多壁碳纳米管-Nafion膜修饰铂电极的电化学性质

Electrochemical Properties of Multi-walled Carbon Nanotubes- Nafion Coated Platinum Electrode

使用多壁碳纳米管(MWCNTs)和Nafion溶液制备了多壁碳纳米管-Nafion膜修饰的铂电极。运用扫描电子显微镜(SEM)对多壁碳纳米管、Nafion膜、多壁碳纳米管-DMF膜和多壁碳纳米管-Nafion膜进行了形貌表征。通过电化学系统研究了铁氰化钾在多壁碳纳米管-Nafion膜修饰电极、多壁碳纳米管-DMF修饰电极以及未修饰铂电极的表面电化学行为。结果显示,多壁碳纳米管-Nafion膜修饰的电极对铁氰化钾有显著的电化学增强作用,于0.185 V处形成了一个尖锐的还原特征峰,比未修饰的铂电极还原峰增强近8.7倍;在0.231 V处形成了一个较强的氧化特征峰,比未修饰的铂电极氧化峰增强近2.7倍。由于多壁碳纳米管的比表面积大,利用其与Nafion修饰的电极能增强电子传输效率,使测定的峰电流增大,从而提高灵敏度,有助于检测低浓度物质。进一步研究发现,铁氰化钾在未修饰的铂电极表面反应为可逆反应,而在MWCNTsNafion膜修饰后的电极表面反应为不可逆反应。

The multi-walled carbon nanotubes- nafion film coated platinum electrode was prepared with multi-walled carbon nanotubes and nafion solution in the article. The structures of the multiwalled carbon nanotubes,nafion film,multi-walled carbon nanotubes- DMF film and multi-walled carbon nanotubes- nafion film were characterized by scanning electron microscopy（ SEM）. The electrochemical behaviors of potassium ferricyanide at multi-walled carbon nanotubes- nafion flim modified electrodes were studied and compared with those at multi-walled carbon nanotubes- DMF modified electrodes and unmodified platinum electrode by cyclic voltammetry（ CV）. The multi-walled carbon nanotubes- nafion film modified electrode exhibited a remarkable enhanced effect on the current response of potassium ferricyanide. A sharp reduction characteristic peak at 0. 185 V was observed,and the intensity of peak increased 8. 7 times as compared with that of unmodified platinum electrode.And the intensity of oxidizing characteristic peak at 0. 231 V increased 2. 7 times as compared with that of unmodified platinum electrode. The MWNTs＇ surface has a big area,therefore,it could be used to enhance electronic transmission efficiency and improve the sensitivity. The studies also showed that the surface reaction of potassium ferricyanide at unmodified electrode is reversible reaction,but not at multi-walled carbon nanotubes- nafion film modified electrode.