High water permeance and ion rejection through F-graphene oxide membranes

Abstract

Graphene oxide (GO) membranes have attracted a great deal of attention due to their special two-dimensional (2D) structure and excellent ion sieving properties. However, GO membranes for high valence metal ion rejection still suffer from the limitation of low water permeance and low stability in wastewater treatment. In this study, we reported a kind of 2,4-diamino-6-(4-fluorophenyl)pyrimidine cross-linking graphene oxide (F-GO) membrane with larger interlayer spacing and F-functioned channels, which exhibited an excellent water permeance of ∼219.7 L m⁻² h⁻¹ bar⁻¹, which was 5.1 times higher than that of pristine GO membranes, while still maintained 99.9% ion rejection for wastewater treatment. Furthermore, the long-term stability of the F-GO membrane in nanofiltration performance was also experimentally obtained. Overall, our research demonstrates a simple way for achieving high permeances for the effective removal of high valence ions using GO-based membranes, and they may serve as the next promising materials for wastewater treatment.