▎ 摘　　要

NOVELTY - A graphene thin film is prepared by carrying out pretreatment process, oxidation process, reduction process, modification process and membrane measurement process. USE - Graphene thin film is used for electrical devices and electrodes. ADVANTAGE - The grapheme thin film with controllable conductivity is prepared. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of graphene thin film, which involves mixing (in g) graphite (1), phosphorus pentoxide (2), concentrated sulfuric acid (3-5 ml) and potassium persulfate (1), oxidizing at 80 degrees C for 30 minutes, cooling to room temperature, diluting the mixture using distilled water (15-20 ml), leaching, filtering, washing filter cake by distilled water and drying, mixing the dried filter cake (2) with concentrated sulfuric acid (40-50 ml) at 0 degrees C, slowly adding potassium permanganate powder (5-6), continuously stirring, controlling the temperature to 20 degrees C or less by ice-bath, and reacting at 35 degrees C for 2 hours under oil bath, diluting reaction mixture by distilled water, continuously reacting for 15 minutes, finally adding distilled water (250-300 ml), adding 30% hydrogen peroxide solution (5 ml), leaching while hot and washing by hydrochloric acid solution (250 ml), preparing graphene dispersion by diluting graphene oxide (20 mg) with distilled water, regulating the pH to 9-11 by adding aqueous ammonia, adding 20-40 mu l of hydrazine hydrate, heating and reacting for 1-2 hours in oil bath, preparing diazonium salt by dissolving aniline solution (0.9 ml) in a mixture of concentrated hydrochloric acid (3-6 ml) and distilled water (14 ml), cooling to 0 degrees C by ice-salt bath, slowly dripping sodium nitrite solution obtained by dissolving sodium nitrite (0.752) in distilled water (4 ml), filtering reaction mixture to obtain filtrate, adding sodium fluoroborate into filtrate, cooling to 0 degrees C or less by ice-salt bath, leaching and flushing by ice water and cold diethyl ether, mixing the graphene dispersion and diazonium salt, reacting for 1 hours at low temperature, leaching the reacted miscible liquid by aqueous phase film, washing fully by distilled water, natural drying for 6-12 hours in the air, and then vacuumizing.