Ultrahigh permeance of a chemical cross-linked graphene oxide nanofiltration membrane enhanced by cation-π interaction.

Cross-linking with large flexible molecules is a common method to improve the stability and control the interlayer spacing of graphene oxide (GO) membranes, but it still suffers from the limitation of low water flux. Herein, a novel high flux GO membrane was fabricated using a pressure-assisted filtration method, which involved a synergistic chemical cross-linking of divalent magnesium ions and 1,6-hexanediamine (HDA) on a polyethersulfone (PES) support. The membrane cross-linked with magnesium ions and HDA (GO ) exhibited a high water flux up to 144 L m h bar, about 7 times more than that of cross-linked GO membranes without adding magnesium ions (GO), while keeping excellent rejection performance.