A versatile and cost-effective reduced graphene oxide-crosslinked polyurethane sponge for highly effective wastewater treatment

Abstract

Gradually deteriorating water quality caused by oil or chemical leakage and heavy metal wastewater discharge is becoming a global problem. To address this issue, a versatile absorbent material was designed and fabricated by coating reduced graphene oxide (rGO) on porous polyurethane (PU) sponges. Firstly, calcium carbonate nanoparticles (nano-CaCO₃) and graphene oxide (GO) were added during the preparation of the PU sponge. A PU sponge with nanosized porous framework was obtained after etching the nano-CaCO₃. After the reducing process, rGO was precisely coated on the prepared porous PU via crosslinking to obtain porous rGO-based PU sponge (porous PU@rGO). The physicochemical properties of the as-fabricated porous PU@rGO indicated that it was recyclable, hydrophobic and conductive. Batch experiments were carried out, and results suggested that porous PU@rGO has a widespread potential for applications in oil–water separation, the break-up of oil-in-water emulsions, as well as hazardous ion adsorption.