Electrochemical synthesis and properties of conical polypyrrole structures

Networks of conical polypyrrole structures have been deposited by the electrochemical oxidative polymerization of pyrrole in aqueous solutions containing NaClO4 and polymeric or anionic surfactants, such as PVP and SDS. The influence of polymerization conditions, such as deposition potential, time of polymerization, monomer concentration, supporting electrolyte, and surfactant, on the morphology, size, and aspect ratio of conical structures were systematically investigated. A plausible formation mechanism of the conical polypyrrole structure formation is discussed. The capacitance properties of thin films of networks of conical polypyrrole structures were determined. This material shows typical pseudocapacitive behavior with a relatively high specific capacitance of 375 F g(-1) and good electrochemical stability. This capacitance value is considerably higher than that of polypyrrole films deposited under typical electrochemical conditions. The high capacitance and good stability is promising for the application of conical polypyrrole structures in microsupercapacitor devices. (C) 2017 Elsevier Ltd. All rights reserved.