Nanotechnology-the key to unlocking the intrinsic properties of inherently conducting polymers

Full text: Currently the properties of inherently conducting polymers (ICPs) such as polypyrroles, polythiophenes and polyanilines at the macroscopic level is limited by our ability to unlock the inherent electronic and electrochemical properties they possess at the nanodimension. It is known that the macroscopic structures consist of highly conducting nanodimensional islands separated by a sea of less conducting material. It is also known that incredibly fast and discrete electrochemical switching can be obtained if nanowire ICP electrodes are used instead of larger structures. In our recent work several approaches for the synthesis and fabrication of controlled nanodimensional structures based on inherently conducting polymers have been investigated. The simplest involves chemical oxidation of monomer in an inverse microemulsion to produce polyaniline nanoparticles. The second approach involves use of a flow-through electrolytic method which enables production of nanoparticles of tightly controlled dimensions. Conducting polymer nanostructures have also been produced in our laboratories using an inverse synthetic opal approach wherein ICPs are synthesized within the interstitial volume of ordered nanoparticles. In a different strategy we have utilized the unusual properties of carbon nanotubes (high strength and conductivity) to produce ICP nanostructures. This has been achieved by using water soluble conducting polymer as a dispersant prior to making CNT structures or by individually coating arrays (forests) of aligned carbon nanotubes. The former approach has been used to produce CNT structures with high charge storage capabilities while the latter has presented a convenient route to ICP based biosensor surfaces with enhanced performance characteristics. Each of the above approaches to development of ICP nanocomponents and the properties of these unique structures will be discussed here