Rayleigh scattering by graphene-oxide in syndiotactic polystyrene aerogels

Robust monolithic aerogels based on syndiotactic polystyrene (s-PS) and graphene oxide (GO), and exhibiting high surface areas (240–290 m2/g) and low density (0.02–0.2 g/cm3), are presented. These aerogels are obtained by supercritical carbon dioxide extraction of s-PS/GO gels, which were prepared by s-PS dissolution in GO dispersions in suitable organic solvents. In contrast to other GO-based aerogels, the s-PS/GO aerogels are blue, not black. This blue color is due to Rayleigh scattering by isolated particles of reduced graphene oxide, whose thickness is much smaller than the wavelength of the light. The s-PS/GO aerogels exhibit the functionalities of the nanoporous-crystalline δ form of the polymer and of reduced and structurally uncorrelated GO layers and maintain the ductility of pure polymer aerogels. Uses can be anticipated as supported GO-based catalyst or “masterbatches” for GO rich nanocomposites.