Conducting Polymer Microstructures

Nano/micrometer-sized materials, due to their unique properties different from bulk materials, have many potential applications in microelectronics, micromachines, microchips and catalysis. Microstructured conductive polymer materials not only have the inherent trait of conducting polymers, but also the peculiar functions of microminiatures, which make them irreplaceable for applications in many aspects. In this paper, polypyrrole microstructures can be synthesized by direct electrochemical oxidation of pyrrole in the aqueous solution of β-naphthalenesulfonic acid, camphorsulfonic acid and polystyrenesulfonic acid. The formation mechanism of microstructures was investigated and the microstructures were applied to fabricating biosensors. Furthermore, polypyrene microsheets with crystalline structure also have been synthesized in the medium of boron trifluoride diethyl etherate.1. Polypyrrole microstructures with morphologies like bowls, cups, tubules and spheres have been electrosynthesized by direct oxidation of pyrrole in the aqueous medium of β-naphthalenesulfonic acid,camphorsulfonic acid or polystyrenesulfonic acid. It is the first time that such microstructures were achieved through a template-free approach. The microstructures stand upright on the surface of the electrodes in a high density, and they can be stripped from electrode into free standing state. The results of Raman and infrared spectra indicated they were made of conductive polypyrrole. 2. The micron-sized gas bubbles assembled on the surface of working electrode worked as the template for the growth of PPy microstructures. During electrolysis, gas bubbles (hydrogen or oxygen) were released and dispersed in the solution containing anion surfactants. Under the function of electric field, the gas bubbles near the anode zone were assembled on the surface of working electrode. The polymerization of pyrrole around the gas bubbles resulted in the formation of the microstructures.3. Based on the patterned Si electrode, linear arranged microstructures can be synthesized due to the space-limited assembly of gas bubbles on the electrode surface. Based on polypyrrole microstructures film, glucose biosensor with high sensitivity was fabricated. 4. Crystalline polypyrene microsheets were electrosynthesized in the medium of boron trifluoride diethyl etherate for the first time. Polypyrene sheets were grown vertically to the surfaces of the nucleation particles, and changing the electrochemical conditions could modify the hydrophobicity of the polypyrene film. Furthermore, the fluorescence of polypyrene is much stronger and more unitary than that of pyrene.