▎ 摘　　要

NOVELTY - Photoreduction of fluorinated graphene film includes preparing graphene oxide powder; mixing graphene oxide powder and ethanol, ultrasonically dispersing, and spin-coating graphene oxide-ethanol solution on silica/silicon substrate to form large area graphene oxide thin film; reacting graphene oxide film and xenon difluoride to obtain fluorinated graphene thin film; and putting fluorinated graphene thin film in quartz boat, putting the quartz boat in photoreduction device, introducing ammonia gas, and illuminating with laser or mercury lamp to obtain high nitrogen-doped graphene thin film. USE - Method for photoreduction of fluorinated graphene film to obtain high nitrogen-doped graphene thin film (claimed). ADVANTAGE - The method is convenient to operate and has low cost. Nitrogen doping content and conductivity and band gap of graphene can be controlled by selecting illumination time, intensity and fluorine concentration. DETAILED DESCRIPTION - Photoreduction of fluorinated graphene film comprises: (A) uniformly mixing 6-10 g crystalline flake graphite, 6-10 g sodium nitrate and 350-400 ml concentrated sulfuric acid in ice bath; slowly adding 45-55 g potassium permanganate, magnetically stirring, and heating to 35 degrees C for 2 hours; and adding 320 ml deionized water, stirring for 15 minutes, adding 800 ml deionized water and 40 ml hydrogen peroxide, and stirring for 10 minutes to obtain green suspension; (B) adding 0.0001 mol/L dilute nitric acid solution to green suspension and centrifuging at 14000 revolutions/minute (rpm) to obtain precipitate; (C) repeating step (B) 2-3 times; (D) adding deionized water to the resulting suspension and centrifuging at 14000 rpm to obtain precipitate; (E) repeating step (D) 10 times to ensure no other impurity is present and to obtain graphene oxide solution; (F) condensing and drying graphene oxide solution to obtain graphene oxide powder; (G) mixing graphene oxide powder and 80-90 wt.% ethanol to obtain 1 mg/ml solution, and ultrasonically dispersing for 25-35 minutes to obtain graphene oxide-ethanol solution; and spin coating graphene oxide-ethanol solution on silica/silicon(SiO2/Si) substrate to form large area graphene oxide thin film, in which the thickness of SiO2/Si substrate is 0.5 mm, the thickness of SiO2 layer is 200-300 nm, the oxygen-to-carbon ratio in high oxygen-containing graphene oxide film is 2:5, and the thickness of graphene oxide film is 100-200 nm; (H) mixing graphene oxide film and 50-100 mg xenon difluoride, introducing into Teflon (RTM: PTFE)-lined stainless steel reactor, and reacting at 180 degrees C for 24-36 hours to obtain fluorinated graphene thin film; and (I) putting fluorinated graphene thin film in quartz boat, putting the quartz boat in photoreduction device including a transparent container, putting monochromatic or white light source of 200-760 nm on transparent container, introducing ammonia gas at 10-30 Torr, and illuminating with 65-75 mJ/cm2 laser or mercury lamp for 5-60 minutes to obtain high nitrogen-doped graphene thin film.