新型电化学传感器检测环境有机污染物的应用研究

发布时间：2019-05-06 22:23

【摘要】：近年来,电化学传感器发展迅速,与其它分析方法相比,电化学检测法具有分析速度快、操作简单、省时且易于实现现场检测等优点。电极修饰材料作为传感器中最重要的一部分,受到许多研究人员的关注。本文成功合成NiFe2O4/MWCNTs、ILs@LiFe5O8/MWCNTs、ILs@CdFe2O4/Ni三种复合材料,构建新型有机污染物(农残苯菌灵(Benomyl)、双酚类污染物(双酚AP(BPAP)、双酚S(BPS))电化学传感器,建立了对农残和双酚类污染物的电化学分析方法,基本工作如下：一步水热法合成NiFe2O4/MWCNTs复合材料,构建NiFe2O4/MWCNTs修饰电极检测微量／痕量benomyl电化学传感器。计时库伦法研究表明,NiFe2O4/MWCNTs修饰电极的有效电催化活性表面积约为裸电极的6倍。采用循环伏安法(CV)和差分脉冲伏安法(DPV)探究benomyl的电化学行为,NiFe2O4/MWCNTs/GCE 对 benomyl表现出强的电催化效应,揭示电化学反应机制,其电极反应为吸附控制的准可逆电极过程,是两电子两质子参与的电化学反应。在pH6.0的PBS缓冲溶液中,benomyl峰电流与浓度在100×10-6mol/L～1.00×10-4mol/L范围内呈良好线性关系,检出限为2.51×10-7mol/L (S/N=3)。该方法被成功应用于食品样品中benomyl的检测,得到满意结果,加标回收率在93.2%-101.6%之间,相对标准偏差小于5.3%,该修饰电极在实际应用中具有良好的重现性、稳定性。本文建立的电化学传感器能准确、快速、灵敏地用于benomyl的监测。制备ILs@LiFe5O8/MWCNTs修饰电极,建立BPAP的电化学检测方法,实验引入离子液体(ILs)构建修饰电极,极大提高传感器的电流响应。用ILs@LiFe5O8/MWCN Ts修饰电极检测BPAP,结果表明,修饰电极对BPAP具有较强的电催化活性,BPAP的电极反应为吸附控制的不可逆电极过程,是两电子两质子参与的电化学反应。在pH 5.0的PBS缓冲溶液中,ILs@LiFe5O8/MWCNTs/GCE对BPAP的线性范围为1.034×10-9 mol/L～2.069× 10-6 mol/L,检出限为8.197x10-10 mol/L (S/N=3), ILs@LiFe5O8/MWCNTs/GCE成功用于对实际样品中BPAP的痕量分析,该方法制备的传感器具有良好的重现性,稳定性和抗干扰能力。成功制备Ni参杂CdFe2O4复合材料,引入具有较宽电化学窗口的离子液体(ILs)包覆CdFe2O4/Ni复合材料,成功构筑ILs@CdFe2O4/Ni修饰电极,建立同时检测B PAP和BPS的分析方法。探究BPAP和BPS在ILs@CdFe2O4/Ni/GCE的电化学行为,BPAP和BPS的氧化峰电位差为310mV,在pH 6.0的PBS缓冲溶液中,实现对BPAP和BPS的同时检测。ILs@CdFe2O4/Ni/GCE对BPAP的线性范围为6.89×10-9 mol/L～6.89×10-6 mol/L, BPAP的检出限为5.37×10-9mol/L (S/N=3); ILs@CdFe2O4/Ni/GCE对BPS的线性范围为8.00×10-9 mol/L～ 8.00 ×10-6 mol/L,检出限为7.19×10-9mol/L (S/N=3)。利用该方法对塑料牛奶袋、塑料果汁瓶及塑料包装袋进行检测,结果令人满意。ILs@CdFe2O4/Ni/GCE具有良好的重现性、稳定性和抗干扰能力,该方法具有快速、灵敏、方便的优点。
[Abstract]:In recent years, electrochemical sensors have developed rapidly. Compared with other analytical methods, electrochemical detection has the advantages of fast analysis speed, simple operation, time-saving and easy to realize on-the-spot detection. Electrode-modified materials, as the most important part of the sensor, have been concerned by many researchers. In this paper, three kinds of NiFe2O4/MWCNTs,ILs@LiFe5O8/MWCNTs,ILs@CdFe2O4/Ni composites were successfully synthesized, and a new type of organic pollutants (bisphenol AP-(BPAP), bisphenol S-(BPS) was constructed, which is a new kind of organic pollutant (bisphenol AP-(BPAP), bisphenol S-(BPS). A method for electrochemical analysis of agricultural residues and bisphenol pollutants was established. The basic work is as follows: one-step hydrothermal synthesis of NiFe2O4/MWCNTs composites and construction of NiFe2O4/MWCNTs modified electrode for detection of trace / trace benomyl electrochemical sensors. The effective electrocatalytic surface area of the NiFe2O4/MWCNTs modified electrode is about 6 times that of the bare electrode, according to the time-dependent Coulomb method. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to investigate the electrochemical behavior of benomyl. NiFe2O4/MWCNTs/GCE showed strong electrocatalytic effect on benomyl and revealed the mechanism of electrochemical reaction. The electrode reaction is a quasi-reversible electrode process controlled by adsorption, which is an electrochemical reaction involving two electrons and two protons. In the PBS buffer solution of pH6.0, there was a good linear relationship between the peak current of benomyl and the concentration in the range of 100 脳 10-6 mol / L ~ 1.00 脳 10-4mol/L, and the detection limit was 2.51 脳 10-7mol/L (S/N=3). The method has been successfully applied to the determination of benomyl in food samples with satisfactory results. The recovery of standard addition is between 93.2% and 101.6%, and the relative standard deviation is less than 5.3%. The modified electrode has good reproducibility in practical application. Stability. The electrochemical sensor developed in this paper can be used to monitor benomyl accurately, quickly and sensitively. The ILs@LiFe5O8/MWCNTs modified electrode was prepared and the electrochemical detection method of BPAP was established. The ionic liquid (ILs) was introduced to construct the modified electrode, which greatly improved the current response of the sensor. The results of BPAP, detection with ILs@LiFe5O8/MWCN Ts modified electrode show that the modified electrode has strong electrocatalytic activity for BPAP, and the electrode reaction of BPAP is an irreversible electrode process controlled by adsorption, which is an electrochemical reaction involving two electrons and two protons. In PBS buffer solution of pH 5.0, the linear range of ILs@LiFe5O8/MWCNTs/GCE to BPAP was 1.034 脳 10 ~ 9 mol/L~2.069 脳 10 ~ 6 mol/L, the detection limit was 8.197x10-10 mol/L (S/N=3). ILs@LiFe5O8/MWCNTs/GCE has been successfully applied to the trace analysis of BPAP in practical samples. The sensor prepared by this method has good reproducibility, stability and anti-interference ability. Ni-doped CdFe2O4 composites were successfully prepared. Ionic liquid (ILs) coated CdFe2O4/Ni composites with wide electrochemical window were introduced. The ILs@CdFe2O4/Ni modified electrode was successfully constructed and the analytical method for simultaneous detection of B-PAP and BPS was established. The electrochemical behavior of BPAP and BPS in ILs@CdFe2O4/Ni/GCE was investigated. The difference of oxidation peak potential between BPAP and BPS was 310 MV, and in pH 6.0PBS buffer solution, the oxidation peak potential difference between BPAP and BPS was 310 MV. The linear range of ILs @ CdFe2O4/Ni/GCE to BPAP is 6.89 脳 10-9mol/L ~ 6.89 脳 10 脳 10 ~ 6 mol/L, BPAP. The detection limit is 5.37 脳 10-9mol/L (S/N=3) for BPAP and BPS. The linear range of ils @ CdFe2O4/Ni/GCE to BPAP is 6.89 脳 10-9mol/L ~ 6.89 脳 10 ~ 6 mol/L, BPAP. The linear range of ILs@CdFe2O4/Ni/GCE for BPS is 8.00 脳 10-9mol/L ~ 8.00 脳 10 脳 6 mol/L, the detection limit is 7.19 脳 10-9mol/L (S/N=3). The method was used to detect plastic milk bags, plastic juice bottles and plastic bags with satisfactory results. Ils @ CdFe2O4/Ni/GCE has good reproducibility, stability and anti-interference ability. This method is rapid and sensitive. The advantage of convenience.
【学位授予单位】：辽宁大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：X830;O657.1

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