We reported the earliest cases involving electrostatic spinning synthetic dura substitutes for repairing defects in the spinal dura mater. From June to September 2017, seven patients were treated with electrostatic sp...We reported the earliest cases involving electrostatic spinning synthetic dura substitutes for repairing defects in the spinal dura mater. From June to September 2017, seven patients were treated with electrostatic spinning synthetic dura substitute. The laminotomy was performed for all the patients, and the cancers were resected, then the electrostatic spinning synthetic dura substitute made of polylactic acid ReDuraTM. All of the patients had no complications and might be the ideal promising alternative for repairing the spinal dura mater.展开更多
Barium ferrite micro-/nanofibers with special morphology,nanowires with diameters of 100 nm,nanoribbons with diameters of 1μm,and nanotubes with outer diameter of about 300 nm while inner diameter of 100 nm were succ...Barium ferrite micro-/nanofibers with special morphology,nanowires with diameters of 100 nm,nanoribbons with diameters of 1μm,and nanotubes with outer diameter of about 300 nm while inner diameter of 100 nm were successfully prepared via electrospinning using different solvents（dimethyl formamide（DMF）,solutions of deionized water and ethyl alcohol,and solutions of deionized water and acetic acid,respectively）.The barium ferrite micro-/nanofibers were characterized by scanning electron microscope（SEM）,X-ray diffraction analysis（XRD）,and vibration sample magnetometer（VSM）.The results demonstrate that the pure BaFe12O19 ferrite phase is successfully formed.And the SEM results show excellent morphologies.The magnetic hysteresis loops demonstrate that their magnetic properties are quite different with different morphologies.The specific saturation magnetization is approximately the same（46.12-49.17 A·m^2·kg^-1）,but the coercivity of the BaFe12O19 increases from wires（190.08 kA·m^-1）,ribbons（224.16 kA·m^-1） to tubes（258.88 kA·m^-1）.展开更多
Barium ferrite micro/nano fibers were successfully prepared via the electrostatic spinning by using dimethyl formamide（DMF） as the solvent, and poly vinyl pyrrolidone（PVP） as the spinning auxiliaries. Effects of s...Barium ferrite micro/nano fibers were successfully prepared via the electrostatic spinning by using dimethyl formamide（DMF） as the solvent, and poly vinyl pyrrolidone（PVP） as the spinning auxiliaries. Effects of strontium substitution on the structure, morphology, and magnetic properties were investigated by scanning electron microscope（SEM）, X-ray diffraction analysis（XRD）, and vibration sample magnetometer（VSM）. XRD patterns of the samples confirm that pure barium ferrite fibers form, and the Sr substitution makes the main peaks（110）,（107）, and（114） move to right slightly. Also, the FE-SEM images show that the Sr substituted fibers can keep complete fibrous morphology. Moreover, the VSM results demonstrate that the saturation magnetization can reach 56.7 emu/g when the fibers are calcined at 800℃.展开更多
Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly urgent.Multi-component interface engineering is con...Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly urgent.Multi-component interface engineering is considered an effective means to achieve high-efficiency EMW absorption.However,interface modulation engineering has not been fully discussed and has great potential in the field of EMW absorption.In this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal reduction.By utilizing the different properties of different substances,rich heterogeneous interfaces are constructed.This effectively promotes charge transfer and enhances interfacial polarization and conduction loss.The prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy resin.The minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 GHz.Moreover,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel surfaces.Therefore,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.展开更多
Cerium oxide(CeO_(2)) has attracted much attention in recent years owing to its reversible switch ability in Ce^(3+)/Ce^(4+)redox to produce improved antioxidation properties for biomedical applications.Here,we report...Cerium oxide(CeO_(2)) has attracted much attention in recent years owing to its reversible switch ability in Ce^(3+)/Ce^(4+)redox to produce improved antioxidation properties for biomedical applications.Here,we report to embed the CeO_(2)nanospheres into the organic polymer network using electrostatic spinning technology to prepare polyvinyl alcohol(PVA)-encapsulated CeO_(2)nanospheres composite nanofibrous membranes(PVA-CeO_(2)) for the first time,which is beneficial to improving the dispersion and biocompatibility of CeO_(2)nanosphere without altering the original antioxidant properties of CeO_(2).Detailed characterization of the as-prepared composite nanofibrous membranes reveals that CeO_(2)was successfully introduced into the PVA fibers with strong interactions,thus enhancing the thermal stability and fracture toughness of the nanoifbers.As a result,PVA-CeO_(2)exhibits superior UV shielding performance,antioxidant performance and bacteriostatic performance.Meaningfully,PVA-CeO_(2)has strong absorbance in both UVA and UVB bands when the CeO_(2)concentration in the nanoifber membrane reaches 1.5 wt%,and shows an excellent scavenging effect on the 2,2-diphenyl-1-picrylhydrazyl(DPPH)radicals with a scavenging rate of 86.52%.Moreover,the Kirby-Bauer(K-B) method of agar diffusion test further confirms that PVA-CeO_(2)has antimicrobial ability against three types of representative strains,including Gram-positive bacteria(Staphylococcus aureus),Gram-negative bacteria(Escherichia coli) and fungi(Candida albicans).Importantly,no obvious cytotoxicity is observed for PVA-CeO_(2)even though the amount of embedded CeO_(2)nanosphere reaches as high as 1.5 wt%.This study reveals new avenues for improving the future smart design of CeO_(2)-based nanoifber membrane composite materials for biological antioxidants.展开更多
Lanthanum ferrite is a representative perovskite-structured rare earth-based bimetallic oxide,which has been widely studied in magnetic materials,sensors,catalysts and batteries.Herein,we designed and prepared polyoxo...Lanthanum ferrite is a representative perovskite-structured rare earth-based bimetallic oxide,which has been widely studied in magnetic materials,sensors,catalysts and batteries.Herein,we designed and prepared polyoxometalate electron acceptor decorated LaFeO_(3)gas-sensitive composite materials with one-dimensional nanoribbons morphology by electrospinning.The effects of different mass fraction of Keggin type phosphotungstic acid(PW_(12)) on the gas-sensitive properties of LaFeO_(3)nanoribbons were investigated.The results show that the response value of LaFeO_(3)/PW_(12)sensor to acetone gas first increases and then decreases with the increase of PW_(12)content.The LaFeO_(3)/3%PW_(12)sensor exhibits a maximum response of 3.35-5 ppm acetone at 250℃,a 2.6 times increase in response value and a 90℃reduction in operating temperature compared to pure LaFeO_(3)nanoribbons.The LaFeO_(3)/3%PW_(12)sensor exhibits good linear relation in ppb-level concentrations and the lowest detection concentration is100 ppb.The sensors also show good repeatability in 6 tests and excellent long-term stability in 30 d.The improvement of the gas sensitive properties of the composite can be attributed to the synergistic effect between the two components.As an electron acceptor,PW_(12) promotes carrier migration between PW_(12)and LaFeO_(3),thereby improving the gas sensing performance of LaFeO_(3).This work promotes the practical application of polyoxometalate to promote rare earth-based gas sensitive materials in sensing field.展开更多
With the rapid development of 5G technology and the interconnection of industrial production,electro-magnetic pollution has become a serious problem.Achieving lightweight and controllable loads of ab-sorbers while obt...With the rapid development of 5G technology and the interconnection of industrial production,electro-magnetic pollution has become a serious problem.Achieving lightweight and controllable loads of ab-sorbers while obtaining corrosion-resistant absorbers with high electromagnetic response properties is still considered a huge challenge.In this work,carbon fiber with a multichannel hollow structure is ob-tained by PAN/PS hybrid electrospinning and subsequent high-temperature roasting process.The spatial structure inside the carbon fiber plays an active role in optimizing the impedance matching character-istics of the absorber.In addition,bimetallic metal-organic frameworks(MOFs)derivatives are obtained by a precisely controlled ion exchange as well as a high-temperature gas-phase selenization process.The resulting introduction of a non-homogeneous interface induces interfacial polarization and improves the absorption behavior of the absorber.The analysis of the experimental results shows that the electro-magnetic wave(EMW)absorption performance can be effectively enhanced due to the mechanisms of interface polarization and dipole polarization.The prepared NiSe/ZnSe/MHCFs composite can obtain ex-cellent EMW absorption properties in C,X,and Ku bands by adjusting the thickness.Structural design and component modulation play a crucial role in realizing the strong absorption and wide bandwidth of the absorber.Radar cross-section calculations indicate that NiSe/ZnSe/MHCFs have tremendous potential in practical military stealth technology.And the prepared composite coating can provide periodic corrosion resistance to Q235 steel sheet when dealing with complex and extreme environments.展开更多
The development of wearable multifunctional electromagnetic protective fabrics with multifunctional,low cost,and high efficiency remains a challenge.Here,inspired by the unique flower branch shape of“Thunberg’s mead...The development of wearable multifunctional electromagnetic protective fabrics with multifunctional,low cost,and high efficiency remains a challenge.Here,inspired by the unique flower branch shape of“Thunberg’s meadowsweet”in nature,a nanofibrous composite membrane with hierarchical structure was constructed.Integrating sophisticated 0D@2D@1D hierarchical structures with multiple heterointerfaces can fully unleash the multifunctional application potential of composite membrane.The targeted induction method was used to precisely regulate the formation site and morphology of the metal–organic framework precursor,and intelligently integrate multiple heterostructures to enhance dielectric polarization,which improves the impedance matching and loss mechanisms of the electromagnetic wave absorbing materials.Due to the synergistic enhancement of electrospinning-derived carbon nanofiber“stems”,MOF-derived carbon nanosheet“petals”and transition metal selenide nano-particle“stamens”,the CoxSey/NiSe@CNSs@CNFs(CNCC)composite membrane obtains a minimum reflection loss value(RL_(min))of-68.40 dB at 2.6 mm and a maximum effective absorption bandwidth(EAB)of 8.88 GHz at a thin thickness of 2.0 mm with a filling amount of only 5 wt%.In addition,the multi-component and hierarchical heterostructure endow the fibrous membrane with excellent flexibility,water resistance,thermal management,and other multifunctional properties.This work provides unique perspectives for the precise design and rational application of multifunctional fabrics.展开更多
Application of novel radio technologies and equip-ment inevitably leads to electromagnetic pollution.One-dimensional polymer-based composite membrane structures have been shown to be an effective strategy to obtain hi...Application of novel radio technologies and equip-ment inevitably leads to electromagnetic pollution.One-dimensional polymer-based composite membrane structures have been shown to be an effective strategy to obtain high-performance microwave absorbers.Herein,we reported a one-dimensional N-doped carbon nanofibers material which encapsulated the hollow Co_(3)SnC_(0.7) nano-cubes in the fiber lumen by electrospinning.Space charge stacking formed between nanoparticles can be channeled by longitudinal fibrous structures.The dielectric constant of the fibers is highly related to the carbonization temperature,and the great impedance matching can be achieved by synergetic effect between Co_(3)SnC_(0.7) and carbon network.At 800℃,the necklace-like Co_(3)SnC_(0.7)/CNF with 5%low load achieves an excellent RL value of−51.2 dB at 2.3 mm and the effective absorption bandwidth of 7.44 GHz with matching thickness of 2.5 mm.The multiple electromagnetic wave(EMW)reflections and interfacial polarization between the fibers and the fibers internal contribute a major effect to attenuating the EMW.These strategies for regulating electromagnetic performance can be expanded to other electromagnetic functional materials which facilitate the development of emerging absorbers.展开更多
Cobalt selenide(CoSe_(2))has become a promising anode material for sodium-ion batteries(SIBs)due to its stable chemical properties,environmental friendliness,and high theoretical capacity.However,the undesirable rate ...Cobalt selenide(CoSe_(2))has become a promising anode material for sodium-ion batteries(SIBs)due to its stable chemical properties,environmental friendliness,and high theoretical capacity.However,the undesirable rate capacity and cycle stability of the anode materials largely limit its applications for SIBs due to the relatively low electronic conductivity and huge volume change during the Na+insertion/extraction.In this study,electrostatic spinning combined with a wet chemical method is employed to synthesize coral-like composite material(CNF@c-CoSe_(2)/C),which is composed of CoSe_(2)/carbon nanosheet arrays(CoSe_(2)/C)and carbon nanofibers(CNFs).CoSe_(2)/C nanoflakes derived from metal-organic frameworks(MOFs)with high surface area and the porous structure can inhibit the pulverization and amorphization of CoSe_(2) during charge and discharge processes,thus significantly keeping the stability of the microstructure.CNF can limit the overgrowth of nanosheets and serve as a conductive skeleton.Compared to two-dimensional CoSe_(2)/C nanoflakes and pure CoSe_(2) nanoparticles,the composite can expose more active sites and effectively accelerate the diffusion of Na+,which displays enhanced rate capability(266.5 mAh·g^(-1) at 5.0 A·g^(-1))and cycling stability(268.3 mAh·g^(-1) after 100 cycles at 1.0 A·g^(-1)).Moreover,the rational preparation strategy for metal selenide-based heterostructure material presents a new way for high-performance SIB s.展开更多
Although lithium-sulfur batteries(LSBs)exhibit high theoretical energy density,their practical application is hindered by poor conductivity of the sulfur cathode,the shuttle effect,and the irreversible deposition of L...Although lithium-sulfur batteries(LSBs)exhibit high theoretical energy density,their practical application is hindered by poor conductivity of the sulfur cathode,the shuttle effect,and the irreversible deposition of Li_(2)S.To address these issues,a novel composite,using electrospinning technology,consisting of Fe_(3)Se_(4)and porous nitrogen-doped carbon nanofibers was designed for the interlayer of LSBs.The porous carbon nanofiber structure facilitates the transport of ions and electrons,while the Fe_(3)Se_(4)material adsorbs lithium polysulfides(LiPSs)and accelerates its catalytic conversion process.Furthermore,the Fe_(3)Se_(4)material interacts with soluble LiPSs to generate a new polysulfide intermediate,Li_(x)FeS_(y)complex,which changes the electrochemical reaction pathway and facilitates the three-dimensional deposition of Li_(2)S,enhancing the reversibility of LSBs.The designed LSB demonstrates a high specific capacity of1529.6 mA h g^(-1)in the first cycle at 0.2 C.The rate performance is also excellent,maintaining an ultra-high specific capacity of 779.7 mA h g^(-1)at a high rate of 8 C.This investigation explores the mechanism of the interaction between the interlayer and LiPSs,and provides a new strategy to regulate the reaction kinetics and Li_(2)S deposition in LSBs.展开更多
To improve the selective separation performance of silica nanofibers(SiO_(2)NFs)for cesium ions(Cs+)and overcome the defects of Prussian blue nanoparticles(PB NPs),PB/SiO_(2)-NH_(2)NFs were prepared to remove Cs^(+)fr...To improve the selective separation performance of silica nanofibers(SiO_(2)NFs)for cesium ions(Cs+)and overcome the defects of Prussian blue nanoparticles(PB NPs),PB/SiO_(2)-NH_(2)NFs were prepared to remove Cs^(+)from water.Among them,3-aminopropyltriethoxysilane(APTES)underwent an alkylation reaction with SiO_(2),resulting in the formation of a dense Si-O-Si network structure that decorated the surface of SiO_(2)NFs.Meanwhile,the amino functional groups in APTES combined with Fe3+and then reacted with Fe2+to form PB NPs,which anchored firmly on the aminoated SiO_(2)NFs surface.In our experiment,the maxi-mumadsorption capacity of PB/SiO_(2)-NH_(2)NFs was 111.38 mg/g,which was 31.5mg/g higher than that of SiO_(2)NFs.At the same time,after the fifth cycle,the removal rate of Cs^(+)by PB/SiO_(2)-NH_(2)NFs adsorbent was 75.36%±3.69%.In addition,the adsorption isotherms and adsorption kinetics of PB/SiO_(2)-NH_(2)NFs were combined with the Freundlich model and the quasi-two-stage fitting model,respectively.Further mechanism analysis showed that the bond between PB/SiO_(2)-NH_(2)NFs and Cs^(+)was mainly a synergistic action of ion exchange,electrostatic adsorption and membrane separation.展开更多
Flexible strain sensor has attracted much attention because of its potential application in human motion detection.In this work,the prepared strain sensor was obtained by encapsulating electrospun carbonized sponge(CS...Flexible strain sensor has attracted much attention because of its potential application in human motion detection.In this work,the prepared strain sensor was obtained by encapsulating electrospun carbonized sponge(CS)with room temperature vulcanized silicone rubber(RTVS).In this paper,the formation mechanism of conductive sponge was studied.Based on the combination of carbonized sponge and RTVS,the strain sensing mechanism and piezoresistive properties are discussed.After research and testing,the CS/RTVS flexible strain sensor has excellent fast response speed and stability,and the maximum strain coefficient of the sensor is 136.27.In this study,the self-developed CS/RTVS sensor was used to monitor the movements of the wrist joint,arm elbow joint and fingers in real time.Research experiments show that CS/RTVS flexible strain sensor has good application prospects in the field of human motion monitoring.展开更多
Magnetic metal has broad application prospects in the field of electromagnetic wave(EMW)absorption due to its excellent dielectric and magnetic properties.However,high density and poor chemical stability constrain the...Magnetic metal has broad application prospects in the field of electromagnetic wave(EMW)absorption due to its excellent dielectric and magnetic properties.However,high density and poor chemical stability constrain their development potential.The combination of magnetic metals with other lightweight carbon materials is an effective solution.In this work,magnetic nanoparticle fiber composites were prepared by electrostatic spinning and high-temperature annealing processes.By adjusting the preparation process and annealing temperature,Co/Co7 Fe_(3)/CF-800 fiber composites containing double-shell hollow structured nanocubes were cleverly synthesized.The material is mixed with paraffin wax and has a minimum reflection loss(RL)of-52.14 dB and a maximum effective absorption bandwidth(EAB)of 6.16 GHz at a load of 10 wt%.By analyzing the electromagnetic parameters of the material,it was demonstrated that the material absorbs EMW through the synergistic effect of dielectric and magnetic losses.Electrochemical testing in a simulated seawater environment demonstrated that the material also has a degree of self-anticorrosion capability.This work provides new strategies for designing materials with excellent electromagnetic wave absorption and self-anticorrosion properties.展开更多
Herein,a unique mesoporous heterostructure(average pore size:15 nm)cobalt disulfide/carbon nanofibers(CoS_(2)/PCNFs)composite with excellent hydrophilicity(contact angle:23.5°)is prepared using polyethylene glyco...Herein,a unique mesoporous heterostructure(average pore size:15 nm)cobalt disulfide/carbon nanofibers(CoS_(2)/PCNFs)composite with excellent hydrophilicity(contact angle:23.5°)is prepared using polyethylene glycol(PEG)as a pore-forming agent.The CoS_(2)/PCNF electrode exhibits excellent cycle stability(95.2%of initial specific capacitance at 10 A·g^(-1)after 8000 cycles),good rate performance(46.5%at 10 A·g^(-1)),and high specific capacity(86.1 mAh·g^(-1)at 1 A·g^(-1),about 688.8 F·g^(-1)at 1 A·g^(-1)).Density functional theory(DFT)simulation elucidates that CoS_(2)tends to transfer substantial charges to CNF.As the center of positive charge,CoS_(2)is more likely to capture negative ions in the electrolyte,thus accelerating the ion diffusion process.The excellent properties of the electrode material can not only accelerate the electrochemical reaction kinetics,but also provide abundant redox-active sites and a high Faradaic capacity for the entire electrode due to the synergistic contributions of CoS_(2)nanoparticles,mesoporous heterostructure of PCNF,and admirable hydrophilicity of the composite material.A CoS_(2)/PCNF-0.25//AC(AC:activated carbon)asymmetric supercapacitor is assembled using CoS_(2)/PCNF-0.25 as the positive electrode and AC as the negative electrode,which possesses a high energy density(35.5 Wh·kg^(-1)at a power density of 824 W·kg^(-1))and superior cycling stability(maintaining over 98%of initial capacitance after 2000 cycles).In addition,the unique CoS_(2)/PCNF electrode is expected to be widely used in other electrochemical energy storage devices,such as lithium-ion batteries,sodium-ion batteries,lithium-sulfur batteries,etc.展开更多
Although many superwetting materials have been designed for the treatment of oil-containing wastewater,separation strategies for oil-in-water systems containing bacteria have rarely been reported.Herein,poly(vinyliden...Although many superwetting materials have been designed for the treatment of oil-containing wastewater,separation strategies for oil-in-water systems containing bacteria have rarely been reported.Herein,poly(vinylidene difluoride)-and poly(lactic acid)-blended fibrous membranes loaded with silver and copper oxide nanoparticles were successfully prepared by a two-step method of electrostatic spinning and liquid-phase synthesis.The product membrane showed excellent super-oleophilic properties in air and hydrophobicity under oil.It could separate water-in-oil emulsion systems containing surfactants with an efficiency above90%.More importantly,the nanoparticle-loaded fibers were characterized by material degradability and slowly released ions.The fibers exhibited excellent antibacterial activities against both gram-positive and-negative bacteria.This work provides a feasible strategy for water-in-oil emulsion separation and bacterial treatment of wastewater.展开更多
文摘We reported the earliest cases involving electrostatic spinning synthetic dura substitutes for repairing defects in the spinal dura mater. From June to September 2017, seven patients were treated with electrostatic spinning synthetic dura substitute. The laminotomy was performed for all the patients, and the cancers were resected, then the electrostatic spinning synthetic dura substitute made of polylactic acid ReDuraTM. All of the patients had no complications and might be the ideal promising alternative for repairing the spinal dura mater.
基金financially supported by the National Natural Science Foundation of China(No.51172131)
文摘Barium ferrite micro-/nanofibers with special morphology,nanowires with diameters of 100 nm,nanoribbons with diameters of 1μm,and nanotubes with outer diameter of about 300 nm while inner diameter of 100 nm were successfully prepared via electrospinning using different solvents（dimethyl formamide（DMF）,solutions of deionized water and ethyl alcohol,and solutions of deionized water and acetic acid,respectively）.The barium ferrite micro-/nanofibers were characterized by scanning electron microscope（SEM）,X-ray diffraction analysis（XRD）,and vibration sample magnetometer（VSM）.The results demonstrate that the pure BaFe12O19 ferrite phase is successfully formed.And the SEM results show excellent morphologies.The magnetic hysteresis loops demonstrate that their magnetic properties are quite different with different morphologies.The specific saturation magnetization is approximately the same（46.12-49.17 A·m^2·kg^-1）,but the coercivity of the BaFe12O19 increases from wires（190.08 kA·m^-1）,ribbons（224.16 kA·m^-1） to tubes（258.88 kA·m^-1）.
基金Funded by the Qilu Program in Shandong University and the Natural Science Foundation of Shandong Province(ZR2014EMM001)
文摘Barium ferrite micro/nano fibers were successfully prepared via the electrostatic spinning by using dimethyl formamide（DMF） as the solvent, and poly vinyl pyrrolidone（PVP） as the spinning auxiliaries. Effects of strontium substitution on the structure, morphology, and magnetic properties were investigated by scanning electron microscope（SEM）, X-ray diffraction analysis（XRD）, and vibration sample magnetometer（VSM）. XRD patterns of the samples confirm that pure barium ferrite fibers form, and the Sr substitution makes the main peaks（110）,（107）, and（114） move to right slightly. Also, the FE-SEM images show that the Sr substituted fibers can keep complete fibrous morphology. Moreover, the VSM results demonstrate that the saturation magnetization can reach 56.7 emu/g when the fibers are calcined at 800℃.
基金financially supported by the National Natural Science Foundation of China(No.52377026 and No.52301192)Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)+4 种基金Postdoctoral Fellowship Program of CPSF under Grant Number(No.GZB20240327)Shandong Postdoctoral Science Foundation(No.SDCXZG-202400275)Qingdao Postdoctoral Application Research Project(No.QDBSH20240102023)China Postdoctoral Science Foundation(No.2024M751563)the Qingchuang Talents Induction Program of Shandong Higher Education Institution(Research and Innovation Team of Structural-Functional Polymer Composites).
文摘Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly urgent.Multi-component interface engineering is considered an effective means to achieve high-efficiency EMW absorption.However,interface modulation engineering has not been fully discussed and has great potential in the field of EMW absorption.In this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal reduction.By utilizing the different properties of different substances,rich heterogeneous interfaces are constructed.This effectively promotes charge transfer and enhances interfacial polarization and conduction loss.The prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy resin.The minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 GHz.Moreover,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel surfaces.Therefore,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.
基金Project supported by the National Natural Science Foundation of China (22301012)the R&D Program of Beijing Municipal Education Commission (KM202310011005)。
文摘Cerium oxide(CeO_(2)) has attracted much attention in recent years owing to its reversible switch ability in Ce^(3+)/Ce^(4+)redox to produce improved antioxidation properties for biomedical applications.Here,we report to embed the CeO_(2)nanospheres into the organic polymer network using electrostatic spinning technology to prepare polyvinyl alcohol(PVA)-encapsulated CeO_(2)nanospheres composite nanofibrous membranes(PVA-CeO_(2)) for the first time,which is beneficial to improving the dispersion and biocompatibility of CeO_(2)nanosphere without altering the original antioxidant properties of CeO_(2).Detailed characterization of the as-prepared composite nanofibrous membranes reveals that CeO_(2)was successfully introduced into the PVA fibers with strong interactions,thus enhancing the thermal stability and fracture toughness of the nanoifbers.As a result,PVA-CeO_(2)exhibits superior UV shielding performance,antioxidant performance and bacteriostatic performance.Meaningfully,PVA-CeO_(2)has strong absorbance in both UVA and UVB bands when the CeO_(2)concentration in the nanoifber membrane reaches 1.5 wt%,and shows an excellent scavenging effect on the 2,2-diphenyl-1-picrylhydrazyl(DPPH)radicals with a scavenging rate of 86.52%.Moreover,the Kirby-Bauer(K-B) method of agar diffusion test further confirms that PVA-CeO_(2)has antimicrobial ability against three types of representative strains,including Gram-positive bacteria(Staphylococcus aureus),Gram-negative bacteria(Escherichia coli) and fungi(Candida albicans).Importantly,no obvious cytotoxicity is observed for PVA-CeO_(2)even though the amount of embedded CeO_(2)nanosphere reaches as high as 1.5 wt%.This study reveals new avenues for improving the future smart design of CeO_(2)-based nanoifber membrane composite materials for biological antioxidants.
基金Project supported by the China Postdoctoral Science Foundation (2023M731268)National Natural Science Foundation of China (51902029)Young Elite Scientists Sponsorship Program by CAST (2022QNRC001)。
文摘Lanthanum ferrite is a representative perovskite-structured rare earth-based bimetallic oxide,which has been widely studied in magnetic materials,sensors,catalysts and batteries.Herein,we designed and prepared polyoxometalate electron acceptor decorated LaFeO_(3)gas-sensitive composite materials with one-dimensional nanoribbons morphology by electrospinning.The effects of different mass fraction of Keggin type phosphotungstic acid(PW_(12)) on the gas-sensitive properties of LaFeO_(3)nanoribbons were investigated.The results show that the response value of LaFeO_(3)/PW_(12)sensor to acetone gas first increases and then decreases with the increase of PW_(12)content.The LaFeO_(3)/3%PW_(12)sensor exhibits a maximum response of 3.35-5 ppm acetone at 250℃,a 2.6 times increase in response value and a 90℃reduction in operating temperature compared to pure LaFeO_(3)nanoribbons.The LaFeO_(3)/3%PW_(12)sensor exhibits good linear relation in ppb-level concentrations and the lowest detection concentration is100 ppb.The sensors also show good repeatability in 6 tests and excellent long-term stability in 30 d.The improvement of the gas sensitive properties of the composite can be attributed to the synergistic effect between the two components.As an electron acceptor,PW_(12) promotes carrier migration between PW_(12)and LaFeO_(3),thereby improving the gas sensing performance of LaFeO_(3).This work promotes the practical application of polyoxometalate to promote rare earth-based gas sensitive materials in sensing field.
基金supported by the National Natural Sci-ence Foundation of China(Nos.52377026 and 52301192)Tais-han Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)+4 种基金Postdoctoral Fellowship Program of CPSF(No.GZB20240327)Shandong Postdoctoral Science Foundation(No.SDCX-ZG-202400275)Qingdao Postdoctoral Application Re-search Project(No.QDBSH20240102023)China Postdoctoral Sci-ence Foundation(No.2024M751563)the Qingchuang Talents Induction Program of Shandong Higher Education Institution(Re-search and Innovation Team of Structural-Functional Polymer Composites).
文摘With the rapid development of 5G technology and the interconnection of industrial production,electro-magnetic pollution has become a serious problem.Achieving lightweight and controllable loads of ab-sorbers while obtaining corrosion-resistant absorbers with high electromagnetic response properties is still considered a huge challenge.In this work,carbon fiber with a multichannel hollow structure is ob-tained by PAN/PS hybrid electrospinning and subsequent high-temperature roasting process.The spatial structure inside the carbon fiber plays an active role in optimizing the impedance matching character-istics of the absorber.In addition,bimetallic metal-organic frameworks(MOFs)derivatives are obtained by a precisely controlled ion exchange as well as a high-temperature gas-phase selenization process.The resulting introduction of a non-homogeneous interface induces interfacial polarization and improves the absorption behavior of the absorber.The analysis of the experimental results shows that the electro-magnetic wave(EMW)absorption performance can be effectively enhanced due to the mechanisms of interface polarization and dipole polarization.The prepared NiSe/ZnSe/MHCFs composite can obtain ex-cellent EMW absorption properties in C,X,and Ku bands by adjusting the thickness.Structural design and component modulation play a crucial role in realizing the strong absorption and wide bandwidth of the absorber.Radar cross-section calculations indicate that NiSe/ZnSe/MHCFs have tremendous potential in practical military stealth technology.And the prepared composite coating can provide periodic corrosion resistance to Q235 steel sheet when dealing with complex and extreme environments.
基金supported by the National Natural Science Foundation of China(No.51407134,No.52002196)Natural Science Foundation of Shandong Province(No.ZR2019YQ24,No.ZR2020QF084)+2 种基金Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)the Qingchuang Talents Induction Program of Shandong Higher Education Institution(Research and Innovation Team of Structural-Functional Polymer Composites)Special Financial of Shandong Province(Structural Design of Highefficiency Electromagnetic Wave-absorbing Composite Materials and Construction of Shandong Provincial Talent Teams(No.37000022P990304116449)).
文摘The development of wearable multifunctional electromagnetic protective fabrics with multifunctional,low cost,and high efficiency remains a challenge.Here,inspired by the unique flower branch shape of“Thunberg’s meadowsweet”in nature,a nanofibrous composite membrane with hierarchical structure was constructed.Integrating sophisticated 0D@2D@1D hierarchical structures with multiple heterointerfaces can fully unleash the multifunctional application potential of composite membrane.The targeted induction method was used to precisely regulate the formation site and morphology of the metal–organic framework precursor,and intelligently integrate multiple heterostructures to enhance dielectric polarization,which improves the impedance matching and loss mechanisms of the electromagnetic wave absorbing materials.Due to the synergistic enhancement of electrospinning-derived carbon nanofiber“stems”,MOF-derived carbon nanosheet“petals”and transition metal selenide nano-particle“stamens”,the CoxSey/NiSe@CNSs@CNFs(CNCC)composite membrane obtains a minimum reflection loss value(RL_(min))of-68.40 dB at 2.6 mm and a maximum effective absorption bandwidth(EAB)of 8.88 GHz at a thin thickness of 2.0 mm with a filling amount of only 5 wt%.In addition,the multi-component and hierarchical heterostructure endow the fibrous membrane with excellent flexibility,water resistance,thermal management,and other multifunctional properties.This work provides unique perspectives for the precise design and rational application of multifunctional fabrics.
基金financially supported by the Natural Science Foundation of Shandong Province (No. ZR2019YQ24)Taishan Scholars and Young Experts Program of Shandong Province (No.tsqn202103057)+1 种基金the Qingchuang Talents Induction Program of Shandong Higher Education Institution (Research and Innovation Team of Structural-Functional Polymer Composites)Special Financial of Shandong Province (Structural Design of High-efficiency Electromagnetic Wave-absorbing Composite Materials and Construction of Shandong Provincial Talent Teams)
文摘Application of novel radio technologies and equip-ment inevitably leads to electromagnetic pollution.One-dimensional polymer-based composite membrane structures have been shown to be an effective strategy to obtain high-performance microwave absorbers.Herein,we reported a one-dimensional N-doped carbon nanofibers material which encapsulated the hollow Co_(3)SnC_(0.7) nano-cubes in the fiber lumen by electrospinning.Space charge stacking formed between nanoparticles can be channeled by longitudinal fibrous structures.The dielectric constant of the fibers is highly related to the carbonization temperature,and the great impedance matching can be achieved by synergetic effect between Co_(3)SnC_(0.7) and carbon network.At 800℃,the necklace-like Co_(3)SnC_(0.7)/CNF with 5%low load achieves an excellent RL value of−51.2 dB at 2.3 mm and the effective absorption bandwidth of 7.44 GHz with matching thickness of 2.5 mm.The multiple electromagnetic wave(EMW)reflections and interfacial polarization between the fibers and the fibers internal contribute a major effect to attenuating the EMW.These strategies for regulating electromagnetic performance can be expanded to other electromagnetic functional materials which facilitate the development of emerging absorbers.
基金financially supported by the National Natural Science Foundation of China(Nos.51603092 and 21706103)the Natural Science Foundation of Jiangsu Province(Nos.BK20160537 and BK20170549)China Postdoctoral Science Foundation(No.2019T120393)。
文摘Cobalt selenide(CoSe_(2))has become a promising anode material for sodium-ion batteries(SIBs)due to its stable chemical properties,environmental friendliness,and high theoretical capacity.However,the undesirable rate capacity and cycle stability of the anode materials largely limit its applications for SIBs due to the relatively low electronic conductivity and huge volume change during the Na+insertion/extraction.In this study,electrostatic spinning combined with a wet chemical method is employed to synthesize coral-like composite material(CNF@c-CoSe_(2)/C),which is composed of CoSe_(2)/carbon nanosheet arrays(CoSe_(2)/C)and carbon nanofibers(CNFs).CoSe_(2)/C nanoflakes derived from metal-organic frameworks(MOFs)with high surface area and the porous structure can inhibit the pulverization and amorphization of CoSe_(2) during charge and discharge processes,thus significantly keeping the stability of the microstructure.CNF can limit the overgrowth of nanosheets and serve as a conductive skeleton.Compared to two-dimensional CoSe_(2)/C nanoflakes and pure CoSe_(2) nanoparticles,the composite can expose more active sites and effectively accelerate the diffusion of Na+,which displays enhanced rate capability(266.5 mAh·g^(-1) at 5.0 A·g^(-1))and cycling stability(268.3 mAh·g^(-1) after 100 cycles at 1.0 A·g^(-1)).Moreover,the rational preparation strategy for metal selenide-based heterostructure material presents a new way for high-performance SIB s.
基金financially supported by the National Natural Science Foundation of China(No.22372103)Guangdong Basic and Applied Basic Research Foundation,China(2021A1515010241,2024A1515010032)the Shenzhen Science and Technology Foundation,China(JCYJ20220531103216037)。
文摘Although lithium-sulfur batteries(LSBs)exhibit high theoretical energy density,their practical application is hindered by poor conductivity of the sulfur cathode,the shuttle effect,and the irreversible deposition of Li_(2)S.To address these issues,a novel composite,using electrospinning technology,consisting of Fe_(3)Se_(4)and porous nitrogen-doped carbon nanofibers was designed for the interlayer of LSBs.The porous carbon nanofiber structure facilitates the transport of ions and electrons,while the Fe_(3)Se_(4)material adsorbs lithium polysulfides(LiPSs)and accelerates its catalytic conversion process.Furthermore,the Fe_(3)Se_(4)material interacts with soluble LiPSs to generate a new polysulfide intermediate,Li_(x)FeS_(y)complex,which changes the electrochemical reaction pathway and facilitates the three-dimensional deposition of Li_(2)S,enhancing the reversibility of LSBs.The designed LSB demonstrates a high specific capacity of1529.6 mA h g^(-1)in the first cycle at 0.2 C.The rate performance is also excellent,maintaining an ultra-high specific capacity of 779.7 mA h g^(-1)at a high rate of 8 C.This investigation explores the mechanism of the interaction between the interlayer and LiPSs,and provides a new strategy to regulate the reaction kinetics and Li_(2)S deposition in LSBs.
基金supported by the College Students Extracur-ricular Innovation and Entrepreneurship Fund Project of Changzhou University(No.ZMF21020079)the Natural Sci-ence Fund for Colleges and Universities in Jiangsu Province(No.18KJB610001)+4 种基金the Natural Science Foundation of Jiangsu Province(No.BK20180964)the Science and Technology Project of Changzhou City(No.CJ20210119)the Natural Science Foun-dation of China(No.22075032)the National Key Research and Development Program(No.2021YFC3001104)the Natural Sci-ence Foundation of Xinjiang Uygur Autonomous Region(Nos.2020D01A49,2020D01B25 and 2020D01B26).
文摘To improve the selective separation performance of silica nanofibers(SiO_(2)NFs)for cesium ions(Cs+)and overcome the defects of Prussian blue nanoparticles(PB NPs),PB/SiO_(2)-NH_(2)NFs were prepared to remove Cs^(+)from water.Among them,3-aminopropyltriethoxysilane(APTES)underwent an alkylation reaction with SiO_(2),resulting in the formation of a dense Si-O-Si network structure that decorated the surface of SiO_(2)NFs.Meanwhile,the amino functional groups in APTES combined with Fe3+and then reacted with Fe2+to form PB NPs,which anchored firmly on the aminoated SiO_(2)NFs surface.In our experiment,the maxi-mumadsorption capacity of PB/SiO_(2)-NH_(2)NFs was 111.38 mg/g,which was 31.5mg/g higher than that of SiO_(2)NFs.At the same time,after the fifth cycle,the removal rate of Cs^(+)by PB/SiO_(2)-NH_(2)NFs adsorbent was 75.36%±3.69%.In addition,the adsorption isotherms and adsorption kinetics of PB/SiO_(2)-NH_(2)NFs were combined with the Freundlich model and the quasi-two-stage fitting model,respectively.Further mechanism analysis showed that the bond between PB/SiO_(2)-NH_(2)NFs and Cs^(+)was mainly a synergistic action of ion exchange,electrostatic adsorption and membrane separation.
基金This research is supported by the Science and Technology Department of Jilin Province[20210202128NC]The People’s Republic of China Ministry of Science and Technology[2018YFF0213606-03]Jilin Province Development and Reform Commission[2019C021].
文摘Flexible strain sensor has attracted much attention because of its potential application in human motion detection.In this work,the prepared strain sensor was obtained by encapsulating electrospun carbonized sponge(CS)with room temperature vulcanized silicone rubber(RTVS).In this paper,the formation mechanism of conductive sponge was studied.Based on the combination of carbonized sponge and RTVS,the strain sensing mechanism and piezoresistive properties are discussed.After research and testing,the CS/RTVS flexible strain sensor has excellent fast response speed and stability,and the maximum strain coefficient of the sensor is 136.27.In this study,the self-developed CS/RTVS sensor was used to monitor the movements of the wrist joint,arm elbow joint and fingers in real time.Research experiments show that CS/RTVS flexible strain sensor has good application prospects in the field of human motion monitoring.
基金supported by the National Natural Science Foundation of China(Nos.52377026 and 52301192)Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)the Qingchuang Talents Induction Program of Shandong Higher Education Institution(Research and Innovation Team of Structural-Functional Polymer Composites).
文摘Magnetic metal has broad application prospects in the field of electromagnetic wave(EMW)absorption due to its excellent dielectric and magnetic properties.However,high density and poor chemical stability constrain their development potential.The combination of magnetic metals with other lightweight carbon materials is an effective solution.In this work,magnetic nanoparticle fiber composites were prepared by electrostatic spinning and high-temperature annealing processes.By adjusting the preparation process and annealing temperature,Co/Co7 Fe_(3)/CF-800 fiber composites containing double-shell hollow structured nanocubes were cleverly synthesized.The material is mixed with paraffin wax and has a minimum reflection loss(RL)of-52.14 dB and a maximum effective absorption bandwidth(EAB)of 6.16 GHz at a load of 10 wt%.By analyzing the electromagnetic parameters of the material,it was demonstrated that the material absorbs EMW through the synergistic effect of dielectric and magnetic losses.Electrochemical testing in a simulated seawater environment demonstrated that the material also has a degree of self-anticorrosion capability.This work provides new strategies for designing materials with excellent electromagnetic wave absorption and self-anticorrosion properties.
基金Financial support was received from the National Natural Science Foundation of China(Nos.51976081 and U22A20107)the China Postdoctoral Science Foundation(No.2019T120393)+2 种基金the Jiangsu Province Postdoctoral Foundation(No.2020Z078)the“Grassland Talents”of Inner Mongolia Autonomous Region,the Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(No.NJYT23030)the“Steed Plan High-level Talents”of Inner Mongolia University,and the Carbon Neutralization Research Project(No.STZX202218).
文摘Herein,a unique mesoporous heterostructure(average pore size:15 nm)cobalt disulfide/carbon nanofibers(CoS_(2)/PCNFs)composite with excellent hydrophilicity(contact angle:23.5°)is prepared using polyethylene glycol(PEG)as a pore-forming agent.The CoS_(2)/PCNF electrode exhibits excellent cycle stability(95.2%of initial specific capacitance at 10 A·g^(-1)after 8000 cycles),good rate performance(46.5%at 10 A·g^(-1)),and high specific capacity(86.1 mAh·g^(-1)at 1 A·g^(-1),about 688.8 F·g^(-1)at 1 A·g^(-1)).Density functional theory(DFT)simulation elucidates that CoS_(2)tends to transfer substantial charges to CNF.As the center of positive charge,CoS_(2)is more likely to capture negative ions in the electrolyte,thus accelerating the ion diffusion process.The excellent properties of the electrode material can not only accelerate the electrochemical reaction kinetics,but also provide abundant redox-active sites and a high Faradaic capacity for the entire electrode due to the synergistic contributions of CoS_(2)nanoparticles,mesoporous heterostructure of PCNF,and admirable hydrophilicity of the composite material.A CoS_(2)/PCNF-0.25//AC(AC:activated carbon)asymmetric supercapacitor is assembled using CoS_(2)/PCNF-0.25 as the positive electrode and AC as the negative electrode,which possesses a high energy density(35.5 Wh·kg^(-1)at a power density of 824 W·kg^(-1))and superior cycling stability(maintaining over 98%of initial capacitance after 2000 cycles).In addition,the unique CoS_(2)/PCNF electrode is expected to be widely used in other electrochemical energy storage devices,such as lithium-ion batteries,sodium-ion batteries,lithium-sulfur batteries,etc.
基金supported by the National Key R&D Program of China(Grant No.2020YFC1808401)the National Natural Science Foundation of China(Grant Nos.22078213,21938006,51973148,21776190)+3 种基金the Cutting-Edge Technology Basic Research Project of Jiangsu(Grant No.BK20202012)prospective application research project of Suzhou(Grant No.SYC2022042)water research and technology project of Suzhou(Grant No.2022006)the project supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘Although many superwetting materials have been designed for the treatment of oil-containing wastewater,separation strategies for oil-in-water systems containing bacteria have rarely been reported.Herein,poly(vinylidene difluoride)-and poly(lactic acid)-blended fibrous membranes loaded with silver and copper oxide nanoparticles were successfully prepared by a two-step method of electrostatic spinning and liquid-phase synthesis.The product membrane showed excellent super-oleophilic properties in air and hydrophobicity under oil.It could separate water-in-oil emulsion systems containing surfactants with an efficiency above90%.More importantly,the nanoparticle-loaded fibers were characterized by material degradability and slowly released ions.The fibers exhibited excellent antibacterial activities against both gram-positive and-negative bacteria.This work provides a feasible strategy for water-in-oil emulsion separation and bacterial treatment of wastewater.
