▎ 摘　　要

NOVELTY - A passivated modified sugarcane molasses graphene quantum dot is prepared by taking 1-4 g sugarcane molasses, adding ultrapure water to adjust volume to 30-50 mL, stirring and dissolving, ultrasonicating for 5-20 minutes, centrifuging at rate of 8000-12000 revolutions/minute for 5-15 minutes, taking out 15-25 mL supernatant, carrying out hydrothermal reaction at 160-190 degrees C for 20-28 hours, cooling, filtering, centrifuging product, obtaining resulting supernatant as graphene quantum dot solution, diluting with 10-100 times passivating agent, loading into fluorescence spectrophotometer at voltage of 500 to 650 V, excitation slit and emitting slit at 5 nm, and excitation wavelength of 350-390 nm, and obtaining product emitting blue light at highest fluorescence intensity of 430-460 nm, average particle size of 1.5-3.5 nm and thickness of 1-2 nm with graphene thickness of 3-6 layers. USE - The method for preparing passivated modified sugarcane molasses graphene quantum dot. ADVANTAGE - The method is simple, environment-friendly, low-cost and has easy to obtain raw materials. The product is suitable in biomedical and photoelectric fields. DETAILED DESCRIPTION - A passivated modified sugarcane molasses graphene quantum dot is prepared by taking 1-4 g sugarcane molasses, adding ultrapure water to adjust volume to 30-50 mL, stirring and dissolving, ultrasonicating for 5-20 minutes, centrifuging at rate of 8000-12000 revolutions/minute for 5-15 minutes, taking out 15-25 mL supernatant, carrying out hydrothermal reaction at 160-190 degrees C for 20-28 hours, cooling, filtering, centrifuging product, obtaining resulting supernatant as graphene quantum dot solution, diluting with 10-100 times passivating agent, loading into fluorescence spectrophotometer at voltage of 500 to 650 V, excitation slit and emitting slit at 5 nm, and excitation wavelength of 350-390 nm, and obtaining product emitting blue light at highest fluorescence intensity of 430-460 nm, average particle size of 1.5-3.5 nm and thickness of 1-2 nm with graphene thickness of 3-6 layers. The passivating agent is anhydrous methanol, anhydrous ethanol, analytical pure propanol, analytical pure n-butanol, and analytical pure polyethylene glycol-200.