In situ synthesis and characterization of conductive polypyrrole/graphene composites with improved solubility and conductivity

High conductivity and solubility of polypyrrole (PPy)/graphene composites has been successfully synthesized by in situ chemical oxidation polymerization using various concentrations of cationic polyelectrolyte poly(styrenesulfonate) (PSS) and ammonium peroxodisulfate (APS). Raman spectroscopy, FTIR, Raman, EPR and FESEM were used to characterize their structure and morphology. These FESEM images show that the fabricated PPy/graphene composites are core-shell structure. The results of Raman spectrum, FTIR and UV-Vis indicate the synthesized PPy/graphene composites are in the doped state. The conductivities of PPy/graphene composites synthesized with the weight ratio of PSS/pyrrole monomer at 0.5 are about five times of magnitude higher than that of PPy/graphene composites without PSS. These results are perhaps due to the part of cationic electrolyte served as a dopant can be incorporated to the PPy structure to improve the conductivity of fabricated PPy/graphene composites. (C) 2012 Elsevier B.V. All rights reserved.