Synthesis of three-dimensional graphene oxide foam for the removal of heavy metal ions

Three-dimensional free-standing graphene oxide foam (GOF) was explored as an exceptionally absorbent for the removal of heavy metal ions. GOF was prepared by direct oxidation of graphene foam (GF), and the GF was synthesized by microwave plasma chemical vapor deposition. The GOF processed a very high surface area (578.4 m2/g) and abundant oxygen functional groups with a rather low C/O ratio of 0.65. Evaluation of its adsorption capacity for the removal of heavy metal ions demonstrated that GOF had superior adsorption ability and good recyclability towards a wide range of metals ions, such as Zn2+, Fe3+, Pb2+, and Cd2+.