▎ 摘　　要

NOVELTY - Reduced graphene is dispersed in water, to obtain 3 mg/mL graphene solution. 10 mu L Solution is pipetted to glassy carbon electrode center, dried and graphene is made to support on glassy carbon electrode surface, to obtain graphene-modified glassy carbon electrode. Then, electrochemical process is carried out by taking graphene-modified glassy carbon electrode as working electrode, platinum wire as auxiliary electrode, and saturated calomel electrode as reference electrode, to obtain copper/graphene nanocomposite-modified glassy carbon electrode. USE - Preparation of copper/graphene nanocomposite-modified electrode used in detection of ascorbic acid concentration (claimed). ADVANTAGE - The method efficiently and economically improves sensing area, surface electron transfer and conductivity of copper/graphene nanocomposite-modified electrode. The ascorbic acid has high electro-catalytic oxidizing effect. DETAILED DESCRIPTION - A glassy carbon electrode is polished using polishing cloth with water and aluminum powder for 3-5 minutes, surface of electrode is washed, and ultrasonically-cleaned in CNC ultrasonic cleaner for 4-8 minutes, to obtain pre-treated glassy carbon electrode. 600 mg Graphene oxide is dispersed in 600-1000 mL water, ultrasonically-vibrated for 1-2 hours, then 6-8 g hydrazine hydrate is added, and stirred at 80 degrees C for 10-12 hours under water bath condition. The reaction product is filtered using filtration membrane having pore size of 20 mu m, washed using predetermined amount of ethanol for 1-2 times and distilled water and vacuum-dried, to obtain reduced graphene. The reduced graphene is dispersed in water, to obtain 3 mg/mL graphene solution. 10 mu L Solution is pipetted to glassy carbon electrode center using micro syringe, dried using incandescent lamp, and graphene is made to support on glassy carbon electrode surface, to obtain graphene-modified glassy carbon electrode. Then, electrochemical process is carried out by taking 0.1-1 mol/L sodium sulfate solution containing 2x 10-3 mol/L copper sulfate, graphene-modified glassy carbon electrode as working electrode, platinum wire as auxiliary electrode, saturated calomel electrode as reference electrode, electrochemical work station sweep speed of 0.1 V/second, voltage of 0.6V to -0.6V and loop scanning of 15 laps, to obtain copper/graphene nanocomposite-modified glassy carbon electrode. An INDEPENDENT CLAIM is included for usage method of copper/graphene nanocomposite-modified electrode in detection of ascorbic acid concentration.