Ag nanoparticles decorated PVA-co-PE nanofiber-based membrane with antifouling surface for highly efficient inactivation and interception of bacteria

Microfiltration membrane with anti-biofouling surface is of high importance for improving the service performance of membrane system in water treatment owing to its excellent bacteria rejection behavior. Antibacterial property is effective to enhance the anti-biofouling performance of membrane. In this work, Ag NPs were decorated on the surface of Poly(vinyl alcohol-co-ethylene) nanofibrous membrane through charge adsorption by the PDA/PEI layer on nanofiber surface. The morphology and chemical structure analysis show that the spherical Ag NPs are successfully immobilized on the nanofiber surface uniformly. The membrane present distinct rejection efficiency of pigment nanoparticles with considerable high water flux. All of Escherichia coli and Staphylococcus aureus cells can be intercepted but bovine serum albumin penetrated easily without obvious adhesion behavior to membrane surface. In addition, after attached with the membrane, above bacteria were inactive effectively with rate of 99.99%. Compared to control samples, the composite membrane presents excellent repetitive-use filtration performance after back-washing test indicating its superior anti-biofouling properties. These results can be assigned to the optimized surface of porous composite membranes synergistically determined by the network nanofiber scaffold and high active polydopamine. It is believed that the as-prepared membrane provides a new approach in treating of water body full of microbes.