Preparation of hierarchical polyaniline nanotubes based on self-assembly and its electrochemical capacitance

This article reports the preparation and self-assembly of polyaniline (PANI) nanotubes, which were chemically synthesized by using in situ doping polymerization in the presence of ammonium persulfate (APS; (NH4)S2O8) as the oxidant without the use of an external template. The synthesized hierarchically nanotubes with a shape of a single nanotube with a length of 0.6 to 0.8?mu m and an average with of 100?nm assembled from nanoparticles. The effects of the [salicylic acid]/[aniline] ratio on the size and capacitance of PANI nanotubes were studied. The specific capacitance behavior of the PANI nanotubes was also investigated by using cyclic voltammogram and galvanostatic chargedischarge tests. A maximum discharge-specific capacitance of 422.5?F/g could be achieved, suggesting its potential application in electrode material for electrochemical capacitors. Copyright (c) 2011 John Wiley & Sons, Ltd.