石墨烯的制备及石墨烯修饰电极对p-苯二酚的催化氧化

摘要

The graphene (GN) was prepared by reducing graphene oxide ( GO ) using ammonia solution, and the electrocatalysis on p-hydroquinone(HQ) was also investigated at graphene-modified electrode(GN/GCE). The molecular structure, interface morphology and electrochemical properties of GN were determined by FTIR, Raman, XRD, SEM, AFM, surface area analysis(BET) and electrochemical methods. The results show that the charge transfer resistance of [ Fe(CN)6]3-/4- at GN/GCE is 75.0Ω·cm2 decreased by 9 times as compared to that of the bare glass carbon electrode(GCE) , indicating that GN has good conductivity. Meanwhile, the oxidation peak potential of HQ has been shifted negatively and its reduction peak potential has been shifted positively, and the peak separation potential(△Ep) is decreased by 165 mV with the redox peak currents increasing significantly. It is concluded that the reversibility of HQ improves greatly and GN/GCE holds remarkable electrocatalytic activity toward HQ. The test method has provided an important inspection for in situ monitoring hazardous matter in food, environment and life fields.%采用氨水还原氧化石墨烯(GO)制备石墨烯(GN),并考察石墨烯修饰玻碳电极(GN/GCE)电催化氧化p-苯二酚(HQ)的性能.利用傅里叶红外光谱(FTIR)、拉曼光谱(Raman)、X射线衍射(XRD)、扫描电子显微镜(SEM)、原子力显微镜(AFM)、比表面分析(BET)和电分析化学测试等技术对GN结构、表面形貌和电化学行为进行了表征.采用循环伏安法(CV)和差分脉冲溶出伏安法(DPV)研究GN/GCE对HQ的电催化氧化性能.结果表明,与裸玻碳电极(GCE)相比,[Fe(CN)6]3-/4-在GN/GCE上电荷转移电阻为75.0 Ω·cm2,减小约9倍,说明GN具有良好导电性；同时HQ在GN/GCE上氧化峰电位负移,还原峰电位正移,峰电位差△Ep减小165 mV,且氧化还原峰电流(Ipa和/Ipc)均增大,HQ电化学氧化可逆性明显改善,表明GN/GCE对HQ氧化具有显著电催化作用.