Sulfonated Polyaniline Nanostructures Synthesized via Rapid Initiated Copolymerization with Controllable Morphology, Size, and Electrical Properties

Abstract

Sulfonated polyaniline (SPANi), a self-doped conjugated polymer, has received great interest in recent years; however, controlling its shape, size, and conductivity at the nanoscale remains a significant challenge. Here, we report an initiator-assisted route to SPANi nanostructures by rapidly copolymerizing o-aminobenzenesulfonic acid with aniline or its derivatives in the presence of a catalytic amount of the initiator–aniline dimer. UV–vis, FT-IR, and XRD spectra reveal that the chemical compositions of the SPANi nanostructures are similar to that of conventional SPANi possessing an agglomerated morphology. By regulating the comonomer molar ratios, the aniline derivatives used and the acidic media employed, the morphology of the SPANi changes from 1-D nanofibers, nanosticks, nanothorns, and nanorods to 2-D nanoplates and 3-D porous nanospheres. The length and aspect ratio of the SPANi nanofibers can reach values up to 4.5 μm and 60, respectively. These SPANi nanostructures are readily processable in bot...