几种复合物修饰电极的制备及其对水环境中有机污染物电化学传感研究

发布时间：2017-12-27 03:33

本文关键词：几种复合物修饰电极的制备及其对水环境中有机污染物电化学传感研究　出处：《江苏大学》2017年硕士论文　论文类型：学位论文

【摘要】：有机污染物是指对自然环境以及人类健康产生威胁的天然存在或者人工合成的化学物质。苯二酚,对硝基氯苯和对氨基苯酚由于大量生产与使用,已对环境造成污染,是典型的有机污染物,在水环境中浓度低、毒性大,引起了人们高度关注。因此,研究分析方法对其进行痕量检测具有重要的意义。目前,苯二酚,对硝基氯苯和对氨基苯酚的检测方法主要集中于色谱法、质谱法、免疫分析、毛细管电泳和光学分析,但是检测成本高、样品预处理步骤复杂、检测周期长、检测限较高。而电化学传感器操作简便快捷、性价比高、灵敏度高、检测限低、特异性好,已成为检测水环境中痕量有机污染物的重要方法之一。本文用玻碳(GC)电极作为基底传感器,设计了三种不同的电化学传感器用来检测水环境中的有机污染物:(1)通过电化学聚合精氨酸(L-Arg)单体,制得聚精氨酸(P-L-Arg)修饰的GC电极,利用扫描电镜(SEM)和电化学方法对P-L-Arg进行表征,证实了聚合物复合成功。研究构建了用于苯二酚三种异构体同时检测的高灵敏电化学传感器,在最优条件下,三种目标物的检测范围都是0.1μM~110μM,相关系数R分别为0.9860(对苯二酚)、0.9880(邻苯二酚)和0.9980(间苯二酚),检测限分别是0.01μM、0.03μM和0.1μM,具有很好的稳定性和重复性。并成功用于检测自来水和河水中的苯二酚异构体,实际水样检测的相对标准偏差小于5.5%,回收率为89.5%~103%。(2)采用湿化学法将含氧基团功能化修饰到碳纳米角(CNHs)表面,通过部分剥离制备了CNHs/氧化石墨烯(GO)复合材料。通过透射电镜(TEM)、拉曼光谱仪(Raman)、X-射线衍射仪(XRD)和电化学方法对材料进行表征,证实了材料复合成功。利用CNHs良好的电化学性质、大的比表面积、特殊的内部结构和GO优异的导电性、良好的分散性,研究构造了用于对硝基氯苯(PCNB)高灵敏检测的电化学传感器。检测结果表明,PCNB的检测范围是0.1μM~90μM,检测限是0.01μM,相关实验系数R为0.9826。并成功用于检测实际水样中的PCNB,实际水样的相对标准偏差小于5.18%,回收率为96.5%~99.1%。(3)通过多巴胺(DA)在二氧化硅(SiO_2)表面自发聚合得到聚多巴胺(PDA)/SiO_2。利用带正电的PDA和带负电的GO之间的静电吸引作用,将GO修饰到PDA/SiO_2表面,高温碳化后用氢氟酸(HF)将SiO_2刻蚀得到石墨烯(GN)/掺氮空心碳球(NHCS),最后还原氯金酸,将金纳米颗粒(AuNPs)修饰到GN/NHCS材料表面制得AuNPs/GN/NHCS复合材料。采用TEM、Raman、XRD和电化学方法进行表征,证实了材料复合成功。利用NHCS良好的电化学性质、大的比表面积、较强的吸附能力,GN良好的导电性和AuNPs很好的电催化活性,研究构造了高灵敏检测对氨基苯酚(4-Ap)的电化学传感器。4-Ap的线性范围为0.1μM~40μM,相关系数R为0.9989,检测限为0.01μM。该传感器成功用于检测河水中的4-Ap,相对标准偏差小于5.4%,回收率为92.5%~101.6%。
[Abstract]:Organic pollutants are natural or synthetic chemicals that pose a threat to the natural environment and human health. Hydroquinone, p-nitrochlorobenzene and p-aminophenol due to a large number of production and use, has caused pollution to the environment, is a typical organic pollutants, low concentration in water toxicity, aroused great concern. Therefore, it is of great significance to study the analysis method for trace detection. At present, hydroquinone, nitrochlorobenzene and detection method of p-aminophenol mainly concentrated on chromatography, mass spectrometry and immunoassay analysis, capillary electrophoresis and optical detection, but the cost is high, the sample pretreatment steps of complex, long test cycle, high detection limit. Electrochemical sensors are simple, fast, cost-effective, sensitive, low detection and specific, and have become an important way to detect trace organic pollutants in water environment. This glassy carbon electrode as the substrate (GC) sensor, designed three kinds of organic pollutants in different electrochemical sensor for detecting water environment: (1) by electrochemical polymerization of arginine (L-Arg) monomer, preparation of poly arginine (P-L-Arg) GC modified electrode, using scanning electron microscopy (SEM) electrochemical methods and characterization of P-L-Arg, confirmed the success of polymer composite. Study on the construction of a highly sensitive electrochemical sensor for simultaneous detection of three isomers for hydroquinone, under the optimal conditions, the detection range of three target is 0.1 mu M~110 mu M, the correlation coefficient R was 0.9860 (hydroquinone), 0.9880 (catechol) and 0.9980 (benzene two phenol), the detection limit is respectively. 0.01 M, 0.03 M and 0.1 M, has good stability and repeatability. And for the success of dihydroxybenzene isomers detected in tap water and river water, the relative standard deviation of actual water samples is less than 5.5%, the recovery rate was 89.5%~103%. (2) the functionalized oxygen group was functionalized to the surface of carbon nanometers (CNHs) by wet chemical method, and CNHs/ graphene oxide (GO) composite was prepared by partial peeling. The materials were characterized by transmission electron microscopy (TEM), Raman spectroscopy (Raman), X- ray diffractometer (XRD) and electrochemical methods, which confirmed the success of the composites. An electrochemical sensor for high sensitivity detection of p-nitrochlorobenzene (PCNB) has been developed by using CNHs's good electrochemical properties, large specific surface area, special internal structure, excellent conductivity and good dispersion of GO. The detection results show that the detection range of PCNB is 0.1 mu M~90 mu M, the detection limit is 0.01 mu M, and the relative experimental coefficient R is 0.9826. It has been successfully used to detect PCNB in the actual water samples. The relative standard deviation of the actual water sample is less than 5.18% and the recovery rate is 96.5%~99.1%. (3) polydopamine (PDA) /SiO_2 is obtained by spontaneous polymerization of dopamine (DA) on the surface of silicon dioxide (SiO_2). The positively charged PDA and electrostatic interaction between the negatively charged GO attraction, GO was modified on the surface of PDA/SiO_2 after high temperature carbonization with hydrofluoric acid (HF) SiO_2 (GN) etching to obtain graphene / nitrogen doped hollow carbon spheres (NHCS), the reduction of gold chloride acid, gold nanoparticles (AuNPs) modified to the surface of GN/NHCS AuNPs/GN/NHCS composite material. The materials were characterized by TEM, Raman, XRD and electrochemical methods, which confirmed the success of the composites. A highly sensitive electrochemical sensor for detection of p-aminophenol (4-Ap) has been developed by using NHCS's good electrochemical properties, large specific surface area, strong adsorption capacity, good conductivity and good electrocatalytic activity of GN. AuNPs has been applied to the detection of p-aminophenol (4-Ap). The linear range of 4-Ap is 0.1 mu M~40 mu M, the correlation coefficient R is 0.9989, and the detection limit is 0.01 mu M. The sensor has been successfully used to detect 4-Ap in river water. The relative standard deviation is less than 5.4% and the recovery rate is 92.5%~101.6%.
【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O657.1;X832

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