Chlorine Rechargeable Biocidal N-Halamine Nanofibrous Membranes Incorporated with Bifunctional Zwitterionic Polymers for Efficient Water Disinfection Applications

An intrinsically hydrophilic nanofibrous membrane with chlorine rechargeable biocidal and antifouling functions was prepared by using a combination of chemically bonded N-halamine moieties and zwitterionic polymers (PEI-S). The designed nanofibrous membrane, named as PEI-S@BNF-2 h, can exhibit integrated features of reduced bacterial adhesion, rechargeable biocidal activity, and easy release of killed bacteria by using mild hydrodynamic forces. The representative functional performances of the PEI-S@BNF-2 h membrane include high active chlorine capacity (>4000 ppm), large specific surface area, ease of chlorine rechargeability, long-term stability, and exceptional biocidal activity (99.9999% via contact killing). More importantly, the zwitterionic polymer moieties (PEI-S) brought robust antifouling properties to this biocidal membrane, therefore reducing the biofouling-biofilm effect and prolonging the lifetime of the filtration membrane. These attributes enable the PEI-S@BNF-2 h nanofibrous membrane to effectively disinfect the microbe-contaminated water with high fluxes (10,000 L m–2 h–1) and maintain itself clean for a long-term application.