▎ 摘　　要

NOVELTY - The method for improving water dispersibility of graphene, involves adding concentrated nitric acid and concentrated sulfuric acid to obtain mixed acid solution, adding graphite powder, centrifuging to obtain filtrate, washing with distilled water, drying to obtain product (A), mixing product (A) and potassium hydroxide, rinsing with distilled water, drying, dissolving oxidized porous graphene in distilled water to obtain graphene dispersion, adding oxidant solution to obtain solution (B), centrifuging, washing with distilled water and drying to obtain porous graphene. USE - Method for improving water dispersibility of graphene. ADVANTAGE - The method enables improving water dispersibility of graphene with improved carbon-oxygen ratio, excellent water dispersibility and specific surface area increased by 4 times. DETAILED DESCRIPTION - Method for improving water dispersibility of graphene, involves (S1) adding concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 1:2 to obtain mixed acid solution, (S2) adding graphite powder to mixed acid solution in solid-liquid ratio of 2-5:40-90 g/mL, heating at 0-4 degrees C in ice water bath for 30 minutes, transferring to water bath at 25-40 degrees C for 48 hours, centrifuging the reaction solution to obtain filtrate, washing the filtrate with distilled water to obtain cleaning solution, adjusting pH to 7.0, drying to obtain product (A), (S3) mixing product (A) and potassium hydroxide in a mass ratio of 1-1.5:4-5, grinding evenly, placing under nitrogen atmosphere, heating at 750-900 degrees C at the rate of 5-10 degrees C/minute for 2-3 hours, cooling to room temperature, rinsing with distilled water, adjusting pH to 7.0, drying to obtain oxidized porous graphene, (S4) dissolving oxidized porous graphene in distilled water, ultrasonically dispersing at 35-65 degrees C for 1-2 hours to obtain 0.05-0.1 g/L graphene dispersion, (S5) adding oxidant solution to graphene dispersion, ultrasonically processing to obtain solution (B), centrifuging to obtain filtrate, washing the filtrate with distilled water until the cleaning solution is colorless and drying to obtain porous graphene.