A promising scalable route to construct GO-based laminate membranes for antifouling ultrafiltration

Graphene oxide (GO) laminate membranes have been deemed as promising membrane materials for a variety of applications, but they suffer from poor stability in solvents and difficulty in large-scale preparation. Herein, a scalable method was used to fabricate GO-based laminate membranes in a large area by dip-coating a GO/polyvinyl alcohol (PVA) mixed dispersion on a commercial filter paper, followed by borate crosslinking for enhancing the stability. Micromorphological investigation demonstrated that an even and continuous GO/PVA layer was constructed on a filter paper, which exhibited obviously laminated assembly architecture. Membrane testing confirmed that the water flux and molecular weight cut-off (MWCO) of the obtained GO/PVA composite membrane could be facilely tuned by changing the content of GO or PVA in the mixed dispersion. Moreover, multiple recycling tests demonstrated that about 86% of the water flux of the GO/PVA composite membrane was recovered by water cleaning even after 4 cycles, exhibiting good anti-protein-fouling performance. Additionally, the composite membrane also showed good tolerance to acidic and alkaline solutions, organic dye separation capability and excellent antibacterial property. This research affirmed that dip-coating a GO/PVA mixed dispersion is a potential way for the large-scale preparation of GO-based laminate membranes and broadening the prospects of GO-based laminate membranes in various separation fields.