新型双金属纳米复合电极材料的构建及其对环境污染物的检测研究

发布时间：2018-05-16 19:38

本文选题：电化学传感器 + 同时检测　；参考：《辽宁大学》2017年硕士论文

【摘要】：环境污染物的分析与检测对环境保护和人类健康具有十分重要的意义。电化学方法相比于其他传统的检测手段来说,具有响应速度快、高灵敏、低成本和小型化等优点,已经在食品安全和环境保护等方面引起了广泛关注。本论文成功制备了ILs-CaFe_2O_4/MWCNTs、ZnFe_2O_4/SWCNTs和ILs@NiCo_2O_4-P三种新型双金属纳米复合电极材料,构筑新型环境污染物电化学传感器并建立了相关检测体系,实现了对农药多菌灵(CBZ)、噻菌灵(TBZ)和有毒金属(Tl~+、Pb~(2+)、Cu~(2+))的分析。本论文主要开展工作如下:合成ILs-CaFe_2O_4/MWCNTs纳米复合材料,建立了CBZ的电化学分析方法。该材料具有良好的分散性和导电性。运用循环伏安法(CV)探究了CBZ在修饰电极上的电化学行为,研究发现CBZ在ILs-CaFe_2O_4/MWCNTs/GCE上发生扩散控制的不可逆的氧化反应过程,且为两电子两质子参与的电化学过程。基于ILs-CaFe_2O_4和MWCNTs之间的协同作用,该传感器对CBZ的氧化表现出优异的电催化能力,大大提高了CBZ的电化学响应信号。研究了实验条件对CBZ电化学行为的影响。在pH 4.0的PBS中,CBZ的线性浓度范围是0.03~105.0μmol/L,检出限(LOD)为9.41 nmol/L(S/N=3)。该方法成功实现了苹果、西红柿和稻田水中CBZ的检测,加标回收率在94.7%到105.5%之间,并具有良好的稳定性和重现性。通过一步水热合成方法制备Zn Fe_2O_4/SWCNTs复合材料,构筑了Zn Fe_2O_4/SWCNTs/GCE传感器,应用于CBZ和TBZ的同时定量测定。该修饰电极具有高的导电性和大的电极表面积,有效提高了CBZ和TBZ与电极之间的电子转移能力。运用循环伏安法(CV)和差分脉冲伏安法(DPV)研究了CBZ和TBZ在ZnFe_2O_4/SWCNTs/GCE上的电化学行为。研究了不同因素对CBZ和TBZ电化学信号的影响,并探究了相关的电化学反应机理。结果表明,CBZ的电化学反应为吸附控制的准可逆的氧化还原反应过程,TBZ表现为扩散控制的不可逆的氧化反应过程。在pH 7.0的PBS中,CBZ和TBZ均在0.5~100.0μmol/L浓度范围内呈线性,LOD(S/N=3)分别为0.09和0.05μmol/L。该传感器成功应用于实际样品中CBZ和TBZ的同时测定,且具有良好的稳定性和抗干扰能力。成功制备三种形貌的NiCo_2O_4(NiCo_2O_4纳米粒子(NiCo_2O_4-N)、NiCo_2O_4纳米片(NiCo_2O_4-P)和NiCo_2O_4纳米微球(NiCo_2O_4-S))作为电极修饰材料。对比实验发现电化学性能依赖于电极材料的种类、形貌、比表面积等特征,因此,高表面的多孔性的NiCo_2O_4-P材料被选择作为电极材料。本实验中,用高导电的ILs代替传统的碳材料,结合高吸附性的NiCo_2O_4-P,构建ILs@NiCo_2O_4-P/GCE,实现了对Tl~+,Pb~(2+)和Cu~(2+)的同时检测。由于其具有独特的多孔结构、高的比表面积和良好的电子传导性,该修饰电极表现出优异的电化学活性。在pH 4.0的HAc-NaAc溶液中,运用差分脉冲溶出伏安法(DPASV)实现了对Tl~+,Pb~(2+)和Cu~(2+)的同时分析,T1+,Pb~(2+)和Cu~(2+)分别在0.1~100.0、0.1~100.0和0.05~100.0μg/L的浓度范围内表现出良好的线性关系,LOD(S/N=3)分别为0.046、0.034和0.029μg/L。传感器成功应用于水样和土壤样品中金属离子含量的测定,结果令人满意,具有实际应用价值。
[Abstract]:The analysis and detection of environmental pollutants is of great significance for environmental protection and human health. Compared with other traditional methods, electrochemical methods have many advantages, such as fast response, high sensitivity, low cost and miniaturization. It has attracted wide attention in food safety and environmental protection. This paper has been successful in this paper. Three kinds of new bimetal nanocomposite electrode materials ILs-CaFe_2O_4/MWCNTs, ZnFe_2O_4/SWCNTs and ILs@NiCo_2O_4-P were prepared to construct a new electrochemical sensor for environmental pollutants and establish a related detection system. The analysis of pesticide carbendazim (CBZ), TBZ (TBZ) and toxic metals (Tl~+, Pb~ (2+) and Cu~ (2+)) was analyzed. This paper was mainly carried out in this paper. The following work is as follows: the synthesis of ILs-CaFe_2O_4/MWCNTs nanocomposites and the electrochemical analysis of CBZ have been established. The material has good dispersion and conductivity. The electrochemical behavior of CBZ on the modified electrode is investigated by cyclic voltammetry (CV), and the irreversible oxidation of CBZ on ILs-CaFe_2O_4/MWCNTs/GCE has been found. The reaction process, and the electrochemical process involved in the two electron two protons. Based on the synergy between ILs-CaFe_2O_4 and MWCNTs, the sensor shows excellent electrocatalytic ability for the oxidation of CBZ and greatly improves the electrochemical response signal of CBZ. The influence of the experimental conditions on the electrochemical behavior of CBZ is studied. In the PBS of pH 4, the linearity of CBZ The concentration range is 0.03~105.0 mu mol/L and the detection limit (LOD) is 9.41 nmol/L (S/N=3). This method successfully realized the detection of CBZ in apple, tomato and rice field water, and the recovery rate was between 94.7% and 105.5%, and it had good stability and reproducibility. The Zn Fe_2O_4/SWCNTs composite was prepared by one step water heating method, and Zn Fe_2O was constructed. The _4/SWCNTs/GCE sensor is applied to the simultaneous quantitative determination of CBZ and TBZ. The modified electrode has high conductivity and large electrode surface area, which effectively improves the electron transfer ability between CBZ and TBZ and electrodes. The electrochemical behavior of CBZ and TBZ on ZnFe_2O_4/SWCNTs/GCE is studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The effects of different factors on the electrochemical signals of CBZ and TBZ were studied and the mechanism of the electrochemical reaction was explored. The results showed that the electrochemical reaction of CBZ was a quasi reversible redox reaction process of adsorption control, and TBZ was an irreversible oxidation reaction over the diffusion control. In PBS of pH 7, CBZ and TBZ were in 0.5~100.0 micron mo. The l/L concentration range is linear, LOD (S/N=3) is 0.09 and 0.05 mol/L. respectively. The sensor is successfully applied to the simultaneous determination of CBZ and TBZ in actual samples, and has good stability and anti-interference ability. The three morphologies of NiCo_2O_4 (NiCo_2O_4 nanoparticles (NiCo_2O_4-N), NiCo_2O_4 nanoscale (NiCo_2O_4-P) and NiCo_2O_4 Na) are successfully prepared. Mi Weiqiu (NiCo_2O_4-S) was used as an electrode modification material. The comparison experiment found that the electrochemical performance depended on the types, morphology, surface area and other characteristics of the electrode materials. Therefore, the porous NiCo_2O_4-P material on high surface was selected as the electrode material. In this experiment, the high conductivity ILs was used instead of the traditional carbon material and the high adsorptive NiCo_ was used. 2O_4-P, constructed ILs@NiCo_2O_4-P/GCE, realized simultaneous detection of Tl~+, Pb~ (2+) and Cu~ (2+). Because of its unique porous structure, high surface area and good electronic conductivity, the modified electrode showed excellent electrochemical activity. In HAc-NaAc solution of pH 4, the differential pulse stripping volt (DPASV) was used to realize the Tl. The simultaneous analysis of ~ +, Pb~ (2+) and Cu~ (2+) shows that T1+, Pb~ (2+) and Cu~ (2+) show a good linear relationship in the concentration range of 0.1~100.0,0.1~100.0 and 0.05~100.0 micron respectively. The results are successfully applied to the determination of metal ions in water samples and soil samples, respectively. The results are satisfactory. Practical application value.
【学位授予单位】：辽宁大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X830;O657.1

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