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Articles 3601 - 3630 of 4488

Full-Text Articles in Chemistry

An Investigation On Microstructure And Performance Of The Recasting Perfluorosulfonated Membrane, Feng-Ling Liu, Rong Zeng, Pei-Jin Li, Pin-Qing Wang, Chang-Hong Zhao Nov 2002

An Investigation On Microstructure And Performance Of The Recasting Perfluorosulfonated Membrane, Feng-Ling Liu, Rong Zeng, Pei-Jin Li, Pin-Qing Wang, Chang-Hong Zhao

Journal of Electrochemistry

The microsturcture and performance of the recasting perfluorosulfonated membrane were investigated by comparison with Nafion. The results indicated that although chemical components of the recasting membrane FYM1150 kept the same as Nafion, the dry FYM1150 differed from dry Nafion membrane in structure, the former possessed some small pores which are not through-holes having a diameter of 50～300 nm while the latter had almost no pores; The mechanical properties of the FYM1150 were better than those of Nafion; The discharge performance at high current density of MEA using FYM1150 membrane as an electrolyte was also better than one using Nafion as …

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Mechanistic Study Of Oxidation Of Hypophosphite On Pt Electrodes By Sniftirs, Tai-Xiang Jiang, Hui-Huang Wu Nov 2002

Mechanistic Study Of Oxidation Of Hypophosphite On Pt Electrodes By Sniftirs, Tai-Xiang Jiang, Hui-Huang Wu

Journal of Electrochemistry

The oxidation of hypophosphite on a polycrystalline platinum electrode was studied by SNIFTIRS and cyclic voltammetry, the in-situ IR spectra were analyzed as a function of Pt electrode potentials in the solution of 0.5 mol/L H2SO4+0.1 mol/L NaH2PO2. It was found that the dissociative adsorption of hypophosphite ions occurs on Pt surface, and the oxidation product is H3PO4, rather than H2PO3- which was considered to produce on Ni electrodes, thereby a new insight into mechanism of hypophosphite oxidation on Pt in acidic media was …

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Preparation And Electrochemical Lithium Intercalation Performance Of Different Shaped Carbon Nanotube, Mao-Hui Chen, Zhen-Cai Huang, Guo-Tao Wu, Jin-Kua You, Zu-Geng Lin Nov 2002

Preparation And Electrochemical Lithium Intercalation Performance Of Different Shaped Carbon Nanotube, Mao-Hui Chen, Zhen-Cai Huang, Guo-Tao Wu, Jin-Kua You, Zu-Geng Lin

Journal of Electrochemistry

In the present work, different shaped carbon nanotubes were produced by the general CVD and the template method at different temperature (600 ℃,700 ℃) with the reaction gas of acetylene. The morphology, structure and the electrochemical lithium intercalation performance were comparatively studied and characterized by TEM, HRTEM, SEM, XRD, Raman techniques and Charge/Discharge Test. It was found that the different preparation methods and temperatures all had an obvious effect on these properties of carbon nanotubes. In our samples, with the increase of preparation temperature, the degree of crystallinity decreased, and the reversible specific capacity increased respectively.

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Nano-Sized Cobalt-Based Oxides As Negative Electrode For Lithium-Ion Batteries, Feng Huang, Zheng-Yong Yuan, Yun-Hong Zhou, Ju-Tang Sun Nov 2002

Nano-Sized Cobalt-Based Oxides As Negative Electrode For Lithium-Ion Batteries, Feng Huang, Zheng-Yong Yuan, Yun-Hong Zhou, Ju-Tang Sun

Journal of Electrochemistry

Nanosized cobalt-based oxide (Co3O4, CoB1.36O2.8 and CoB0.5Al0.1O1.5) samples were prepared by rheological phase method and were tested as anodes in secondary lithium batteries. The cells were cycled between 0.01V and 3.00 V. The best electrochemical performance was obtained from the Co3O4 cell, which retained 95% of its initial capacity (931 mAh/g) after 30 cycles. The doping of B, Al reduced the reversible capacity during the first discharge/charge cycle, and the quantity of reversible capacity reduced with B, Al increasing. The modifying structures at difference …

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Properties Of Domestic Natural Graphite Used For Li-Ion Batteries, Cui-Wei Du, Yu-Juan Zhao, Gang Zhang, Yin-Shun Wu, Qing-Guo Liu Nov 2002

Properties Of Domestic Natural Graphite Used For Li-Ion Batteries, Cui-Wei Du, Yu-Juan Zhao, Gang Zhang, Yin-Shun Wu, Qing-Guo Liu

Journal of Electrochemistry

The structure, physical characteristics and electrochemical properties of the natural graphite produced in Shandong province have been studied. The result of X-ray diffraction showed that the graphite consisted of hexagonal structure and rhombic structure (30% rhombic structure). It was fine crystal graphite. Used as a negative material of Lithium ion battery, the natural graphite showed excellent voltage and high energy capacity, but poor compatibility with electrolyte solution containing propylene carbonate (PC) for its own structure limitation.

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Effect Of Dissolved Oxygen On The Corrosion Behavior Of Coalesced Copper And Stainless Steel-206 In Acetic Solutions, Rong-Zong Hu, Xiong-Cao Zhao, Yu-Hua Weng, Chang-Jian Lin Nov 2002

Effect Of Dissolved Oxygen On The Corrosion Behavior Of Coalesced Copper And Stainless Steel-206 In Acetic Solutions, Rong-Zong Hu, Xiong-Cao Zhao, Yu-Hua Weng, Chang-Jian Lin

Journal of Electrochemistry

Linear sweeping technique and dissolving oxygen sensor were used to study the effect of dissolved oxygen and relating factors on the corrosion behavior of coalesced copper and stainless steel-206 in acetic solutions. It was found: 1. The existing of dissolved oxygen is one of the important factors, which strongly influenced the corrosion behavior of coalesced copper and stainless steel-206 in acetic solution. 2. The existing of dissolved oxygen is benefitial to the preventing stainless steel-206 from corrosion in acetic solutions, but damage to the preventing coalesced copper from corrosion. 3. At the high temperature since the dissolved oxygen was escaping …

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Electrocatalytic Oxidation Of Formic Acid On Molybdate-Modified Platinum Electrode, Jun-Hua Du, Xue-Hui Xu, Hong Li, Hong-Yu Cheng, Wei-Shan Li Nov 2002

Electrocatalytic Oxidation Of Formic Acid On Molybdate-Modified Platinum Electrode, Jun-Hua Du, Xue-Hui Xu, Hong Li, Hong-Yu Cheng, Wei-Shan Li

Journal of Electrochemistry

The electrochemical behavior of molybdates on a platinum electrode in H2SO4 solutions with different H2SO4 concentrations was studied by cyclic voltammetry and double chronoamperometry. Molybdates were reduced to adsorb hydrogen molybdenum bronzes on the platinum electrode in H2SO4 solutions during cathodically potential sweep. The hydrogen molybdenum bronzes were oxidized to different forms of hydrogen molybdenum bronzes with less hydrogen, depending on the H2SO4 concentration. Platinum electrode was modified by these hydrogen molybdenum bronzes. However, this modified electrode was not stable in H2SO4 solutions. The modified …

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Improvement Of The Low Temperature Electrochemical Performance Of Ab5-Type Hydrogen Storage Alloy, Hui Ye, Zhu Wu, Zhi-Lin Li, Hong Zhang Nov 2002

Improvement Of The Low Temperature Electrochemical Performance Of Ab5-Type Hydrogen Storage Alloy, Hui Ye, Zhu Wu, Zhi-Lin Li, Hong Zhang

Journal of Electrochemistry

Optimizing the rare earth composition and doping with boron have been used to improve the low temperature performance of AB5 hydrogen storage alloy. The results show that Ce-rich alloy with a proper amount of boron is suitable for Ni/MH battery with the lower-limit temperature down to 238 K under smaller current density (≤120 mA/g). The improvement of low temperature performance of hydrogen storage alloy is well consistent with its microstructure, thermodynamic and kinetic properties.

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Manufacture Of 1 Kw Molten Carbonate Fuel Cell Stack, Sheng Sui, Xin-Jian Zhu, Zheng-Yu Fan, Guang-Yi Cao Nov 2002

Manufacture Of 1 Kw Molten Carbonate Fuel Cell Stack, Sheng Sui, Xin-Jian Zhu, Zheng-Yu Fan, Guang-Yi Cao

Journal of Electrochemistry

A molten carbonate fuel cell stack with an active area of 240 mm×140 mm consisted of 30 cells. The gas feed system works via interior manifolds, and the stack placed in a couple of self-chest, coupled with a heater at the bottom and other fours surrounded,to keep uniformity of temperature.Under ambient pressure and 650 ℃, fed with hydrogen and air as anode and cathode gases respectively, the stack gave a current density of 150 mA/cm2 at an average cell voltage of 0.7 V. The peak output of the stack was 1.06 kW during its performance of 300 h.

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Fragmentation Processes Following Core Excitation In Acetylene And Ethylene By Partial Ion Yield Spectroscopy, Maria Novella Piancastelli, Wayne C. Stolte, Gunnar Ohrwall, S-W Yu, D. Bull, K. Lantz, Alfred S. Schlachter, Dennis W. Lindle Nov 2002

Fragmentation Processes Following Core Excitation In Acetylene And Ethylene By Partial Ion Yield Spectroscopy, Maria Novella Piancastelli, Wayne C. Stolte, Gunnar Ohrwall, S-W Yu, D. Bull, K. Lantz, Alfred S. Schlachter, Dennis W. Lindle

Chemistry and Biochemistry Faculty Research

Partial ion yield spectroscopy provides a very detailed picture of fragmentation processes following core excitation in isolated molecules. We exploit this potential in the analysis of decay processes following C1s→π and C1s→Rydberg excitations in ethylene and acetylene. We show that the relative intensity of spectral features related to the excitation to empty molecular orbitals or to Rydberg states is a function of the time variation of the fragmentation process. Namely, we see an intensity increase in the Rydberg states compared to the molecular orbitals as the fragmentation process becomes more extensive, a result attributable to the diffuse nature of the …

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Creating Nanocavities Of Tunable Sizes: Hollow Helices, Bing Gong, Huaqiang Zeng, Jin Zhu, Lihua Yuan, Yaohua Han, Shizhi Cheng, Mako Furukawa, Ruben D. Parra, Audrey Y. Kovalevsky, Jeffrey L. Mills, Ewa Skrzypczak-Jankun, Suzana Martinovic, Richard D. Smith, Chong Zheng, Thomas Szyperski, Xiao Cheng Zeng Sep 2002

Creating Nanocavities Of Tunable Sizes: Hollow Helices, Bing Gong, Huaqiang Zeng, Jin Zhu, Lihua Yuan, Yaohua Han, Shizhi Cheng, Mako Furukawa, Ruben D. Parra, Audrey Y. Kovalevsky, Jeffrey L. Mills, Ewa Skrzypczak-Jankun, Suzana Martinovic, Richard D. Smith, Chong Zheng, Thomas Szyperski, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

A general strategy for creating nanocavities with tunable sizes based on the folding of unnatural oligomers is presented. The backbones of these oligomers are rigidified by localized, threecenter intramolecular hydrogen bonds, which lead to well-defined hollow helical conformations. Changing the curvature of the oligomer backbone leads to the adjustment of the interior cavity size. Helices with interior cavities of 10 Å to >30 Å across, the largest thus far formed by the folding of unnatural foldamers, are generated. Cavities of these sizes are usually seen at the tertiary and quaternary structural levels of proteins. The ability to tune molecular dimensions …

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Synthesis And Characterization Of Hydroxyapatite-Collagen Biocomposite Materials, Vuk Uskoković, Nenad Ignjatović, Nadejda Petranović Sep 2002

Synthesis And Characterization Of Hydroxyapatite-Collagen Biocomposite Materials, Vuk Uskoković, Nenad Ignjatović, Nadejda Petranović

Pharmacy Faculty Articles and Research

Hydroxyapatite-collagen composite is a prosperous biomaterial in reconstructive surgery for the reparation of defects within human hard tissue. Within this research, three-dimensional blocks of HAp/collagen composite biomaterial were synthesized by homogenizing the HAp/collagen mixture by cold and hot (T=60oC) pressing (P=49 MPa). The changes in the system were followed by using thermal analysis (DSC & TGA), FT-IR spectroscopy and scanning electron microscopy (SEM). The identification and kinetic analysis of appearing phase transition were done. FT-IR spectrum of the biocomposite shows that neither cold nor hot pressing had significant influence on the individual components of the composite. SEM of the fracture …

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Holographic Analysis Of Diffraction Structure Factors, S. Marchesini, N. Mannella, C. S. Fadley, M. A. Van Hove, J. J. Bucher, D. K. Shuh, L. Fabris, M. J. Press, M. W. West, Wayne C. Stolte, Z. Hussain Sep 2002

Holographic Analysis Of Diffraction Structure Factors, S. Marchesini, N. Mannella, C. S. Fadley, M. A. Van Hove, J. J. Bucher, D. K. Shuh, L. Fabris, M. J. Press, M. W. West, Wayne C. Stolte, Z. Hussain

Chemistry and Biochemistry Faculty Research

We combine the theory of inside-source/inside-detector x-ray fluorescence holography and Kossel lines/x ray standing waves in kinematic approximation to directly obtain the phases of the diffraction structure factors. The influence of Kossel lines and standing waves on holography is also discussed. We obtain partial phase determination from experimental data obtaining the sign of the real part of the structure factor for several reciprocal lattice vectors of a vanadium crystal.

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Thionine-Glutathione Self-Assembly Monolayer Modified Electrdoe And The Quasi-Reversible Response Of Dopamine, Cheng Fang, Zheng Luan, Wu-Ming Zhang, Xing-Yao Zhou Aug 2002

Thionine-Glutathione Self-Assembly Monolayer Modified Electrdoe And The Quasi-Reversible Response Of Dopamine, Cheng Fang, Zheng Luan, Wu-Ming Zhang, Xing-Yao Zhou

Journal of Electrochemistry

Thionine was bound onto a glutathione monolayer self-assembled on the surface of a gold electrode previously, the electrochemical characteristics of which were studied. It was found that dopamine had a quasi-reversible response and cathodic characterstics peak could be used to determine the concentration of dopamine in the range of 1.0～300 μmol·L-1 in the presence of a higher concentration of ascorbic acid.

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Optimum Of Catalyst Layers For Direct Methanol Fuel Cells, Jun Zhang, Lei Li, Li Xu, Yu-Xin Wang Aug 2002

Optimum Of Catalyst Layers For Direct Methanol Fuel Cells, Jun Zhang, Lei Li, Li Xu, Yu-Xin Wang

Journal of Electrochemistry

The performances of membrane electrode assemblies (MEAs)with various Pt loading were compared. The amount of Nafion in a catalytic layer was optimized, and the effect of Nafion loading on the resistance of MEAs was investigated with ac impedance spectroscopy. For a MEA with both Pt 4 mg/cm2 in the anode and the cathode, suitable Nafion loading was 21.4 wt% in the anode. With 21.4 wt% Nafion loading in the cathode, the Direct Methanol Fuel Cells(DMFC) showed the highest performance at high current density. While, the DMFC performances came down, as Nafion loading increasing,for ohm and concentration polarization.

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Electrochemical Properties Of Nitrate Immobilized On Gold Electrodes With 2-Aminoethanethiol Sams, Ya-Ru Song, Hong Wu, Hui-Bo Shao Aug 2002

Electrochemical Properties Of Nitrate Immobilized On Gold Electrodes With 2-Aminoethanethiol Sams, Ya-Ru Song, Hong Wu, Hui-Bo Shao

Journal of Electrochemistry

Nitrate reductase (NR) and phospholipids were immobilized on gold electrodes with 2-aminoethanethio(AET) SAMs. After Au/AET/NR and Au/AET/NR/lipid were soaked in pH 7 phosphate buffers for days, a pair of pre-reversible peak appeared at around 0.202 V and 0.149 V respsctively, irregularly grew with soaking time in blank buffer.The cathodic peak current (ipcl) of Au/AET/NR system had linear relationship with scan rate between 0.02 and 0.5 V⋅s-1 ,while ipcl was proportional to V1/2 in Au/AET/NR/lipid system. The direct electron transfer of enzyme electrodes was strongly affected by pH. Compared with Au/AET, NR exhibited a higher electrochemical …

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Study On Modification Of Spinel Limn2O4 By Overcoating, Ren-Gang Zhang, Shi-Xi Zhao, Jung-Lei Xia, Han-Xing Liu Aug 2002

Study On Modification Of Spinel Limn2O4 By Overcoating, Ren-Gang Zhang, Shi-Xi Zhao, Jung-Lei Xia, Han-Xing Liu

Journal of Electrochemistry

The surface of spinel LiMn2O4 was modified by the sol-gel process with LiCoO2-coated LiMn2O4 and studied by XRD, SEM and EPMA. The results have shown that the surface of the coated grains heated at 700 ℃ for 10h, which is cubic spinel, were Co-rich. The amount of Co3+ in the grains changed owing to different place of the grain and decreased from surface to inner parts. Using the coated as the cathode of Li-ion cells, the initial capacity deceased slightly, but the amount of Mn2+ solving in electrolyte decreased, Jahn-Teller …

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Some Consideration For Lithium-Ion Cells' Safety, Guang-Xia Hu, Jing-Ying Xie Aug 2002

Some Consideration For Lithium-Ion Cells' Safety, Guang-Xia Hu, Jing-Ying Xie

Journal of Electrochemistry

The safety is the most important problem for lithium ion cells, especially for large lithium ion cells. In this paper, some information about lithium ion cells' safety can be learned by discussing several aspects of lithium ion cells, such as, materials of lithium ion cell, manufacturing processes, using conditions and so on.

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Study On Hydrogen Evolution Performance Of Nickel-Tin Electrode, Tian-Yi Chang, Bao-Hong Zhang, Wenbo Cong, Yao Luo Aug 2002

Study On Hydrogen Evolution Performance Of Nickel-Tin Electrode, Tian-Yi Chang, Bao-Hong Zhang, Wenbo Cong, Yao Luo

Journal of Electrochemistry

The cathode active material with low hydrogen evolution overvoltage was prepared by electroplating Ni-Sn alloy on the ferrous basic body.This kind of material can be applied in the diaphragm type of electrolytic tank to decrease cell voltage and save energy. On the condition according with cathode solution in the electrolytic tank (NaOH 120 g/L, NaCl 190 g/L, 90 ℃, i=150 mA/cm2), the overvoltage of hydrogen evolution was 88 mV. By the X-ray diffraction analysis, it was found that the structure of this kind of material was different from that of Ni-Sn alloy applied in traditional decoration. By using …

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Electrochemical Degradation Of Organic Wastewater By Three-Dimensional Electrode Reactor, Chun He, Tai-Cheng An, Ya Xiong, Dong Shu, Hui-Ling Hu, Xi-Hai Zhu Aug 2002

Electrochemical Degradation Of Organic Wastewater By Three-Dimensional Electrode Reactor, Chun He, Tai-Cheng An, Ya Xiong, Dong Shu, Hui-Ling Hu, Xi-Hai Zhu

Journal of Electrochemistry

The electrochemical degradation of aniline was investigated using a novel electrochemical reactor, three-dimensional electrode reactor. The experimental results indicated that the reactor could efficiently remove aniline. The removal efficiency could be attributed to a combination of direct and indirect electrochemical reactions, that is, anodic oxidation and oxidation of electrogenerated H2O2 and hydroxyl radicals generated in electro-Fenton process. It was also observed that the removal efficiency was significantly dependent on applied voltage, Fe2+ concentration, pH value and electrolysis time. In the experimental range they all have a positive effect on the removal efficiency except for pH value. …

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Facilitated K+ Ion Transfer By Db18c6 Across The Micro Liquid/Liquid Interface, Dong-Ping Zhan, Bing-Liang Wu Aug 2002

Facilitated K+ Ion Transfer By Db18c6 Across The Micro Liquid/Liquid Interface, Dong-Ping Zhan, Bing-Liang Wu

Journal of Electrochemistry

A novel microcavity Ag|AgCl electrode was fabricated to construct the micro-interface of two immiscible electrolyte solutions(ITIES). The transfer reactions of K+ ion facilitated by DB18C6 across the water/1,2-DCE interface was investigated with the three-electrodes system. The corresponding reaction parameters were derived from the voltammetric data. The results showed that the microcavity electrode would be a useful and efficient tool to investigate the charge transfer reactions at ITIES.

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Pure Hap Film Prepared By Direct Electrodepositing On Metallic Surface And Its Mechanism, Hao-Bing Hu, Chang-Jian Lin, Fei Chen, Ren Hu, Ming Guo Aug 2002

Pure Hap Film Prepared By Direct Electrodepositing On Metallic Surface And Its Mechanism, Hao-Bing Hu, Chang-Jian Lin, Fei Chen, Ren Hu, Ming Guo

Journal of Electrochemistry

In controlling concentration of Ca2+ and PO43- in electrodeposition solution, the HAP film on Ti alloy has been deposited directly. Using XRD and SEM we have learned that prepared HAP is intact in crystal and equal in dimension. Thermodynamic calculation indicated that the HAP is easer formation of than that TCP of. With the XRD, SEM analyses and thermodynamic calculation, the electrodeposition mechanism has been discussed. It was proved that electrodepositon is a two-stage process and formation of HAP is a direct process from solution ions to HAP crystal without precursor.

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Electrochemical Techniques For Measuring Anti-Corrosion Behavior Of The Thin Corrosion Inhibitor Layer To The 907a Steel, Yong-Tao Zhao, Jian-Hua Wu, Fan-Cai Chen, Zhong-Ping Gao, Jia Wang, Chang-Jiu Zhao Aug 2002

Electrochemical Techniques For Measuring Anti-Corrosion Behavior Of The Thin Corrosion Inhibitor Layer To The 907a Steel, Yong-Tao Zhao, Jian-Hua Wu, Fan-Cai Chen, Zhong-Ping Gao, Jia Wang, Chang-Jiu Zhao

Journal of Electrochemistry

The corrosion inhibiting behavior of 907A steel, which was covered with thin inhibitor layers in moist seawater atmosphere,was studied. The electrochemical measurements, including EIS method and the coulostatic method, were used to atmospheric corrosioed monitor (ACM) under thin inhibitor layers to determine its corrosion rate. The results shown that the application of electrochemical methods such as the coulostatic technique and EIS could readily detect the on going process of film formation. Hence, the rapid evaluation of the thin inhibitor layers for 907A steel might be possible.

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Synthesis And Characterization Of Lini0.8-XAlXCo0.2O2 As Cathodes For Lithium-Ion Batteries, Jun Zhang, Zhong-Kao Jin, Qing-He Yang, Qing-Mei Song, Xiao-Hua Ma, Xiang-Fu Zong Aug 2002

Synthesis And Characterization Of Lini0.8-XAlXCo0.2O2 As Cathodes For Lithium-Ion Batteries, Jun Zhang, Zhong-Kao Jin, Qing-He Yang, Qing-Mei Song, Xiao-Hua Ma, Xiang-Fu Zong

Journal of Electrochemistry

Single-phase solid solution of LiNi0.8-xAlxCo0.2O2 (0≤ x <0.1)had been synthesized and characterized by X-ray diffraction(XRD) and scanning electron microscopy (SEM). Their electrochemical performance was examined by charge-discharge cycling. The LiNi0.71Al0.09Co0.2O2 compound showed a discharge capacity of 152 mAh/g after 20 cycles that corresponds to 97.4% capacity retention. The beneficial effect of co-doping with Al and Co elements was corro-borated by slow scanning cyclic voltammograms(SSCV), electrochemical impedance spectrum (EIS) and differential scanning calorimetry (DSC) data on charged cathodes. These results show that the 2D-character of the crystal lattice was stabilized by co-doping with Al and Co, the phase transitions that occur during deintercalation or intercalation of Li-ions were significantly suppressed, …

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Diffusion Of Hydrogen At Iron Apply For Electrochemical Oscillating Permeation, Li Zhang, Ren-He Yin, Zhan-Mei Sun Aug 2002

Diffusion Of Hydrogen At Iron Apply For Electrochemical Oscillating Permeation, Li Zhang, Ren-He Yin, Zhan-Mei Sun

Journal of Electrochemistry

The diffusion of hydrogen in iron was measured using electrochemical oscillating permeation. Through the samples in the different frequencies, it was found that diffusion of hydrogen at iron is of linear relation with boundary condition, which is the key to Fick's diffusion equation amplitude in the liquor. We can exploit this line relation getting the diffusion of hydrogen at iron.

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Research Progress On Electrode Material In All-Vanadium Redox Battery, Hua Li, Shou-Wen Chang, Chuan-Wei Yan Aug 2002

Research Progress On Electrode Material In All-Vanadium Redox Battery, Hua Li, Shou-Wen Chang, Chuan-Wei Yan

Journal of Electrochemistry

An all-vanadium redox flow storage battery possesses many advantages over conventional storage batteries.The development statue of two types electrode materials (metal and compound type) is introduced in this article.

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Initial Stages Of Copper Electrodeposition On Glassy Carbon Electrode, Ling Huang, Rui Zhang, Min Gu, Fang-Zu Yang, Shu-Kai Xu, Shao-Min Zhou Aug 2002

Initial Stages Of Copper Electrodeposition On Glassy Carbon Electrode, Ling Huang, Rui Zhang, Min Gu, Fang-Zu Yang, Shu-Kai Xu, Shao-Min Zhou

Journal of Electrochemistry

Initial stages of copper electrodeposition on glassy carbon electrode from acid sulphate solutions were studied using cyclic voltammetry and chronoamperometry. The electrolyte solution was a 0.05 mol.L-1 copper sulphate, 1.4～1.8 mol⋅L-1 sulphuric acid containing 1 mg·L-1 2-mercaptobenzoimidazole, Results show that 2-mercaptobenzoimidazole produced an inhibition of the copper deposition, probably related to the adsorption,sulphuric acid promote copper electrodeposition. The initial deposition kinetics corresponded to a model including instantaneous nucleation and diffusion controlled growth.Addition of 2-mercaptobenzoimidazole and sulphuric acid did not change the initial nucleation of copper electrocrystallization, it increased the nucleation rate and the number density of nuclei …

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The Performance And Heat Balance Of The Mcfc Stack With The Power Of 200 W, Hua-Xin Lin, Li Zhou, Bao-Lian Yi, Hua-Ming Zhang, Chang-Qin He Aug 2002

The Performance And Heat Balance Of The Mcfc Stack With The Power Of 200 W, Hua-Xin Lin, Li Zhou, Bao-Lian Yi, Hua-Ming Zhang, Chang-Qin He

Journal of Electrochemistry

The output power of the MCFC stack was 217.6 W under reaction gas pressure, 0.9 MPa/cm2 and utilization of oxidant and fuel gas, 20%. By calculation it was demonstrated that the heat balance state in the stack was kept at 300 mA/cm2 under the utilization of fuel gas and oxidant,20%. The current density in heat balance state was higher than 100 mA/cm2 under the utilization of air+CO2 mixture gas as oxidant and H2+CO2 mixture gas as fuel gas,40% and 60% respectively. If the utilization was increased in the stack, the current density in …

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Xrd Study On Highly Preferred Orientation Cu Electrodeposit, Min Gu, Fang-Zu Yang, Ling Huang, Shi-Bing Yao, Shao-Min Zhou Aug 2002

Xrd Study On Highly Preferred Orientation Cu Electrodeposit, Min Gu, Fang-Zu Yang, Ling Huang, Shi-Bing Yao, Shao-Min Zhou

Journal of Electrochemistry

Copper electrodeposit was obtained in CuSO4+H2SO4 electrolyte solution by electrodeposition and its structure was studied by XRD. The results showed that copper electoddeposits with the highly preferred orientations of (220) and (111) could be obtained at current density 4.0 A/dm2 and 15.0 A/dm2, respectively. The texture coefficient (TC) values were increased by thickness of Cu deposits. The thickness would be, to obtain Cu electrodeposit with (111) highly preferred orientation, about 7 times of that of (220) highly preferred orientation, which indicated that(220) face was easier to be remained than (111) face and …

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Ionic Conduction In Ba0.95Ce0.9Y0.1O3 - Α Solid Oxide And Its Performance In Fuel Cell, Gui-Lin Ma, Ding-Xian Jia, Li-Gan Qiu, Hui Shi, Rong Chen Aug 2002

Ionic Conduction In Ba0.95Ce0.9Y0.1O3 - Α Solid Oxide And Its Performance In Fuel Cell, Gui-Lin Ma, Ding-Xian Jia, Li-Gan Qiu, Hui Shi, Rong Chen

Journal of Electrochemistry

Using Ba0.95Ce0.9Y0.1O3-α as a solid electrolyte and porous platinum as electrodes,hydrogen and oxygen concentration cells and hydrogen-air fuel cell were constructed, respectively. Electromotive forces (MEFs) of the gas concentration cells and I-V characteristics of the fuel cell were detdrmined in the temperature range of 600～1 000 ℃. The Ba0.95Ce0.9Y0.1O3-α exhibited almost the pure protonic conduction under hydrogen gas,and a mixed conduction of oxide-ion and electron hole with oxide-ion transport number of 0.3～0.5 under oxygen gas. It exhibited a mixed conduction of proton and oxide-ion with the …

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