The electrochemical behaviors (cyclic voltammetry, CV and different pulse voltammetry, DPV) of dopamine (DA) were studied in this paper. The result indicated that the oxidation of dopamine was controlled by diffusion...The electrochemical behaviors (cyclic voltammetry, CV and different pulse voltammetry, DPV) of dopamine (DA) were studied in this paper. The result indicated that the oxidation of dopamine was controlled by diffusion and adsorption simultaneously at nano-gold (NG) modified carbon fiber electrode (CFE). This modified electrode can separate the peak potentials of dopamine and ascorbic acid (AA). The peak current of DA in DPV curve was found to be linearly proportional to the concentration of DA at range of 2.0?0-6～1.5?0-5mol/L and 1.0?0-5～5.0?0-4mol/L, respectively.展开更多
Structural energy storage composites present advantages in simultaneously achieving structural strength and electrochemical properties.Adoption of carbon fiber electrodes and resin structural electrolytes in energy st...Structural energy storage composites present advantages in simultaneously achieving structural strength and electrochemical properties.Adoption of carbon fiber electrodes and resin structural electrolytes in energy storage composite poses challenges in maintaining good mechanical and electrochemical properties at reasonable cost and effort.Here,we report a simple method to fabricate structural supercapacitor using carbon fiber electrodes(modified by Ni-layered double hydroxide(Ni-LDH)and in-situ growth of Co-metal-organic framework(Co-MOF)in a two-step process denoted as Co-MOF/Ni-LDH@CF)and bicontinuous-phase epoxy resin-based structural electrolyte.Co-MOF/Ni-LDH@CF as electrode material exhibits improved specific capacity(42.45 F·g^(-1))and cycle performance(93.3%capacity retention after 1000 cycles)in a three-electrode system.The bicontinuous-phase epoxy resin-based structural electrolyte exhibits an ionic conductivity of 3.27×10^(-4) S·cm^(-1).The fabricated Co-MOF/Ni-LDH@CF/SPE-50 structural supercapacitor has an energy density of 3.21 Wh·kg^(-1) at a power density of 42.25 W·kg^(-1),whilst maintaining tensile strength and modulus of 334.6 MPa and 25.2 GPa.These results show practical potential of employing modified commercial carbon fiber electrodes and epoxy resin-based structural electrolytes in structural energy storage applications.展开更多
A novel sensor for ocean electric field testing has been fabricated by polyacrylonitrile-based on carbon fibers with electro-chemical oxidation.The surface profile characteristics of the carbon fibers were characteriz...A novel sensor for ocean electric field testing has been fabricated by polyacrylonitrile-based on carbon fibers with electro-chemical oxidation.The surface profile characteristics of the carbon fibers were characterized by scanning electron microscope,Fourier transform infrared spectra and contact angle.Cyclic voltammetry and Tafel curves have been used to study its electro-chemical performances.Two identical electrodes in sea water as the electric field sensor will swiftly respond to applied electric field which causes positive and negative ions to move in opposite direction,resulting in a electric potential difference(ΔE).Test result indicates that the offset potential is typically below 1 m V with a drift of 60-170μVd^-1.Typical self noise level is 1.07 nV√Hz^(1/2)@1 Hz.The electric field response indicates that the modified electrode pair shows better response to AC sine signal of amplitude and frequency(5 mV and 1 mHz)respectively than its blank.The electric field response model of the modified electrodes is creatively presented according to its electric double layer capacitance and Faraday pseudo-capacitance.Many advantages of the carbon fiber electric field electrode will make it have potential application prospect.展开更多
Dry-spun Carbon Nanotube(CNT)fibers were surface-modified by atmospheric pressure oxygen plasma functionalization using a well controlled and continuous process.The fibers were characterized by scanning electron micro...Dry-spun Carbon Nanotube(CNT)fibers were surface-modified by atmospheric pressure oxygen plasma functionalization using a well controlled and continuous process.The fibers were characterized by scanning electron microscopy(SEM),Raman spectroscopy,and X-ray Photoelectron Spectroscopy(XPS).It was found from the conducted electrochemical measurements that the functionalized fibers showed a 132.8% increase in specific capacitance compared to non-functionalized fibers.Dye-adsorption test and the obtained Randles-Sevcik plot demonstrated that the oxygen plasma functionalized fibers exhibited increased surface area.It was further established by Brunauer-Emmett-Teller(BET)measurements that the surface area of the CNT fibers was increased from 168.22 m^2/g to 208.01 m^2/g after plasma functionalization.The pore size distribution of the fibers was also altered by this processing.The improved electrochemical data was attributed to enhanced wettability,increased surface area,and the presence of oxygen functional groups,which promoted the capacitance of the fibers.Fiber supercapacitors were fabricated from the oxygen plasma functionalized CNT fiber electrodes using different electrolyte systems.The devices with functionalized electrodes exhibited excellent cyclic stability(93.2% after 4000 cycles),flexibility,bendability,and good energy densities.At 0.5 m A/cm^2,the EMIMBF4 device revealed a specific capacitance,which is 27% and 65%greater than the specific capacitances of devices using EMIMTFSI and H2SO4 electrolytes,respectively.The practiced in this work plasma surface processing can be employed in other applications where fibers,yarns,ribbons,and sheets need to be chemically modified.展开更多
During discharge, appropriately changing the development paths of electron avalanches and increasing the number of initial electrons can effectively inhibit the formation of filamentary discharge. Based on the aforeme...During discharge, appropriately changing the development paths of electron avalanches and increasing the number of initial electrons can effectively inhibit the formation of filamentary discharge. Based on the aforementioned phenomenon, we propose a method of using microdischarge electrodes to produce a macroscopic discharge phenomenon. In the form of an asymmetric structure composed of a carbon fiber electrode, an electrode structure of carbon fiber spiral-contact type is designed to achieve an atmospheric pressure glow discharge in air, which is characterized by low discharge voltage, low energy consumption, good diffusion and less ozone generation.展开更多
Native calf thymus double stranded DNA (ct-dsDNA) is successfully immobilized from solution onto carbon substrates by covalent linkages under an optimized deposition potential of 1 .8±0.3 V vs. 50 mmol/L NaCl-Ag/...Native calf thymus double stranded DNA (ct-dsDNA) is successfully immobilized from solution onto carbon substrates by covalent linkages under an optimized deposition potential of 1 .8±0.3 V vs. 50 mmol/L NaCl-Ag/AgCl. The long chain DNA fabricates a layer of well conductive nano-netting intertexture, which is stable in pH 14 alkaline solution and in boiling water. The ct-dsDNA modified carbon fiber disk electrode shows two to three orders of magnitude enlarged electrode effective surface area and similarly enlarged voltammetric responses to Co(phen)33+ and dopamine. Thermal dissociated single stranded ct-DNA can also lead to similar result. This modified electrode will find wide applications in the fields of DNA-based electrochemical biosensors.展开更多
Alternating current electroluminescent(ACEL)fibers with wearable characteristics,such as flexibility,light weight,stitch-ability and comfort,are emerging in textile displays for daily applications.To construct efficie...Alternating current electroluminescent(ACEL)fibers with wearable characteristics,such as flexibility,light weight,stitch-ability and comfort,are emerging in textile displays for daily applications.To construct efficient ACEL fibers,a judiciously designed and low-cost electrode is also extremely important but seems to receive less attention.Inspired by fiber dyeing,we propose a method that employs non-noble metals to design fiber electrodes by constructing microconductive channels inside commercial fibers.This method relies on the window period formed by the glass transition temperature of the PAN fibers,which is sufficiently flexible to extend to mass production at a low cost(approximately US$1.86/kg).The resulting ACEL fibers interwoven with a transparent fiber electrode formed a textile display with an acceptable luminescence performance of 46 cd·m^(-2)(160 V).Notably,a visual feedback e-textile(VFET)was constructed by integrating fiber sensors,which dem-onstrates the concept of wearable real-time visual monitoring and interaction.Compared with their individual counterparts,VFET has been conveniently and efficiently for visual monitoring,communication,and interaction,i.e.,the visualization of physiological parameters(heartbeat,respiration,etc.)and nonverbal communications(literal or cryptographic)for special groups and specific scenes.展开更多
To detect gatifloxacin （GAT） residue in swine urine, an electrochemical immunoassay was established, An indirect competitive immunoassay was developed, in which the coating antigen is immobilized in an enzyme-linked...To detect gatifloxacin （GAT） residue in swine urine, an electrochemical immunoassay was established, An indirect competitive immunoassay was developed, in which the coating antigen is immobilized in an enzyme-linked immunosorbent assay （ELISA） plate and GAT residue from the sample competes with the limited binding sites in added anti-GAT antibody. Horseradish peroxidase （HRP） conjugated to goat anti-rabbit IgG was used as the enzymatic label. A carbon fiber working electrode was constructed and current signals were detected by using hydrogen peroxide as a substrate and hydroquinone as an electrochemical mediator. The electrochemical immunoassay was evaluated by analysis of GAT in buffer or swine urine and an average value of half inhibition concentration （IC50） of 8.9 ng/ml was obtained. Excellent specificity of the antibody was achieved with little cross-reaction with Iomefloxacin （3.0%）, ciprofloxacin （3.0%）, and ofloxacin （1.9%） among commonly used （fluoro）quinolones. In conclusion, the im- munoassay system developed in this research can be used as a rapid, powerful and on-site analytical tool to detect GAT residue in foods and food products.展开更多
A carbon fiber paste electrode using ionic liquid as the binder （CFILE） was fabricated. The electrochemical characteristics of the electrode was examined in ferro-/ferricyanide solution and showed better conductivit...A carbon fiber paste electrode using ionic liquid as the binder （CFILE） was fabricated. The electrochemical characteristics of the electrode was examined in ferro-/ferricyanide solution and showed better conductivity and reversibility when compared with graphite paste-ionic liquid electrode （GPILE） and a little better than that on the carbon nanotube paste-ionic liquid electrode （CNTILE）. Glyphosate （GLY）, a pesticide, exhibited excellent catalysis to the oxidation of Ru（bpy）3^2＋ on CFILE and brought an obvious enhancement to the electrochemiluminescence （ECL） intensity of Ru（bpy）3^2＋ . Based on the catalytic ability of GLY, a simple ECL method for GLY detection had been established. Under optimum conditions, the enhanced ECL intensities were found to had linearly respond to the GLY concentration between 3.0× 10 ^-7 and 3.0× 10 ^- 5mol/L, and the detection limit （S/N=3） was 2.0× 10 ^-7 mol/L. The electrode also showed excellent sensitivity in detecting GLY-spiked soybean samples. The linear range for GLY in soybean samples was 1.0× 10 ^-6-4.0× 10 ^-5 mol/L and the detection limit was 5.0× 10 ^-7 mol/L, equal to 8.45 μg GLY in per gram of soybean. The detection limit in soybean sample was lower than the USA, EU regulation and so on. If the method is coupled with the separation technology, it can be applied to detect the GLY in the contaminated samples.展开更多
Fiber-shaped photocapacitors(FPCs)based on shared bifunctional fiber electrodes for supercapacitors and solar cells hold great potential for the realization of self-powered systems for flexible wearable electronics.Ho...Fiber-shaped photocapacitors(FPCs)based on shared bifunctional fiber electrodes for supercapacitors and solar cells hold great potential for the realization of self-powered systems for flexible wearable electronics.However,the reported electrodes for FPCs still face certain limitations,such as limited specific energy density,low total photochemical–electric energy conver-sion efficiency(ηtotal),and poor flexibility.Herein,hollow fibers consisting of partially reduced graphene oxide and a highly conductive polymer are assembled by wet-spinning and employed as shared bifunctional fibers to fabricate self-powered FPCs.Intriguingly,the FPCs achieve high flexibility and aηtotal of 4.2%.This study illustrates a feasible way to design high-performance FPCs and their applications in flexible electronics.展开更多
基金The authors gratefully acknowledge financial support from the Natural Science Foundation of Anhui Provincethe Natural Science Foundation of Anhui Education Committee(2001kj185).
文摘The electrochemical behaviors (cyclic voltammetry, CV and different pulse voltammetry, DPV) of dopamine (DA) were studied in this paper. The result indicated that the oxidation of dopamine was controlled by diffusion and adsorption simultaneously at nano-gold (NG) modified carbon fiber electrode (CFE). This modified electrode can separate the peak potentials of dopamine and ascorbic acid (AA). The peak current of DA in DPV curve was found to be linearly proportional to the concentration of DA at range of 2.0?0-6～1.5?0-5mol/L and 1.0?0-5～5.0?0-4mol/L, respectively.
基金supported by fund of the National Natural Science Foundation of China(No.12172024).
文摘Structural energy storage composites present advantages in simultaneously achieving structural strength and electrochemical properties.Adoption of carbon fiber electrodes and resin structural electrolytes in energy storage composite poses challenges in maintaining good mechanical and electrochemical properties at reasonable cost and effort.Here,we report a simple method to fabricate structural supercapacitor using carbon fiber electrodes(modified by Ni-layered double hydroxide(Ni-LDH)and in-situ growth of Co-metal-organic framework(Co-MOF)in a two-step process denoted as Co-MOF/Ni-LDH@CF)and bicontinuous-phase epoxy resin-based structural electrolyte.Co-MOF/Ni-LDH@CF as electrode material exhibits improved specific capacity(42.45 F·g^(-1))and cycle performance(93.3%capacity retention after 1000 cycles)in a three-electrode system.The bicontinuous-phase epoxy resin-based structural electrolyte exhibits an ionic conductivity of 3.27×10^(-4) S·cm^(-1).The fabricated Co-MOF/Ni-LDH@CF/SPE-50 structural supercapacitor has an energy density of 3.21 Wh·kg^(-1) at a power density of 42.25 W·kg^(-1),whilst maintaining tensile strength and modulus of 334.6 MPa and 25.2 GPa.These results show practical potential of employing modified commercial carbon fiber electrodes and epoxy resin-based structural electrolytes in structural energy storage applications.
基金supported by the National Defense Science and Technology Innovation Zone Project(No.18-H863-05-ZT-001-018-09)
文摘A novel sensor for ocean electric field testing has been fabricated by polyacrylonitrile-based on carbon fibers with electro-chemical oxidation.The surface profile characteristics of the carbon fibers were characterized by scanning electron microscope,Fourier transform infrared spectra and contact angle.Cyclic voltammetry and Tafel curves have been used to study its electro-chemical performances.Two identical electrodes in sea water as the electric field sensor will swiftly respond to applied electric field which causes positive and negative ions to move in opposite direction,resulting in a electric potential difference(ΔE).Test result indicates that the offset potential is typically below 1 m V with a drift of 60-170μVd^-1.Typical self noise level is 1.07 nV√Hz^(1/2)@1 Hz.The electric field response indicates that the modified electrode pair shows better response to AC sine signal of amplitude and frequency(5 mV and 1 mHz)respectively than its blank.The electric field response model of the modified electrodes is creatively presented according to its electric double layer capacitance and Faraday pseudo-capacitance.Many advantages of the carbon fiber electric field electrode will make it have potential application prospect.
基金funded by a NASA Grant NNX13AF46Apartly by the National Institute for Occupational Safety and Health through the UC Pilot Research Project Training Program ERC Grant #T42OH008432
文摘Dry-spun Carbon Nanotube(CNT)fibers were surface-modified by atmospheric pressure oxygen plasma functionalization using a well controlled and continuous process.The fibers were characterized by scanning electron microscopy(SEM),Raman spectroscopy,and X-ray Photoelectron Spectroscopy(XPS).It was found from the conducted electrochemical measurements that the functionalized fibers showed a 132.8% increase in specific capacitance compared to non-functionalized fibers.Dye-adsorption test and the obtained Randles-Sevcik plot demonstrated that the oxygen plasma functionalized fibers exhibited increased surface area.It was further established by Brunauer-Emmett-Teller(BET)measurements that the surface area of the CNT fibers was increased from 168.22 m^2/g to 208.01 m^2/g after plasma functionalization.The pore size distribution of the fibers was also altered by this processing.The improved electrochemical data was attributed to enhanced wettability,increased surface area,and the presence of oxygen functional groups,which promoted the capacitance of the fibers.Fiber supercapacitors were fabricated from the oxygen plasma functionalized CNT fiber electrodes using different electrolyte systems.The devices with functionalized electrodes exhibited excellent cyclic stability(93.2% after 4000 cycles),flexibility,bendability,and good energy densities.At 0.5 m A/cm^2,the EMIMBF4 device revealed a specific capacitance,which is 27% and 65%greater than the specific capacitances of devices using EMIMTFSI and H2SO4 electrolytes,respectively.The practiced in this work plasma surface processing can be employed in other applications where fibers,yarns,ribbons,and sheets need to be chemically modified.
基金Supported by the National Natural Science Foundation of China under Grant No 51577011
文摘During discharge, appropriately changing the development paths of electron avalanches and increasing the number of initial electrons can effectively inhibit the formation of filamentary discharge. Based on the aforementioned phenomenon, we propose a method of using microdischarge electrodes to produce a macroscopic discharge phenomenon. In the form of an asymmetric structure composed of a carbon fiber electrode, an electrode structure of carbon fiber spiral-contact type is designed to achieve an atmospheric pressure glow discharge in air, which is characterized by low discharge voltage, low energy consumption, good diffusion and less ozone generation.
文摘Native calf thymus double stranded DNA (ct-dsDNA) is successfully immobilized from solution onto carbon substrates by covalent linkages under an optimized deposition potential of 1 .8±0.3 V vs. 50 mmol/L NaCl-Ag/AgCl. The long chain DNA fabricates a layer of well conductive nano-netting intertexture, which is stable in pH 14 alkaline solution and in boiling water. The ct-dsDNA modified carbon fiber disk electrode shows two to three orders of magnitude enlarged electrode effective surface area and similarly enlarged voltammetric responses to Co(phen)33+ and dopamine. Thermal dissociated single stranded ct-DNA can also lead to similar result. This modified electrode will find wide applications in the fields of DNA-based electrochemical biosensors.
基金financially by the National Natural Science Foundation of China(52103056)the Shandong Province Postdoctoral Innovation Project(SDCXZG202302021)+2 种基金the Opening Project of Sichuan Provincial Engineering Research Center of Functional Development and Application of High-Performance Special Textile Materials(Chengdu Textile College,2024FDAST-B04)the Research and Development Program of Shandong Province of China(grant numbers 2019GGXI02022,2019JZZY010340 and 2019JZZY010335)the Shenzhen Science and Technology Program(KQTD 20221101093605019).
文摘Alternating current electroluminescent(ACEL)fibers with wearable characteristics,such as flexibility,light weight,stitch-ability and comfort,are emerging in textile displays for daily applications.To construct efficient ACEL fibers,a judiciously designed and low-cost electrode is also extremely important but seems to receive less attention.Inspired by fiber dyeing,we propose a method that employs non-noble metals to design fiber electrodes by constructing microconductive channels inside commercial fibers.This method relies on the window period formed by the glass transition temperature of the PAN fibers,which is sufficiently flexible to extend to mass production at a low cost(approximately US$1.86/kg).The resulting ACEL fibers interwoven with a transparent fiber electrode formed a textile display with an acceptable luminescence performance of 46 cd·m^(-2)(160 V).Notably,a visual feedback e-textile(VFET)was constructed by integrating fiber sensors,which dem-onstrates the concept of wearable real-time visual monitoring and interaction.Compared with their individual counterparts,VFET has been conveniently and efficiently for visual monitoring,communication,and interaction,i.e.,the visualization of physiological parameters(heartbeat,respiration,etc.)and nonverbal communications(literal or cryptographic)for special groups and specific scenes.
基金supported by the National High-Tech R&D Program(863)of China(Nos.07AA10Z435 and 2007AA06A407)the National Natural Science Foundation of China(No.20675048)+1 种基金the Fundamental Research Funds for the Central Universities(No.65011121)the Shandong Provincial Natural Science Foundation(No.Y2008B31),China
文摘To detect gatifloxacin （GAT） residue in swine urine, an electrochemical immunoassay was established, An indirect competitive immunoassay was developed, in which the coating antigen is immobilized in an enzyme-linked immunosorbent assay （ELISA） plate and GAT residue from the sample competes with the limited binding sites in added anti-GAT antibody. Horseradish peroxidase （HRP） conjugated to goat anti-rabbit IgG was used as the enzymatic label. A carbon fiber working electrode was constructed and current signals were detected by using hydrogen peroxide as a substrate and hydroquinone as an electrochemical mediator. The electrochemical immunoassay was evaluated by analysis of GAT in buffer or swine urine and an average value of half inhibition concentration （IC50） of 8.9 ng/ml was obtained. Excellent specificity of the antibody was achieved with little cross-reaction with Iomefloxacin （3.0%）, ciprofloxacin （3.0%）, and ofloxacin （1.9%） among commonly used （fluoro）quinolones. In conclusion, the im- munoassay system developed in this research can be used as a rapid, powerful and on-site analytical tool to detect GAT residue in foods and food products.
基金Project supported by the National Natural Science Foundation of China （No. 20905013）, the Special Foundation for Young Scientists of Fujian Prov- ince, China （No. 2008F3057 ） and the Science and Technology Project of Putian [No. 2009 S 02 （2）].
文摘A carbon fiber paste electrode using ionic liquid as the binder （CFILE） was fabricated. The electrochemical characteristics of the electrode was examined in ferro-/ferricyanide solution and showed better conductivity and reversibility when compared with graphite paste-ionic liquid electrode （GPILE） and a little better than that on the carbon nanotube paste-ionic liquid electrode （CNTILE）. Glyphosate （GLY）, a pesticide, exhibited excellent catalysis to the oxidation of Ru（bpy）3^2＋ on CFILE and brought an obvious enhancement to the electrochemiluminescence （ECL） intensity of Ru（bpy）3^2＋ . Based on the catalytic ability of GLY, a simple ECL method for GLY detection had been established. Under optimum conditions, the enhanced ECL intensities were found to had linearly respond to the GLY concentration between 3.0× 10 ^-7 and 3.0× 10 ^- 5mol/L, and the detection limit （S/N=3） was 2.0× 10 ^-7 mol/L. The electrode also showed excellent sensitivity in detecting GLY-spiked soybean samples. The linear range for GLY in soybean samples was 1.0× 10 ^-6-4.0× 10 ^-5 mol/L and the detection limit was 5.0× 10 ^-7 mol/L, equal to 8.45 μg GLY in per gram of soybean. The detection limit in soybean sample was lower than the USA, EU regulation and so on. If the method is coupled with the separation technology, it can be applied to detect the GLY in the contaminated samples.
基金supports from National Natural Science Foundation of China(No.21875226,52072352,U20A2072)Foundation for the Youth S&T Innovation Team of Sichuan Province(2020JDTD0035).
文摘Fiber-shaped photocapacitors(FPCs)based on shared bifunctional fiber electrodes for supercapacitors and solar cells hold great potential for the realization of self-powered systems for flexible wearable electronics.However,the reported electrodes for FPCs still face certain limitations,such as limited specific energy density,low total photochemical–electric energy conver-sion efficiency(ηtotal),and poor flexibility.Herein,hollow fibers consisting of partially reduced graphene oxide and a highly conductive polymer are assembled by wet-spinning and employed as shared bifunctional fibers to fabricate self-powered FPCs.Intriguingly,the FPCs achieve high flexibility and aηtotal of 4.2%.This study illustrates a feasible way to design high-performance FPCs and their applications in flexible electronics.
