Whelk-like Helixes of Polypyrrole Synthesized by Electropolymerization


  • This work is financially supported by the Youth Science Research Foundation of Beijing University of Technology (Grant No. 00298), Beijing Natural Science Foundation (Grant No. 205001); and National 973 Program of China (Grant No. 2002CB211807). D.G.X. acknowledges the financial support from the Institute for Fuel Cell Innovation, National Research Council of Canada (NRC-IFCI), for his research as a visiting research professor at NRC-IFCI. We thank Prof. Ji Yuan (Beijing University of Technology, Institute of Solid and Microstructure) for her help with SEM analysis and Ms. Ye Xiaoyan (Tsinghua University, Department of Chemistry) for her help with XPS analysis. We also thank Dr. Ma Changqi (University of Ulm, Department of Organic Chemistry II, Germany) for helpful discussions. Supporting Information is available online from Wiley InterScience or from the author.


A whelk-like helix of polypyrrole was synthesized by an electropolymerization process. Its structure and properties were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry. The high-resolution SEM images clearly show the whorls around the polypyrrole whelk body; these whorls have ordered periodic nanostructures on their surface. XPS analysis indicates that the polypyrrole structure is highly doped with sodium dodecyl sulfate, the chosen dopant. A novel spiral growth mechanism is proposed. The whelk-like polypyrrole layer shows high thermal stability, superhydrophilicity, and strong electrocatalytic activity towards the oxidation of ascorbic acid.