▎ 摘　　要

NOVELTY - N-Doped graphene-modified electrode is prepared by dispersing nitrogen-doped graphene in ultrapure water, applying 5 mu l dispersion liquid to electrodes and drying. The capacitance and cycle performance of nitrogen-containing graphene are tested with electrochemical workstations and three-electrode system, using nitrogen-doped graphene-modified electrode as working electrode, platinum plate as electrode, saturated calomel electrode as reference electrode and sulfuric acid solution as electrolyte. The capacitance of nitrogen-doped graphene is calculated by chronopotentiogram. USE - Preparation of nitrogen-doped graphene (claimed). ADVANTAGE - The method enables preparation of nitrogen-doped graphene having suppressed agglomeration and excellent capacitance and durability. DETAILED DESCRIPTION - A nitrogen-doped graphene is prepared by adding graphene oxide to N,N-dimethylformamide, ultrasonically dispersing mixture, adding pyridine-2,6-dicarboxylic acid, 2,6-diaminopyridine and N,N'-dicyclohexylcarbodiimide to dispersion, homogeneously stirring mixture, adding dispersion to 100 mL high-pressure reactor, passing nitrogen for half an hour, sealing reactor in oven, adding sodium borohydride to solution, reacting at room temperature, centrifuging mixture, washing mixture with water, freeze-drying mixture and calcining freeze-dried product. N-Doped graphene-modified electrode is prepared by ultrasonically dispersing nitrogen-doped graphene in ultrapure water, applying 5 mu l dispersion liquid having concentration of 1 mg/mL to electrodes and drying at room temperature. The capacitance of nitrogen-containing graphene is tested with electrochemical workstations and three-electrode system, using nitrogen-doped graphene-modified electrode as working electrode, platinum plate as electrode, saturated calomel electrode as reference electrode and sulfuric acid solution as electrolyte. The specific capacitance of nitrogen-doped graphene is calculated by chronopotentiogram. The cycle performance of nitrogen-doped graphene is calculated in electrochemical workstations and three-electrode system using nitrogen-doped graphene-modified electrode as working electrode, platinum plate as electrode, saturated calomel electrode as reference electrode, sulfuric acid solution as electrolyte. The specific capacitance of nitrogen-doped graphene at different charge-discharge times is calculated by chronopotentiometry.