▎ 摘　　要

NOVELTY - Preparing graphene film comprises (a) dispersing graphene oxide in water to obtain oxidized graphene suspension, (b) coating the graphene oxide suspension on a substrate and drying to obtain substrate loaded with graphene oxide film, (c) heating in an inert gas atmosphere at 800-1000 K, introducing ammonia gas, reducing at constant temperature to obtain graphene film loaded substrate, and (d) dissolving the graphene film loaded substrate in acid to obtain graphene film. USE - The graphene film is useful in a touch screen, a solar battery, a transparent conductive film of the organic light-emitting diode (OLED) or transparent conduction film (claimed). ADVANTAGE - The graphene film: improves the removal rate of epoxy group by using reducing agent e.g. hydrogen; has very good integrity after reducing the graphene film; and has stable performance. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for graphene film prepared by the above method.