A facile graphene oxide modified approach towards membrane with prominent improved permeability and antifouling performance

Abstract

The superior hydrophilicity of graphene oxide (GO) makes it a promising candidate for improving the permeability and antifouling performance of membranes used for feed water pretreatment in desalination systems. However, the uncontrollable assembly structures of GO laminates on membrane surface restrict the full exertion of its hydrophilicity. In this study, a layer-by-layer self-assembled GO-based nanocomposite membrane with adjustable interlayer spacing and assembly layers was facilely fabricated by alternately depositing GO and (3-Aminopropyl) triethoxyilane modified silicon dioxide (SiO2@APTES) on membrane surface via electrostatic interaction. The fully exerted hydrophilicity of GO and well-maintained membrane pore structures facilitated the adsorption and penetration of water molecules, meanwhile, the hydration layer and electronegativity of GO effectively inhibited the adhesion of foulant. Thus, monolayer GO/SiO2@APTES/GO endowed P-(G/S/G)1 membrane with more than 10-fold water flux (560.2 L m−2 h−1) than pure PVDF membrane (55.4 L m−2 h−1) without sacrificing selectivity; and the antifouling performance was improved by nearly 50%. Moreover, the nanocomposite membrane presented robust structural stability after physicochemical cleaning. Overall, the nanocomposite membrane affords a novel facile way to fully exert the hydrophilicity of GO to improve permeability and antifouling performance, and is expected to provide an important guarantee for efficient operation of desalination system.