Ultrasonic-microwave assisted synthesis of stable reduced graphene oxide modified melamine foam with superhydrophobicity and high oil adsorption capacities

We herein report the fabrication of recyclable, stable and cost-effective superhydrophobic reduced graphene oxide modified melamine foam (RGMF) through ultrasonic-microwave synergistic method for the first time. In the synthesis process, ultrasonic and microwave irradiation not only shortened the reduction time of graphene oxide (GO) with the existence of reducing agent, but also considerably enhanced the firmness of reduced graphene oxide (rGO) anchored onto the melamine foam (MF). The structure and property of the obtained RGMF were characterized by XRD, Raman, SEM and contact angle measurements. The results showed that the skeletons of MF were completely covered with rGO layers which were compact and full of wrinkles. The as-prepared RGMF was superhydrophobic without further modification. Besides, the RGMF showed excellent selective adsorption capacity of various oils and organic solvents from water. The maximum oil adsorption capacity was 112 times of the weight of the initial MF, and the adsorption capacity of the RGMF did not deteriorate after it was reused 20 times. More importantly, the RGMF showed good stability against cavitation erosion and corrosion liquids. All these features made the as-prepared material an ideal candidate for removal and collection of oils and organic solvents from water. (C) 2016 Elsevier B.V. All rights reserved.