Electrode Processes Utilizing the Interlayer Space of Inorganic Molecular Aggregates a Reaction Zone

(1)研究了Ru(bpy)^2+_（bpy=2,2′-联吡啶）和Fe(CN)^3-_离子在粘土修饰电极上的氧化还原行为与溶液酸度的关系，发现随着酸度的增加，正离子Ru(bpy)^2+_的电极反应受到抑制，而阴离子Fe(CN)^3-_的电极反应得到促进。这些结果的解释是，酸度的增加导致粘土表面质子化的增加，导致带正电的电极表面与反应物质之间的静电相互作用增强。本研究首次证明了电极表面的带电状态在粘土修饰电极的电化学反应中起着重要的作用。(2)将苯胺掺入粘土层间空间，进行电化学聚合。发现电聚合进行得非常缓慢，需要十多个小时才能完成反应，这表明粘土层间空间的电解反应速度非常慢。(3)在粘土层间空间中掺入微晶Tio_2作为光催化剂，对不同分子大小的普通羧酸进行了光分解。研究发现，粒径小于粘土间隙的羧酸可以掺入粘土层间空间进行反应，而粒径较大的羧酸则不能掺入粘土层间空间，反应活性较低。(4)采用不同孔径的沸石制备了沸石修饰电极，研究了Fe^<2+>离子在电极上的氧化还原行为。研究发现，如果所用沸石的孔径大于水合Fe^<2+>离子和所用电解质阳离子的离子直径，则掺入的Fe^<2+>离子可以在强酸性溶液中进行氧化还原反应。

(1) Redox dehaviors of Ru(bpy)^2+_(bpy=2,2 '-bipyridine) and Fe(CN)^3-_ ions at a clay-modified electrode were investigated as a function of acidity of solution, and it was foound that the electrode reaction of cationic species, Ru(bpy)^2+_, is suppressed but that of anionic species, Fe(CN)^3-_, is promoted with an increase in acidity. These results are explained from the viewpoints that the increase in acidity results in an increase in protonation of the clay surface, causing the enhancement of electrostatic interaction between the positively charged electrode surface and the reaction species. In the present study, it has firstly been shown that the charged state of electrode surface plays an important role in electrochemical reactions at clay-modified electrodes.(2) Aniline was incorporated in the interlayer space of clay and then polymerized electrochemically. The electropolymerization was found to proceed so slowly that it took more than ten hours to complete the reaction, giving the suggestion that the rate of electrolytic reactions in the interlayer space of clay is very slow.(3) Microcrystalline Tio_2 incorporated in the interlayer space of clay was used as a photocatalyst for photodecomposition of normal carboxylic acids with different molecular size. It was found that the carboxylic acids the size of which are smsller than the clearance space of the clay can be incorporated in the interlayer space of clay to undergo the reactions, while the larger carboxylic acids can not be incorporated in the interlayer space of clay exhibiting low reactivities.(4) Zeolite-modified electrodes were prepared by using zeolited with different pore size, and redox behaviors of Fe^<2+> ions at the electrodes were investigated. It was found that the redox reactions of the incorporated Fe^<2+> ions can thke place in strongly acidic solutions if the pore size of the zeolite used is larger than the ionic diameters of both hydrated Fe^<2+> ions and electrolyte cations used.