【作者】 黄峰；

【导师】 于爱民； 张志权；

【作者基本信息】 吉林大学 ， 分析化学， 2007， 博士

【摘要】 液/液界面上的电荷转移过程是目前电化学和电分析化学领域的研究热点之一。本文简要地回顾了液/液界面电分析化学研究的发展历程,介绍了液/液界面电分析化学的基本理论。围绕扫描电化学显微镜和微电极技术,结合分子筛膜,磷脂仿生膜等新材料分别研究了液/液界面上的电荷转移反应。1将含有氧化还原电对的水溶液液滴支持在铂电极上,然后将电极插入到有机溶液中,与参比电极和对电极构成常规的三电极系统。利用扫描电化学显微镜（SECM）,以铁氰化钾/亚铁氰化钾为氧化还原电对研究了铁氰化钾与TCNQ阴离子自由基之间的电子转移反应,成功地将扫描电化学显微镜与极化的液/液界面研究结合起来。2采用了一种全新中性β型纯硅分子筛膜修饰液/液界面,研究了水/1,2-二氯乙烷界面上的离子转移反应。采用三电极系统,研究了碱金属离子和TMA⁺在界面上的转移过程,实验表明离子转移不受膜存在的影响,该项工作可以测量一系列亲水离子在界面上的转移电位,拓宽液/液界面的研究领域。3以一种人工磷脂二甲基二（十二烷基）溴化铵为制备磷脂膜的材料,在玻碳电极上成功制备了双层磷脂膜。该膜在ClO₄^-存在时表现出较为敏感的通透性变化,所产生的通道电流大小不仅与ClO₄^-浓度有关,也与时间有关。同时应用扫描电化学显微镜（SECM）研究了该双层类脂膜的离子通道行为。4在n-Si（1 1 1）表面修饰了端基为羧基和磺酸基的直链羧酸和磺酸。研究了光电流密度,平带电位(U_fb)和修饰硅片碳链长度之间的关系。同时利用硅片作为固体基底修饰上了聚丙稀酰铵薄膜,通过结合金属离子Pb²⁺和Cd²⁺形成大分子金属复合物,使用光电子能谱、原子力显微镜、紫外可见光谱等表征了其表面形貌。更多还原

【Abstract】 Studies of charge （electron and ion） transfer across a liquid/liquid interface （L/L interface） by scanning electrochemical microscopy （SECM） is one of the novel areas in electrochemistry and electroanalytical chemistry. In my Ph. D. dissertation, the progress and historical background of this area is briefly reviewed, The main results are as follows:A L/L interface supported on a metallic electrode has been used to study electron ET reactions by SECM. The system is composed of an aqueous droplet adhered on a platinum disc electrode and immersed into an organic electrolyte solution. The ET reactions between 7,7,8,8-tetracyanoquinodimenthane radical anion （TCNQ.-） in organic solution and ferricyanide in aqueous solution have been investigated on SECM controlled by the externally polarized potential. The apparent heterogeneous rate constants for the ET reactions extracted by fitting the SECM experimental approach curves to the theoretical values obey the Butler-Volume formula in some ranges, and they are found to be potential dependent. This method enables a fast and convenient method to measure ET and IT reactions kinetic parameter.The modification of the water/1,2-dichloroethane interface with a new typeβzeolite membrane is studied. As a means of investigating the analytical potential of this interface the facilitated transfer of various alkali and alkaline earth metal ions have been investigated using voltammetric methods. This work allows the observation of the transfer of extremely hydrophilic ions, due to the size-exclusion of organic ions from the interior of the zeolitic framework. Additionally. volume exclusion effects are shown to affect facilitated ion transfer processes involving alkali metal cations. It is hoped to extend this study to investigate the diffusion of ions within the zeolite pores with electrochemical methods, and to apply these properties to size selective sensors.A kind of didodecyldimethylammonium bromide （a synthetic lipid） layer membranes was supported on a glassy carbon electrode. We studied the ion channel behavior of the supported bilayer lipid membrane by scanning electrochemical microscopy （SCEM） in Tris （2,2’-bipyridine） ruthenium （II） solution. Perchlorate anion was used as presence of stimulus and ruthenium （II） complex cations as the probing ions of SECM measuring, the lipid membrane channel was open and exhibited distinct SECM positive feedback curve. The channel was in a closed state in the absence of perchlorate anions while reflected SECM negative feedback curve. The rates of electron transfer reaction at the lipid membranes surface were detected depended on the potential by SECM.In this section,n-Si（1 1 1） crystalline electrode was modified by carboxyl acid groups and sulfonic groups. The flat band potential (U_fb), relation between flat band potential and the carbon numbers to the modified samples and relation between photocurrent density and potential of the modified electrodes were studied. ATR–IR spectra and XPS analysis show that the organic compounds were connected to n-Si（1 1 1） wafer by Si-C bond. Calculation indicates that the surface modification ratio increased with the carbon number of organic groups decreased. Mott–Schottky plots gives the flat band potential of the samples to shift to negative positions with the carbon number decreased in both of the two different systems and the flat band potential of the sample with the group of -（CH₂）₃SO₃H reaches to -0.82V, which is more negative than reported, and the flat band potential of all the samples in this paper are more negative than the sample with methyl group. The photocurrent and photovoltage of the modifications are stable enough under solar illumination for a long time. Another work,by combining the self-assembly of initiator, ATRP and coordination to metal ions, Pb²⁺ and Cd²⁺, PAAM homopolymer brushes and the functional MMC brushes of PAAM were prepared on the surface of silicon wafers.The samples were confirmed by XPS and contact angle measurement. AFM was used to characterize the surface of silicon. these polymers should have interesting properties for many applications, such as electrochemical materials, optimized sensory, modified electrode and interface electrochemistry.更多还原