Morphological and electrical characteristics of polyaniline nanofibers

Polyaniline nanofibers with an average diameter of <100 nm were synthesized from two different polymerization processes. They were fabricated either (a) via a template-tree procedure at the interface of a heterogeneous (biphasic) medium composed of an organic solvent (toluene or CCI4) containing the monomer (aniline) and an aqueous layer containing the oxidizing agent (ammonium peroxydisulfate, APS) and camphorsulfonic acid (HCSA) as the dopant or (b) in a homogeneous (monophasic) medium in which nanofiber growth is promoted by the presence of a small amount (<1% by wt.) of single-walled carbon nanotubes as an added polymerization “seed” template. UV/Vis spectra of the nanofibers were obtained from pressed pellets or solution-cast thin films on glass slides confirming the conducting (doped) state of polyaniline. The electrical properties of the as-synthesized nanofibers (press pellets) were obtained via the conventional four-probe technique. Linear voltage-current (V-I) characteristics were recorded providing an estimated value of the electrical conductivity. The morphology and average diameter of the obtained nanofibers were investigated by Scanning Electron Microscopy (SEM).