多孔金属纳米粒子的制备及电化学应用

发布时间：2018-01-21 07:27

本文关键词： 多孔纳米粒子 Galvanic置换溶出伏安法电化学传感器 Hg~（2+） H_2O_2　出处：《苏州大学》2015年硕士论文　论文类型：学位论文

【摘要】：纳米材料作为一种新型材料,在传感器、催化、光学等领域具有广阔的应用前景。这些性能与其形貌结构密切相关,特别是具有孔洞结构的纳米材料。作为纳米多孔材料的一个重要组成部分,纳米多孔金属因其高度有序的网状结构以及均匀的孔径分布而在电化学传感器领域有着非常重要的实际应用。而多孔金属纳米粒子,一种既具有纳米多孔结构,又具有纳米尺寸的新型纳米结构,不仅可以增加目标分子的有效反应面积,而且可以提高电子的迁移速率,利用这一特性可以制备高灵敏度的电化学传感器。本论文主要包括两部分内容:1.首先利用循环伏安法在氧化铟锡(ITO)导电玻璃表面直接电沉积银纳米粒子(Ag NPs),然后将制备好的Ag NPs/ITO与HAuCl4溶液通过Galvanic置换反应制备多孔金纳米粒子(Au PNPs),并对其进行了一系列的表征,如紫外-可见吸收光谱,扫描电子显微镜,原子力显微镜,循环伏安法,X射线衍射等。以Au PNPs/ITO电极为工作电极,使用差示脉冲溶出伏安法系统研究了该传感器对Hg2+的响应。实验结果表明,在优化的实验条件下,该传感器在Hg2+浓度为0.1-10μg/L范围内呈线性,检出限为0.03μg/L(S/N=3)。将其应用于不同实际样品的检测,也得出了令人满意的结果。2.利用Galvanic置换反应制备多孔金-铂纳米粒子(Au-Pt PNPs)。首先Ag NPs/ITO电极与HAuCl4溶液通过Galvanic置换反应制备Au-Ag PNPs/ITO电极,然后再与H2PtCl6溶液反应置换出剩余的银,得到Au-Pt PNPs/ITO电极,并比较了Au PNPs/ITO电极和Au-Pt PNPs/ITO电极对直接电氧化H2O2的催化性能。实验结果表明,与Au PNPs/ITO电极相比,Au-Pt PNPs/ITO电极对H2O2表现出较高的电催化性能和检测灵敏度,其线性检测范围为0.002mM-3mM,检出限为0.6μM(S/N=3),有望应用于实际样品的检测。
[Abstract]:Nanomaterials as a new type of materials have a broad application prospect in sensor, catalysis, optics and other fields. These properties are closely related to their morphology and structure. As an important part of nano-porous materials, especially nano-materials with porous structure. Nano-porous metal has a very important practical application in the field of electrochemical sensor because of its highly ordered network structure and uniform pore size distribution, while porous metal nanoparticles, a kind of nano-porous structure. The new nanostructures with nanometer size can not only increase the effective reaction area of the target molecule, but also improve the electron transfer rate. The electrochemical sensors with high sensitivity can be fabricated by using this characteristic. This thesis mainly includes two parts: 1. First, we use cyclic voltammetry to prepare indium tin oxide (ITO). Silver nanoparticles (Ag NPs) were directly electrodeposited on the surface of conductive glass. Then the prepared Ag NPs/ITO and HAuCl4 solution were prepared by Galvanic replacement reaction to prepare au PNPs. A series of characterization were carried out, such as UV-Vis absorption spectrum, scanning electron microscope, atomic force microscope, cyclic voltammetry. The response of the sensor to Hg2 was studied by differential pulse stripping voltammetry using au PNPs/ITO electrode as working electrode. Under the optimized experimental conditions, the sensor is linear in the range of 0.1-10 渭 g / L of Hg2 concentration. The detection limit is 0.03 渭 g 路L ~ (-1) / L ~ (-1) S / N ~ (3) N ~ (3 +). It has been applied to the detection of different samples. Satisfactory results were obtained. 2. Porous au Pt nanoparticles were prepared by Galvanic replacement reaction. Firstly, Ag NPs/ITO electrode and HAuCl4 solution were used to prepare Au-Ag PNPs/ITO electrode by Galvanic replacement reaction. The residual silver was then replaced with H _ 2PtCl _ 6 solution to obtain Au-Pt PNPs/ITO electrode. The catalytic properties of au PNPs/ITO electrode and Au-Pt PNPs/ITO electrode for direct electrooxidation of H2O2 were compared. Compared with au PNPs/ITO electrode, the Au-Pt PNPs/ITO electrode showed higher electrocatalytic performance and higher detection sensitivity to H _ 2O _ 2. The linear detection range is 0.002mM-3mM, and the detection limit is 0.6 渭 m ~ (-1) S / N ~ (3 +), which is expected to be applied to the detection of practical samples.
【学位授予单位】：苏州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;O646

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