利用多巴胺的聚合及还原特性,制备聚多巴胺包覆还原氧化石墨烯,在氮气保护下煅烧,制得氮原位掺杂石墨烯(C/N-Graphene)。应用扫描电镜(SEM)、透射电镜(TEM)、傅里叶变换红外(FT-IR)光谱表征该复合物的形貌和结构。应用滴涂及Nafion膜固定法制备C/N-Graphene修饰玻碳电极(C/N-Graphene/GCE)。该修饰电极对苯二酚3种异构体的氧化反应表现出优异的电催化性能和选择性,差分脉冲伏安法(DPV)峰电流与对苯二酚(HQ)、邻苯二酚(CC)、间苯二酚(RC)的浓度呈良好的线性关系,其线性范围分别为0.5~1 000μmol/L、0.5~460μmol/L和0.1~580μmol/L,检出限分别为0.251μmol/L、0.144μmol/L和0.072μmol/L。该方法应用于药厂废水和江水检测,3种苯二酚异构体回收率为97.0%~103.0%,相对标准偏差(RSD)小于5%(n=5),结果表明C/N-Graphene/GCE修饰电极适用于污染水样的快速检测。
Polydopamine coated graphene oxide was prepared, and calcined under the nitrogen protection to obtain nitrogen doped graphene nanocomposite(C/N-Graphene). The morphology and structure of C/ N-Graphene were characterized by scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. C/N-Graphene was modified onto glassy carbon electrode as the working electrode (C/N-Graphene/GCE) to detect dihydroxybenzene isomer. A good linear relationship between differential pulse voltammetry peak current and the concentration of hydroquinone (HQ), catechol(CC) ,resorcinol(RC) was observed. Dihydroxybenzene isomer could be detected simultaneously with a wide linear range and low detection limits. The concentration of HQ, CC, RC in pharmaceutical wastewater and river water could be determined, the recovery was 97. 0%-103. 0% with the relative standard deviation less than 5%(n= 5). This indicates C/N-Graphene/GCE electrode could be used for the rapid determination of dihydroxybenzene isomers in waste.