【作者】 谌创业；

【导师】 汪莉；

【作者基本信息】 江西师范大学 ， 有机化学， 2009， 硕士

【摘要】 多金属氧酸盐是一类与众不同的无机金属-氧簇化合物,其尺寸、成分和功能多样化,这类化合物具有各种确定的结构和优异的物理化学性质,在分析化学、生物化学、物理化学和催化化学等领域都有着重要的理论研究和实际应用价值,在当前的科学研究领域也是一个比较热门的课题。要想实现以多金属氧酸盐为基础材料的功能性质,发展一些新型的方法将它们固定在一定的基底上是当前该领域的热点和难点。本论文将多金属氧酸盐的材料优势和多种固定化方法相结合,成功地研制了多种具有应用前景的杂多酸修饰电极,并研究了其电化学及电催化性质,主要内容如下:1. Keggin型[SiNi(H2O)W11O39]6-修饰电极的电化学及其电催化行为我们首先在金电极上吸附半胱氨,然后通过电位扫描的方法将Keggin-Type [SiNi(H2O)W11O39]6-修饰到半胱氨上,构建了硅镍钨杂多酸修饰的金电极。我们采用原子力显微镜(AFM)和电化学方法对该修饰电极进行表征。AFM结果表明,[SiNi(H2O)W11O39]6-分子均匀沉积在金电极表面,形成多孔结构。循环伏安实验表明采用本方法可以实现杂多酸在电极表面的有效固定,并且该电极在pH (0–7.6)范围内能稳定存在。该修饰电极对不同的无机离子如BrO3?、NO2?及抗坏血酸(AA)具有优越的电催化能力。2.磷钼杂多酸和聚二茂铁硅烷多层组装膜修饰电极及其电化学行为采用层层组装法在金电极上组装多金属氧酸盐阴离子(POM)和聚阳离子聚二茂铁硅烷(PFS),交替沉积多层膜,构建了杂多酸-PFS多层膜修饰的金电极。我们采用原子力显微镜和电化学方法表征了该修饰电极的形貌特征和电化学行为,研究结果表明该修饰电极兼具杂多酸和PFS的双重功能。我们制备的多金属氧酸盐-PFS多层修饰电极对不同的无机离子如BrO3-、IO3-、NO2-、Fe3+和SO32-以及抗坏血酸等多种物质表现出优越的电催化能力,并且具有安培响应快、检测限低、选择性好以及线性范围宽等优点,该修饰对这些物质良好的催化能力主要归因于多金属氧酸盐-PFS杂化膜的多孔结构。3.杂多酸与胶原蛋白修饰电极的制备及其电催化性质研究采用层层组装法在金电极上组装I型胶原蛋白和杂多酸POMs交替沉积多层膜,构建了I型胶原蛋白-POMs多层膜修饰的金电极。我们采用原子力显微镜和电化学方法表征了该修饰电极的形貌特征和电化学行为,AFM结果表明PW12O403-优先沉积在胶原蛋白网络上形成了杂多酸的网络结构;电化学实验结果表明用该方法可以在电极表面有效地固定胶原蛋白和杂多酸分子,并表现出良好的电化学行为。我们所构造的修饰电极对亚硝酸盐有很好的电催化响应,并且具有安培响应快、检测限低、选择性好以及线性范围宽等优点。4.在中性溶液中构造多金属氧酸盐修饰电极及其电化学行为研究通过在金电极上逐步组装酞箐钴、聚二茂铁硅烷及Keggin型[SiNi(H2O)W11O39]6-构造了新型多金属氧酸盐修饰电极。我们采用原子力显微镜和电化学方法表征了该修饰电极的形貌特征和电化学行为,研究结果表明,采用该方法可以在电极表面有效地固定杂多酸分子。本方法所构造的修饰电极在中性条件下能够稳定存在,对氧气的还原和尿酸的氧化表现出优越的催化能力,有望用于电化学传感器。更多还原

【Abstract】 Recently, the considerable interests have been focused on polyoxometalates (POMs) clusters not only due to their special intrinsic structure but also due to their potential application in the field of material science, catalysis, biology and medicine. In order to promotes their applications in electrocatalytic research, develop some novel fabrication method to immobilize POMs on electrodes is a new challenge in this fields. The present reaserch work focused on the selecting and optimizing materials, improving immobilizing methods, and designing several types of novel polyoxometalates modified electrodes. The main points of this dissertation are addressed as follows:1. Electrochemical behavior and its electrocatalytic properties of chemically modified electrode with Keggin-type [SiNi(H2O)W11O39]6?A monolayer of Keggin-type heteropolyanion [SiNi(H2O)W11O39]6? was fabricated by electrodepositing [SiNi(H2O)W11O39]6? on cysteamine modified gold electrode. The monolayer of [SiNi(H2O)W11O39]6? modified gold electrode was characterizedby atomic force microscopy (AFM) and electrochemical method. AFM results showed the [SiNi(H2O)W11O39]6? uniformly deposited on the electrode surface and formed a porous monolayer. Cyclic voltammetry exhibited one oxidation peak and two reduction peaks in 1.0M H2SO4 in the potential range of ?0.2 to 0.7 V. The constructed electrode could exist in a large pH (0–7.6) range and showed good catalytic activity towards the reduction of bromate anion (BrO3?) and nitrite (NO2?), and oxidation of ascorbic acid (AA) in acidic solution. The well catalytic active of the electrode was ascribed to the porous structure of the [SiNi(H2O)W11O39]6? monolayer.2. A Novel Sensor Based on Layer-by-Layer Hybridized Phosphomolybdate and Poly(ferrocenylsilane) on a Cysteamine Modified Gold ElectrodeA novel sensor have been constructed by layer-by-layer hybridizing phosphomolybdate (POM) and poly(ferrocenylsilane) (PFS) on a cysteamine modified gold electrode. The properties and performance of the sensor have been measured by electrochemistry and atomic force microscopy in detail. The results showed that the constructed multilayers modified gold electrode combined the properties of POM and PFS, and exhibited good electrocatalytic ability to a series of inorganic ions, including BrO3-﹑IO3-﹑NO2-﹑Fe3+﹑ascorbic acid and SO32-. The well catalytic activity of the sensor was ascribed to the porous structure of hybrid POM-PFS multilayer. The resulted sensor exhibited extremely fast amperometric response, low detection limit, high selectivity and wide linear range to these analyses. 3. Type I Collagen /Polyoxometalate Composite Films on Cysteamine Modified Gold Electrode and Its Electrocatalytic PropertiesA novel multilayer of the type I collagen and PW12O403- was successfully fabricated. The type I collagen was firstly assembled on cysteamine modified gold electrode to form a network and then PW12O403- was electrodeposited on the modified electrode. By recycling the assembly and electrodeposition, the PW12O403- (collagen-PW12O403-)n modified electrode was prepared. Electrochemistry and atomic force microscopy (AFM) were used to characterize the PW12O403- (collagen-PW12O403-)n multilayer. AFM results showed that the PW12O403- preferentially deposited on the collagen network to produce the PW12O403- network. Electrochemical experiments results showed that the resulted electrode exhibited good electrochemical and electrocatalytic properties towards the reduction of nitrite. The electrochemical and electrocatalytic properties of modified electrode were investigated in detail.4. A Novel Strategy for the Construction of Polyoxometalate Modified Electrode and Its Electrochemical BehaviorsA novel polyoxometalate modified electrode is fabricated by immersing the gold electrode in the benzene solution of phthalocyanatocobalt(II), the solution of poly(ferrocenylsilane) and the solution of Keggin-type [SiNi(H2O)W11O39]6- stepwisely. The properties of the modified electrode have been investigated by atomic force microscopy (AFM) and electrochemical methods. AFM results show the modified electrode has been successfully covered by the three materials. The resulted electrode has good catalytic activity towards the reduction of oxygen (O2) and oxidation of uric acid.更多还原