溶胶-凝胶论文：溶胶—凝胶与纳米材料修饰电极及其电化学性质
【中文摘要】近年发展起来的溶胶-凝胶技术,其载体为无机多孔材料,具有许多高分子无法比拟的特性,为纳米材料的固定提供了更广阔的空间。纳米材料具有比表面积大、催化活性高、亲和力强等特点,在电催化及传感器材料领域有着广阔的应用前景。研究表明,电化学过程与电极材料的表面性质密切相关。由于该材料的尺寸效应和介电限域效应等特性,将纳米材料修饰到电极表面,能增加电流响应,降低检测限,大大提高检测的灵敏度。本论文致力于溶胶-凝胶与纳米材料修饰电极的制备及其电催化性能的研究,修饰电极过程简单、方便,实现了将溶胶-凝胶、纳米材料、修饰电极和电分析化学的有机结合。主要工作如下:1.3-氨丙基三乙氧基硅烷单层修饰电极及其表面非均相扩散:铂纳米花的形成及其电催化性质3-氨丙基三乙氧基硅烷在铂电极表面形成单层修饰膜,诱导铂纳米花在其表面形成。我们通过场发射扫描电镜、X-粉末衍射和电化学方法表征了得到的铂纳米花的性能。本工作细致探讨了铂纳米花的生长机理,可能的解释是PtCl62-离子在铂电极表面的不均匀扩散。我们还发现铂纳米花修饰电极比铂纳米修饰电极对甲醇的氧化和氧气的
【英文摘要】Recently, sol-gel-based nanomaterials and devices have been extensively applied in all kinds of fields due to their porous structure, good mechanical strength and
long-term stability.It is well-known that the electrochemical responses of modification electrodes are related to the electrode materials.Current response can be improved and detection limit can be extended when the nanomaterials modified electrodes are employed.The main work of this paper is focus on preparation of sol–gel-based materials and novel nanomaterials modified electrodes, which have been used to investigate the electrocatalytic properties.Compared with the traditional electrodes, the modification proce is simple and convenient.Moreover, the above proposed electrodes have been used to detect and analysize some analysts, such as methanol, oxygen, and hydrogen peroxide.The details are listed below:1.Inhomogeneous Diffusion on Electrode Surface Induced by （3-Aminopropyl）triethoxysilane Monolayer: the Formation of Pt Nanoflowers and its ElectrocatalysisHierarchical flowerlike Pt （Pt nanoflowers, PtNFs） nanostructures have been formed on the surface of Pt electrode induced by 3-aminopropyltriethoxysilane （APTES） monolayer.Scanning electron microscopy, X-ray powder diffraction, and electrochemical methods have been used to characterize the properties of these obtained PtNFs.The growth mechanism of the PtNFs has been discued carefully, which may be due to the
inhomogeneous diffusion of PtCl62- ions on the surface of Pt electrode.It has been found that the PtNFs modified electrodes exhibit excellent electrocatalytic activity towards the oxidation of methanol and the reduction of oxygen compared to Pt nanoparticles modified electrodes.The increased catalytic activity may be a result of the unique morphology of the PtNFs.2.Electrochemically deposited sol-gel-derived silicate films and the electrochemical properties of pore electrodeSol gel-derived silicate films were electrochemically deposited on conductive surfaces from a sol consisting of tetramethoxysilane （TMOS）.In this method, a sufficiently negative potential is applied to the electrode surface to reduce oxygen to hydroxyl ions, which serves as the catalyst for the hydrolysis and condensation of TMOS.The electrodeposited films were characterized for their surface morphology, electrochemical probe techniques.The electrodeposited films were found to have a completely different surface structure and to be significantly rougher relative to spin-coated films.This is likely due in part to the separation of the gelation and evaporation stages of film formation.The pore electrode was fabricated by electrodeposited in negative potential, which was
characterized by Scanning electron microscopy and electrochemical methods.The electrode was applied in biosensor fields.3.Electrochemical synthesis Au@Pt nanoparticles on choline chloride modified glay carbon electrode for sensitive detection hydrogen peroxideA simple electrochemical sensor for sensitive determination of hydrogen peroxide was fabricated by electrochemical synthesis of Au@Pt nanoparticles （core@shell） on the surface of choline chloride （Ch） modified glay carbon electrode （GCE）.Ch was used to combine metal ions, and also played a dual role of stabilizer in the construction of Au@Pt nanoparticles.Au nanoparticles was immobilized on the Ch by underpotential electrodeposition （UPD） proce.A one-atom-thick shell of Cu was modified on the Au core by electrochemical underpotential deposition, and then this modified electrode was put into H2PtCl6 solution, the Cu monolayer was replaced with Pt by galvanic exchange.The obtained Au@Pt nanoparticles were characterized by scanning electron microscope （FE-SEM）and electrochemical techniques.As a result, the Au@Pt （core@shell） exhibited remarkable electrocatalytic activity towards the reduction of hydrogen peroxide.Under the optimum conditions, Chronoamperometric experiments showed that at an applied potential of 10mV （AgCl）,
the reduction current of H2O2 was linear to its concentration in the range of 32uM to 2.496mM and a low detection limit of 1.0×10-6 M, the promising electrochemical sensor was investigated against ascorbic acid （AA） and uric acid （UA）, the results demonstrated that the sensor exhibited stability, repeatability, and selectivity.【关键词】溶胶-凝胶 纳米材料 修饰电极 电催化
【英文关键词】sol-gel nanomaterials modified electrode electrocatalysis 【目录】溶胶—凝胶与纳米材料修饰电极及其电化学性质要5-7ABSTRACT7-9
第一章 综述11-20
摘
1.1 溶胶-凝胶的制备、性质及应用11-12及应用12-161617-20
1.2 纳米粒子制备、性质
1.3 双金属核-壳结构纳米复合电极的构建
16-17
参考文献1.4 本论文的研究目的和设想第二章 3-氨丙基三乙氧基硅烷单层在电极表面非均相
20-39
2.1 前言散: 铂纳米花的形成及其电催化性质20-2122-342.2 实验部分21-222.4 结论34-35
2.3 结果与讨论参考文献35-39
第三章
电化学沉积四甲氧基硅烷膜孔状电极及其电化学性质39-483.1 前言39-40
3.2 实验部分40-41
参考文献47-48
3.3 结果与讨论41-473.4 结论47第四章 在胆碱修饰的玻碳电极上电化学合成 Aucore@ Ptshell 纳
米粒子用于双氧水的检测48-59实验部分49-5057
4.1 前言48-494.2
4.3 结果与讨论50-57
工作展望59-60
4.4 实验结论附录：研究参考文献57-59生期间发表论文及获奖情况60-61致谢61
