▎ 摘　　要

NOVELTY - A graphene quantum dot fluorescent film comprises graphene quantum dot aqueous solution with high fluorescence quantum yield of not less than 2 mg/mL dissolved in dimethylformamide or aqueous solution, and silane coupling agent KH-792. The graphene quantum dot aqueous solution with high fluorescence quantum yield is prepared by subjecting graphene quantum dots with high fluorescence quantum yield to solvothermal reaction with graphene oxide in dimethylformamide solvent, adding oxidant hydrogen peroxide to reaction product, continuously subjecting to solvothermal reaction. USE - The graphene quantum dot fluorescent film is used for preparing laser diode light emitting device (claimed). ADVANTAGE - The film can emit bright yellow fluorescence, and has high fluorescence quantum yield and high thermal stability. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) preparation of the film comprising dissolving graphene oxide powder in dimethylformamide solvent, subjecting to solvothermal reaction through airtight heating in reaction kettle to obtain light yellow solution, dropping hydrogen peroxide, and subjecting to second solvothermal reaction to obtain light yellow graphene quantum dot solution; vacuum distilling, putting to dialysis bag to purify with deionized water, freeze-drying to obtain graphene quantum dot yellow-brown powder, dissolving in dimethyl formamide or water to obtain not less than 2 mg/mL graphene quantum dot solution, adding silane coupling agent KH-792, dropping to mold, and curing; and (2) application of the film comprising compounding graphene quantum dot fluorescent film with blue semiconductor laser to obtain white laser diode light emitting device.