Electrical Tunable PVDF/Graphene Membrane for Controlled Molecule Separation

Though membrane separation has been an efficient and energy-saving technique for dealing with wasted mixed chemical matter, the concomitant environmental pollution has become a big issue in the development of the membrane field. Consequently, use of an active-responsive smart membrane appears to be a new trend for membrane development in the coming future, which shows great potential to deal with the obstacles. Here, we demonstrate the preparation of a smart electric-responsive membrane, PVDF/graphene composite membrane, in which the graphene induces self-assembly of PVDF chains, showing a highly β phase and thus a unique piezoelectric property. The resultant nanochannels in the membrane could be reversibly adjusted by electric driving, resulting in tailored alcohol selectivity on the single membrane. The membrane was utilized to challenge the dehydration of a MeOH/water mixture, which offered a >99.5 rejection to MeOH molecules with high water flux, achieving a precise molecule separation performance. Overall, the novel active membrane separation process proposed in this work opens the gates toward the development of a novel generation of an active smart membrane, which is imperative for the future of a sustainable society.