Advanced Materials: TechConnect Briefs 2015Advanced Materials TechConnect Briefs 2015

Coatings, Surfaces & Membranes Chapter 8

Relationship between Morphology and Electrochemical Properties of Polyaniline in the Nanometer Regime

Y. Lee and H. Yoon
Chonnam National University, Korea

pp. 533 - 535

Keywords: polyaniline, polymer polymerization, nanostructure

Polyaniline (PANI) has found a wide range of applications due to its electrical properties, reversible redox behaviors and environmental stability. Here, we report the preparation of PANI nanostructures with three different aspect ratios, namely, nanospheres, nanorods, and nanofibers. A water-soluble polymer, polyvinyl alcohol is used to give a steric effect in the PANI chain growth which allows tailoring of the morphology of the resulting PANI nanostructures. We further examine what factors strongly affect the device performance when PANI nanostructures are used as the electrode-active materials for supercapacitors. The polymerization rate became slower in the presence of the stabilizer yielding PANI nanostructures with lower aspect ratios. Accordingly, it is believed that the stabilizer sterically restricts the directional fiber growth mechanism governing PANI chain growth in aqueous solution. The oxidation/protonation levels of the three nanostructures were also investigated. The nanofibers were found to have the most outstanding oxidation/protonation level accompanied by structural ordering. The intrinsic charge-transport ability of individual nanostructures strongly influenced the electrochemical properties of the electrodes.