Electrochemical Characterization Of Multi-Walled Carbon Nanotubes/Polyvinyl Alcohol Coated Electrodes For Biological Applications

A multi-walled carbon nanotubes (MWCNTs)/polyvinyl alcohol (PVA) composite coating modified electrode with excellent microstructural homogeneity was produced from aqueous suspensions using electrophoretic deposition (EPD). The zeta-potential of MWCNTs/PVA composite particles near electrodes plays a vital importance on the process of electrophoretic deposition, for the decrease of zeta-potentials leads to particle coagulation. The effect of main EPD parameters including applied voltage and deposition time on the deposit yield as well as the electrochemical performance of modified electrode was investigated. At the optimal EPD condition (voltage of 35v and deposition time of 2.5 min). MWCNTs/PVA modified electrodes showed well-defined voltammetric responses for the Fe (CN) (4-)(6)/ Fe (CN) (3-)(6)redox system in phosphate buffer solution (PBS). Both anodic and cathodic peak currents of modified electrode exceed those of bare copper electrode, which means modified electrode delivers higher charge. The peak currents depended linearly on the square root of the scan rate in the range of 10mv/s-100mv/s, suggesting diffusion-control and fast electron conduction within MWCNTs/PVA composite coating.