碳纳米管/Nafion复合物修饰电极制备及性能研究

Study on preparation of carbon nanotubes/nafion complex modified electrode and its properties

运用一步电沉积法制备MWCNTs丝网印刷碳电极,再用滴涂法修饰Nafion制备了M WCNTs/Nafion丝网印刷电极。采用循环伏安法和阻抗分析法对功能化电极进行电化学表征,结果显示,功能化电极能够有效提高峰电流和降低电子转移阻抗值;通过拉曼光谱仪和场发射扫描电子显微镜对其表面进行形貌表征,结果证实MWCNTs被成功修饰在了电极表面。电化学行为研究表明峰电流与Pb^(2+)浓度呈较好线性关系,并求得线性回归方程为y=26. 598x-1. 6831,线性范围为0. 96～4. 8μmol/L,线性相关系数R2=0. 9563。采用三电极体系,在0. 2 mg/mL Pb^(2+)标液中做DPSV扫描显示修饰电极有良好的重现性和稳定性。最后,探究差分脉冲溶出伏安法测定皮皮虾中Pb^(2+)的含量与加标回收实验,测得各元素回收率在90%～120%之间。

MWCNTs screen printing carbon electrode was prepared by one-step electrodeposition,and then MWCNTs/Nafion modified screen printing electrode was prepared by the modification of Nafion through coating.The electrochemical characterization of functional electrode was carried out by cyclic voltammetry and impedance analysis.The results showed that the functional electrode could effectively increase peak current and reduce electron transfer impedance.The surface morphology was characterized by Raman spectrometer and field emission scanning electron microscope,and the results showed that MWCNTs were successfully modified on the electrode surface.Studies on the electrochemical behavior of plumbumion showed that peak current had a good linear relationship with Pb2+concentration in the range of 0.96-4.8μmol/L.The linear regression equation was y=26.598 x-1.6831 with the linear correlation coefficient of R2=0.9563.Using a three-electrode system,differential pulse voltammetry(DPV)was performed in 0.2 mg/m L Pb2+standard solution showing that the modified electrode had good reproducibility and stability.Finally,DPV was used to investigate the determination of Pb2+in Mantis Shrimp content and standard recovery experiment.The recoveries of each elements were between 90.0%-120.0%,which indicated the modified electrodes had good precision and accuracy.