▎ 摘　　要

NOVELTY - Preparation of strip-shaped nitrogen-doped graphene comprises grinding sodium chloride/graphite mixed powder in agate mortar, washing with ultrapure water, filtering, removing sodium chloride solid for grinding, drying graphite, adding concentrated sulfuric acid, stirring, adding potassium permanganate while ice water bathing, stirring, heating, adding ultrapure water to dilute sulfuric acid, heating, stirring, adding ultrapure water and hydrogen peroxide respectively, reacting, removing unreacted potassium permanganate, pickling with hydrochloric acid aqueous solution, washing, removing unreacted sulfuric acid, dialyzing washed colloid, ionizing to obtain the graphene oxide colloid, and ultrasonically dispersing; adding ammonia water, graphene oxide colloid, and ultrapure water, mixing, sonicating, reacting, cooling, removing clear liquid upper layer, and taking black solid under layer; stirring to disperse uniformly, dialyzing, settling, and taking upper light tan liquid. USE - The method is for preparation of strip-shaped nitrogen-doped graphene used as enzyme-like catalyst for catalyzed oxidation of tetramethylbenzidine (claimed). ADVANTAGE - The strip-shaped graphene has neat edge structure and high efficiency as enzyme catalyst. DETAILED DESCRIPTION - Preparation of strip-shaped nitrogen-doped graphene comprises grinding 8-12 wt.% sodium chloride/graphite mixed powder in agate mortar for 10-20 minutes, washing with ultrapure water, filtering, removing sodium chloride solid for grinding, drying graphite at 60 degrees C for 24 hours, adding 98 wt.% concentrated sulfuric acid to prepare 12-15 mg/mL graphite/concentrated sulphuric acid solution, stirring for 20-25 hours, adding 20-30 wt.% potassium permanganate while ice water bathing, stirring for 25-35 minutes at 40 degrees C, heating to 90 degrees c for 40-50 minutes, adding ultrapure water to dilute sulfuric acid to 30-40%, finally heating to 105 degrees C, stirring for 20-30 minutes, adding 28 mL ultrapure water and 2 mL hydrogen peroxide respectively, reacting, removing unreacted potassium permanganate, pickling with 10% hydrochloric acid aqueous solution, washing with ultrapure water, removing unreacted sulfuric acid, transferring washed colloid to dialysis bag, dialyzing with 18.2 M-phm ultrapure water, ionizing to obtain the graphene oxide colloid, and ultrasonically dispersing; adding 5 mL ammonia water, graphene oxide colloid, and 25 mL ultrapure water in reaction kettle to obtain 20 mL graphene oxide reaction solution, uniformly mixing, sonicating, reacting in oven at 180-200 degrees C for 7-9 hours, cooling, removing clear liquid upper layer, and black solid under layer as nitrogen-doped graphene material; stirring in ultrapure water to disperse uniformly, dialyzing with ultrapure water to neutralize material pH value, settling, and taking upper light tan liquid as nitrogen-doped graphene nanomaterial.