Facile synthesis of silver-polypyrrole nanocomposites: Use of ionic liquid as solvent and template

Abstract

In this study we show a facile method to synthesize nanocomposites of PPY and silver from the direct oxidation of pyrrole by silver cations from silver bis(trifluoromethanesulfonyl)imide (AgTf2N), using 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMImTf2N) as solvent and template to the hybrid material formation. Some synthesis parameters, such as initial concentration of the oxidant agent (C) and oxidant-to-monomer molar ratio (K) were varied in order to evaluate their influence on the final product. The black powders obtained, according to the characterization results, contain doped polypyrrole and silver nanoparticles amounts ranged from 26 to 36 wt%, depending on the C and K parameters utilized in the syntheses. The measured electrical conductivity values of the samples were in the order of 10−2 S cm−1, which classify the hybrid materials as semiconductor. By adding the HTf2N acid to the synthesis, a sample with more elevated electrical conductivity (0.12 S cm−1) was obtained, caused by the higher protonation degree of the oxidized units in the polymer.