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Full-Text Articles in Engineering

Primary Research Of Reversible Proton Exchange Membrane Regenerative Fuel Cells, Zhigang Shao, Baolian Yi, Ming Han Nov 1998

Primary Research Of Reversible Proton Exchange Membrane Regenerative Fuel Cells, Zhigang Shao, Baolian Yi, Ming Han

Journal of Electrochemistry

In this paper, we report the results of our studies on regenerative proton exchange membrane fuel cell(RPEMRFC) catalysts, electrode preparation and their performances. The Pt catalyst for the oxygen electrode was replaced by 60 w%Pt+40 w%IrO 2 which reduces polarization by 0.2 V in a polymer protone exchange membrane fuel cell. The cycle performance of RPEMRFC was found to be manly effected by the stability of the diffiusion layer of bifunctional oxygen electrode.


The Latest World Wide Progress In Solid Oxide Fuel Cell, Jiang Yi Nov 1998

The Latest World Wide Progress In Solid Oxide Fuel Cell, Jiang Yi

Journal of Electrochemistry

Solid oxide fuel cell(SOFC) is a novel, green electricity generation technology, which has been showing rapid development since 1980's. In light of its high efficiency, environmental friendly, fuel adaptability and long term stability, the Research, Development and Demonstration(RD&D) of this hype of full cell have been emphasized in a large number of developed countries. Based on the information communicated at the latest symposium on SOFC held last year in Aachen(Germany) and the knowledge gained through years of research in this field, a comprehensive review on the latest development of the tubular, this planar SOFC as well as on a number …


A Preliminary Study Of The Synthesis Of Tin Based Amorphous Material And Its Behavior On Lithium Intercalation, Li Liu, Hanxi Yang, Jutang Sun, Xingping Ai Nov 1998

A Preliminary Study Of The Synthesis Of Tin Based Amorphous Material And Its Behavior On Lithium Intercalation, Li Liu, Hanxi Yang, Jutang Sun, Xingping Ai

Journal of Electrochemistry

An amorphous lithium inserting anode material based on Tin oxide glass was synthesized by salification in solution and its properties on lithium intercalation was investigated by X ray diffraction(XRD), microelectrode voltammetry and charge discharge measurements. The results have shown that this kind of material has considerable electrochemical reversibility toward lithium intercalation deintercalation. The available discharge capacity of the material reaches 430 mA·h/g with charge_discharge efficiency over 90%, showing a great potential for practical use.


Studies Of Spinal Li 1+X Mn 2-X O 4 Rechargeable Lithium Ion Battery, Xiaomei Wu, Qinghe Yang, Zhongkao Jin, Haoqing Wu, Xiangfu Zong Nov 1998

Studies Of Spinal Li 1+X Mn 2-X O 4 Rechargeable Lithium Ion Battery, Xiaomei Wu, Qinghe Yang, Zhongkao Jin, Haoqing Wu, Xiangfu Zong

Journal of Electrochemistry

The spinel Li intercalation compound Li 1+ x Mn 2- x O 4(0< x <1) was prepared by using techniques of cyclic voltammetry. The electrochemical parameters of Li 1+ x Mn 2- x O 4 electrode vary as either the starting materials or the synthesis temperature changes. It was found that the initial capacity and reversible behaviors of the Li 1+ x Mn 2- x O 4 electrode depends on the amount of the excess Li, represented as x in Li 1+ x Mn 2- x O 4. The reversible of Li intercalation process for Li 1+ x Mn 2- x O 4 electrode was demonstrate by cyclic voltammograms.


Drect Electro_Oxidation Synthesis Of D Arabinose On Spectroscopic Graphite Electrode, Hei Wei, Huang Ying Nov 1998

Drect Electro_Oxidation Synthesis Of D Arabinose On Spectroscopic Graphite Electrode, Hei Wei, Huang Ying

Journal of Electrochemistry

D Arabinose synthesized by direct electro_oxidative decarboxylation of D gluconate on graphite electrode from aqueous solutions. The effects of D gluconate concentration, electrolysis potential, temperature and electrolyte composition on the current efficiency and product yield of electrosynthsis are discussed. The laboratory scale electrosynthesis was achieved with flow through cell.The optimum technology conditions for electrosynthesis were obtained with orthogonal design method.Both galvanostatic and potentionstatic conditions have been exploited, the later was found to be more effective.


Study On Electrosynthesis Of Butyl Butyrate At Conducting Oxide Anode Support On Titanium, Junxiang He, Jincheng Zhou Nov 1998

Study On Electrosynthesis Of Butyl Butyrate At Conducting Oxide Anode Support On Titanium, Junxiang He, Jincheng Zhou

Journal of Electrochemistry

Synthesis of butyl butyrate by direct electroxidation of n butyl alcohol and the electrochemical behaviors of several selected conducting oxide electrodes (Pb/PbO 2、Ti/PbO 2、i/SnO 2 +Sb 2O 3 /PbO 2 and Ti/SnO 2+Sb 2O 3+PdO x/PbO 2) have been investigated. The results demonstrated that the intermediate layers of SnO 2、Sb 2O 3 and PdO x could significantly decrease the interfacial resistance of the electrodes,and that the Ti/SnO 2+Sb 2O 3+PdO x/PbO 2 electrode possessed better electrocatelytic performance than others.


Direct Electrochemical Reaction Of Cytochrome C At The Poly (Ethylene Oxide) Film Modified Gold Electrodes, Xiaogang Qu, Gongquan Sun Aug 1998

Direct Electrochemical Reaction Of Cytochrome C At The Poly (Ethylene Oxide) Film Modified Gold Electrodes, Xiaogang Qu, Gongquan Sun

Journal of Electrochemistry

In this paper, the direct electrochemical reaction of cytochrome c was sudied at the poly (ethylene oxide) film modified gold electrodes. It was found the PEO is a good promoter for the electrochemical reaction of cytochrome c, and the reversibility of reaction of cytochrome c was found to depend on the molecular weight of PEO and the morphology of the PEO films.


Modification Of Carbon Anode Materials Of Lithium Ion Secondary Battery, Yuping Wan Chunrong Wu, Changyin Jiang, Jiangiun Li Aug 1998

Modification Of Carbon Anode Materials Of Lithium Ion Secondary Battery, Yuping Wan Chunrong Wu, Changyin Jiang, Jiangiun Li

Journal of Electrochemistry

In this paper, the latest research work on modification of carbon anode materials of lithium ion secondary battery is reviewed. Modification methods include: incorporation of nonmetal elements such as boron, silicon, nitrogen, phosphorus and sulfur, metal elements such as potassium, aluminum, gallium and transitional metal elements such as vanadium, nickel, cobalt, copper and iron and surface treatment such as oxidation and formation of surface layer. Since these methods can affect the carbon materials' electronics state, crystal structure and surface structure, the electrochemical properties of the carbon materials could probably be improved. Besides, mechanisms for lithium storage in carbonaceous materials are …


External Transducing Measurement Of The Internal Pressure In Sealed Battery By Resistance Strain Gauge, Hanxi Yang, Ronghui Hu, Xinping Ai, Congzhi Yang, Shengxian Li Aug 1998

External Transducing Measurement Of The Internal Pressure In Sealed Battery By Resistance Strain Gauge, Hanxi Yang, Ronghui Hu, Xinping Ai, Congzhi Yang, Shengxian Li

Journal of Electrochemistry

A novel method to monitor dynamically the internal pressure of sealed battery with no damage of the battery by using of resistance strain measurement technique is presented. This technique employs the resistence strain gauges in touch of the battery case and to detect the minimal change in the battery deformation due to the increasing internal pressure, electrode expantion or intrenal temperature rise. Application of the technique for the study of the effects of the battery processing factors on the battery performance is described taking Ni MH battery as example.


Lithiun Insertion In Carbon Nanotubes, Guotao Wu, Chunsheng Wang, Zhongfu Qi, Wenzhu Li Aug 1998

Lithiun Insertion In Carbon Nanotubes, Guotao Wu, Chunsheng Wang, Zhongfu Qi, Wenzhu Li

Journal of Electrochemistry

Carbon nanotubes were produced by chemical vapour deposition(CVD) of acetylene under hydrogen gas.The reversible specific capacity of carbon nanotubes is up to 700 mAh/g, much higher than the theoretical specific capacity of graphite(372 mAh/g).After twenty charge/discharge cycles,the discharge capacity of carbon nanotube anode still maintains 65.3% of its original discharge capacity . Besides, the charge/discharge efficiency of carbon nanotube in the first charge/discharge cycle was found to improve from 42.6% up to 55.9% by coating carbon nanotubes with copper.


Electrooxidation Of Benzene To Benzoquinone In A Packed Bed Reactor, Xinsheng Zhang, Ping Ding, Yingchun Dai, Weikang Yuan Aug 1998

Electrooxidation Of Benzene To Benzoquinone In A Packed Bed Reactor, Xinsheng Zhang, Ping Ding, Yingchun Dai, Weikang Yuan

Journal of Electrochemistry

A packed electrode reactor was used to oxidize to benzoquinone. Anode bed of the reactor has a size of 10~30 mm×450 mm×50 mm(thickness×length×width),and was packed porous lead alloy. A dispersion of benzene in 1 mol/L aqueous sulfuric acid was passed through the reactor. Current efficiency for benzoquinone generation is 62.9% at optimal operating condition: velocity of electrolyte flow, 0.19 ms -1 ;current, 10 A; thickness of anode bed, 10 mm, and percentage of benzene, 24%.


Studies On The Electrode Kinetics Of Electrooxidation Of Mn 2+, Wanli Hu, Tong Su, Wei Guo, Ding Zhou Aug 1998

Studies On The Electrode Kinetics Of Electrooxidation Of Mn 2+, Wanli Hu, Tong Su, Wei Guo, Ding Zhou

Journal of Electrochemistry

The mechanism of electrooxidation of MnSO 4 on Pb Sb As alloy anode was investigated by using rotating disc electrode technique. The results shown that the conditional standard potential of Mn(Ⅲ)/Mn(Ⅱ)in 40% H 2SO 4 is 0.886 4 V.The rate controlling step of electrode process is mixed controlled by charge transfer and diffusion.


Study Of Proton Exchange Membrane Fuel Cells(Pemfc), Shanhai Ge, Baolian Yi, Hongfen Xu, Ming Han, Zhigang Shao Aug 1998

Study Of Proton Exchange Membrane Fuel Cells(Pemfc), Shanhai Ge, Baolian Yi, Hongfen Xu, Ming Han, Zhigang Shao

Journal of Electrochemistry

The electrode kinetic parameters for proton exchange membrane fuel cells(PEMFC) were investigated by measuring the relations of cell potential and current density. An experimental stack of PEMFC which can be operated at E cell =0.7V, I =0.55A/cm 2 steadily is presented, and the effects of electrode structure and operation conditions such as temperature, pressure, humidification, flow rate on the performance of PEMFC are discussed.


Photoelectrochemical Studies On Nanoporous Tio 2/Pan Film Electrode, Minsheng Liu, Yanzhong Hao, Xuebin Qiao, Maizhi Yang, Shengmin Cai Aug 1998

Photoelectrochemical Studies On Nanoporous Tio 2/Pan Film Electrode, Minsheng Liu, Yanzhong Hao, Xuebin Qiao, Maizhi Yang, Shengmin Cai

Journal of Electrochemistry

The photon to electricity conversion process of nanoporous TiO 2/PAn film electrode was studied in electrolytes with and without redox couple by using the photocurrent action spectra and potential dependence of photocurrent. It is concluded that the nanoporous TiO 2/PAn film electrode has a structure of duplex n type semiconductor layers. The band gap of PAn film is 2.88eV.The TiO 2 nanoporous film electrode modified by PAn can extend the range of optical absorption into visible and infrared region and effectively increase the photocurrent in the visible and infrared region. The photocurrent threshold shifts to>600nm and conversion efficiency of …


Studies Of Surface Alloy As High Efficient Electrocatalyst For Glyoxylic Acid Synthesis, Shengpei Chen, Shengqing Xia, Shigang Sun May 1998

Studies Of Surface Alloy As High Efficient Electrocatalyst For Glyoxylic Acid Synthesis, Shengpei Chen, Shengqing Xia, Shigang Sun

Journal of Electrochemistry

No abstract provided.


Electrochemical Preparation Of Rare Earth Functional Materials And Application Of Rare Earth To Electrochemistry, Qiqin Tong Yexiang Yang May 1998

Electrochemical Preparation Of Rare Earth Functional Materials And Application Of Rare Earth To Electrochemistry, Qiqin Tong Yexiang Yang

Journal of Electrochemistry

The new progress and related mechanism of the electrochemical preparation of rare earth materials(magnets, magnetooptic materials, battery materials, luminescent devices, semiconductors, superconductors) and the application of rare earth to the electrochemical areas(e.g. electroplating,corrosion,electrosynthses) have introduced.


New Esrelectrochemical Cell Designs For Coaxial Microwave Cavity, Lin Lu Juntao Zhuang May 1998

New Esrelectrochemical Cell Designs For Coaxial Microwave Cavity, Lin Lu Juntao Zhuang

Journal of Electrochemistry

New cell designs for simultaneous electrochemical(EC) and electron spin resonance (ESR) measurements are reported for coaxial microwave cavity. Adjustable shieldings are introduced so that the working electrode can be much shorter than the full height of the cavity. Besides the traditional helical electrode, the working electrode can be cylinders made from metal plates, metallic meshes or even composite materials. The counter electrode can be placed either inside or outside the cavity. These features make the new designs more flexible than that previously reported. With a nonperforated cylindrical electrode, this cell can be used to determine the standard potential and the …


Studies On The Transport Properties Of Zn~2+ In The Zn/V_2o_5 Secondary Battery With Aqueous Medium, Jiahong Zhou, Kuanhong Xue, Guping Pan May 1998

Studies On The Transport Properties Of Zn~2+ In The Zn/V_2o_5 Secondary Battery With Aqueous Medium, Jiahong Zhou, Kuanhong Xue, Guping Pan

Journal of Electrochemistry

The transport properties and the reaction mechanism of Zn~2+ in the cathode material of Zn/V_2O_5 secondary battery with aqueous medium were studied by use of intermittent titration experiments and X-Ray diffraction analysis. The relations of some kinetic parameters to the discharge depth were discussed. The results of the experiments show that the cathodic discharge reaction is an intercalation process.


InSitu Raman Spectroscopic Study Of The Oxidation And Reduction Of Ag Electrode In Na_2so_4 Solution, Chen Y X, Huang K Q, Tian Z Q May 1998

InSitu Raman Spectroscopic Study Of The Oxidation And Reduction Of Ag Electrode In Na_2so_4 Solution, Chen Y X, Huang K Q, Tian Z Q

Journal of Electrochemistry

Insitu Raman spectroscopy combined with cyclic voltammogram measurements was used to investigate formation of oxygen species at Ag electrode surfaces during the oxidation and reduction process in 0.1 mol/L Na_2SO_4 solution. The time dependent Raman spectra show that at potentials positive of 0.2 V, adsorption of oxygen atom occurs, while at the potentials positive of 0.4 V, some oxygen atoms migrate into subsurface of the Ag electrode and the other form strongly bound oxygen on the surface through chemical bond. At the same potentials, part of the silver atoms are oxidized and form Ag_2SO_4. During the negative potential ex cursion, …


Electrode Process Of Lithium Ions On Aluminum Electrode In Molten Licl-Kcl, Shuzhen Duan, Congsheng Guan, Qingrong Shi, Xindong Wang May 1998

Electrode Process Of Lithium Ions On Aluminum Electrode In Molten Licl-Kcl, Shuzhen Duan, Congsheng Guan, Qingrong Shi, Xindong Wang

Journal of Electrochemistry

The Deposition mechanism of Lithium on aluminium electrode was studied by using linear sweep voltammetry and potential step method. The formation of α-solid solution was controlled by the diffusion of lithium within the aluminium substance. The formation of β-LiAl alloy was limited by the rate of forming the alloy at the legining, and by diffiusion of lithium through the β- LiAl alloy layer was limited by the rate of forming the alloy at the begining, and by the diffusion of lithium through the β-LiAl alloy later. Neucleation polarization for the formation of β-LiAl alloy was observed. This polarization is an …


Progresses In Surface Electrochemistry And Electrocatalysis ——A Review On The 1997 Joint International Meeting Of Electrochemistry And 97′ International Meeting Of Surface Electrochemistry, Shigang Sun Feb 1998

Progresses In Surface Electrochemistry And Electrocatalysis ——A Review On The 1997 Joint International Meeting Of Electrochemistry And 97′ International Meeting Of Surface Electrochemistry, Shigang Sun

Journal of Electrochemistry

The progresses in surface electrochemistry and electrocatalsis reported in the 1997 joint international meeting of electrochemistry and in the 97′ international meeting of surface electrochemistry were reviewed. The main trends described in this paper consisted of 7 aspects: 1) the studies employing single crystal electrodes, 2) the development of in situ methods of diverse spectroscpoy, 3) the innovation of new research techniques, 4) the preparaton of electrocatalyst of high performances, 5) the quantitative studies on kinetics of electrocatalytic reactions, 6) the investigation on the dynamic processes of surface by timeresolved methods, and 7) the theoretical modeling and simulation of surface …


A Preliminary Study On Thin Film Plasticizing Lithium Ion Battery, Quanfeng Dong, Hanxi Yang, Xingping Ai, Xiaohong Hu, Shengxian Li Feb 1998

A Preliminary Study On Thin Film Plasticizing Lithium Ion Battery, Quanfeng Dong, Hanxi Yang, Xingping Ai, Xiaohong Hu, Shengxian Li

Journal of Electrochemistry

A dry polymer electrolyte was made by plasticizing a copolymer matrix and further filling with liquid electrolyte. A thinfilm lithium ion battery based on the dry polymer electrolyte was manufactured and its electrochemical properties were measured. It is found that the thin film lithium ion battery exhibits similar discharge properties to liquid electrolyte battery, and shows strong high rate capability. 


A Study On Heterogeneous Indirect Electrosynthesis Of Benzaldehyde, Daobao Chu, Changjian Lin, Huashui Lin, Jianguang Tan Feb 1998

A Study On Heterogeneous Indirect Electrosynthesis Of Benzaldehyde, Daobao Chu, Changjian Lin, Huashui Lin, Jianguang Tan

Journal of Electrochemistry

Heterogeneous indirect electrosynthesis process of benzaldehyde has been investigated using cyclic voltammetry and polarization curves. An optimum condition for preparation of benzaldehyde by indirect electrooxidation of toluenc with redox Mn~3+/Mn~2+ is given in this paper. Electrolytic regeneration Mn~3+ are made at Pt/Ti anode in “slurry” MnSO_4/H_2SO_4 medium. Current efficiency for electrolytic regeneration Mn~3+ was maintained over 88% by “double cyclic way”.


Investigation Of Methanol Anode Electrooxidation Catalysts, Gangyao Wen, Ying Zhang, Zhenglong Yang, Changzhi Li Feb 1998

Investigation Of Methanol Anode Electrooxidation Catalysts, Gangyao Wen, Ying Zhang, Zhenglong Yang, Changzhi Li

Journal of Electrochemistry

A series of catalysts, Pt-WO_3/C, Pt/Ru/C and Pt-Ru-WO_3/C were prepared by chemical reduction deposition. Electrocatalytic oxidation of methanol on different catalyst/Nafion membrane electrodes was studies by cyclic voltammetry and currentpotential polarization. The results indicated that the catalytic activity order of different catalysts is as follows: Pt-Ru-WO_3/C>Pt-Ru/C>Pt-WO_3/C. At the same time, influences of methanol concentrations and catalyst proportion on performances of anodes were also studies.


Study On Nano Electrode Material Of Lithium Ion Batteries, Jinkua You, Yong Yang, Dong Shu, Shenghui Wu, Yingchun Zhang, Zugeng Lin Feb 1998

Study On Nano Electrode Material Of Lithium Ion Batteries, Jinkua You, Yong Yang, Dong Shu, Shenghui Wu, Yingchun Zhang, Zugeng Lin

Journal of Electrochemistry

In this paper, the structure and morphology of the nano phase electrode materials have been characterized with XRD and TEM. The performances of electrochemical intercalation and deintercalation of lithium ions have been studied by using cyclic voltammograms and galvanostatic charge discharge techniques. The results show that the nano materials posses advantage of micro structure and Li+ ions intercalation performances. The observed high capacity and large charge discharge current density of the nano phase materials seem to have resulted from three kinds of effects: 1) an increase in the space for Li+ ions intercalation; 2) a decrease in the distance for …


Studies Of Surface Electrochemistry And Electrocatalysis At Atomic And Molecule Level, Shigang Sun Feb 1998

Studies Of Surface Electrochemistry And Electrocatalysis At Atomic And Molecule Level, Shigang Sun

Journal of Electrochemistry

The main progresses achieved during last few years in our research group concerning studies of surface electrochemistry and electrocatalysis were reviewed in this present paper. Four topics were described: 1) the surface electrochemistry and model electrocatalysis of metal single crystal planes, 2) the electrocatalytic reaction mechanism and the control of reaction pathways at molecule level, 3) the reaction kinetics of electrooxidation of small organic molecules, and 4) the relationship between the properties and the surface chemical states of electrocatalyst. This review lays in emphasis on the demonstration of the results as well as the research direction of surface electrochemistry and …


The Investigations Of Surface Treatment Methods And Characterization Of Oxide Films On Ab_5Based Metal Hydride Electrodes Ⅰ. New NiRich Treatment Methods And Photoelectrochemical Characterization Of Oxide Films, Junmin Nan, Yong Yang, Jun Li, Zugeng Lin Feb 1998

The Investigations Of Surface Treatment Methods And Characterization Of Oxide Films On Ab_5Based Metal Hydride Electrodes Ⅰ. New NiRich Treatment Methods And Photoelectrochemical Characterization Of Oxide Films, Junmin Nan, Yong Yang, Jun Li, Zugeng Lin

Journal of Electrochemistry

Two simple and efficient surface treatment methods for AB_5type hydrogen storage alloys were developed. The results of X-ray photoelectron spectroscopy (XPS) and cyclic voltammetric (CV) experiments showed that the hydrogen storage alloys treated by two different methods had Nirich surface layer so that the performances of the electrodes were improved after treatment. The characterization of the oxide films which formed on the surface of electrodes through potentiodynamic oxidation with the help of photoelectrochemical microscopy (PEM) were done. The anodic photocurrent and the cathodic photocurrent related to the oxidation of hydrogen and the reduction of oxygen on the surface layer were …


Anchor Effect Of Iron And Cobalt To Platinum On Carbon Substrates, Zidong Wei Feb 1998

Anchor Effect Of Iron And Cobalt To Platinum On Carbon Substrates, Zidong Wei

Journal of Electrochemistry

The cathodic reduction of oxygen is studied on porous carbonbased electrodes carrying platinumiron and/or cobalt alloy catalysts. Electrodes using such electrocatalysts, particularly when used as cathodes in acidic electrolytes, remain stable for longer periods. The cathodic polarization of oxygen reduction on such electrodes is 20 mV to 40 mV lower than that on the conventional electrode on which only platinum alone is used as an electrocatalysts. An accelerated aging test (AAT) is used to evaluate the corrosion resistance and sintering resistance of each catalyst. The dissolution of the catalyst in the AAT filtrate is analysed and provides a measure of …


Study On The Synthesis And Electrochemical Behavior Of Poly (QuinonoidDisulfide), Xiaohui Tang, Xiuwu Sun, Yongfang Li, Shibi Fang Feb 1998

Study On The Synthesis And Electrochemical Behavior Of Poly (QuinonoidDisulfide), Xiaohui Tang, Xiuwu Sun, Yongfang Li, Shibi Fang

Journal of Electrochemistry

Organic polydisulfide containing quinonoid structure was synthesized by chloromethylation, oxidation by nitric acid, and condensation polymerization with sodium disulfide. The effect of quinonoid structure on the electrochemical behavior of organic polydisulfide was investigated with cyclic voltammetry and chargedischarge measurement. The result shows that quinonoid struture mainly affects the positions of redox peaks of organic polydisulfide, open circuit voltage and discharge platform voltage of cell with the organic polydisulfide as cathode.