▎ 摘　　要

NOVELTY - Preparation of small-size nitrogen-doped graphene photocatalyst comprises dissolving graphite oxide in deionized water, ultrasonically dispersing to obtain graphene oxide solution, dispersing 20 mg sodium hydroxide in 80 mL graphene oxide solution, mixing and stirring for 1 hour, adding 0.5 mL hydrazine hydrate, putting solution in kettle, hydrothermally reacting at 100 degrees C for 12 hours, cooling reaction liquid to room temperature, putting in dialysis bag, performing dialysis to ion concentration of less than 10 ppm, filtering, washing with deionized water and drying sample. USE - Method for preparing small-size nitrogen-doped graphene photocatalyst used for degradation of organic dye rhodamine B (claimed). ADVANTAGE - The photocatalyst has particle size of 300 nm, good organic pollutant degrading activity under visible light illumination, simple and easy preparation and low cost, and solves environmental pollution and energy shortage problems.