▎ 摘　　要

NOVELTY - Preparation of nitrogen-doped reduced graphene involves dissolving urea in deionized water, adding graphene oxide to urea solution, mixing, adding isopropanol, adjusting pH of obtained solution to 8-10 using aqueous ammonia, stirring, adding resultant mixed solution into sealed container, introducing nitrogen gas to saturate nitrogen in the solution, subjecting the nitrogen saturated mixed solution to irradiation treatment, washing the reaction product with ethanol and distilled water, performing centrifuging, repeating above process several times, and drying obtained residue. USE - Preparation of nitrogen-doped reduced graphene (claimed). ADVANTAGE - The method enables simple and economical preparation of nitrogen-doped reduced graphene having improved supercapacitor performance under mild conditions by environmentally-friendly process without using toxic solvent. The raw materials are readily available. DETAILED DESCRIPTION - Preparation of nitrogen-doped reduced graphene involves weighing predetermined amount of urea by electronic balance, dissolving urea in deionized water to obtain 10-25 g/L urea solution, adding predetermined amount of graphene oxide to urea solution, placing mixed solution in ultrasonic oscillator and mixing for 1-2 hours, adding 1-3 mL isopropanol to mixed solution, adjusting pH of obtained solution to 8-10 using predetermined amount of aqueous ammonia solution, then stirring in a magnetic stirrer for 10-30 minutes, adding resultant mixed solution into sealed container, introducing nitrogen gas for 10-30 minutes to saturate nitrogen in the solution, subjecting the nitrogen saturated mixed solution to irradiation treatment under electron beam of 2.5 MeV and 40 mA generated by an electron accelerator, where irradiation dose is 210-500 KGy, washing the reaction product with ethanol and distilled water, centrifuging at high speed to remove unreacted ions, repeating above process several times, and drying obtained residue in vacuum oven at 40-80 degrees C for 4-8 hours. The mass ratio of graphene oxide and urea is 1:5-3:5.