Hydrothermal reduced graphene oxide membranes for dyes removing

Graphene oxide (GO) has potential application in membrane separation owing to its extraordinary permeance. In this paper, the reduced graphene oxide (rGO) was synthesized by a green hydrothermal reduction method, and the rGO membranes was prepared on polyvinylidene fluoride (PVDF) supporting membranes by vacuum filtration. The interlayer structure of GO and the permeability of rGO membranes can be controlled by adjusting the reduction degree of GO through changing the hydrothermal reaction time. The disorder and defects of rGO nanosheets, the less oxygen-containing functional group and the enhanced hydrophobicity facilitate transport of water molecular in relatively smaller interlayer space owing to hydrothermal reduction. Compared with the GO membranes, the hydrothermally reduced rGO membranes showed a more excellent permeability without sacrificing rejection. The rejection of the prepared rGO membrane for Methyl blue, Congo red and Crystal violet all exceed 99%.