▎ 摘　　要

NOVELTY - Preparing graphene-diamond composite film, comprises: (i) mixing graphene with poly(diallyldimethylammonium chloride); (ii) performing ultrasonic dispersion and centrifugal separation to the mixing liquid, carrying out vacuum drying on methanol dispersion solution of modified poly(diallyldimethylammonium chloride)-graphene to obtain poly(diallyldimethylammonium chloride)-graphene powder; (iii) dispersing poly(diallyldimethylammonium chloride)-graphene in methanol solution as an electrolyte, and performing reflux condensation and electrical deposition to obtain graphene-diamond composite film. USE - The composite film is useful as a electrode material in batteries and the capacitors. ADVANTAGE - The composite film obtained from the method has high efficiency and long service life. DETAILED DESCRIPTION - Preparing graphene-diamond composite film, comprises: (i) mixing graphene with poly(diallyldimethylammonium chloride), grinding graphene in the ultrasonic grinder to promote the combination of graphene and poly(diallyldimethylammonium chloride); (ii) performing ultrasonic dispersion to the mixing liquid in distilled water and performing centrifugal separation to the mixing liquid, then washing poly(diallyldimethylammonium chloride)-graphene in methanol solution, carrying out vacuum drying on methanol dispersion solution of modified poly(diallyldimethylammonium chloride)-graphene to obtain poly(diallyldimethylammonium chloride)-graphene powder; (iii) dispersing the poly(diallyldimethylammonium chloride)-graphene in the methanol solution as an electrolyte, taking a mono-crystalline silicon film as a cathode, a platinum plate as an anode and dipping in the electrolytic solution, performing reflux condensation under the protection of nitrogen gas and performing electrical deposition under constant voltage to obtain the graphene-diamond composite film.