The Determination of the Charge-Transfer Rate at Ultra-Micro Film-Coated Electrodes by Using Super Fast Pulse Voltammetry

本文建立了用超快脉冲和扫描伏安法（SFV）测定超微薄膜涂层电极上电荷转移速率的方法，并对这些电极的使用特点进行了表征。在SFV中使用微电极的优点是消除了由于极低的电池电流引起的iR下降效应，提高了法拉第/非法拉第比值。由于电双层的充电电流大大减少，法拉第响应。因此，在微电极处使用SFV，其中可以获得高达约10^5Vs^的电位扫描速率<-1>和高达约1秒的电位步进速率，可以直接且可靠地检测快速电化学动力学，而用常规尺寸的电极很难或不可能确定该动力学。本文成功地测定了金属配合物（Mo（CN）^&lt;4-/3-&gt;_，W（CN）^&lt;4-/3-&gt;_，Os（CN）^&lt;4-/3-&gt;_等）的非均相电子转移速率常数。我们研究了聚合物涂层电极上的电极反应的动力学和热力学，其中上述多价阴离子络合物被静电限制在电极表面的阳离子聚合物膜中。在电活性电聚合膜涂层电极的电荷传输过程的动力学检查也已进行SFV，这被证明是有用的，如上所述。在这项研究中，有许多有趣的发展，试图解开聚合物涂层电极上的电荷传输过程。这些进展开辟了全新的研究领域，将电化学、高分子化学、有机化学、无机化学、生物化学、物理学等现代方面联合收割机结合起来。

The purpose of the present work is to establish the determination procedures of the charge-transfer rate at ultra-micro film-coated electrodes by using super fast pulse and sweep voltammetries (SFV) and to characterize the features of the use of these electrodes.The advantageous features of the use of microelectrodes in SFV are the elimination of iR drop effect due to very low cell current and the enhanced ratios of faradaic/non-faradaic response due to much diminished charging currents of electrical double layer. Thus, using SFV at microelectrodes, where scan rates of potential up to ca 10^5Vs^<-1>and step rates of potential up to ca 1 sec are attainable, it has become possible to examine straightforwards and reliably fast electrochemical kinetics, the determination of which was very difficult or impossible with a conventionally sized electrode. We here succeeded in the determination of the heterogeneous electron-transfer rate constants of metal complexes (Mo(CN)^<4-/3->_ , W(CN)^<4-/3->_ , Os(CN)^<4-/3->_ etc.). We have studied the kinetics and thermodynamics of the electrode reactions at polymer-coated electrodes where the above-mentioned multi-valent anionic complexes are confined electrostatically in cationic polymer films on electrode surfaces. A kinetic examination of the charge-transport processes at electroactive electropolymerized films-coated electrodes has also been conducted by SFV, which proved to be useful as described above.In this research, there have been many interesting developments in attempting to unravel the charge-transfer processes on polymer-coated electrodes. These advances have opened up whole new areas of investigation which combine modern aspects of electrochemistry, polymer chemistry, organic chemistry, inorganic chemistry, biochemistry, physics, etc.