铅印迹介孔硅材料和CdSe量子点的制备及在铅离子分离检测中的应用

发布时间：2018-01-03 19:18

本文关键词：铅印迹介孔硅材料和CdSe量子点的制备及在铅离子分离检测中的应用　出处：《上海师范大学》2017年硕士论文　论文类型：学位论文

【摘要】：铅离子广泛存在于环境中,因其毒害性和在生物体中的可积累性,对人体和生物体构成了严重的威胁。目前,已用于实际的检测铅离子的方法往往具有前处理复杂、检出限高、选择性差等问题。因此,建立可靠、高灵敏、高选择性的分离和检测铅离子的方法具有重要意义。本论文制备了两种类型的功能化纳米材料:双吡唑基团功能化的铅离子印迹介孔硅材料和具有光学性质的巯基丙酸包被的硒化镉量子点(Cd Se QDs)。将功能化介孔硅材料用作固相萃取填充剂来选择性分离铅离子,并与电感耦合等离子体质谱(inductively coupled plasma-atomic mass spectrometry,ICP-MS)联用,实现了对水中铅离子分离与检测。其次,初步构建了基于Cd Se量子点的液相电致化学发光(electrochemiluminescence,ECL)检测铅离子的方法。详细工作包括以下三个方面的内容:1.设计并合成了三种含氮双齿配体修饰的铅离子印迹介孔硅材料。印迹材料均以4-(二(1-氢吡唑))甲基苯酚作为功能单体,铅离子为模板,3-异氰酸丙基三乙氧基硅烷为交联剂,不同形貌特征的介孔硅材料SBA-15、MCM-41和FDU-12分别做为固相载体,采用表面印迹技术,经模板洗脱后分别得到Pb-IIMS-SBA-15、Pb-IIMS-MCM-41和Pb-IIMS-FDU-12印迹介孔材料。经红外光谱、固态硅谱和碳谱的分析证明了功能单体已成功修饰于介孔材料表面;扫描电镜、透射电镜、X射线小角衍射和氮气吸附脱附等表征证明所得材料均保持原有介孔硅的形貌特征。通过能量色散X射线元素分析表明Pb-IIMS-MCM-41具有最高的含氮量。此外,三种相应的非印迹材料也成功制备。2.铅离子印迹介孔硅材料吸附性能的研究及其在水样分析中的应用。对铅印迹材料及相应的非印迹材料吸附量和选择性进行了考察,结果表明经印迹后的介孔硅材料在对铅离子的吸附量和选择性上确实均有明显的提高。吸附等温线和吸附动力学实验表明三种印迹材料对铅离子均具有较大的吸附量、较快的吸附速率,且吸附行为符合Langmuir等温线模型和准二级动力学模型。其中,Pb-IIMS-MCM-41具有最优的吸附性能及优良的可循环能力。因此,选取Pb-IIMSMCM-41为填充材料以构建固相萃取柱,并与电感耦合等离子体质谱(ICP-MS)联用,对水中的痕量铅离子进行检测,检出限为0.0150μg L~(-1),并在实际水样的检测中进行了应用,为选择性分离和检测水中铅离子提供了较为有效的方法。3.巯基丙酸包覆的硒化镉量子点(CdSe QDs)的合成及对铅离子检测。采用水热法,以巯基丙酸为稳定剂,新制备的镉前驱体溶液和硒前驱体溶液为原料,制备了水溶性Cd Se QDs,并优化了镉和硒前驱体的配比与合成时间。通过了紫外光谱、荧光光谱、红外光谱对Cd Se QDs进行了表征。考察了发光体系中的p H、电位扫描速度对Cd Se ECL信号的影响。在优化条件下测试了铅离子对Cd Se量子点ECL信号的响应,初步建立了一种液相ECL测定铅离子的方法,其检出限为0.35 n M(0.072μg L~(-1))。
[Abstract]:Lead ions exist widely in the environment, because of its toxicity and in the organism can accumulate, pose a serious threat to human and organism. At present, a method for detection of lead ion has actual tend to have complicated pretreatment, high detection limit, the problem of poor selectivity. Because of this, the establishment of a reliable, high sensitive is important method for highly selective separation and detection of lead ion. The functional nanomaterials two types this paper prepared: lead ion imprinted mesoporous silicon bipyrazole functionallization and optical properties of mercaptopropionic acid package CdSe quantum dots (Cd Se QDs) is the the functionalized mesoporous silica materials used as fillers to solid phase extraction and selective separation of lead ion, and inductively coupled plasma mass spectrometry (inductively coupled plasma-atomic mass spectrometry, ICP-MS) combined with the separation and detection of lead ion in water Test. Secondly, constructed based on Cd quantum dots Se liquid phase electrochemiluminescence (electrochemiluminescence, ECL) method for detection of lead ion. The detailed work includes the following three aspects: 1. design and synthesis of lead ion imprinted mesoporous silicon material three containing nitrogendentates imprinted material modification. In 4- (two (1- hydrogen pyrazole) methyl phenol) as functional monomer, lead ion as a template, 3- carbimide propyl triethoxysilane as crosslinking agent, SBA-15 mesoporous silica materials with different morphologies were MCM-41 and FDU-12 respectively, as the solid carrier, using surface imprinting technique after template removal after Pb-IIMS-SBA-15, Pb-IIMS-MCM-41 and Pb-IIMS-FDU-12 imprinted mesoporous materials. By infrared spectroscopy, solid-state silicon spectrum and carbon spectrum proved that the functional monomer has been successfully modified on the surface of mesoporous materials; scanning electron microscope, transmission electron microscope, X ray diffraction and small angle The nitrogen adsorption desorption characterization proved that the material remained the original morphology of mesoporous silica. By energy dispersive X ray elemental analysis showed that Pb-IIMS-MCM-41 had the highest nitrogen content. In addition, three corresponding non imprinted materials are also successful preparation of.2. lead ion imprinted mesoporous silicon adsorption and its application in water samples in the analysis of lead. Imprinted material and corresponding non imprinted material adsorption capacity and selectivity were investigated. The results show that the mesoporous silicon material after imprinting of lead ions on the adsorption capacity and selectivity is increased significantly. The adsorption isotherms and adsorption kinetics experiments showed that the three materials have imprinted adsorption the larger of lead ion, the adsorption rate is relatively fast, and the adsorption behavior with the Langmuir isotherm model and the quasi two level dynamic model. Among them, Pb-IIMS-MCM-41 has the best adsorption performance and Excellent cycle ability. Therefore, selecting Pb-IIMSMCM-41 as filling material to build a solid phase extraction column, and inductively coupled plasma mass spectrometry (ICP-MS) combined with trace lead ion in water were detected, the detection limit was 0.0150 g L~ (-1), and were used in the actual sample testing, provide the effective method of.3. mercaptopropionic acid coated CdSe quantum dots for selective separation and determination of lead ion (CdSe QDs) and the synthesis of lead ion detection. By hydrothermal method with 3-mercaptopropionic acid as stabilizer, cadmium and selenium precursor solution precursor solution was prepared as raw materials, preparation the water soluble Cd Se QDs, and the optimal ratio of cadmium and selenium precursors and synthesis time. UV spectra, the fluorescence spectra of Se by Cd, QDs was characterized by infrared spectroscopy. The research of the luminescence system p H, Cd Se ECL potential scan rate on the signal. The response of lead ions to Cd Se quantum dot ECL signal was tested under optimized conditions. A method for the determination of lead ion by liquid ECL was preliminarily established. The detection limit is 0.35 n M (0.072 g L~ (-1)).

【学位授予单位】：上海师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O658;TB383

【参考文献】