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With the widespread concern of oily wastewater discharge and environmental protection, the efficient electrospun nanofiber membrane has fascinated strenuous attention owes to its uniform pore distribution and adjustable wettability. However, the common modification methods of nanofiber membranes, such as surface coating and grafting, have complicated procedures and low grafting rate, which limits their wide application in practical applications. Hence, a polyvinylidene fluoride (PVDF), polyvinylpyrrolidone (PVP) and inorganic titanium dioxide (TiO 2) nanoparticles blend nanofiber membrane was prepared by convenient one-step electrostatic spinning. The existence of PVDF provides certain strength and chemical resistance property, and the PVP benefits the loading of TiO 2 NPs and improves the hydrophilicity as well as mechanical strength of the membrane. The introduction of these three components makes the porous nanofiber membrane have a hierarchical rough structure, and appear hydrophilic in the air and oleophobic under water. The obtained membrane thus shows excellent separation efficiency (98.4%) for different emulsions, desirable antifouling property with a high flux recovery rate (FRR 95.68%) and a low total fouling ratio (15.18%) after several cycles. This strategy will be a facile and promising method of preparing reusable and functional separation membranes. [Display omitted] • The PVDF membrane was prepared by one-step electrostatic spinning. • The membrane was modified by adding water-soluble polymer PVP and TiO 2. • The membrane showed durable anti-fouling and oil-water separation properties. [ABSTRACT FROM AUTHOR]

In this paper, titanium dioxide (TiO2)/quaternary phosphonium salts (QPS)/polyacrylonitrile (PAN) composite nanofibrous membranes were prepared through electrospinning to fabricate organic and inorganic complex highly efficient antibacterial and ultraviolet (UV)-resistant membranes. The composite material derived from QPS was designed effectively kill bacteria and improve quaternary ammonium salts' drug-resistant problem, while the addition of TiO2 can absorb ultraviolet light to catalyze sterilization and decompose residues. The obtained membranes were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transfer infrared spectroscopy (FTIR), thermogravimetric analysis (TG), ultraviolet protection factor (UPF), and antibacterial tests. SEM images indicate slim and uniform morphology of fibers with a diameter of 0.1–0.2 um. FTIR and XPS tests confirm the existence of QPS and TiO2 compounds in the composite membranes, and there is no chemical bond between these substrates and PAN. TG test implies that the membranes have a good thermal stability. UPF of 1648.1 and UVA transmittance of 0.28% indicate that the TiO2/QPS/PAN membranes have an extraordinary UV resistance property. The antibacterial tests show that complex membranes have 99.99% antibacterial rate against both gram-negative Escherichia coli and gram-positive Staphylococcus aureus. [ABSTRACT FROM AUTHOR]