Porous reduced graphene oxide/phenolic nanomesh membranes with ternary channels for ultrafast water purification

Graphene and its derivatives are attracting substantial interest in constructing laminated separation membranes for water purification. However, the long and tortuous interlayer pathways are unconducive to achieve ultrafast water permeation. Herein, we present a facile approach for the preparation of graphene-based membranes with shorter and straighter water pathways. Porous reduced graphene oxide (rGO) nanosheets are mixed with phenolic/polyether nanosheets, followed by vacuum filtration to form laminated structures and acid treatment to remove polyether. The obtained porous rGO/phenolic nanomesh membranes are endowed with ternary channels for water to permeate comprising the 30-60 nm pores of rGO nanosheets, the 9 nm mesopores of phenolic nanomeshes, and the sub-nanometer interlayer nanochannels. Moreover, the hydroxyl-containing phenolic nanomeshes can polymerize, enabling good hydrophilicity and tight structures of the membranes. Such membranes exhibit ultrafast water permeation while remaining high rejections. This work demonstrates a simple and efficient route to fabricate high-performance separation membranes by using two kinds of two-dimensional porous nanomaterials.