Amphiphilic super-wetting membranes from direct immobilization of nanoparticles by in-situ polymerization and ionic cross-linking during phase inversion

Super-wetting membranes have recently attracted widespread attention for their promising application in oil/water separation. Generally, the preparation procedures of the super-wetting membranes are quite arduous, and it remains challenging to design a reasonable fabrication method. In this work, we present a facile method to prepare polyvinylidene fluoride (PVDF) based super-wetting membranes from direct immobilization of nanoparticles by in-situ polymerization and ionic cross-linking during phase inversion. The as-prepared membranes exhibited excellent amphiphilic properties, and had switchable wettability between super-oleophobic underwater and super-hydrophobic under oil. The modified PVDF membranes with such switchable wettability had high separating performance towards both surfactant-stabilized water-in-oil and oil-in-water emulsions under gravity and exhibited good durability and recyclability. This research not only provides a simple preparation method of amphiphilic super-wetting membranes, but also the unique performance of the membrane in water treatment.