刚果红功能化水溶性碳纳米管膜电极的制备及在电化学传感器中的应用

Preparation of Congo Red-Functionalized Water-soluble Multi-walled Carbon Nanotubes Film at Glassy Carbon Electrode and Its Applications as Electrochemical Sensor

基于刚果红（CR）表面修饰多壁碳纳米管（MWNTs）在干燥时所具有的良好成膜性能，在玻碳电极表面制备了一种水溶性MWNTs（MWNTs-CR）膜，用扫描电镜（SEM）、傅立叶红外光谱（FTIR）和交流阻抗谱（EIS）对其进行了表征。结果表明，MWNTs-CR能在电极表面形成一层致密、均匀含有大量纳米级微孔的纳米结构薄膜。和裸玻碳电极相比，MWNTs-CR膜修饰电极能极大的增强雌酮和羟甲香豆素的电化学响应。在体系中加入表面活性剂后，其电化学响应能得到进一步的提高。羟甲香豆素的浓度在8．0×10^-8～4．0×10^-6mol／L范围内，其氧化峰电流与浓度呈现出良好的线性关系。在开路条件下富300s后，HMC的检出限为2．0×10^-8mol／L。实验证明水溶性MWNTs膜是构建碳纳米管电化学传感器的理想材料。

A Congo red （CR）-functionalized multi-walled carbon nanotubes （MWNTs-CR） film modified glassy carbon electrode （GCE） was prepared, based on the unique property of Strong rebundling when dried The prepared films were characterized by scanning electronmicroscopy （SEM）, Fourier transform infrared spectroscopy （FTIR） and electrochemical impedance spectroscopy （EIS）. The results showed that water-soluble MWNTs formed uniform films with porous network structures of nanosizes on the electrode surface. Compared with bare GCE, the electrochemical responses of estrone and hymecromone at MWNTs-CR film modified GCE were greatly enhanced, which were further amplified by the addition of trace cetyltrimethylammonium bromide （CTMAB） in solution. In the range of 8.0 ×10^-8 -4.0×10^-6 mol/L, the oxidation peak current was linear with hymecromone concentration and a low detection limit of 2.0×10^-8 mol/L was obtained for 300 s accumulation at open circuit. The enhanced responses of estrone and hymecromone at the film demonstrated that the water-soluble MWNTs were the ideal materials for constructing MWNTs-based electrochemical sensing films.