阳离子染料－蒙脱石化学修饰电极的电化学性质─—与Nafion膜化学修饰电极的比较

Electrochemical Properties of Cationic Dye-Clay Modified Electrode ──Comparison with Nafion Polymer Film Modified Electrode

用蒙脱石与Ｎａｆｉｏｎ制备了阳离子染料中性红化学修饰电极（ＣＭＥ）．两种ＣＭＥ在支持电解质溶液中有相似的循环伏安行为．蒙脱石ＣＭＥ的峰电流随膜厚增加而增加，而ＮａｆｉｏｎＣＭＥ的峰电流随膜厚增加有所降低．阳离子染料在蒙脱石膜内的扩散系数比在Ｎａｆｉｏｎ膜中的扩散系数大一个数量级．阴离子电活性物以及不同的制备方法对两种ＣＭＥ的电化学响应有不同的影响．两种ＣＭＥ在性质上的差异反映了两种膜的微结构与通透性等方面的差别．蒙脱石用作制备化学修饰电极的表面层材料有一定吸引力．

Cationic dye(Neutral Red)Chemically Modified Electrode (CME)were prepared with clay and Nafion.Both of them reveal similar cyclic voltammetric behavior in the supporting electrolyte.The peak current ofmontmorillonite CME increases with increase of the film thickness,however,the Nafion CME reduces some-what of its peak current value with increasing the film thickness.The diffusion coefficient of cationic dye inmontmorillonite film is about one order of magnitude larger than that of Nafion film.Anionic electroactivespecies and different preparation methods have different effects on electrochemical responses of two kinds ofCME.The difference in properties reflects the difference in microstructure and penetrability of two kinds offilms.Montmorillonite is a useful material for preparing chemically modified electrode surface.