碳纳米管电极上的电化学行为分析

Analysis of electrochemical behaviors on the carbon nanotube electrode

用化学方法对碳纳米管进行表面处理 ,用红外谱对处理后的碳纳米管进行表征 ,处理后的碳纳米管表面出现了活性功能团羧基。用这些碳纳米管制成电极 ,对Cd离子在硫酸钠中的电化学行为进行了分析。结果表明 ,从碳纳米管电极上可以观察到很好的、准可逆循环伏安图 ;在扫描速度为 10 0mV·s- 1时 ,氧化还原峰电位分别出现在 - 0 .6 5V和 - 0 .95V对照饱和甘汞电极(SCE)。峰电流与扫描速度的平方根成良好的线性关系 ,说明反应过程是由镉离子的扩散控制的。由循环伏安图相关的电位与扫描速度关系 ,我们导出了电子转移动力学速度参数。由于碳纳米管电极有很好的电化学活性和可重复性 。

The carbon nanotubes, treated by chemical method, are characterized by FTIR spectra, show active carboxyl acid groups on them. We maked the treated nanotubes as electroanaly tical electrode to investigate the electrochemical behaviors of Cd ion in sodium sulfate. A well defined quasi reversible cyclic voltammograms were presented and the redox peaks appeared at -0.65 V and-0.95 V vs SCE, respectively, at the scan rate 100 mV·s -1 . The peak currents depend linearly on the square root of the scan rate, which indicates that the reactions are controlled by the Cd diffusion. The electron transfer rate constant is evaluated from the dependence of the voltammograms on the potential scan rate. As the activity and reproducibility, the carbon nanotubes can become a new electrode material.