Thin PVA/nickel acetate composite fibres were prepared by using sol-gel processing and electrospinning technique. After calcination of the above precursor fibres, NiO nanofibres with a diameter of 50-150 nm could be ...Thin PVA/nickel acetate composite fibres were prepared by using sol-gel processing and electrospinning technique. After calcination of the above precursor fibres, NiO nanofibres with a diameter of 50-150 nm could be successfully obtained. The fibres were characterized by SEM, FT-IR, WAXD, respectively.展开更多
Poly（vinylpyrrolidone）/tetrabutyl titanate （PVP/ [CH3（CH2）3O]4Ti） composite nanofibres are prepared by electrospinning. After calcining parts of composite nanofibres in air at 700 ~℃, petal-like TiO2 nanostruct...Poly（vinylpyrrolidone）/tetrabutyl titanate （PVP/ [CH3（CH2）3O]4Ti） composite nanofibres are prepared by electrospinning. After calcining parts of composite nanofibres in air at 700 ~℃, petal-like TiO2 nanostructures are obtained. The characterizations of composite nanofibres and TiO2 nanostructures are carried out by a scanning electron microscope, an x-ray diffractometer, and an infrared spectrometer. Electrospun nanofibres are pressed into pellets under different pressures in order to explore their dielectric properties. It is found that the dielectric constants decrease with frequency increasing. The dielectric constant of the composite nanofibre pellet increases whereas its dielectric loss tangent decreases due to the doped titanium ions compared with those of pure PVP nanofibre pellets. In addition, it is observed that the dielectric constant of the composite nanofibre pellet decreases with the increase of the pressure applied in pelletization.展开更多
H+ doped polyaniline nanofibre(PH) was synthesized by interfacial polymerization and polyanilines doped with Li salt(PLI and PHLI) were prepared by immersing emeraldine base(EB) and H+ doped polyaniline in 1 mol/L LiP...H+ doped polyaniline nanofibre(PH) was synthesized by interfacial polymerization and polyanilines doped with Li salt(PLI and PHLI) were prepared by immersing emeraldine base(EB) and H+ doped polyaniline in 1 mol/L LiPF6/(EC-EMC-DMC),respectively.PH,PLI and PHLI were all characterized by scanning electron microscopy(SEM) and Fourier transform infrared(FT-IR) spectrometry.With 1 mol/L LiPF6/(EC-EMC-DMC) as electrolyte,PH,PHLI and PLI were used as the active materials of symmetric non-aqueous redox supercapacitors.PLI shows the highest initial specific capacitance of 120 F/g(47 F/g for PH and 66 F/g for PHLI) among three samples.After 500 cycles,the specific capacitance of PLI remains 75 F/g,indicating the good cycleability.展开更多
NiZn ferrite/polyvinylpyrrolidone composite fibres were prepared by sol,el assisted electrospinning. Ni0.5Zn0.5Fe2O4 nanofibres with a pure cubic spinel structure were obtained subsequently by calcination of the compo...NiZn ferrite/polyvinylpyrrolidone composite fibres were prepared by sol,el assisted electrospinning. Ni0.5Zn0.5Fe2O4 nanofibres with a pure cubic spinel structure were obtained subsequently by calcination of the composite fibres at high temperatures. This paper investigates the thermal decomposition process, structures and morphologies of the electrospun composite fibres and the calcined Ni0.5Zn0.5Fe2O4 nanofibres at different temperatures by thermo-gravimetric and differential thermal analysis, x-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscopy. The magnetic behaviour of the resultant nanofibres was studied by a vibrating sample magnetometer. It is found that the grain sizes of the nanofibres increase significantly and the nanofibre morphology graduMly transforms from a porous structure to a necklace-like nanostructure with the increase of calcination tempera-ture. The Ni0.5Zn0.5Fe2O4 nanofibres obtained at 1000℃ for 2h are characterized by a necklace-like morphology and diameters of 100-200nm. The saturation magnetization of the random Ni0.5Zn0.5Fe2O4 nanofibres increases from 46.5 to 90.2 emu/g when the calcination temperature increases from 450 to 1000℃. The coercivity reaches a maximum value of 11.0 kA/m at a calcination temperature of 600℃. Due to the shape anisotropy, the aligned Ni0.5Zn0.5Fe2O4 nanofibres exhibit an obvious magnetic anisotropy and the ease magnetizing direction is parallel to the nanofibre axis.展开更多
Ca and Mn co-doped BiFeO3 ultrafine nanofibres were prepared with the purpose of improving magnetic and photocatalytic performances of the one-dimensional multiferroic material. Impurity phase introduced by both Bi fl...Ca and Mn co-doped BiFeO3 ultrafine nanofibres were prepared with the purpose of improving magnetic and photocatalytic performances of the one-dimensional multiferroic material. Impurity phase introduced by both Bi fluctuation and Mn substitution can be suppressed by Ca doping and a space group transition from R3c to C222 can also be triggered by Bi-site doping. With co-substitution of Mn into iron site, the Ca0.15Bi0.85Mn0.05Fe0.95O3 nanofibres presented a larger saturation magnetization than the singly Ca doping samples, possibly due to the increased double exchange interation of Fe3+-O-Fe2+, strengthened by Ca and Mn. Photocatalytic degradation test witnessed a similar drop-and-rise performance with the magnetism.展开更多
Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always...Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always struggle to balance mechanical properties and thermal insulation,resulting in their inability to meet the demands for both washing resistance and personal protection.Herein,inspired by the natural spring-like structures of cucumber tendrils,a superelastic and washable micro/nanofibrous sponge(MNFS)based on biomimetic helical fibers is directly prepared utilizing multiple-jet electrospinning technology for high-performance thermal insulation.By regulating the conductivity of polyvinylidene fluoride solution,multiple-jet ejection and multiple-stage whipping of jets are achieved,and further control of phase separation rates enables the rapid solidification of jets to form spring-like helical fibers,which are directly entangled to assemble MNFS.The resulting MNFS exhibits superelasticity that can withstand large tensile strain(200%),1000 cyclic tensile or compression deformations,and retain good resilience even in liquid nitrogen(-196℃).Furthermore,the MNFS shows efficient thermal insulation with low thermal conductivity(24.85 mW m^(-1)K^(-1)),close to the value of dry air,and remains structural stability even after cyclic washing.This work offers new possibilities for advanced fibrous sponges in transportation,environmental,and energy applications.展开更多
The research,fabrication and development of piezoelectric nanofibrous materials offer effective solutions to the challenges related to energy consumption and non-renewable resources.However,enhancing their electrical ...The research,fabrication and development of piezoelectric nanofibrous materials offer effective solutions to the challenges related to energy consumption and non-renewable resources.However,enhancing their electrical output still remains a significant challenge.Here,a strategy of inducing constrained phase separation on single nanofibers via shear force was proposed.Employing electrospinning technology,a polyacrylonitrile/polyvinylidene difluoride(PAN/PVDF)nanofibrous membrane was fabricated in one step,which enabled simultaneous piezoelectric and triboelectric conversion within a single-layer membrane.Each nanofiber contained independent components of PAN and PVDF and exhibited a rough surface.The abundant frictional contact points formed between these heterogeneous components contributed to an enhanced endogenous triboelectric output,showcasing an excellent synergistic effect of piezoelectric and triboelectric response in the nanofibrous membrane.Additionally,the component mass ratio influenced the microstructure,piezoelectric conformation and piezoelectric performance of the PAN/PVDF nanofibrous membranes.Through comprehensive performance comparison,the optimal mass ratio of PAN to PVDF was determined to be 9∶1.The piezoelectric devices made of the optimal PAN/PVDF nanofibrous membranes with rough nanofiber surfaces generated an output voltage of 20 V,which was about 1.8 times that of the smooth one at the same component mass ratio.The strategy of constrained phase separation on the surface of individual nanofibers provides a new approach to enhance the output performance of single-layer piezoelectric nanofibrous materials.展开更多
The random nanofiber distribution in traditional electrospun membranes restricts the pressure sensing sensitivity and measurement range of electronic skin.Moreover,current multimodal sensing suffers from issues like o...The random nanofiber distribution in traditional electrospun membranes restricts the pressure sensing sensitivity and measurement range of electronic skin.Moreover,current multimodal sensing suffers from issues like overlapping signal outputs and slow response.Herein,a novel electrospinning method is proposed to prepare double-coupled microstructured nanofibrous membranes.Through the effect of high voltage electrostatic field in the electrospinning,the positively charged nanofibers are preferentially attached to the negatively charged foam surface,forming the ordered two-dimensional honey-comb porous nanofibrous membrane with three-dimensional spinous microstructure.Compared with the conventional random porous nanofibrous membrane,the bionic two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructures in the ordered porous nanofibrous membrane endows the electronic skin with significantly improved mechanical properties(maximum tensile strain increased by 77%and fatigue resistance increased by 35%),air permeability(water vapor transmission rate increased by 16%)and sensing properties(pressure sensitivity increased by 276%and detection range increased by 137%).Furthermore,the electronic skin was constructed by means of a conformal composite ionic liquid functionalized nanofibrous membrane,and the real-time and interference-free dualsignal monitoring of pressure and temperature(maxi-mum temperature coefficient of resistance:−0.918°C^(−1))was realized.展开更多
Flexible electronic skin(E-skin)sensors offer innovative solutions for detecting human body signals,enabling human-machine interactions and advancing the development of intelligent robotics.Electrospun nanofibers are ...Flexible electronic skin(E-skin)sensors offer innovative solutions for detecting human body signals,enabling human-machine interactions and advancing the development of intelligent robotics.Electrospun nanofibers are particularly wellsuited for E-skin applications due to their exceptional mechanical properties,tunable breathability,and lightweight nature.Nanofiber-based composite materials consist of three-dimensional structures that integrate one-dimensional polymer nanofibers with other functional materials,enabling efficient signal conversion and positioning them as an ideal platform for next-generation intelligent electronics.Here,this review begins with an overview of electrospinning technology,including far-field electrospinning,near-field electrospinning,and melt electrospinning.It also discusses the diverse morphologies of electrospun nanofibers,such as core-shell,porous,hollow,bead,Janus,and ribbon structure,as well as strategies for incorporating functional materials to enhance nanofiber performance.Following this,the article provides a detailed introduction to electrospun nanofiber-based composite materials(i.e.,nanofiber/hydrogel,nanofiber/aerogel,nanofiber/metal),emphasizing their recent advancements in monitoring physical,physiological,body fluid,and multi-signal in human signal detection.Meanwhile,the review explores the development of multimodal sensors capable of responding to diverse stimuli,focusing on innovative strategies for decoupling multiple signals and their state-of-the-art advancements.Finally,current challenges are analyzed,while future prospects for electrospun nanofiber-based composite sensors are outlined.This review aims to advance the design and application of next-generation flexible electronics,fostering breakthroughs in multifunctional sensing and health monitoring technologies.展开更多
Nanofiber scaffold has built a bionic microenvironment for bone marrow mesenchymal stem cells by highly simulating the topological structure of natural extracellular matrix.Its ordered fiber network effectively guides...Nanofiber scaffold has built a bionic microenvironment for bone marrow mesenchymal stem cells by highly simulating the topological structure of natural extracellular matrix.Its ordered fiber network effectively guides the directional migration and spatial arrangement of cells through the mechanical signal transduction mediated by integrin.Surface functionalization can synergistically activate the osteogenic transcription network and significantly enhance the osteogenic differentiation potential of cells.The precise design of scaffold stiffness affects the cell fate choice by regulating the nuclear translocation of mechanical sensitive factors.This triple cooperative strategy of“physical topology-biochemical signal-mechanical microenvironment”effectively overcomes the biological inertia of traditional scaffolds and provides a dynamic and adjustable platform for bone defect repair.Looking forward to the future,breaking through the bottleneck of clinical transformation such as long-term intelligent slow release of functional factors and in situ efficient construction of vascular network is the key to promoting nanofiber scaffolds from basic research to precise bone regeneration treatment.展开更多
A self-standing dual-electric field synergistic[TiO_(2)/polyvinylidene fluoride(PVDF)]//[g-C3 N4 tube/PVDF]Janus nanofibres(named as[TP]//[CTP]JNs)S-scheme heterostructure piezoelectric photocatalyst is designed and c...A self-standing dual-electric field synergistic[TiO_(2)/polyvinylidene fluoride(PVDF)]//[g-C3 N4 tube/PVDF]Janus nanofibres(named as[TP]//[CTP]JNs)S-scheme heterostructure piezoelectric photocatalyst is designed and constructed via conjugative electrospinning.Dual-fields of built-in electric fields supplied by S-scheme heterostructure and piezoelectric field formed by PVDF jointly boost separation and transfer of photo-induced charges.As a case study,piezoelectric photocatalytic efficiency of[TP]//[CTP]JNs for tetracycline hydrochloride(TCH)under ultrasonic united with simulated sunlight illumination is 93.35%(40 min),which is 1.39 times of the photocatalytic efficiency(light illumination only)and 5.32 times of piezoelectric catalytic efficiency(applying ultrasonic only),proving the advantages of the synergistic effect of piezoelectric catalysis and photocatalysis on contaminant degradation.The dynamic behaviors of photocatalysis and photo-generated charges are deeply revealed through fs-TA and TRPL decay spectra,and the degradation pathways of antibiotics are reasonably speculated by combining LCMS spectra with Fukui index.By the degradation ability,COMSOL simulation and DFT calculation,the structural advantage of Janus nanofibers is fully verified,and S-scheme charge transfer mechanism is confirmed by combining a series of sound ample experiments with theoretical calculations.Additionally,the construction mechanism of Janus nanofibers is proposed,and corresponding construction technique is established.展开更多
Due to some intrinsic functional behavior of alginate, many potential applications in the healthcare industry especially in wound care sector are observed. Many researches have been carried out to develop potential bi...Due to some intrinsic functional behavior of alginate, many potential applications in the healthcare industry especially in wound care sector are observed. Many researches have been carried out to develop potential biomedical biocompatible products in different forms from alginate fibres. Alginate nanofibres were prepared from sodium alginate polymer with the presence of poly-(ethylene oxide) (PEO), a small amount of Triton ×100 surfactant. A homogeneous spinning solution was prepared for producing Na-alginate/PEO nanofibers in electrospinning device. Nanofibres were produced by electrospinning from 70:30 and 80:20 Na-alginate/PEO of 4% solution. After a series of trials, the electrospinning parameters were optimized at 16 cm working distance, 0.4 mL/h flow rate and 10.5 kV applied voltage. The results show that the 4 wt% of 70:30 Na-alginate/PEO solution with 0.5 wt% Triton × 100 surfactant yielded smooth and stable electrospinning. The surface morphology of the fibres was investigated using Scanning Electron Microscope (SEM) and found the uniform fibres with an average diameter of 124 nm containing few thick or spindle-like fibres. FTIR investigation identified the chemical structure and molecular changes that occurred in the fibers.展开更多
High-repetition-rate femtosecond lasers enable the precise production of nanofoam from a wide range of materials. Here, the laser-based fabrication of nanofoam from silicon, borosilicate glass, sodalime glass, gallium...High-repetition-rate femtosecond lasers enable the precise production of nanofoam from a wide range of materials. Here, the laser-based fabrication of nanofoam from silicon, borosilicate glass, sodalime glass, gallium lanthanum sulphide and lithium niobate is demonstrated, where the pore size of the nanofoam is shown to depend strongly on the material used, such that the pore width and nanofibre width appear to increase with density and thermal expansion coefficient of the material. In addition, the patterning of nanofoam on a glass slide, with fabricated pattern pixel resolution of ~35 μm, is demonstrated.展开更多
The rheological properties in question are influenced by many factors, ranging from the characteristics of the given polymer or solvent to the flowing conditions. The primary focus of this study is to analyse the rheo...The rheological properties in question are influenced by many factors, ranging from the characteristics of the given polymer or solvent to the flowing conditions. The primary focus of this study is to analyse the rheological behaviour of poly（vinyl butyral）—Mowital B 60 H—（PVB） solutions dissolved in methanol and a blend of these with fumed silica nanoparticles. The preparation of the nanofibrous web and the quality of nanofibres were correlated with the rheology of the polymer solution. It was discerned that drastically intensifying shear viscosity and the elasticity of the solution exerted a negligible effect on the formation of fibres, a finding which has rarely been discussed in the literature. The morphologies and structures of the PVB/silica nanofibrous membranes were investigated by scanning electron microscopy, thermogravimetric analysis and Fourier transform infrared spectroscopy.展开更多
Carbon nanofibers have revolutionized nanotechnology due to their potential applications in emerging frontiers of research and industrial sectors. This can be attributed to their superior properties such as higher mec...Carbon nanofibers have revolutionized nanotechnology due to their potential applications in emerging frontiers of research and industrial sectors. This can be attributed to their superior properties such as higher mechanical strength, unique surface characteristics, and improved adherence that is transmitted into the polymer matrix to form a nanocomposite with improved properties. Polymethyl methacrylate is a common carbon source for the synthesis of carbon nanofibres of its high mechanical strength, thermal stability, and low moisture and water absorbing capacity that allows its products to have several applications. In this work, we report the successful electrospinning of carbon nanofibres from Poly methyl methacrylate and functionalizing the resulting carbon nanofibres. The functionalized carbon nanofibres were analyzed to determine their solubility/dispersion in selected organic solvents, then characterized using Fourier transform infra-red spectroscopy, Raman spectroscopy, scanning electron microscopy combined with Energy dispersive spectroscopy and Thermalgravimetric analysis.展开更多
Diabetes is one of the most prevalent diseases in the world with high-mortality and complex complications including diabetic foot ulcer(DFU). It has been reported that the difficulties in repairing the wound related t...Diabetes is one of the most prevalent diseases in the world with high-mortality and complex complications including diabetic foot ulcer(DFU). It has been reported that the difficulties in repairing the wound related to DFU has much relationship with the wound infection,change of inflammatory responses, lack of extracellular matrix(ECM), and the failure of angiogenesis. Following the development of medical materials and pharmaceutical technology, nanofibers has been developed by electrospinning with huge porosity, excellent humidity absorption, a better oxygen exchange rate, and some antibacterial activities. That is to say, as a potential material, nanofibers must be a wonderful candidate for the DFU treatment with so many benefits. Careful selection of polymers from natural resource and synthetic resource can widen the nanofibrous application. Popular methods applied for the nanofibrous fabrication consist of uniaxial electrospinning and coaxial electrospinning. Furthermore, nanofibers loading chemical, biochemical active pharmaceutical ingredient(API)or even stem cells can be wonderful dosage forms for the treatment of DFU. This review summarizes the present techniques applied in the fabrication of nanofibrous dressing(ND)that utilizes a variety of materials and active agents to offer a better health care for the patients suffering from DFU.展开更多
The adsorption technology has been widely applied in water remediation for contamination removal of dyes and bacteria,by virtue of the advantages of adsorption technology including high efficiency,energy conservation ...The adsorption technology has been widely applied in water remediation for contamination removal of dyes and bacteria,by virtue of the advantages of adsorption technology including high efficiency,energy conservation and ease of operation.Simultaneous removal of dyes and bacteria has been realized by some reported materials,but to achieve satisfactory adsorption amounts and rates remain an unmet goal for decades.Herein,a poly(methacrylatoethyl trimethyl ammonium chloride-co-methyl methacrylate)copolymer was synthesized,and then blended with polyethersulfone for the fabrication of nanofibrous membranes via electrospinning for the use of fast and massive removal of dyes and bacteria.Owing to the introduction of abundant quaternary ammonium groups,the maximum adsorption amount for methyl orange was up to 909.8 mg g^(-1).In addition,the modified nanofibrous membranes showed good recyclability,broad applications in severe environments,selective adsorption ability,and excellent dynamic removal performance.Especially,thanks to the abundant functional groups,the membranes showed fast adsorption ability for bacteria through electrostatic interaction.It should be noted that the clearance ratio for Staphylococcus aureus or Escherichia coli by 6 min of static adsorption could reach 93%or 90%for each.Additionally,dynamic removal ratio via filtration with the nanofibrous membranes could reach 99.7%for Staphylococcus aureus or 98.7%for Escherichia coli in 90 s.Therefore,the proposed approach towards the quaternary ammonium modified polyethersulfone nanofibrous membranes creates a new route for ultra-high adsorption capacity and ultra-fast removal rates for dyes and bacteria in water remediation.展开更多
The acoustical damping property of electrospun polyacrylonitrile （PAN） nanofibrous membranes with different thicknesses and porosities was investigated. The sound absorption coefficients were measured using the impe...The acoustical damping property of electrospun polyacrylonitrile （PAN） nanofibrous membranes with different thicknesses and porosities was investigated. The sound absorption coefficients were measured using the impedance tube instrument based on ISO10534-2：1998（E）. Results indicate that the first resonance absorption frequency of nanofibrous membranes shifts to the lower frequency with the increase of the back cavity or the thickness of membranes. Moreover, the sound absorption performance of the perforated pane/ can be greatly improved by combination with a thin layer of PAN nanofibrous membrane. Traditional acoustical damping materials （foam, fiber） coated with nanofibrous membranes have better acoustical performance in the low and medium frequency range than that of acoustical materials alone. All of the results demonstrate the PAN nanofibrous membrane is a suitable candidate for noise reduction.展开更多
Adsorption and photocatalysis are regarded as two desirable technologies for wastewater remediation,but are still unsatisfactory in removal effect,eco-friendly regeneration and facile reusability.In this study,we deve...Adsorption and photocatalysis are regarded as two desirable technologies for wastewater remediation,but are still unsatisfactory in removal effect,eco-friendly regeneration and facile reusability.In this study,we developed a composite nanofibrous membrane material with excellent removal performance for organic pollutants based on synergistic adsorption and photocatalysis.A novel boron-doped,nitrogen-deficient graphitic carbon nitride(B-C3N4)photocatalyst as well as an amphiphilic copolymer of methyl methacrylate and acrylic acid(p(MMA-AA))were synthesized respectively,and then used to modify polyethersulfone for the fabrication of composite nanofibrous membrane with improved hydrophilicity,negativelycharge property and enhanced visible light response simultaneously.Subsequently,the synergistic effect of adsorption and photocatalytic degradation for organic pollutants were identified especially and resulted in an excellent removal efficiency even superior to the combination of adsorption and photocatalytic degradation,which could be called a“1+1>2”effect.In addition,the regeneration and reusability,the purification ability for multicomponent wastewater,and the photocatalytic mechanism,were investigated and discussed systematically.In this work,we not only prepared the nanofibrous membrane with synergistic effect of adsorption and photocatalysis,but also provided a versatile approach to design dualfunctional support material to ensure the practical applications of powdery photocatalyst in wastewater treatment.展开更多
One-dimensional(1D)SiO_(2) nanofibers(SNFs),one of the most popular inorganic nanomaterials,have aroused widespread attention because of their excellent chemical stability,as well as unique optical and thermal charact...One-dimensional(1D)SiO_(2) nanofibers(SNFs),one of the most popular inorganic nanomaterials,have aroused widespread attention because of their excellent chemical stability,as well as unique optical and thermal characteristics.Electrospinning is a straightforward and versatile method to prepare 1D SNFs with programmable structures,manageable dimensions,and modifiable properties,which hold great potential in many cutting-edge applications including aerospace,nanodevice,and energy.In this review,substantial advances in the structural design,controllable synthesis,and multifunctional applications of electrospun SNFs are highlighted.We begin with a brief introduction to the fundamental principles,available raw materials,and typical apparatus of electrospun SNFs.We then discuss the strategies for preparing SNFs with diverse structures in detail,especially stressing the newly emerging three-dimensional SiO_(2) nanofibrous aerogels.We continue with focus on major breakthroughs about brittleness-to-flexibility transition of SNFs and the means to achieve their mechanical reinforcement.In addition,we showcase recent applications enabled by electrospun SNFs,with particular emphasis on physical protection,health care and water treatment.In the end,we summarize this review and provide some perspectives on the future development direction of electrospun SNFs.展开更多
文摘Thin PVA/nickel acetate composite fibres were prepared by using sol-gel processing and electrospinning technique. After calcination of the above precursor fibres, NiO nanofibres with a diameter of 50-150 nm could be successfully obtained. The fibres were characterized by SEM, FT-IR, WAXD, respectively.
基金supported by the Program for New Century Excellent Talents in University of China (Grant No. NCET-07-0472)the National Natural Science Foundation of China (Grant No. 10604038)
文摘Poly（vinylpyrrolidone）/tetrabutyl titanate （PVP/ [CH3（CH2）3O]4Ti） composite nanofibres are prepared by electrospinning. After calcining parts of composite nanofibres in air at 700 ~℃, petal-like TiO2 nanostructures are obtained. The characterizations of composite nanofibres and TiO2 nanostructures are carried out by a scanning electron microscope, an x-ray diffractometer, and an infrared spectrometer. Electrospun nanofibres are pressed into pellets under different pressures in order to explore their dielectric properties. It is found that the dielectric constants decrease with frequency increasing. The dielectric constant of the composite nanofibre pellet increases whereas its dielectric loss tangent decreases due to the doped titanium ions compared with those of pure PVP nanofibre pellets. In addition, it is observed that the dielectric constant of the composite nanofibre pellet decreases with the increase of the pressure applied in pelletization.
基金Project(2008AA03Z207) supported by the National Hi-tech Research and Development Program of China
文摘H+ doped polyaniline nanofibre(PH) was synthesized by interfacial polymerization and polyanilines doped with Li salt(PLI and PHLI) were prepared by immersing emeraldine base(EB) and H+ doped polyaniline in 1 mol/L LiPF6/(EC-EMC-DMC),respectively.PH,PLI and PHLI were all characterized by scanning electron microscopy(SEM) and Fourier transform infrared(FT-IR) spectrometry.With 1 mol/L LiPF6/(EC-EMC-DMC) as electrolyte,PH,PHLI and PLI were used as the active materials of symmetric non-aqueous redox supercapacitors.PLI shows the highest initial specific capacitance of 120 F/g(47 F/g for PH and 66 F/g for PHLI) among three samples.After 500 cycles,the specific capacitance of PLI remains 75 F/g,indicating the good cycleability.
基金Project supported by the National Natural Science Foundation of China (Grant No 50674048)the Aerospace Science Foundation of China (Grant No 2007ZF52062)
文摘NiZn ferrite/polyvinylpyrrolidone composite fibres were prepared by sol,el assisted electrospinning. Ni0.5Zn0.5Fe2O4 nanofibres with a pure cubic spinel structure were obtained subsequently by calcination of the composite fibres at high temperatures. This paper investigates the thermal decomposition process, structures and morphologies of the electrospun composite fibres and the calcined Ni0.5Zn0.5Fe2O4 nanofibres at different temperatures by thermo-gravimetric and differential thermal analysis, x-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscopy. The magnetic behaviour of the resultant nanofibres was studied by a vibrating sample magnetometer. It is found that the grain sizes of the nanofibres increase significantly and the nanofibre morphology graduMly transforms from a porous structure to a necklace-like nanostructure with the increase of calcination tempera-ture. The Ni0.5Zn0.5Fe2O4 nanofibres obtained at 1000℃ for 2h are characterized by a necklace-like morphology and diameters of 100-200nm. The saturation magnetization of the random Ni0.5Zn0.5Fe2O4 nanofibres increases from 46.5 to 90.2 emu/g when the calcination temperature increases from 450 to 1000℃. The coercivity reaches a maximum value of 11.0 kA/m at a calcination temperature of 600℃. Due to the shape anisotropy, the aligned Ni0.5Zn0.5Fe2O4 nanofibres exhibit an obvious magnetic anisotropy and the ease magnetizing direction is parallel to the nanofibre axis.
文摘Ca and Mn co-doped BiFeO3 ultrafine nanofibres were prepared with the purpose of improving magnetic and photocatalytic performances of the one-dimensional multiferroic material. Impurity phase introduced by both Bi fluctuation and Mn substitution can be suppressed by Ca doping and a space group transition from R3c to C222 can also be triggered by Bi-site doping. With co-substitution of Mn into iron site, the Ca0.15Bi0.85Mn0.05Fe0.95O3 nanofibres presented a larger saturation magnetization than the singly Ca doping samples, possibly due to the increased double exchange interation of Fe3+-O-Fe2+, strengthened by Ca and Mn. Photocatalytic degradation test witnessed a similar drop-and-rise performance with the magnetism.
基金supported by Young Elite Scientists Sponsorship Program by China Association for Science and Technology(No.2022QNRC001)the National Natural Science Foundation of China(No.52273053)the Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.21CGA41)。
文摘Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always struggle to balance mechanical properties and thermal insulation,resulting in their inability to meet the demands for both washing resistance and personal protection.Herein,inspired by the natural spring-like structures of cucumber tendrils,a superelastic and washable micro/nanofibrous sponge(MNFS)based on biomimetic helical fibers is directly prepared utilizing multiple-jet electrospinning technology for high-performance thermal insulation.By regulating the conductivity of polyvinylidene fluoride solution,multiple-jet ejection and multiple-stage whipping of jets are achieved,and further control of phase separation rates enables the rapid solidification of jets to form spring-like helical fibers,which are directly entangled to assemble MNFS.The resulting MNFS exhibits superelasticity that can withstand large tensile strain(200%),1000 cyclic tensile or compression deformations,and retain good resilience even in liquid nitrogen(-196℃).Furthermore,the MNFS shows efficient thermal insulation with low thermal conductivity(24.85 mW m^(-1)K^(-1)),close to the value of dry air,and remains structural stability even after cyclic washing.This work offers new possibilities for advanced fibrous sponges in transportation,environmental,and energy applications.
基金National Natural Science Foundation of China(No.52373281)National Energy-Saving and Low-Carbon Materials Production and Application Demonstration Platform Program,China(No.TC220H06N)。
文摘The research,fabrication and development of piezoelectric nanofibrous materials offer effective solutions to the challenges related to energy consumption and non-renewable resources.However,enhancing their electrical output still remains a significant challenge.Here,a strategy of inducing constrained phase separation on single nanofibers via shear force was proposed.Employing electrospinning technology,a polyacrylonitrile/polyvinylidene difluoride(PAN/PVDF)nanofibrous membrane was fabricated in one step,which enabled simultaneous piezoelectric and triboelectric conversion within a single-layer membrane.Each nanofiber contained independent components of PAN and PVDF and exhibited a rough surface.The abundant frictional contact points formed between these heterogeneous components contributed to an enhanced endogenous triboelectric output,showcasing an excellent synergistic effect of piezoelectric and triboelectric response in the nanofibrous membrane.Additionally,the component mass ratio influenced the microstructure,piezoelectric conformation and piezoelectric performance of the PAN/PVDF nanofibrous membranes.Through comprehensive performance comparison,the optimal mass ratio of PAN to PVDF was determined to be 9∶1.The piezoelectric devices made of the optimal PAN/PVDF nanofibrous membranes with rough nanofiber surfaces generated an output voltage of 20 V,which was about 1.8 times that of the smooth one at the same component mass ratio.The strategy of constrained phase separation on the surface of individual nanofibers provides a new approach to enhance the output performance of single-layer piezoelectric nanofibrous materials.
基金supported by the National Natural Science Foundation of China(No.52275191)the Major Program of the National Natural Science Foundation of China for Basic Theory and Key Technology of Tri-Co Robots(No.92248301)the 333 Project of Jiangsu Province and Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX22_3622).
文摘The random nanofiber distribution in traditional electrospun membranes restricts the pressure sensing sensitivity and measurement range of electronic skin.Moreover,current multimodal sensing suffers from issues like overlapping signal outputs and slow response.Herein,a novel electrospinning method is proposed to prepare double-coupled microstructured nanofibrous membranes.Through the effect of high voltage electrostatic field in the electrospinning,the positively charged nanofibers are preferentially attached to the negatively charged foam surface,forming the ordered two-dimensional honey-comb porous nanofibrous membrane with three-dimensional spinous microstructure.Compared with the conventional random porous nanofibrous membrane,the bionic two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructures in the ordered porous nanofibrous membrane endows the electronic skin with significantly improved mechanical properties(maximum tensile strain increased by 77%and fatigue resistance increased by 35%),air permeability(water vapor transmission rate increased by 16%)and sensing properties(pressure sensitivity increased by 276%and detection range increased by 137%).Furthermore,the electronic skin was constructed by means of a conformal composite ionic liquid functionalized nanofibrous membrane,and the real-time and interference-free dualsignal monitoring of pressure and temperature(maxi-mum temperature coefficient of resistance:−0.918°C^(−1))was realized.
基金supported by the National Natural Science Foundation of China(22302110,22375047,22378068)National Key Research and Development Program of China(2022YFB3804905)+1 种基金the Open Project Foundation of Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices,Soochow University(No.KJS2210)High-level Talent Initiative Project at Anhui Agricultural University(rc362401)。
文摘Flexible electronic skin(E-skin)sensors offer innovative solutions for detecting human body signals,enabling human-machine interactions and advancing the development of intelligent robotics.Electrospun nanofibers are particularly wellsuited for E-skin applications due to their exceptional mechanical properties,tunable breathability,and lightweight nature.Nanofiber-based composite materials consist of three-dimensional structures that integrate one-dimensional polymer nanofibers with other functional materials,enabling efficient signal conversion and positioning them as an ideal platform for next-generation intelligent electronics.Here,this review begins with an overview of electrospinning technology,including far-field electrospinning,near-field electrospinning,and melt electrospinning.It also discusses the diverse morphologies of electrospun nanofibers,such as core-shell,porous,hollow,bead,Janus,and ribbon structure,as well as strategies for incorporating functional materials to enhance nanofiber performance.Following this,the article provides a detailed introduction to electrospun nanofiber-based composite materials(i.e.,nanofiber/hydrogel,nanofiber/aerogel,nanofiber/metal),emphasizing their recent advancements in monitoring physical,physiological,body fluid,and multi-signal in human signal detection.Meanwhile,the review explores the development of multimodal sensors capable of responding to diverse stimuli,focusing on innovative strategies for decoupling multiple signals and their state-of-the-art advancements.Finally,current challenges are analyzed,while future prospects for electrospun nanofiber-based composite sensors are outlined.This review aims to advance the design and application of next-generation flexible electronics,fostering breakthroughs in multifunctional sensing and health monitoring technologies.
文摘Nanofiber scaffold has built a bionic microenvironment for bone marrow mesenchymal stem cells by highly simulating the topological structure of natural extracellular matrix.Its ordered fiber network effectively guides the directional migration and spatial arrangement of cells through the mechanical signal transduction mediated by integrin.Surface functionalization can synergistically activate the osteogenic transcription network and significantly enhance the osteogenic differentiation potential of cells.The precise design of scaffold stiffness affects the cell fate choice by regulating the nuclear translocation of mechanical sensitive factors.This triple cooperative strategy of“physical topology-biochemical signal-mechanical microenvironment”effectively overcomes the biological inertia of traditional scaffolds and provides a dynamic and adjustable platform for bone defect repair.Looking forward to the future,breaking through the bottleneck of clinical transformation such as long-term intelligent slow release of functional factors and in situ efficient construction of vascular network is the key to promoting nanofiber scaffolds from basic research to precise bone regeneration treatment.
基金supported by the National Natural Science Foundation of China(No.52173155)the Natural Science Foundation of Jilin Province(Nos.YDZJ202101ZYTS130,YDZJ202101ZYTS059)the Natural Science Foundation of Chongqing(Nos.cstc2021jcyj-msxmX1076,cstc2021jcyj-msxmX0798).
文摘A self-standing dual-electric field synergistic[TiO_(2)/polyvinylidene fluoride(PVDF)]//[g-C3 N4 tube/PVDF]Janus nanofibres(named as[TP]//[CTP]JNs)S-scheme heterostructure piezoelectric photocatalyst is designed and constructed via conjugative electrospinning.Dual-fields of built-in electric fields supplied by S-scheme heterostructure and piezoelectric field formed by PVDF jointly boost separation and transfer of photo-induced charges.As a case study,piezoelectric photocatalytic efficiency of[TP]//[CTP]JNs for tetracycline hydrochloride(TCH)under ultrasonic united with simulated sunlight illumination is 93.35%(40 min),which is 1.39 times of the photocatalytic efficiency(light illumination only)and 5.32 times of piezoelectric catalytic efficiency(applying ultrasonic only),proving the advantages of the synergistic effect of piezoelectric catalysis and photocatalysis on contaminant degradation.The dynamic behaviors of photocatalysis and photo-generated charges are deeply revealed through fs-TA and TRPL decay spectra,and the degradation pathways of antibiotics are reasonably speculated by combining LCMS spectra with Fukui index.By the degradation ability,COMSOL simulation and DFT calculation,the structural advantage of Janus nanofibers is fully verified,and S-scheme charge transfer mechanism is confirmed by combining a series of sound ample experiments with theoretical calculations.Additionally,the construction mechanism of Janus nanofibers is proposed,and corresponding construction technique is established.
文摘Due to some intrinsic functional behavior of alginate, many potential applications in the healthcare industry especially in wound care sector are observed. Many researches have been carried out to develop potential biomedical biocompatible products in different forms from alginate fibres. Alginate nanofibres were prepared from sodium alginate polymer with the presence of poly-(ethylene oxide) (PEO), a small amount of Triton ×100 surfactant. A homogeneous spinning solution was prepared for producing Na-alginate/PEO nanofibers in electrospinning device. Nanofibres were produced by electrospinning from 70:30 and 80:20 Na-alginate/PEO of 4% solution. After a series of trials, the electrospinning parameters were optimized at 16 cm working distance, 0.4 mL/h flow rate and 10.5 kV applied voltage. The results show that the 4 wt% of 70:30 Na-alginate/PEO solution with 0.5 wt% Triton × 100 surfactant yielded smooth and stable electrospinning. The surface morphology of the fibres was investigated using Scanning Electron Microscope (SEM) and found the uniform fibres with an average diameter of 124 nm containing few thick or spindle-like fibres. FTIR investigation identified the chemical structure and molecular changes that occurred in the fibers.
文摘High-repetition-rate femtosecond lasers enable the precise production of nanofoam from a wide range of materials. Here, the laser-based fabrication of nanofoam from silicon, borosilicate glass, sodalime glass, gallium lanthanum sulphide and lithium niobate is demonstrated, where the pore size of the nanofoam is shown to depend strongly on the material used, such that the pore width and nanofibre width appear to increase with density and thermal expansion coefficient of the material. In addition, the patterning of nanofoam on a glass slide, with fabricated pattern pixel resolution of ~35 μm, is demonstrated.
基金the Grant Agency CR for the financial support of Grant Project(No.17-26808S)the support of the Ministry of Education,Youth and Sports of the Czech Republic-Programme NPU I(No.LO1504)
文摘The rheological properties in question are influenced by many factors, ranging from the characteristics of the given polymer or solvent to the flowing conditions. The primary focus of this study is to analyse the rheological behaviour of poly（vinyl butyral）—Mowital B 60 H—（PVB） solutions dissolved in methanol and a blend of these with fumed silica nanoparticles. The preparation of the nanofibrous web and the quality of nanofibres were correlated with the rheology of the polymer solution. It was discerned that drastically intensifying shear viscosity and the elasticity of the solution exerted a negligible effect on the formation of fibres, a finding which has rarely been discussed in the literature. The morphologies and structures of the PVB/silica nanofibrous membranes were investigated by scanning electron microscopy, thermogravimetric analysis and Fourier transform infrared spectroscopy.
文摘Carbon nanofibers have revolutionized nanotechnology due to their potential applications in emerging frontiers of research and industrial sectors. This can be attributed to their superior properties such as higher mechanical strength, unique surface characteristics, and improved adherence that is transmitted into the polymer matrix to form a nanocomposite with improved properties. Polymethyl methacrylate is a common carbon source for the synthesis of carbon nanofibres of its high mechanical strength, thermal stability, and low moisture and water absorbing capacity that allows its products to have several applications. In this work, we report the successful electrospinning of carbon nanofibres from Poly methyl methacrylate and functionalizing the resulting carbon nanofibres. The functionalized carbon nanofibres were analyzed to determine their solubility/dispersion in selected organic solvents, then characterized using Fourier transform infra-red spectroscopy, Raman spectroscopy, scanning electron microscopy combined with Energy dispersive spectroscopy and Thermalgravimetric analysis.
基金financially supported by the National Natural Science Foundation of China(No.81600353)the Career Development Program for Young Teachers in Shenyang Pharmaceutical University
文摘Diabetes is one of the most prevalent diseases in the world with high-mortality and complex complications including diabetic foot ulcer(DFU). It has been reported that the difficulties in repairing the wound related to DFU has much relationship with the wound infection,change of inflammatory responses, lack of extracellular matrix(ECM), and the failure of angiogenesis. Following the development of medical materials and pharmaceutical technology, nanofibers has been developed by electrospinning with huge porosity, excellent humidity absorption, a better oxygen exchange rate, and some antibacterial activities. That is to say, as a potential material, nanofibers must be a wonderful candidate for the DFU treatment with so many benefits. Careful selection of polymers from natural resource and synthetic resource can widen the nanofibrous application. Popular methods applied for the nanofibrous fabrication consist of uniaxial electrospinning and coaxial electrospinning. Furthermore, nanofibers loading chemical, biochemical active pharmaceutical ingredient(API)or even stem cells can be wonderful dosage forms for the treatment of DFU. This review summarizes the present techniques applied in the fabrication of nanofibrous dressing(ND)that utilizes a variety of materials and active agents to offer a better health care for the patients suffering from DFU.
基金the National Natural Science Foundation of China(Nos.51773127,51873115,51803131 and 51803134)the State Key Research Development Programme of China(Nos.2016YFC1103000 and 2018YFC1106400)the Science and Technology Program of Sichuan Province(Nos.2017SZ0011 and 2019YJ0132)。
文摘The adsorption technology has been widely applied in water remediation for contamination removal of dyes and bacteria,by virtue of the advantages of adsorption technology including high efficiency,energy conservation and ease of operation.Simultaneous removal of dyes and bacteria has been realized by some reported materials,but to achieve satisfactory adsorption amounts and rates remain an unmet goal for decades.Herein,a poly(methacrylatoethyl trimethyl ammonium chloride-co-methyl methacrylate)copolymer was synthesized,and then blended with polyethersulfone for the fabrication of nanofibrous membranes via electrospinning for the use of fast and massive removal of dyes and bacteria.Owing to the introduction of abundant quaternary ammonium groups,the maximum adsorption amount for methyl orange was up to 909.8 mg g^(-1).In addition,the modified nanofibrous membranes showed good recyclability,broad applications in severe environments,selective adsorption ability,and excellent dynamic removal performance.Especially,thanks to the abundant functional groups,the membranes showed fast adsorption ability for bacteria through electrostatic interaction.It should be noted that the clearance ratio for Staphylococcus aureus or Escherichia coli by 6 min of static adsorption could reach 93%or 90%for each.Additionally,dynamic removal ratio via filtration with the nanofibrous membranes could reach 99.7%for Staphylococcus aureus or 98.7%for Escherichia coli in 90 s.Therefore,the proposed approach towards the quaternary ammonium modified polyethersulfone nanofibrous membranes creates a new route for ultra-high adsorption capacity and ultra-fast removal rates for dyes and bacteria in water remediation.
基金financially supported by the National Natural Science Foundation of China(Nos.50821062,50673097)CAS Innovation Project(No.2007CB936400)
文摘The acoustical damping property of electrospun polyacrylonitrile （PAN） nanofibrous membranes with different thicknesses and porosities was investigated. The sound absorption coefficients were measured using the impedance tube instrument based on ISO10534-2：1998（E）. Results indicate that the first resonance absorption frequency of nanofibrous membranes shifts to the lower frequency with the increase of the back cavity or the thickness of membranes. Moreover, the sound absorption performance of the perforated pane/ can be greatly improved by combination with a thin layer of PAN nanofibrous membrane. Traditional acoustical damping materials （foam, fiber） coated with nanofibrous membranes have better acoustical performance in the low and medium frequency range than that of acoustical materials alone. All of the results demonstrate the PAN nanofibrous membrane is a suitable candidate for noise reduction.
基金the National Natural Science Foundation of China(Nos.52003179 and 52073190)。
文摘Adsorption and photocatalysis are regarded as two desirable technologies for wastewater remediation,but are still unsatisfactory in removal effect,eco-friendly regeneration and facile reusability.In this study,we developed a composite nanofibrous membrane material with excellent removal performance for organic pollutants based on synergistic adsorption and photocatalysis.A novel boron-doped,nitrogen-deficient graphitic carbon nitride(B-C3N4)photocatalyst as well as an amphiphilic copolymer of methyl methacrylate and acrylic acid(p(MMA-AA))were synthesized respectively,and then used to modify polyethersulfone for the fabrication of composite nanofibrous membrane with improved hydrophilicity,negativelycharge property and enhanced visible light response simultaneously.Subsequently,the synergistic effect of adsorption and photocatalytic degradation for organic pollutants were identified especially and resulted in an excellent removal efficiency even superior to the combination of adsorption and photocatalytic degradation,which could be called a“1+1>2”effect.In addition,the regeneration and reusability,the purification ability for multicomponent wastewater,and the photocatalytic mechanism,were investigated and discussed systematically.In this work,we not only prepared the nanofibrous membrane with synergistic effect of adsorption and photocatalysis,but also provided a versatile approach to design dualfunctional support material to ensure the practical applications of powdery photocatalyst in wastewater treatment.
基金This work was supported by the National Natural Science Foundation of China(Nos.21961132024,51925302,and 52173055)the Ministry of Science and Technology of China(No.2021YFE0105100)the Fundamental Research Funds for the Central Universities and the DHU Distinguished Young Professor Program(No.LZA2020001).
文摘One-dimensional(1D)SiO_(2) nanofibers(SNFs),one of the most popular inorganic nanomaterials,have aroused widespread attention because of their excellent chemical stability,as well as unique optical and thermal characteristics.Electrospinning is a straightforward and versatile method to prepare 1D SNFs with programmable structures,manageable dimensions,and modifiable properties,which hold great potential in many cutting-edge applications including aerospace,nanodevice,and energy.In this review,substantial advances in the structural design,controllable synthesis,and multifunctional applications of electrospun SNFs are highlighted.We begin with a brief introduction to the fundamental principles,available raw materials,and typical apparatus of electrospun SNFs.We then discuss the strategies for preparing SNFs with diverse structures in detail,especially stressing the newly emerging three-dimensional SiO_(2) nanofibrous aerogels.We continue with focus on major breakthroughs about brittleness-to-flexibility transition of SNFs and the means to achieve their mechanical reinforcement.In addition,we showcase recent applications enabled by electrospun SNFs,with particular emphasis on physical protection,health care and water treatment.In the end,we summarize this review and provide some perspectives on the future development direction of electrospun SNFs.
