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 (Zn 2+ ) 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 PM 0.3 and high purification ability (99.40 ± 0.10 %) for PM 2.5 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.
The performance of moisture management, PM capture, and bacteria inhibition are significant for air cleaning materials. Herein, a nanofiber composite PVDF/PAN-CTAB membrane with multiple functions was constructed via a facile electrospinning strategy. Incorporating cetyltrimethyl ammonium bromide (CTAB) in the windward PAN layer simultaneously improved membrane moisture transport rate, antibacterial performance, and PM capture ability. The enhanced moisture management performance was achieved by regulating the microstructure of the nanofibers and the thickness ratio of the asymmetric wetting layers. Hydrophobic-hydrophilic interface superimposed force on water droplets was measured to thoroughly investigate directional water transport behavior. Consequently, the prepared PVDF/PAN-CTAB membrane possesses a water vapor transport rate of >13 kg m −2 d −1 , PM 0.3 removal efficiency of ≥99% with a low pressure drop of ∼84 Pa, and an E. coli inhibition rate of 99.99%. This work would pave the way for engineering asymmetric wettability structure to improve the moisture management performance of antibacterial air cleaning membrane, and provides a novel scientific sight on directional water transport phenomenon based on force test and analysis.
Developing cost-effective and high-efficient air purification materials for enhancing the indoor air quality has been an ongoing concern. Herein, MnO 2 /Co–C catalyst layers were wrapped on SiO 2 nanofiber by a combination of thermal pyrolysis and redox reaction method to prepare catalytic membranes (MCCS-x) for the efficient purification of indoor PM and HCHO. The core-dual-shell structure maintains the pore structure of the membrane, providing high gas permeability of 670 m 3 ·m −2 ·h −1 ·kPa −1 . Owing to the introduction of MnO 2 /Co–C enhanced the capture of PM, the optimized MCCS-2 exhibits high filtration efficiency of PM 0.3 and PM 2.5 (99.60% and 99.99%) with a low pressure drop (<80 Pa). In addition, MCCS-2 achieves 100% HCHO removal efficiency at room temperature due to its large specific surface area, high redox property and abundant Mn 4+ and oxygen species. The appropriate proportion of Mn/Co bimetallic sites synergy inhibits the formation of formate and carbonate intermediate species, thus MCCS-2 possesses excellent long-term catalytic stability than contrast sample (MCCS-3 and MS). This work demonstrates a new approach for the fabrication of high-performance catalytic membrane materials for indoor air purification.
危险品化学品经营许可证（带存储）