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Electrochemical Double-Layer Capacitors Using Phenolic Resin-Based Carbon Fibers, Rong Xue, Jing-Wang Yan, Ying Tian, Bao-Lian Yi
Electrochemical Double-Layer Capacitors Using Phenolic Resin-Based Carbon Fibers, Rong Xue, Jing-Wang Yan, Ying Tian, Bao-Lian Yi
Journal of Electrochemistry
Phenolic resin-based activated carbon fiber(ACF) was prepared by KOH activation.The electrochemical properties of pulverized phenolic resin-based carbon fiber(P-ACF) were examined in 6 mol·L-1 KOH compared with that of the original ACF.P-ACF exhibited a better capacitive behavior and showed a larger specific capacitance(200 F·g-1) as well as a lower capacitance decrease at high current densities.The pore resistance for ion migration(Rp) in P-ACF was lower(2.96 Ω) than that in ACF(4.65 Ω).Pulverization increased the exposure of the cross section,lowered the contact resistance between the carbon fibers and decreased the pore resistance for ion migration.
Prerapation And Supercapacitor Property Of Mesoporous Carbon Nanofibers, Yong-Wen Wang, Ming-Bo Zheng, Jian Cao, Jie-Ming Cao, Guang-Bin Ji, Jie Tao
Prerapation And Supercapacitor Property Of Mesoporous Carbon Nanofibers, Yong-Wen Wang, Ming-Bo Zheng, Jian Cao, Jie-Ming Cao, Guang-Bin Ji, Jie Tao
Journal of Electrochemistry
Two different mesoporous carbon nanofibers with large mesopore or core-shell structure were prepared by using the resol/F127 mixture to fill the AAO template. The morphology and structural parameters of the samples were characterized by SEM,TEM,and N2 adsorption-desorption analysis. The supercapacitive behaviors of the electrodes were tested by cyclic voltammetry and galvanostatic charge-discharge. The results show that the specific capacitances of mesoporous carbon nanofibers increased obviously and the fine supercapacitive performances were achieved at high scan rate or large current density.
Electrochemical Capacitance Of Mno_2 /Pani Composite, Xiao-Cun Xu, Kai-Yu Liu, Zhi-Gang Yin, Zhe Sun, Geng Su
Electrochemical Capacitance Of Mno_2 /Pani Composite, Xiao-Cun Xu, Kai-Yu Liu, Zhi-Gang Yin, Zhe Sun, Geng Su
Journal of Electrochemistry
Nano-MnO2 was prepared by using P123 as a soft template.The MnO2 /polyaniline composite was further prepared by polymerization of aniline with the nano-MnO2 in acidic conditions and was investigated by XRD and IR.The morphology of nano-MnO2 observed by SEM was changed with the introduction of aniline.The electrochemical properties of MnO2 /PANI electrode were investigated using cyclic voltammetry,galvanostatic charge-discharge and electrochemical impedance spectroscopy.The specific capacitance of MnO2 /PANI electrode could reach as high as 190.8 F·g-1,which decayed only 4.7% over 500 cycles.And the coulombic efficiency has been maintained at above 97%.
Synthesis Of Α-Mno_2 Microspheres For The Application In Supercapacitor, Liang Wang, Gui-Chang Liu, Zhi-Cong Shi
Synthesis Of Α-Mno_2 Microspheres For The Application In Supercapacitor, Liang Wang, Gui-Chang Liu, Zhi-Cong Shi
Journal of Electrochemistry
The MnO2 microspheres were prepared through the oxidation of KMnO4 and MnCO3 microspheres precursor.The microstructure and supercapacitor properties of MnO2 were characterized by XRD,SEM and CV.The results show that MnO2 was in a poorly crystalline state with α-crystallographic form,the size of microspheres typically ranged from 0.5 to 2 μm.Loading 5 mg·cm-2 MnO2 microspheres had excellent capacitance behaviors in 2 mol·L-1(NH4)2SO4 solution.The specific capacitance was 135.6 F·g-1 with the scan rate at 2 mV·s-1,and 118.8 F·g-1 with the large scan rate at 100 mV/s.Coulumbic efficiency was still above 87.8% in the 500 cycles,and the specific capacitance of the 500th cycle was …
Mesoporous Carbon For High Power Supercapacitors, Bin Xu, Lu Peng, Guo-Qing Wang, Gao-Ping Cao, Feng Wu, Yu-Sheng Yang
Mesoporous Carbon For High Power Supercapacitors, Bin Xu, Lu Peng, Guo-Qing Wang, Gao-Ping Cao, Feng Wu, Yu-Sheng Yang
Journal of Electrochemistry
Mesoporous carbon for supercapacitors was prepared from sucrose using nano-CaCO3 as template.The microstructure of the carbon was characterized with N2 adsorption and transmission electron microscopy(TEM) observation.The electrochemical performances were evaluated in 6mol·L-1 KOH aqueous electrolyte with galvanostatic charge/discharge,cyclic voltammetry,and ac impedance spectroscopy.The sucrose-based mesoporous carbon had a surface area of 606 m2/g and enriched mesopores in the range of 10～30 nm.The mesoporous carbon presented a specific capacitance of 125 F/g at a current density of 50 mA/g and outstanding excellent rate performance.As the current density increased to 20 000 mA/g,its capacitance remained at 88 F/g,much higher than the commercial capacitive …
Voltage Delay On Li/Socl_2 And Bcx Cells During Discharge, Shu-Tao Liu, Yi-Ping Wu, Hong-Hua Ge, Guo-Ding Zhou
Voltage Delay On Li/Socl_2 And Bcx Cells During Discharge, Shu-Tao Liu, Yi-Ping Wu, Hong-Hua Ge, Guo-Ding Zhou
Journal of Electrochemistry
The impedance change of both lithium and carbon electrodes during the process of discharge was studied by AC impedance spectroscopy.It shows that the impedance of lithium electrode at initial stage was reduced by 80%～90% and kept nearly unchanged after wards;the carbon electrode impedance initially did not change much but quickly increased just before the end of discharge.The improvement of voltage delay might be related with the higher open-circuit voltage of BCX cell.It is suggested that the voltage delay problem may be solved by the application of supercapacitor.
Preparation And Supercapacitive Properties Of Co(Oh)_2/Nay Composite, Chi Ma, Ling-Bin Kong, Yong-Chun Luo, Long Kang
Preparation And Supercapacitive Properties Of Co(Oh)_2/Nay Composite, Chi Ma, Ling-Bin Kong, Yong-Chun Luo, Long Kang
Journal of Electrochemistry
The Co(OH)2/NaY composite was prepared by chemical precipitation method and then tested as an active electrode material for an electrochemical supercapacitor.The results indicated that the composite displayed superior capacitive performance.The maximum specific capacitance of Co(OH)2 was 632.5 F/g.The structure and electrochemical properties of the composite were also discussed.
Molten Salt Treatment Of Mno_2 And Investigation On Supercapacitor Properties, Ye Chen, Zun-Bo Zhang, Wei Zhang, Liang Liu, Zhi-Min Liu
Molten Salt Treatment Of Mno_2 And Investigation On Supercapacitor Properties, Ye Chen, Zun-Bo Zhang, Wei Zhang, Liang Liu, Zhi-Min Liu
Journal of Electrochemistry
The MnO2 prepared by solid phase method is treated by KCl-NaCl-LiCl molten salt system.The XRD patterns indicated that the crystal structures of MnO2 sample have had the α-MnO2 and γ-MnO2 phase,the crystallinity of sample is increased after treated by molten salt.The electrochemical properties were tested by cyclic voltammetry,constant current charge/discharge and AC impedance.The result shows that the supercapacitor performance of the treated material has improved.The specific discharge capacitance of the treated sample are 129.07 F·g-1,increased by 27.88% compared to 100.94 F·g-1 of untreated sample.Long cycle life and high coulombic efficiency were also demonstrated after charge/discharge 100 cycles.The value of RESR …
A Study On Supercapacitor Based On Aligned Carbon Nanotubes, Xiao-Yan Ye, Yan-Zhi Wang, Hai-Yan Song, Zhuo Sun, Pin-Gang He, Yu-Zhi Fang
A Study On Supercapacitor Based On Aligned Carbon Nanotubes, Xiao-Yan Ye, Yan-Zhi Wang, Hai-Yan Song, Zhuo Sun, Pin-Gang He, Yu-Zhi Fang
Journal of Electrochemistry
Large scale vertically aligned carbon nanotubes(ACNTs) with uniform length and diameter were prepared by the pyrolysis of iron(Ⅱ) phthalocyanine at low pressure.The ACNTs were activated by electrolyte-activation,acid-activation or electrochemical activation.The performance of the capacitor based on activated ACNTs was characterized by cyclic voltammograms which was of rectangular shape,impedence spectroscopy in which the phase is above 80° and the result specific capacitance was 16～32 F/g,which suggest that the ACNTs are the promising material for the supercapacitor.
The Syntheses And Electrochemical Performance Of Nano-Mno_2 For Supercapacitor, Jun Ma, Ming-Sen Zheng, Quan-Feng Dong
The Syntheses And Electrochemical Performance Of Nano-Mno_2 For Supercapacitor, Jun Ma, Ming-Sen Zheng, Quan-Feng Dong
Journal of Electrochemistry
Nano-manganese dioxide were prepared by two different methods which are low temperature solid reaction and chemical deposition.The products were characterized by XRD,SEM,BET and constant current charge-discharge tests.The result shows that there is a close relationship between specific capacitance and BET surface areas.Meanwhile the specific capacitance was impacted little by the structure of the nano-manganese dioxides.However,the product performance of high rates,was influenced by structure,the higher rate can be obtained with the more perfect crystal structure.
Prerapation And Supercapacitor Property Of Al Doped Co_3o_4, Xin Ge, Ye Chen, Chun-Xia Zhang, Chang Shu
Prerapation And Supercapacitor Property Of Al Doped Co_3o_4, Xin Ge, Ye Chen, Chun-Xia Zhang, Chang Shu
Journal of Electrochemistry
With KOH as precipitator to prepare Aluminum doped Co3O4,X-ray diffraction indicated that the doping Al did not change the crystal structure of Co3O4.Electrochemical properties of the sample were tested by cyclic voltammetry and constant-current charge/discharge.The results showed that the chemical doping improved the specific capacitance.When the mol ratio of Co(Ⅱ) with Al(Ⅲ)was 1∶0.05,the specific capacitance was up to 518.07 F/g within 0～400 mV potenitial at current density 5 mA/cm2.
Preparation And Supercapacitor Properties Of Yttrium Doped Nio, Dan-Dan Han
Preparation And Supercapacitor Properties Of Yttrium Doped Nio, Dan-Dan Han
Journal of Electrochemistry
Yttrium doped Nano-NiO were synthesized by chemical precipitation method.Characterization and performance of the samples were studied by X-ray diffraction,the results showed that the doping Yttrium did not change the crystal structure of NiO,but the size of crystalline grain was reduced.The electrochemical properties of the electrode materials were measured in the three electrode system.Electrochemical properties of NiO were researched by cyclic voltammetry,constant current charge/discharge and AC impedance methods.It could be seen that the chemical doping improved the specific capacitance and the utilization of active materials.When the weight ratio of NiO with Y_(2)O_(3)was 1∶0.1,the composite material had the best properties.The maximum discharge …
Modification Of Molybdenum Nitride Electrode For Supercapacitor(I)——The Effect Of Ammonium Vanadate On The Properties Of Molybdenum Nitride Electrode, Xue-Liang Li, Dao-Rong Luo, Hua-Lin Wang, Jian-Bo He, Yun-Guei Zhu
Modification Of Molybdenum Nitride Electrode For Supercapacitor(I)——The Effect Of Ammonium Vanadate On The Properties Of Molybdenum Nitride Electrode, Xue-Liang Li, Dao-Rong Luo, Hua-Lin Wang, Jian-Bo He, Yun-Guei Zhu
Journal of Electrochemistry
The effect of vanadium on the properties of the electrode of molybdenum nitride has been studied by using XRD?SEM and cyclic voltammetry.Modified molybdenum nitride was made as follow:films were coated by dipping titanium sheet in the solution containing different composition of molybdenum oxide,ammonium vanadate,ammonia,glycol and oxalic acid,and coated films are reacted with free ammonia.The results show that the specific capacitance of modified electrode was considerably increased and the operation voltage was broadened with the addition of ammonium vanadate in the dipping solution.The mechanism of these effects generated is the formation of new phase VOMoO 4 in the electrode of molybdenum …