Preparation and Characterization of Thin-Film Nanocomposite Membrane with High Flux and Antibacterial Performance for Forward Osmosis

In this work, thin-film nanocomposite (TFN) forward osmosis (FO) membranes have been prepared by electrospinning technology and interfacial polymerization technology. Scanning electron microscopy and Fourier transform infrared spectroscopy analysis confirmed that graphene oxide (GO) has been successfully added into polyamide (PA) selective layer. The reduced roughness of membrane's surface was verified by atomic force microscopy. Together with the hydrophilic/hydrophobic interpenetrating network composite nanofibers (HH-IPN-CNF) structure of the substrate, the incorporation of hydrophilic GO into selective layer of FO membrane also enhanced water permeability. The superior FO separation performance of the modified FO membrane was obtained under circumstance of 0.05 wt % GO with average water flux of 29.88 and 44.02 LMH in FO mode and pressure-retarded osmosis (PRO) mode, respectively. This most permeable modified FO membrane had a water flux about 50 and 40% higher than the pristine FO membrane with a negligible variation in reverse salt flux. The GO modifying also significantly enhanced the antibacterial property of the FO membrane. The existence of the GO effectively inhibited the growth of the biofilm formed by Escherichia coli on the surface of the FO membrane. This concept provides a simple efficient method to develop high-performance FO membranes.