▎ 摘　　要

NOVELTY - Preparation of graphene involves adding 2-3 g potassium persulfate and 2-3 g phosphorus pentoxide into 25 mL concentrated sulfuric acid, magnetically stirring, adding 1-3 g graphite, heating at 75-85 degrees C, magnetically stirring for 3-6 hours, cooling, adding 150-250 mL water to dilute, filtering, washing to neutral and vacuum drying at 60-90 degrees C;#adding 1-3 g pre-oxidized graphite to 40-50 mL concentrated sulfuric acid, cooling to 4-7 degrees C in ice bath, stirring, adding 5-7g potassium permanganate, reacting and heating. USE - Method for preparing graphene (claimed). ADVANTAGE - The method is simple; improves the Hummers oxidation-reduction method; and has high yield. DETAILED DESCRIPTION - Preparation of graphene comprises: (A) adding 2-3 g potassium persulfate and 2-3 g phosphorus pentoxide into 25 mL concentrated sulfuric acid, magnetically stirring, adding 1-3 g graphite, heating at 75-85 degrees C, magnetically stirring for 3-6 hours, cooling, adding 150-250 mL water to dilute, filtering, washing to neutral and vacuum drying at 60-90 degrees C; (B) adding 1-3 g pre-oxidized graphite to 40-50 mL concentrated sulfuric acid, cooling to 4-7 degrees C in ice bath, stirring, adding 5-7g potassium permanganate, reacting at less than or equal to 12 degrees C, adjusting temperature of the reaction solution to 35 degrees C, stirring at constant temperature for 1.5-2.5 hours, adding 90-95 mL deionized water, heating at 85 degrees C, reacting for 10-20 minutes, adding 250-300 mL deionized water to dilute, adding 15-30 mL of 30% hydrogen peroxide to remove unreacted potassium permanganate, performing hot filtration, taking product, washing with 10% hydrochloric acid, re-dispersing in deionized water, centrifugal washing, re-dispersing lower layer of precipitate into water and dialyzing for 3-5 days to completely remove the impurity ions in the solution; and (C) dispersing oxidized graphite in deionized water, ultrasonically centrifuging at speed of 3000-5000 revolutions/minute to remove undrawn oxidized graphite after 2-3 hours, taking upper solution as the graphene solution with concentration of 1 mg/mL, taking 80-120 mL graphene solution, magnetically stirring by adding 8-12 mL ammonia and 0.8-1.2 mL hydrazine hydrate, stirring at room temperature for 30 minutes, heating at 100-120 degrees C for 2-3 hours, cooling, filtering, washing and vacuum drying at 60-80 degrees C for 3-5 hours.