Conductive Graphene–Melamine Sponge Prepared via Microwave Irradiation

A conductive graphene-melamine sponge (MS) prepared via microwave irradiation is reported in this paper. Graphene oxide supported on the MS was prereduced first at 100 °C and then further reduced in a household microwave oven at over 1000 °C. It was surprising to find that graphene oxide on the MS was reduced perfectly while the three-dimensional structure of the MS was kept well after high-temperature reduction via microwave irradiation. Slight pyrolysis of MS was also found during 5 s microwave irradiation, resulting in nitrogen generation from the pyrolysis of the MS being doped into graphene, which could benefit the electric conductivity of the prepared graphene-MS. The electric conductivity of the prepared graphene-MS is about 0.12-1.0 S/m because of the high reduction degree of graphene oxide and nitrogen doping. On the other hand, different from the pure MS, the newly developed conductive graphene-MS possesses superhydrophobic and superoleophilic properties. Overall, the newly developed conductive graphene-MS contained 94.3 wt % MS and 5.7 wt % N-doped graphene and is a cost-effective material with good elasticity, high conductivity, superhydrophobicity, and superoleophilicity.