One-pot preparation of smooth and water permeable nanosized graphene oxide/PVDF composite membranes via diamine-mediated interactions

Abstract We report poly(vinylidene fluoride) (PVDF) composite membranes incorporating graphene oxide (GO) nanosheets and a diamine. The diamine modifies GO and induces intermolecular interactions and/or cross-linkings with PVDF, yielding smooth, mechanically robust membranes. Despite reduced porosity, the membranes show enhanced water flux and ion rejection. Notably, smaller GO nanosheets lead to excellent performance, contrary to conventional expectations, due to hydrophilic nanochannels and controlled densification of the PVDF matrix.