Air-dried graphene-based sponge for Water/oil separation and strain sensing

An environmental-friendly, cost-effective and mild approach to prepare graphene-based sponge (GS) by in situ reduction-assembly of graphene sheets on the skeletons of melamine sponge was reported. The fabrication process is facile and no freeze-drying process is required. The structures of the GS were characterized by Raman spectra, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The hydrophobic and oleophilic GS exhibited high absorption capacities for organic liquids and excellent recyclability. Moreover, the electrical conductance of the GS is strain-sensitive, which changes in proportional with compressive strain. These significant performances make the GS candidate for potential applications in water/oil separation and strain sensing.