process of the obtained composite film using a reducing agent and then washing and drying. The extrusion device has a cuboid structure. The metal nanoparticles are gold, silver, aluminum, copper, iron, zinc, chromium, nickel, cobalt, platinum, palladium, iridium, rhodium, ruthenium, titanium, vanadium, magnesium, indium, lanthanum, indium and/or antimony. The solvent is water, methyl alcohol, ethyl alcohol, N-methylpyrrolidone, acetone, dimethyl sulfoxide, pyridine, dioxane, N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran, butanone or diethylene glycol. The solidifying liquid is 5-10 mass% of methanol solution of sodium hydroxide, 5-10 mass% of ethyl alcohol solution of sodium hydroxide, 5-8 mass% of methanol solution of potassium hydroxide, 5-8 mass% of ethanol solution of potassium hydroxide, 5-10 mass% of sodium hydroxide aqueous solution, 10-20 mass% of sodium chloride aqueous solution, 10-20 mass% of calcium chloride aqueous solution, 5-10 mass% of nitric acid aqueous solution, 5-10 mass% of calcium nitrate aqueous solution, 5-10 mass% of phosphoric acid aqueous solution, 5-8 mass% of potassium chloride aqueous solution, 5-10 mass% of ammonium chloride aqueous solution, and 5-15 mass% of aqueous ammonia.