High-heat-conductivity heat-dissipation composite film and preparation method thereof

The invention provides a high-thermal-conductivity heat dissipation composite film and a preparation method thereof. The preparation method comprises the following steps: preparation of a graphene oxide solution containing a plurality of graphene oxides; preparation of a nanoparticle solution containing a plurality of nanometer initial composite structures, wherein each of the nanometer initial composite structures comprises a plurality of nanometer diamonds coated with polydopamine layers; mixing operation: mixing the graphene oxide solution and the nanoparticle solution to form a mixed solution; preliminary film forming operation: performing suction filtration on the mixed solution, and reserving the mixed graphene oxides and nanometer initial composite structures to form a preliminary film; and heat treatment operation: heating the preliminary film to reduce the graphene oxide into a plurality of reduced graphene, and allowing the polydopamine layers of the nanometer initial composite structures to become