High-Performance photoinduced antimicrobial membrane toward efficient PM2.5-0.3 capture and Oil-Water separation

Abstract

Design and fabrication of highly efficient and multifunctional nanofiber membranes for biological protection and environmental conservation has attracted wide attention. Herein, a unique bimodal fiber diameter distributed polyvinylidene fluoride (PVDF) composite membrane decorated by zeolitic imidazolate framework-8 (ZIF8) featuring favorable antibacterial activity was successfully prepared for efficient particulate matter (PM) capture and oil–water separation via a simple and feasible electrospinning process. Benefiting from the metal ions (Zn2+) and organic ligands released by ZIF8, particularly the generated reactive oxygen species (ROS) under photoexcitation, the composite membrane presented strong bactericidal activity against Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli). More impressively, owing to the effective drug loading capacity of ZIF8, the cefixime-encapsulated nanofiber membrane further exhibited remarkably enhanced antibacterial properties. Meanwhile, composite membrane achieved superior capture efficiency (99.90 ± 0.05 %) for PM0.3 and high purification ability (99.40 ± 0.10 %) for PM2.5 in real smoke environment under the combined effect of the strong surface charge on ZIF8 surface, high polarity of β-phase in PVDF, and ultrafine fibers, etc.; it also possessed excellent separation ability for water-in-oil emulsion and oil–water mixture due to the distinguished selective wettability, three dimensional porous structure and the enhanced demulsification performance of ZIF8. This multifunctional filtration/separation composite membrane emerges great potential in the fields of biological protection, air pollution control and oil–water separation.