Supercapacitors have huge potential applications in the field of wearable electronic devices,such as flexible displays,flexible biosensors and implantable multimedia devices,due to their high-power density,fast charge...Supercapacitors have huge potential applications in the field of wearable electronic devices,such as flexible displays,flexible biosensors and implantable multimedia devices,due to their high-power density,fast charge-discharge rates,long cycling life,and relatively simple configuration.In this paper,we demonstrated hierarchically porous and continuous reduced graphene oxide-polyacrylonitrile@polyacrylonitrile(rGO-PAN@PAN)coaxial fibers with certain strength,excellent electrochemical performance through coaxial wet spinning and thermal reduction.Coaxial fibers are carbonized at high temperature and have a graded porous structure with a conductivity of 1703 S/m.The areal specific capacitance of the supercapacitor assembled by polyvinyl alcohol/sulfuric acid(PVA/H_(2)SO_(4))gel electrolyte is 11.56 mF/cm^(2),and its energy density reaches 0.21 mW·h/cm3,showing good electrochemical performance.Graphene-based coaxial fibers prepared by wet spinning have a great prospect of application in electronic devices due to their excellent properties.展开更多
Hexagonal boron nitride nanosheets(BNNSs)exhibit remarkable thermal and dielectric properties.However,their self-assembly and alignment in macroscopic forms remain challenging due to the chemical inertness of boron ni...Hexagonal boron nitride nanosheets(BNNSs)exhibit remarkable thermal and dielectric properties.However,their self-assembly and alignment in macroscopic forms remain challenging due to the chemical inertness of boron nitride,thereby limiting their performance in applications such as thermal management.In this study,we present a coaxial wet spinning approach for the fabrication of BNNSs/polymer composite fibers with high nanosheet orientation.The composite fibers were prepared using a superacid-based solvent system and showed a layered structure comprising an aramid core and an aramid/BNNSs sheath.Notably,the coaxial fibers exhibited significantly higher BNNSs alignment compared to uniaxial aramid/BNNSs fibers,primarily due to the additional compressive forces exerted at the core-sheath interface during the hot drawing process.With a BNNSs loading of 60 wt%,the resulting coaxial fibers showed exceptional properties,including an ultrahigh Herman orientation parameter of 0.81,thermal conductivity of 17.2 W m^(-1)K^(-1),and tensile strength of 192.5 MPa.These results surpassed those of uniaxial fibers and previously reported BNNSs composite fibers,making them highly suitable for applications such as wearable thermal management textiles.Our findings present a promising strategy for fabricating high-performance composite fibers based on BNNSs.展开更多
While manganese-based cathodes have been intensively studied for zinc-ion batteries(ZIBs),the limited rate capability and cycle life have always been a difficult problem to be solved.Here,we report a mixed valent mang...While manganese-based cathodes have been intensively studied for zinc-ion batteries(ZIBs),the limited rate capability and cycle life have always been a difficult problem to be solved.Here,we report a mixed valent manganese oxide(MnOx)cathode with superior electrochemical performance,which exhibits a high specific capacity of 450 mA h/g at 0.2 C and a satisfactory specific capacity of 158.3 mA h/g at a high rate of 5 C.The mixed cathode system reduces the charge transfer resistance,and show good surface stability and adsorption properties,so it is beneficial for the storage of Zn^(2+).Meanwhile,coaxial fiber ZIBs(CFZIBs)with splendid flexibility are assembled utilizing the elaborately prepared cathode material.The CFZIBs achieve a reversible capacity of 255.8 m A h/g and the capacity retention rate is as high as 80%after 1000 bending deformations.This study provides new opportunities for designing ZIBs with high performance and high flexibility.展开更多
A newly developed coaxial dielectric barrier discharge reactor with a length of1000 mm at an atmospheric pressure was used for plasma treatment of polyester fiber cord ina roll-to-roll manner. In this reactor, swirlin...A newly developed coaxial dielectric barrier discharge reactor with a length of1000 mm at an atmospheric pressure was used for plasma treatment of polyester fiber cord ina roll-to-roll manner. In this reactor, swirling mixture gases of oxygen of about 1% and argonwith a flow rate of 1.5 L/min to 2.7 L/min ensured the gas usage sparing, discharge uniformityand efficient fiber surface modification. The water contact angle and surface morphology of thetreated fiber were measured. The results show that the surface oxygenation is mainly responsiblefor the wettability improvement of the fiber cord when passing through the plasma zone at a linearspeed of 3 m/min to 8 m/min. The specimens of modified-polyester fiber reinforced rubber compositewere also prepared for the interfacial shear strength tests. Furthermore, the effect of addingoxygen into argon discharge on the fiber surface oxidation was correlated with optical emissionspectroscopy. Finally, the effect of adding oxygen into argon discharge on the kinetic processes ofthe active species generation were also analyzed.展开更多
In this work, the surface modification of poly (1, 4-phenylene-cis-benzobisoxazole) (PBO) fibers by O 2 /Ar coaxial atmospheric dielectric barrier discharge was investigated, as well as the interfacial adhesion proper...In this work, the surface modification of poly (1, 4-phenylene-cis-benzobisoxazole) (PBO) fibers by O 2 /Ar coaxial atmospheric dielectric barrier discharge was investigated, as well as the interfacial adhesion properties of modified PBO fibers/epoxy composites. The results indicated that the contact angle decreased remarkably from 84.7 to 63.5 after 3 min O 2 /Ar plasma treatment. SEM and AFM images showed that the surface of the treated PBO fibers became rather rough. In addition, XPS results suggested that the polar functional group (O=C- O) was introduced on the surface of the treated PBO fiber. The interfacial adhesion test showed that the interfacial shear strength (IFSS) and the interlaminar shear strength (ILSS) increased significantly by 63.54% and 130%, respectively. Moreover, the excellent tensile property of the PBO fibres was well展开更多
Although there has been rapid advancement in piezoelectric sensors,challenges still remain in developing wearable piezoelectric sensors by a one-step,continuous and environmentally friendly method.In this work,a 1D fl...Although there has been rapid advancement in piezoelectric sensors,challenges still remain in developing wearable piezoelectric sensors by a one-step,continuous and environmentally friendly method.In this work,a 1D flexible coaxial piezoelectric fiber was directly fabricated by melt extrusion molding,whose core and sheath layer are respectively slender steel wire(i.e.,electrode)and PVDF(i.e.,piezoelectric layer).Moreover,such 1D flexible coaxial piezoelectric fiber possesses short response time and high sensitivity,which can be used as a selfpowered sensor for bending and vibration sensing.More interestingly,such 1D flexible coaxial piezoelectric fiber(1D-PFs)can be further endowed with 3D helical structure.Moreover,a wearable and washable motion monitoring system can be constructed via braiding such 3D helical piezoelectric fiber(3D-PF)into commercial textiles.This work paves a new way for developing 1D and 3D piezoelectric fibers through a one-step,continuous and environmentally friendly method,showing potential applications in the field of sensing and wearable electronics.展开更多
基金National Natural Science Foundation of China(No.51876115)China Postdoctoral Science Foundation(No.2019M661324)。
文摘Supercapacitors have huge potential applications in the field of wearable electronic devices,such as flexible displays,flexible biosensors and implantable multimedia devices,due to their high-power density,fast charge-discharge rates,long cycling life,and relatively simple configuration.In this paper,we demonstrated hierarchically porous and continuous reduced graphene oxide-polyacrylonitrile@polyacrylonitrile(rGO-PAN@PAN)coaxial fibers with certain strength,excellent electrochemical performance through coaxial wet spinning and thermal reduction.Coaxial fibers are carbonized at high temperature and have a graded porous structure with a conductivity of 1703 S/m.The areal specific capacitance of the supercapacitor assembled by polyvinyl alcohol/sulfuric acid(PVA/H_(2)SO_(4))gel electrolyte is 11.56 mF/cm^(2),and its energy density reaches 0.21 mW·h/cm3,showing good electrochemical performance.Graphene-based coaxial fibers prepared by wet spinning have a great prospect of application in electronic devices due to their excellent properties.
基金This work was supported by the National Key Research and Development Project(Nos.2019YFA0705403,2022YFA1205300)the National Natural Science Foundation of China(No.T2293693)+3 种基金the Guangdong Innovative and Entrepreneurial Research Team Program(No.2017ZT07C341)the Guangdong Basic and Applied Basic Research Foundation(No.2020B0301030002)the Shenzhen Basic Research Project(Nos.WDZC20200824091903001,JSGG20220831105402004)Zhiyuan Xiong thanks the financial support from South China University of Technology.
文摘Hexagonal boron nitride nanosheets(BNNSs)exhibit remarkable thermal and dielectric properties.However,their self-assembly and alignment in macroscopic forms remain challenging due to the chemical inertness of boron nitride,thereby limiting their performance in applications such as thermal management.In this study,we present a coaxial wet spinning approach for the fabrication of BNNSs/polymer composite fibers with high nanosheet orientation.The composite fibers were prepared using a superacid-based solvent system and showed a layered structure comprising an aramid core and an aramid/BNNSs sheath.Notably,the coaxial fibers exhibited significantly higher BNNSs alignment compared to uniaxial aramid/BNNSs fibers,primarily due to the additional compressive forces exerted at the core-sheath interface during the hot drawing process.With a BNNSs loading of 60 wt%,the resulting coaxial fibers showed exceptional properties,including an ultrahigh Herman orientation parameter of 0.81,thermal conductivity of 17.2 W m^(-1)K^(-1),and tensile strength of 192.5 MPa.These results surpassed those of uniaxial fibers and previously reported BNNSs composite fibers,making them highly suitable for applications such as wearable thermal management textiles.Our findings present a promising strategy for fabricating high-performance composite fibers based on BNNSs.
基金National Natural Science Foundation of China with Grant No.21905304Natural Science Foundation of Shandong Province(No.ZR2019BEM031)+1 种基金the Fundamental Research Funds for the Central Universities(Nos.18CX02158A,05Y18030020 and 19CX05001A)the support from the Western University-Soochow University Center for Synchrotron Radiation Research。
文摘While manganese-based cathodes have been intensively studied for zinc-ion batteries(ZIBs),the limited rate capability and cycle life have always been a difficult problem to be solved.Here,we report a mixed valent manganese oxide(MnOx)cathode with superior electrochemical performance,which exhibits a high specific capacity of 450 mA h/g at 0.2 C and a satisfactory specific capacity of 158.3 mA h/g at a high rate of 5 C.The mixed cathode system reduces the charge transfer resistance,and show good surface stability and adsorption properties,so it is beneficial for the storage of Zn^(2+).Meanwhile,coaxial fiber ZIBs(CFZIBs)with splendid flexibility are assembled utilizing the elaborately prepared cathode material.The CFZIBs achieve a reversible capacity of 255.8 m A h/g and the capacity retention rate is as high as 80%after 1000 bending deformations.This study provides new opportunities for designing ZIBs with high performance and high flexibility.
基金supported by National Natural Science Foundation of China (No.11075033)Mehler Engineered Products (Suzhou) Co. Ltd. of China
文摘A newly developed coaxial dielectric barrier discharge reactor with a length of1000 mm at an atmospheric pressure was used for plasma treatment of polyester fiber cord ina roll-to-roll manner. In this reactor, swirling mixture gases of oxygen of about 1% and argonwith a flow rate of 1.5 L/min to 2.7 L/min ensured the gas usage sparing, discharge uniformityand efficient fiber surface modification. The water contact angle and surface morphology of thetreated fiber were measured. The results show that the surface oxygenation is mainly responsiblefor the wettability improvement of the fiber cord when passing through the plasma zone at a linearspeed of 3 m/min to 8 m/min. The specimens of modified-polyester fiber reinforced rubber compositewere also prepared for the interfacial shear strength tests. Furthermore, the effect of addingoxygen into argon discharge on the fiber surface oxidation was correlated with optical emissionspectroscopy. Finally, the effect of adding oxygen into argon discharge on the kinetic processes ofthe active species generation were also analyzed.
基金supported by Shanghai Composite Company and partially by National Natural Science Foundation of China (No.10875146)
文摘In this work, the surface modification of poly (1, 4-phenylene-cis-benzobisoxazole) (PBO) fibers by O 2 /Ar coaxial atmospheric dielectric barrier discharge was investigated, as well as the interfacial adhesion properties of modified PBO fibers/epoxy composites. The results indicated that the contact angle decreased remarkably from 84.7 to 63.5 after 3 min O 2 /Ar plasma treatment. SEM and AFM images showed that the surface of the treated PBO fibers became rather rough. In addition, XPS results suggested that the polar functional group (O=C- O) was introduced on the surface of the treated PBO fiber. The interfacial adhesion test showed that the interfacial shear strength (IFSS) and the interlaminar shear strength (ILSS) increased significantly by 63.54% and 130%, respectively. Moreover, the excellent tensile property of the PBO fibres was well
基金the National Natural Science Foundation of China(No.51873199)Program for Innovative Research Team(in Science and Technology)in University(No.20IRTSTHN002)。
文摘Although there has been rapid advancement in piezoelectric sensors,challenges still remain in developing wearable piezoelectric sensors by a one-step,continuous and environmentally friendly method.In this work,a 1D flexible coaxial piezoelectric fiber was directly fabricated by melt extrusion molding,whose core and sheath layer are respectively slender steel wire(i.e.,electrode)and PVDF(i.e.,piezoelectric layer).Moreover,such 1D flexible coaxial piezoelectric fiber possesses short response time and high sensitivity,which can be used as a selfpowered sensor for bending and vibration sensing.More interestingly,such 1D flexible coaxial piezoelectric fiber(1D-PFs)can be further endowed with 3D helical structure.Moreover,a wearable and washable motion monitoring system can be constructed via braiding such 3D helical piezoelectric fiber(3D-PF)into commercial textiles.This work paves a new way for developing 1D and 3D piezoelectric fibers through a one-step,continuous and environmentally friendly method,showing potential applications in the field of sensing and wearable electronics.
