Covalent assembly of 3D graphene/polypyrrole foams for oil spill cleanup

Abstract

Functionalized graphene oxide (KGO) sheets were covalently assembled with pyrrole and reduced to form a 3D foam structure via a multistep route through the hydrolytic condensation (cross-linking), polymerization reactions and hydrothermal reduction of graphene oxide (GO). The formed graphene/polypyrrole foam and its structures were analyzed using Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The specific surface area and the total pore volume of the samples were measured using N₂ adsorption. The graphene composite foams have a special 3D structure, with a wide range of macropores (from sub-μm to several hundred μm) and mesopores within. Due to the intrinsic covalent bonding between graphene sheets and the special 3D structure, not only were the sorption capacities of the graphene/polypyrrole foams determined to be very high for oil (>100 g g⁻¹) and solvent, but also the sorption rate was very high.