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[Display omitted] • A facile strategy was developed to promote heat dissipation and noise reduction. • Heat-conducting elastic fiber sponges with boron nitride were first constructed. • Sponges exhibit good heat dissipation with thermal conductivity of 0.159 W m−1 K−1. • Elastic PU and crosslinking endow sponges with robust elastic and tensile properties. • Sponges can reduce noise by 28.3 dB with a high noise reduction coefficient of 0.64. Industrial and traffic noise has become increasingly serious with the progress of industrialization. Most existing noise-absorbing materials suffer from poor heat dissipation and insufficient low-frequency (<1000 Hz) noise absorption, which not only reduces working efficiency but also leads to safety risks. Herein, heat-conducting elastic ultrafine fiber sponges with boron nitride (BN) networks were prepared by integrating direct electrospinning and impregnation method. The large acoustic contact area of ultrafine fibers and the vibration effect of BN nanosheets in a three-dimensional direction endow fiber sponges with good noise reduction, which can reduce white noise by 28.3 dB with a high noise reduction coefficient of 0.64. Moreover, thanks to good heat-conducting networks composed of BN nanosheets and porous structures, the obtained sponges exhibit superior heat dissipation with thermal conductivity of 0.159 W m−1 K−1. Besides, the introduction of elastic polyurethane and following crosslinking endow the sponges with good mechanical properties, which have almost no plastic deformation after 1000 compressions, and the tensile strength and strain are as high as 0.28 MPa and 75%. The successful synthesis of heat-conducting elastic ultrafine fiber sponges overcomes poor heat dissipation and low-frequency noise reduction of noise absorbers. [ABSTRACT FROM AUTHOR]

[Display omitted] Noise has been regarded as an environmental pollutant that greatly affects people's physical and psychiatric health. Fibrous sound absorption materials are widely used to release the annoyance that brought by noise pollution, however, the fibrous materials are limited by poor sound absorption ability in low-frequency, heavyweight, and excessive thickness. Herein, composite nanofiber aerogels are designed with a hierarchical maze-like microstructure, which is fabricated by interweaving the cellulose nanocrystal lamellas with polyacrylonitrile electrospun nanofiber networks through the freeze-casting technique. The designed maze-like structure shows obvious enhancement in the low-frequency sound absorption band compared to the fiber aerogels made by the network structure. Moreover, through carefully regulating the maze structure, composite nanofiber aerogels with excellent sound absorption performance (with an NRC of 0.58) and lightweight property (11.05 mg cm−3) can be fabricated. In addition to the superior sound absorption ability, the hierarchical nature of the maze-like structure also guarantees the nanofiber aerogels with robust mechanical properties, which can be tailored to various shaped objects on a large scale. These favorable characters present that the composite nanofiber aerogels potential choice for sound absorption in the fields of vehicles, buildings, and indoor reverberation. [ABSTRACT FROM AUTHOR]

Nanofiber-structured hydrogels with robust mechanical properties are promising candidates for the development of multifunctional materials in advanced fields. However, creating such materials that combine the virtues of high elongation, robust strength, and good elasticity remains an enormous challenge. Here, we demonstrate a nature-inspired methodology to fabricate dermis-mimicking network structured electrospun nanofibrous hydrogels with robust mechanical properties by combining the advantages of sustainable plant-based zein and elastic waterborne polyurethane (WPU). The reversible hydrogen bonding and strong covalent bonding between zein and WPU molecules are constructed in the double-network (DN) structured nanofibrous hydrogels (NFHs) with tunable stretchability and strength. The resulting NFHs exhibit the integrated characteristics of a stretch of 683%, a fracture strength of 6.5 MPa, a toughness of 20.7 MJ m−3, and complete recovery from large deformation. This nature-inspired structural design strategy may pave the way for designing mechanically robust nanofibrous hydrogels in structurally adaptive and scalable form. [ABSTRACT FROM AUTHOR]

Frequent outbreaks of emerging infectious diseases (EIDs) make personal protective filter media in high demand. Electrospun nanofibrous materials are proved to be very effective in resisting virus-containing fine particles owing to their small fiber diameters; however, hindered by the intrinsic close-packing character of fine fibers, electrospun filters suffer from a relatively high air resistance, thereby poor breathing comfort. Here, we report a biomimetic and one-step strategy to create ultrafine and curly wool-like nanofibers, named nano-wool, which exhibit fluffy assembly architecture and powerful electret effect. By achieving the online self-crimp and in-situ charging of nanofibers, the curly electret nano-wool shows a small diameter of ~0.6 μm (two orders of magnitude lower than natural wool: ~20 μm) and an ultrahigh porosity of 98.7% simultaneously, together with an ultrahigh surface potential of 13260 V (one order of magnitude higher than previous filters). The structural advantages and powerful electret effect enable nano-wool to show excellent filtration efficacy (>99.995% for PM 0.3) and low air resistance (55 Pa). Additionally, nano-wool can be easily scaled up, not only holding great industrial prospect in personal protective respirators, but also paving the way for developing next-generation wool in a cost-efficient and multifunctional form. [ABSTRACT FROM AUTHOR]

Exploiting high-added-value textiles equipped with multiple functionalities like ultraviolet (UV) resistance, waterproofness, and thermal-moisture comfort is facing tremendous demand by a more discerning consumer market. However, the major challenge is to realize the equilibrium among the multifunction. Herein, a new attempt of fabricating superhydrophobic electrospun polyacrylonitrile (PAN)/polyurethane (PU)/titanium dioxide (TiO 2 ) nanofibrous membranes has been tried, and the membranes exhibited multifunction of UV resistance, waterproofness and breathability by coating modification with 2-hydroxy-4- n -octoxybenzophenone (UV531) and fluorinated acrylic copolymer (FAC). TiO 2 NPs as inorganic blocker and UV531 as organic absorber were utilized to impart the excellent double UV resistant function for the modified nanofibrous membranes. The hydrophobic coating with FAC endowed the pristine membranes with enhanced superhydrophobic wettability and the advancing contact angle was 152.1°. Regulating the addition amount of TiO 2 NPs, the UV531 and FAC concentration, the multiple functionalities of the modified PAN/PU/TiO 2 were systemically optimized: robust tensile strength (14.6 MPa), good ultraviolet protection factor of 1485, modest waterproofness (62 kPa), and moisture breathability (12.9 kg m −2 d −1 ). The equilibrium among the multifunction of the as-prepared membranes indicated their diverse possibilities can be used in various applications, including high-altitude garments, protective clothing, covering materials, self-cleaning materials, and other medical products. [ABSTRACT FROM AUTHOR]

Flexible CNNMs with freestanding Cu(OH) 2 nanosheets were designed by in-suit coprecipitation and heat-induced growth. The nanosheets were rooted tightly on the PVB nanofibers. The as-prepared membranes exhibited superior bactericidal efficiency and ultrahigh flux, which can be used to disinfect bacteria-containing water effectively. [Display omitted] Copper hydroxide (Cu(OH) 2) has been elected as a newly-emerging green disinfectant to deal with membrane biofouling in the treatment of bacteria-contaminated water; however, the decoration strategy of it with the granular form on membrane substrates limits the practical application. Here a novel surface-confined methodology was proposed for preparing freestanding Cu(OH) 2 nanosheet-assembled nanofibrous membranes (CNNMs) with the anti-biofouling property via the in-suit coprecipitation and heat-induced growth method. The vertically aligned Cu(OH) 2 nanosheets were in-suit rooted on the surface of the nanofiber scaffold with high binding fastness. The acquired CNNMs possess comprehensive performances of high porosity, prominent mechanical strength, fatigue resistance, and superior bactericidal efficiency of 99.999%, which endowed the CNNMs ultrahigh filtration fluxes (24000 L m−2 h−1) and durability to disinfect bacteria-containing water effectively. This facile strategy may throw light on manufacturing novel inorganic nanosheet-rooted nanofibrous membranes for water disinfection and public health. [ABSTRACT FROM AUTHOR]

[Display omitted] Ultrafine fibrous porous materials obtained by electrospinning technology have broad application prospects in the field of noise reduction. However, the two-dimensional fibrous membranes faced low thickness and dense structure, resulting in a single internal structure and narrow sound absorption band. Here, we report a simple and robust strategy to prepare gradient structured fiber sponges with superelasticity and stretchability by combining humidity-assisted multi-step electrospinning and a unique physical/chemical dual cross-linking method. The prepared gradient structured fibrous sponge has a maximum tensile strength of 169 kPa and can lift a weight 10,000 times its weight without breaking. Besides, the material can still maintain a stable structure after 500 compression cycles at 60% strain. Meantime, the material has lightweight properties (density of 13.8 mg cm−3) and hydrophobicity (water contact angle of 152°). More importantly, the gradient change of porosity and pore diameter in the Z direction endowed the fibrous sponge material with high-efficiency absorption of broadband sound waves (with a noise reduction coefficient up to 0.53). The design of this gradient structured fiber sponge opens a new way for the development of ideal sound-absorbing materials. [ABSTRACT FROM AUTHOR]

A portable electrospinning device was designed and fibrous membranes could be fabricated directly onto human skin by in-situ electrospinning. The resultant fibrous membranes exhibited excellent waterproof and breathable performances contributing to the comfort of skin in practical usage. [Display omitted] Skin-like flexible membrane with excellent water resistance and moisture permeability is an urgent need in the wound dressing field to provide comfort and protection for the wound site. Despite efforts that have been made in the development of waterproof and breathable (W&B) membranes, the in-situ electrospinning of W&B membranes suitable for irregular wound surfaces as wound dressings still faces huge challenges. In the current work, a portable electrospinning device with multi-functions, including adjustable perfusion speed for a large range from 0.05 mL/h to 10 mL/h and high voltage up to 11 kV, was designed. The thymol-loaded ethanol-soluble polyurethane (EPU) skin-like W&B nanofibrous membranes with antibacterial activity were fabricated via the custom-designed device. Ultimately, the resultant nanofibrous membranes composed of EPU, fluorinated polyurethane (FPU), and thymol presented uniform structure, robust waterproofness with the hydrostatic pressure of 17.6 cm H 2 O, excellent breathability of 3.56 kg m−2 d−1, the high tensile stress of 1.83 MPa and tensile strain of 453%, as well as high antibacterial activity. These results demonstrate that the new-type device has potential as a portable electrospinning apparatus for the fabrication of antibacterial membranes directly on the wound surface and puts a new way for the development of portable electrospinning devices. [ABSTRACT FROM AUTHOR]

Graphical abstract A novel strategy to prepare CuFe 2 O 4 nanostructures functionalized SiO 2 nanofibrous membranes with outstanding softness, favorable magnetic susceptibility, and high catalytic activity for the degradation of organic pollutant. Abstract Fenton or Fenton-like technique, as one of the advanced oxidation processes, plays a significant role in the removal of non-easily degradable organic pollutants; however, most of such catalysts are fragile with poor structural integrity under large deformation, thereby restricting their wide applications. Herein, soft copper ferrite nanostructures functionalized silica nanofibrous membranes (CuFe 2 O 4 @SNM) were fabricated through a novel strategy with the combination of in-situ dopamine polymerization, ion adsorption, and cohesive precipitation method. Benefiting from the high metallic ion adsorption capacity of polydopamine together with the rapid co-precipitation of adsorbed ions on fiber surface in alkaline solution, the membranes possessed homogenously distributed nanostructured CuFe 2 O 4 , large specific surface area, and high pore volume, which are a benefit for the improvement of Fenton-like catalytic activity towards organic pollutants decomposition. The resultant soft CuFe 2 O 4 @SNM provided favorable catalytic performance towards organic pollutants with a relatively high degradation degree of 96% in 20 min, a fast removal rate of 0.148 min−1, and outstanding recyclability. The successful preparation of such fascinating ceramic nanofibrous membranes would provide a reference for further exploitation of new type Fenton or Fenton-like catalysts with outstanding softness towards wastewater purification. [ABSTRACT FROM AUTHOR]

Construction ion-exchange membranes with superb biomolecules adsorption and purification performance plays a greatly important role in the fields of biotechnological and biopharmaceutical industry, yet still remains an extremely challenging. Herein, we in situ synthesized the cis-butenedioic anhydride grafted poly(vinyl alcohol) hydrogel nanofibrous membranes (CBA- g -PVA HNFM) by combining electrospinning technique with the grafting-copolymerization crosslinking. Taking advantages of the large specific surface area which could provide numerous sites available for functional groups and biomolecules binding, highly tortuous and interconnected porous channel for biomolecules transfer, and enhanced mechanical strength, the resultant CBA- g -PVA HNFM exhibited relatively high binding amount of 170 mg g −1 , rapid equilibrium time of 8 h towards the biomolecule template of lysozyme, and the performance could be tailored by regulating the buffer properties and protein concentrations. Additionally, the resultant functional HNFM also possessed superior acid resistance property, excellent reversibility and regeneration performance. More importantly, the obtained CBA- g -PVA HNFM could directly extract lysozyme from fresh chicken eggs with capacity of 125 mg g −1 , exhibiting excellent practical application properties. The fabrication of proposed CBA- g -PVA HNFM offers a feasible alternative for construction of ion-exchange chromatograph column for bio-separation and purification engineering. [ABSTRACT FROM AUTHOR]