Noncovalent grafting of poly(3-octylthiophene) at the edges of the graphene nanosheets.

Noncovalent functionalization of graphene was carried out via in-situ oxidative polymerization of poly(3-octylthiophene) (P3OT). First, graphene sheets were prepared by a modified Hummer's method and subsequently reduced with hydrazine monohydrate. The structure and morphology of the composites were investigated by using FTIR, XPS, EDX, TGA, HRTEM, FESEM and XRD measuments. The results obtained from spectroscopic studies confirm the reduction of graphite oxide to graphene. UV-Vis and photoluminescence spectroscopies were also used to prove the doping function of the graphene in the composites. Dispersion stability indicates the good mixing between graphene and the polymer due to pi-pi interaction between two components. Scanning electron microscopy results suggest that the graphene sheets were well dispersed in the polymer matrix. The UV-Vis spectra of graphene/P3OT composites show a red shift by a few nanometers, while the emission spectra show a small blue shift. However, the nanocomposites retained the photoluminescence property of as synthesized P3OT.