The effect of transition metal ions(M^(2+)=Mn^(2+),Ni^(2+),Co^(2+),Cu^(2+)) on the chemical synthesis of polyaniline(PANI) used as a platinum-free counter electrode(CE) in dye-sensitized solar cells(DSSCs) was investi...The effect of transition metal ions(M^(2+)=Mn^(2+),Ni^(2+),Co^(2+),Cu^(2+)) on the chemical synthesis of polyaniline(PANI) used as a platinum-free counter electrode(CE) in dye-sensitized solar cells(DSSCs) was investigated.PANI was synthesized by co-polymerization of aniline in the presence of different transition metal ions by using potassium dichromate in acidic medium. It was found that the ion doping of PANI showed a certain catalytic activity for the regeneration of traditional iodide/triiodide(I^-/I_3^-) redox couples. The power conversion efficiency(η) of PANI CEs doped with Mn^(2+),Ni^(2+),Co^(2+) (4.41%, 2.36% and 2.10%, respectively) were higher than 1.94%, the value measured for PANI CE without doping. Doping with Cu^(2+)decreased the power conversion efficiency of PANI CE(PANI-Cu^(2+) η = 1.41%). The electrical properties of the PANI, PANI-Ni^(2+), PANI-Co^(2+),PANI-Mn^(2+) and PANI-Cu^(2+) were studied by cyclic voltammetry(CV), impedance(EIS), and Tafel polarization curve. The experimental results confirmed that PANI was affected by the doping of different transition metal ions(M^(2+)=Mn^(2+),Ni^(2+),Co^(2+),Cu^(2+)). These results indicate a potential application of ion doped PANI as counter electrode in cost-effective DSSCs.展开更多
Platinum(Pt)/nanofibrous polyaniline(PANI) electrode was prepared by pulse galvanostatic method and characterized by scanning electron microscopy.The electrochemical behavior of L-cysteine at the Pt/nanofibrous PANI e...Platinum(Pt)/nanofibrous polyaniline(PANI) electrode was prepared by pulse galvanostatic method and characterized by scanning electron microscopy.The electrochemical behavior of L-cysteine at the Pt/nanofibrous PANI electrode was investigated by cyclic voltammetry.The results indicate that the pH value of the solution and the Pt loading of the electrode have great effect on the electrocatalytic property of the Pt /nanofibrous PANI electrode;the suitable Pt loading of the electrode is 600 μg/cm2 and the suitable pH value of the solution is 4.5 for investigating L-cysteine oxidation.The L-cysteine sensor based on the Pt/nanofibrous PANI electrode has a good selectivity,reproducibility and stability.The Pt/nanofibrous PANI electrode is highly sensitive to L-cysteine,and the linear calibration curve for the oxidation of L-cysteine can be observed in the range of 0.2-5.0 mmol/L.展开更多
Electrochemical Betted not only can obtain the conducting film of polyaniline on a glass carbon electrode, but also can imobilize PMo_(12)O_(40)^(3-) in the film to form a organic conducting film electrode modified by...Electrochemical Betted not only can obtain the conducting film of polyaniline on a glass carbon electrode, but also can imobilize PMo_(12)O_(40)^(3-) in the film to form a organic conducting film electrode modified by heteropolyanion.The paper here reports electrochemical changes in the preparation of PMo_(12)O_(40)^(3-)-polyaniline modified electrode, the electrochemical reaction mechanism of the modified electrode was obtained from the study on its redox properties.Moreover, the above electrode showed marked electrocatalysis for the reduction reaction of CIO_(?)^-.展开更多
A simple route to synthesize the polyaniline(PANI) nanofibers with diameter about 150 nm was reported. In this strategy, the PANI nanofibers were fabricated by electrochemical deposition by using two-electrode configu...A simple route to synthesize the polyaniline(PANI) nanofibers with diameter about 150 nm was reported. In this strategy, the PANI nanofibers were fabricated by electrochemical deposition by using two-electrode configuration in 0.01 M aniline and 0.01 M H_2SO_4 electrolytes. The as-prepared materials were characterized by scanning electron microscopy(SEM), infrared spectroscopy(FTIR), Raman spectroscopy and thermogravimetric analysis(TGA). The electrochemical properties of the PANI nanofibers electrode as supercapacitor materials were investigated. The PANI nanofibers electrode showed high capacitance of 485 F·g^(-1)at 0.1 A·g^(-1), and the decrease in the specific capacitance is about 3.5% in 1 000 cycles. The results indicate that the PANI nanofibers electrode shows high stability and retains its electrochemical capacitance property over 1 000 cycles, suggesting PANI nanofibers have promising applications in high-performance supercapacitors.展开更多
The oxidation of methanol was investigated on platinum-modified polyaniline electrode. Changes in the electrode rotation rates (Ω) during platinum electrodeposition remarkably affect the formation and distribution o...The oxidation of methanol was investigated on platinum-modified polyaniline electrode. Changes in the electrode rotation rates (Ω) during platinum electrodeposition remarkably affect the formation and distribution of platinum in the polymer matrix and consequently lead to different currents of methanol oxidation. The results show that platinum loading is proportional to rotation ratesΩ1/2.展开更多
Nanostructured porous polyaniline(PANI)has been synthesized and coated simultaneously on a highly flexible and conductive carbon cloth(CC)substrate using a simple in-situ chemical oxidative polymerization technique.PA...Nanostructured porous polyaniline(PANI)has been synthesized and coated simultaneously on a highly flexible and conductive carbon cloth(CC)substrate using a simple in-situ chemical oxidative polymerization technique.PANI coated CC(PANI-CC)based flexible electrodes were further used for the fabrication of flexible supercapacitor devices.For the comparison purpose,pure PANI has also been synthesized and tested for its electrochemical performance.The energy storage capacity of PANI and PANI–CC composite was investigated using electrochemical techniques like CV,GCD,and EIS in a potential range from 0 to 0.8 V in 1 M H_(2)SO_(4)electrolyte.PANI-CC flexible electrodes exhibited the highest specific capacitance of 691 F/g;whereas,pure PANI could only achieve 575 F/g of specific capacitance at 1 A/g.Composite also exhibited outstanding cyclic stability by recollecting 94%of its initial capacitance after 2000 GCD cycles.For actual implementation,a flexible supercapacitor device has been fabricated using stainless steel sheets and PANI-CC flexile electrodes.The energy storage performance of the PANI-CC flexible supercapacitor device was tested at several bending angles,which resulted in 72%of capacitance retention at a maximum bending angle of 140°compared to the capacitance obtained at an angle 0°(flat state).PANI-CC exhibited improved electrochemical performance than pure PANI due to the synergistic effect between PANI and CC.Here,CC helped in enhancing the conductivity and stability;whereas,PANI boosted the capacitance owing to its excellent porosity and fast pseudocapacitive charge storage response.展开更多
Taking the nano-sized carbon black and aniline monomer as precursor and （NH4）2S2O6 as oxidant, the well coated C/polyaniline（C/PANI） composite materials were prepared by in situ polymerization of the aniline on th...Taking the nano-sized carbon black and aniline monomer as precursor and （NH4）2S2O6 as oxidant, the well coated C/polyaniline（C/PANI） composite materials were prepared by in situ polymerization of the aniline on the surface of well-dispersed nano-sized carbon black for supercapacitor. The micro-structure of the C/PANI composite electrode materials were analyzed by SEM. The electrochemical properties of C/ PANI and PANI composite electrode were characterized by means of the galvanostatic charge-discharge experiment, cyclic voltammetric measurement and impedance spectroscopy analysis. The results show that by adding the nano-sized carbon black in the process of chemical polymerization of the aniline, the polyaniline can be in situ polymerized and well-coated onto the carbon black particles, which may effectively improve the aggregation of particles and the electrolyte penetration. What’s more , the maximum of specific capacitance of C/PANI electrode 437.6F·g -1 can be attained. Compared with PANI electrode, C/PANI electrode shows more desired capacitance characteristics, smaller internal resistance and better cycle performance.展开更多
The photo-corrosion of electrodeposited polycrystalline CdSe electrode was inhibited effectively by coating a thin layer of the conductive polyaniline （PAN） film. The relation between the performance and internal ba...The photo-corrosion of electrodeposited polycrystalline CdSe electrode was inhibited effectively by coating a thin layer of the conductive polyaniline （PAN） film. The relation between the performance and internal band structure of such film-covered PAN/CdSe electrode was studied by the electrochemical modulation reflectance spectrum （EMRS）. EMRS of both CdSe and PAN/CdSe electrodes in K4Fe（CN）6/K3Fe（CN）6 solution exhibited typical France-Keidysh oscillations, by which the values of the energy gap and flat band potential were determined. The EMRS results indicated that the energy band structure of CdSe electrode was not changed after coated with PAN film, so that the photoelectrochemical characteristic of PAN/CdSe electrode was rather similar to that of CdSe electrode.展开更多
Metallic lithium is regarded as one of the most promising electrode materials to break through the energy density bottleneck of current commercial lithium-ion batteries.However,the practical implementation of lithium ...Metallic lithium is regarded as one of the most promising electrode materials to break through the energy density bottleneck of current commercial lithium-ion batteries.However,the practical implementation of lithium metal anode is limited by the unstable electrode interface significantly,which directly induces a low Coulombic efficiency,short cycling lifespan,and dendritic lithium growth behavior.In this study,via in situ electropolymerization,lithiophilic and conformal polyaniline layer is developed to improve the initial lithium nucleation and plating process,reducing the interface charge transfer resistance and promoting uniform lithium plating/stripping behavior.Meanwhile,the polyaniline layer exhibits good adhesion to the substrate.As a result,the Li/Cu half cell delivers a high Coulombic efficiency of 99.1%for 400 cycles at 1.0 mA·cm^(−2)with polyaniline layer.In addition,long-term stable cycling at a current density of 1.0 mA·cm^(−2)for 1300 h has been achieved for lithium metal anode.This strategy provides a new perspective for the practical lithium metal batteries.展开更多
A reflux-treatment of soluble polyaniline(SPA)in dimethylformamide(DMF)containing CoCl_2 yields an active catalyst for dioxygen reduction which can be adsorbed on the electrode surface firmly.The catalytic reduction o...A reflux-treatment of soluble polyaniline(SPA)in dimethylformamide(DMF)containing CoCl_2 yields an active catalyst for dioxygen reduction which can be adsorbed on the electrode surface firmly.The catalytic reduction of dioxygen at the glassy carbon(GC)electrode modified by the cata- lyst was studied with cyclic voltammetry(CV),rotating disk electrode(RDE)and rotating ring-disk electrode(RRDE).The kinetic process of dioxygen reduction at the modified electrode was analyzed with a new RRDE theory dealing with a nondiffusion-controlled process on ring electrode.The rate constants for each scheme of dioxygen reduction were calculated,showing that only 2-electron reduction to H_2O_2 was conducted at the modified electrode.The effect of solution acidity on the electrocatalytic behaviour for dioxygen reduction was investigated.A possibility of initiating catalytic activity for dioxygen reduction was explored with ESCA method.展开更多
基金Supported by the National Natural Science Foundation of China(21473048,21303039)the Natural Science Foundation of Hebei Province(B2016205161,B2015205163)the 2015 Hebei Province Undergraduate Training Programs for Innovation and Entrepreneurship
文摘The effect of transition metal ions(M^(2+)=Mn^(2+),Ni^(2+),Co^(2+),Cu^(2+)) on the chemical synthesis of polyaniline(PANI) used as a platinum-free counter electrode(CE) in dye-sensitized solar cells(DSSCs) was investigated.PANI was synthesized by co-polymerization of aniline in the presence of different transition metal ions by using potassium dichromate in acidic medium. It was found that the ion doping of PANI showed a certain catalytic activity for the regeneration of traditional iodide/triiodide(I^-/I_3^-) redox couples. The power conversion efficiency(η) of PANI CEs doped with Mn^(2+),Ni^(2+),Co^(2+) (4.41%, 2.36% and 2.10%, respectively) were higher than 1.94%, the value measured for PANI CE without doping. Doping with Cu^(2+)decreased the power conversion efficiency of PANI CE(PANI-Cu^(2+) η = 1.41%). The electrical properties of the PANI, PANI-Ni^(2+), PANI-Co^(2+),PANI-Mn^(2+) and PANI-Cu^(2+) were studied by cyclic voltammetry(CV), impedance(EIS), and Tafel polarization curve. The experimental results confirmed that PANI was affected by the doping of different transition metal ions(M^(2+)=Mn^(2+),Ni^(2+),Co^(2+),Cu^(2+)). These results indicate a potential application of ion doped PANI as counter electrode in cost-effective DSSCs.
基金Project(20050532008) supported by the PhD. Program Foundation of Ministry of Education of ChinaProject(06JJ4005) supported by the Natural Science Foundation of Hunan Province+1 种基金 Project(20060400874)supported by the Postdoctoral Foundation of China Project supported by the Postdoctoral Foundation of Hunan University
文摘Platinum(Pt)/nanofibrous polyaniline(PANI) electrode was prepared by pulse galvanostatic method and characterized by scanning electron microscopy.The electrochemical behavior of L-cysteine at the Pt/nanofibrous PANI electrode was investigated by cyclic voltammetry.The results indicate that the pH value of the solution and the Pt loading of the electrode have great effect on the electrocatalytic property of the Pt /nanofibrous PANI electrode;the suitable Pt loading of the electrode is 600 μg/cm2 and the suitable pH value of the solution is 4.5 for investigating L-cysteine oxidation.The L-cysteine sensor based on the Pt/nanofibrous PANI electrode has a good selectivity,reproducibility and stability.The Pt/nanofibrous PANI electrode is highly sensitive to L-cysteine,and the linear calibration curve for the oxidation of L-cysteine can be observed in the range of 0.2-5.0 mmol/L.
文摘Electrochemical Betted not only can obtain the conducting film of polyaniline on a glass carbon electrode, but also can imobilize PMo_(12)O_(40)^(3-) in the film to form a organic conducting film electrode modified by heteropolyanion.The paper here reports electrochemical changes in the preparation of PMo_(12)O_(40)^(3-)-polyaniline modified electrode, the electrochemical reaction mechanism of the modified electrode was obtained from the study on its redox properties.Moreover, the above electrode showed marked electrocatalysis for the reduction reaction of CIO_(?)^-.
基金Funded by the National Natural Science Foundation of China(No.21706092)the Hubei Province Natural Science Foundation of China(No.2018CFB520)
文摘A simple route to synthesize the polyaniline(PANI) nanofibers with diameter about 150 nm was reported. In this strategy, the PANI nanofibers were fabricated by electrochemical deposition by using two-electrode configuration in 0.01 M aniline and 0.01 M H_2SO_4 electrolytes. The as-prepared materials were characterized by scanning electron microscopy(SEM), infrared spectroscopy(FTIR), Raman spectroscopy and thermogravimetric analysis(TGA). The electrochemical properties of the PANI nanofibers electrode as supercapacitor materials were investigated. The PANI nanofibers electrode showed high capacitance of 485 F·g^(-1)at 0.1 A·g^(-1), and the decrease in the specific capacitance is about 3.5% in 1 000 cycles. The results indicate that the PANI nanofibers electrode shows high stability and retains its electrochemical capacitance property over 1 000 cycles, suggesting PANI nanofibers have promising applications in high-performance supercapacitors.
文摘The oxidation of methanol was investigated on platinum-modified polyaniline electrode. Changes in the electrode rotation rates (Ω) during platinum electrodeposition remarkably affect the formation and distribution of platinum in the polymer matrix and consequently lead to different currents of methanol oxidation. The results show that platinum loading is proportional to rotation ratesΩ1/2.
基金the research grant obtained from the Government of India,Under the DST-Nanomission program(No.SR/NM/NS-1110/2012)the DST-Inspire program(IFA12-PH-33)。
文摘Nanostructured porous polyaniline(PANI)has been synthesized and coated simultaneously on a highly flexible and conductive carbon cloth(CC)substrate using a simple in-situ chemical oxidative polymerization technique.PANI coated CC(PANI-CC)based flexible electrodes were further used for the fabrication of flexible supercapacitor devices.For the comparison purpose,pure PANI has also been synthesized and tested for its electrochemical performance.The energy storage capacity of PANI and PANI–CC composite was investigated using electrochemical techniques like CV,GCD,and EIS in a potential range from 0 to 0.8 V in 1 M H_(2)SO_(4)electrolyte.PANI-CC flexible electrodes exhibited the highest specific capacitance of 691 F/g;whereas,pure PANI could only achieve 575 F/g of specific capacitance at 1 A/g.Composite also exhibited outstanding cyclic stability by recollecting 94%of its initial capacitance after 2000 GCD cycles.For actual implementation,a flexible supercapacitor device has been fabricated using stainless steel sheets and PANI-CC flexile electrodes.The energy storage performance of the PANI-CC flexible supercapacitor device was tested at several bending angles,which resulted in 72%of capacitance retention at a maximum bending angle of 140°compared to the capacitance obtained at an angle 0°(flat state).PANI-CC exhibited improved electrochemical performance than pure PANI due to the synergistic effect between PANI and CC.Here,CC helped in enhancing the conductivity and stability;whereas,PANI boosted the capacitance owing to its excellent porosity and fast pseudocapacitive charge storage response.
基金Project(2005CB623703) supported by the National Basic Research Program of China project(5JJ30103) supported bythe Natural Science Foundation of Hunan Province
文摘Taking the nano-sized carbon black and aniline monomer as precursor and （NH4）2S2O6 as oxidant, the well coated C/polyaniline（C/PANI） composite materials were prepared by in situ polymerization of the aniline on the surface of well-dispersed nano-sized carbon black for supercapacitor. The micro-structure of the C/PANI composite electrode materials were analyzed by SEM. The electrochemical properties of C/ PANI and PANI composite electrode were characterized by means of the galvanostatic charge-discharge experiment, cyclic voltammetric measurement and impedance spectroscopy analysis. The results show that by adding the nano-sized carbon black in the process of chemical polymerization of the aniline, the polyaniline can be in situ polymerized and well-coated onto the carbon black particles, which may effectively improve the aggregation of particles and the electrolyte penetration. What’s more , the maximum of specific capacitance of C/PANI electrode 437.6F·g -1 can be attained. Compared with PANI electrode, C/PANI electrode shows more desired capacitance characteristics, smaller internal resistance and better cycle performance.
文摘The photo-corrosion of electrodeposited polycrystalline CdSe electrode was inhibited effectively by coating a thin layer of the conductive polyaniline （PAN） film. The relation between the performance and internal band structure of such film-covered PAN/CdSe electrode was studied by the electrochemical modulation reflectance spectrum （EMRS）. EMRS of both CdSe and PAN/CdSe electrodes in K4Fe（CN）6/K3Fe（CN）6 solution exhibited typical France-Keidysh oscillations, by which the values of the energy gap and flat band potential were determined. The EMRS results indicated that the energy band structure of CdSe electrode was not changed after coated with PAN film, so that the photoelectrochemical characteristic of PAN/CdSe electrode was rather similar to that of CdSe electrode.
基金the financial support from the National Key Research and Development Program of China(No.2021YFB2400400)the National Natural Science Foundation of China(No.52073143,Key Project(No.52131306)+4 种基金Distinguished Youth Scientists Project(No.51425301))the State Key Lab Research Foundation(Nos.ZK201805 and ZK201717)the Project on Carbon Emission Peak and Neutrality of Jiangsu Province(No.BE2022031-4)the Natural Science Foundation of Jiangsu Province(Nos.BK20200696,BK20200768,and 20KJB430019)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX20_1072).
文摘Metallic lithium is regarded as one of the most promising electrode materials to break through the energy density bottleneck of current commercial lithium-ion batteries.However,the practical implementation of lithium metal anode is limited by the unstable electrode interface significantly,which directly induces a low Coulombic efficiency,short cycling lifespan,and dendritic lithium growth behavior.In this study,via in situ electropolymerization,lithiophilic and conformal polyaniline layer is developed to improve the initial lithium nucleation and plating process,reducing the interface charge transfer resistance and promoting uniform lithium plating/stripping behavior.Meanwhile,the polyaniline layer exhibits good adhesion to the substrate.As a result,the Li/Cu half cell delivers a high Coulombic efficiency of 99.1%for 400 cycles at 1.0 mA·cm^(−2)with polyaniline layer.In addition,long-term stable cycling at a current density of 1.0 mA·cm^(−2)for 1300 h has been achieved for lithium metal anode.This strategy provides a new perspective for the practical lithium metal batteries.
文摘A reflux-treatment of soluble polyaniline(SPA)in dimethylformamide(DMF)containing CoCl_2 yields an active catalyst for dioxygen reduction which can be adsorbed on the electrode surface firmly.The catalytic reduction of dioxygen at the glassy carbon(GC)electrode modified by the cata- lyst was studied with cyclic voltammetry(CV),rotating disk electrode(RDE)and rotating ring-disk electrode(RRDE).The kinetic process of dioxygen reduction at the modified electrode was analyzed with a new RRDE theory dealing with a nondiffusion-controlled process on ring electrode.The rate constants for each scheme of dioxygen reduction were calculated,showing that only 2-electron reduction to H_2O_2 was conducted at the modified electrode.The effect of solution acidity on the electrocatalytic behaviour for dioxygen reduction was investigated.A possibility of initiating catalytic activity for dioxygen reduction was explored with ESCA method.
