One-pot synthesis and electrical characterization of monodisperse solid polyaniline sub-microspheres

Abstract

Monodisperse solid polyaniline (PANI) sub-microspheres were synthesized in nonpolar solvent toluene using chloroaurate acid (HAuCl4) as the oxidant and cetyltrimethylammonium bromide (CTAB) as the phase-transfer reagent. The reduction of chloroaurate acid is accompanied by oxidative polymerization of aniline, leading to the formation of uniform solid PANI sub-microspheres covered with a breadcrumb-like structure, with a diameter of about 400 nm and incorporated with gold nanoparticle aggregates. The resulting solid PANI sub-microspheres were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, UV-visible spectroscopy, and X-ray diffraction (XRD). The formation mechanism of the solid spheres is also discussed. The current-voltage (I-V) characteristics of the PANI submicrospheres were measured, which indicate the conductivity of the samples is related to the degree of doping which is pressure dependent. © 2011 American Scientific Publishers.