Graphene oxide quantum dots embedded polysulfone membranes with enhanced hydrophilicity, permeability and antifouling performance

Abstract

Graphene oxide (GO) has been demonstrated to be an effective hydrophilic nanofiller to modify the polymeric membranes when forming a mixed matrix structure. GO quantum dots (QDs) are promising candidates to fully exert the rich oxygen containing functional groups due to their unique size induced edge effects. In this work, GO QDs modified polysulfone (PSF) ultrafiltration (UF) membranes were prepared by phase inversion method with various GO QDs loadings (0.1–0.5 wt.%). A proper amount of GO QDs addition led to a more porous and hydrophilic membrane structure. With 0.3 wt.% GO QDs, the membranes showed a 60% increase in permeability (130.54 vs . 82.52 LMH bar–1 ). The pristine PSF membranes had a complete cutoff of bovine serum albumin molecules and it was well maintained with GO QDs incorporated. The membranes with 0.5 wt.% GO QDs exhibited the highest flux recovery ratio of 89.7% and the lowest irreversible fouling of 10.3% (54.5% and 33.3% for the pristine PSF membranes). Our results proved that GO QDs can function as effective nanofillers to enhance the hydrophilicity, permeability and antifouling performance of PSF UF membranes.