Simultaneous synthesis of poly(2,5-dimethoxyaniline) silver nanoparticles and in poly(styrene sulfonic acid)

Silver nanoparticles were formed in situ along with poly(2,5-dimethoxyaniline) (PDMA) in an interconnected network matrix (reactor), comprising the electronic conductive polymer, PDMA, and a polyelectrolyte, poly(styrene sulfonic acid) (PSS), through the simultaneous reduction of Ag+ ions and polymerization of 2,5-dimethoxyaniline. In situ ultraviolet-visible spectroscopy showed that peaks corresponding to the plasmon resonance of silver nanoparticles at 411 nm and the polaronic transition of PDMA at 438 nm provided evidences for the simultaneous formation of silver nanoparticles and PDMA. Transmission electron microscopy and size distribution analysis revealed the presence of spherical silver nanoparticles with an average diameter of 12 nm in the composite. X-ray photoelectron spectroscopy showed that the amine units in PDMA changed to imine units upon the formation of silver nanoparticles. A comprehensive mechanism for the formation of the PDMA-PSS-Ag nanocomposite is proposed. A 10-fold increase in the conductivity was noticed for the PDMA-PSS-Ag nanocomposite (1 S/cm) in comparison with the PDMA-PSS composite (0.1 S/cm). (c) 2006 Wiley Periodicals, Inc.