Conducting polymer micro-tubules hosting electroactive species without guest modification

A hollow micro-tubule structure comprised of the conducting polymer, PEDOT, was manufactured by the electrochemical polymerization of EDOT into a template membrane containing 1.2 μm pores. The tubules formed were then capped with a conducting PEDOT/PSS aqueous dispersion. In order to assist in effective capping, a piece of a PC membrane containing 0.05 μm pores was attached to the capping film of the aqueous dispersion. The cap was then reinforced with PEDOT via the electrochemical polymerization of EDOT in order to make it insoluble in aqueous solutions. The cavity of this micro-cylinder structure worked as a container retaining water-soluble electroactive materials and played the role as a current collector for the electrochemical reaction of the species retained inside. In this study, K3Fe(CN)6 was used as the probe material stored in the cylinders. The current collector exhibited a fine current response due to the redox reaction of the interior species. These results show that guest materials can be stored in this capped cylinder structure without the problems associated with the use of organic solvents during the manufacturing processes. Moreover, the most important part of the whole process can be monitored using simple electrochemical methods.