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Articles 751 - 780 of 860

Full-Text Articles in Physical Chemistry

Adsorption And Oxidation Of Methanol On Pt And Sb, S Modified Pt Electrodes Using Cyclic Voltammetry And Eqcm, Guo-Liang Chen, Sheng-Pei Chen, Heng Lin, Xing-Hong Zheng, Shi-Gang Sun Nov 2001

Adsorption And Oxidation Of Methanol On Pt And Sb, S Modified Pt Electrodes Using Cyclic Voltammetry And Eqcm, Guo-Liang Chen, Sheng-Pei Chen, Heng Lin, Xing-Hong Zheng, Shi-Gang Sun

Journal of Electrochemistry

The processes of adsorption and oxidation of methanol on Pt, Pt/Sb ad and Pt/S ad electrodes were studied by using cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM). The results demonstrated that the oxidation of methanol depends strongly on oxidation states of electrode surface. Sb adatoms on Pt surface can adsorb oxygen at relatively low potentials, and exhibit catalytic effects for methanol oxidation. In contrast to Pt electrodes, the oxidation peak potential of methanol in this case negatively shifted to about 130 mV. In a contrary, the oxidation of Sad atoms consumes oxygen species of Pt electrode surface. As …

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Performance Of Proton Exchange Membranefuel Cell With Co/H2 Fuel, Hong-Mei Yu, Zhong-Jun Hou, Bao-Lian Yi, Ke-Wan Bi, Jing-Xin Zhang, Zhi-Yin Lin, Ming Han May 2001

Performance Of Proton Exchange Membranefuel Cell With Co/H2 Fuel, Hong-Mei Yu, Zhong-Jun Hou, Bao-Lian Yi, Ke-Wan Bi, Jing-Xin Zhang, Zhi-Yin Lin, Ming Han

Journal of Electrochemistry

Fuel of proton exchange membrane fuel cell(PEMFC) mostly comes from reformatecontains CO which will poison the fuel cell electrocatalyst. The effect of CO on the performance of PEMFC was studied in this paper. The results of the experiment show that when CO is fed inPEMFC ,the cell voltage will be decreased violently,then it will become steady with some vibration. The poison will become more serious with higher CO content and weaker at higher temperature. The adsorption of CO on the electrocatalyst is reversible. The PtRu electrocatalyst is moresuitable for the electrocatalysis of CO/H2 than Pt electrocatalyst.

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Study Of The Oxidation Dynamics Of Tizro2 Metal-Ceramics, Wen-Chao Li, Li-Dong Teng May 2001

Study Of The Oxidation Dynamics Of Tizro2 Metal-Ceramics, Wen-Chao Li, Li-Dong Teng

Journal of Electrochemistry

The oxidation dynamics of hot-pressed Ti-ZrO2 metal-ceramics with the compositionof 50 vol.% Ti and 50 vol.% ZrO2 has been studied.Thermodynamic analysis shows that Ticould react with O2 but not with N2 in the oxidizing process of TiZrO2 composites at 0.1 MPa air. The oxidation dynamic behavior of Ti-ZrO2 composites is analogous to that of pure Ti. Theactivation energy for the oxygen diffusion in Ti-ZrO2 composites is higher than that in Ti solutions, for the presence of ZrO2 restrains the oxygen diffusion in Ti-ZrO2 composites. At early stagethe oxidation of Ti-ZrO2 …

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Performance Of A Direct Methanol Fuel Cell, Zhao-Bin Wei, Jian-Guo Liu, Ya-Guang Jiao, Wei-Jiang Zhou, Wen-Zhen Li, Li-Kang Chen, Qin Xin, Bao-Lian Yi May 2001

Performance Of A Direct Methanol Fuel Cell, Zhao-Bin Wei, Jian-Guo Liu, Ya-Guang Jiao, Wei-Jiang Zhou, Wen-Zhen Li, Li-Kang Chen, Qin Xin, Bao-Lian Yi

Journal of Electrochemistry

A direct methanol fuel cell with 9cm2 active area consists of Pt-Ru/C anode ,Pt/Ccathode and Nafion 115 membrane. The effect of operating conditions: methanol solution concentration, oxygen pressure and cell temperature on the cell performances was investigated. The results show that performance of single cell was enhanced by increasing oxygen pressure and celltemperature ,and a maximum power density 75 mW/cm2 was obtained in the range of 250-300mA/cm2 current density, 0.2 MPa oxygen pressure, 1.0 mol/L methanol concentration and 75 ℃ cell temperature. When cell operating at room temperature, a relatively low, but a stable performance of cell …

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New Progress In Studies Of Lithium Nickel Oxide As Positive Electrode Materials Of Lithium Ion Batteris, Han-San Liu, Yong Yang, Zhong-Ru Zhang, Zu-Geng Lin May 2001

New Progress In Studies Of Lithium Nickel Oxide As Positive Electrode Materials Of Lithium Ion Batteris, Han-San Liu, Yong Yang, Zhong-Ru Zhang, Zu-Geng Lin

Journal of Electrochemistry

Lithium nickel oxide as the positive electrode of lithium ion batteries has aroused more and more interests.This paper reviews the recent reserches on synthesis and element-substitution of LiNiO2 cathode material,and summarizes the intrinsical relationship between properties and sturcture of the material.The developments of new synthesis methods and mutilsubstitution of the material are expecting to be studied in the future research.

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A Study On The Performance Of Matrix Prepared By Tape Cast And Its Molten Carbonate Fuel Cells (Mcfcs), Hua-Xin Lin, Bao-Lian Yi, Li Zhou, Chang-Qing He, Lian-Ying Kong, En-Jun Zhang Feb 2001

A Study On The Performance Of Matrix Prepared By Tape Cast And Its Molten Carbonate Fuel Cells (Mcfcs), Hua-Xin Lin, Bao-Lian Yi, Li Zhou, Chang-Qing He, Lian-Ying Kong, En-Jun Zhang

Journal of Electrochemistry

The matrix prepared with γ-LiAlO2 powder and by tape cast displayed higher ability of preventing from gas cross over and lower ohmic polarization. The voltages of the stack (three cells, 122 cm2) stacked with the matrix were 2.02 and 1.78 V at 200 and 246 mA/cm2, respectively, and the output power reached 53.4 W. The cell (28 cm 2) voltages were 0.85 and 0.75 V at 200 and 300 mA/cm2, respectively, and the output power was about 6.6 W. Compensating the shrinkage of matrix in stacking cells promoted the enhancement of the …

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The Charge Transfer Effect Of Sers Induced By The Electrochemical Hydrogen Evolution Reaction, Feng-Ming Liu, Qi Han, Yan-Xia Chen, Qi-Ling Zhong, Bin Ren, Zhong-Qun Tian Feb 2001

The Charge Transfer Effect Of Sers Induced By The Electrochemical Hydrogen Evolution Reaction, Feng-Ming Liu, Qi Han, Yan-Xia Chen, Qi-Ling Zhong, Bin Ren, Zhong-Qun Tian

Journal of Electrochemistry

As one of the important mechanisms of SERS, the charge transfer (CT) enhancement requires the strong interaction of the adsorbed species with the substrate in order to permit the transition of charge between the metal Fermi level (energy state) and the molecular orbital. The high enhancement needs the match of the energy gap between the Fermi level (or surface state) and the orbital energy level of the adsorbed molecules with the energy of the incident light. The electrode Fermi level is usually adjusted by the applied potential to satisfy the CT resonance. For the electrochemical reaction process, the frontier orbital …

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How Can Direct Mthanol Fuel Cell Benefit From Carbonate Media, Lin Zhuang, Yang Wang, Jun-Tao Lu Feb 2001

How Can Direct Mthanol Fuel Cell Benefit From Carbonate Media, Lin Zhuang, Yang Wang, Jun-Tao Lu

Journal of Electrochemistry

The kinetics of methanol oxidation and oxygen reduction in 0.5 mol/L K2CO3 were compared with those in 0.5 mol/L H2SO 4. Experiments revealed that carbonate media could be more beneficial to direct methanol fuel cell(DMFC). Firstly, both electrode reactions show better performance in the carbonate than in the acid; secondly, materials other than noble metals become possible to be used as the anodic and cathodic catalysts; thirdly, the potential dectease caused by methanol crossover could be depressed by using metal oxide catalysts not stable in acid, such as MnO2.

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Synthesis Of Limn2O4-ΔClΔ Cathode Material By Like-Sol-Gel Methode, Zhao-Yong Chen, Yi He, Xing-Quan Liu, Zhi-Jie Li, Zuo-Long Yu Feb 2001

Synthesis Of Limn2O4-ΔClΔ Cathode Material By Like-Sol-Gel Methode, Zhao-Yong Chen, Yi He, Xing-Quan Liu, Zhi-Jie Li, Zuo-Long Yu

Journal of Electrochemistry

LiMn2O4-δClδ was synthesized by like sol gel methode, with calculated LiOH·H2O, Mn(No3)2⋅6H2O and LiCl·H2O, and made electrochemical test with these compounds as positive materials. Result demostrated that LiMn2O4-δClδ cathode material has exellent stability and nearly no capacity loss after reaching stability.

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Adsorption And Oxidation Of Ethanol On Nm-Pt/Gc Electrode Ii. Eqcm And In-Situ Ftir Spectroscopic Studies In Acid Media, Guo-Liang Chen, Sheng-Pei Chen, Zhi-You Zhou, Chun-Hua Zhen, Shi-Gang Sun Feb 2001

Adsorption And Oxidation Of Ethanol On Nm-Pt/Gc Electrode Ii. Eqcm And In-Situ Ftir Spectroscopic Studies In Acid Media, Guo-Liang Chen, Sheng-Pei Chen, Zhi-You Zhou, Chun-Hua Zhen, Shi-Gang Sun

Journal of Electrochemistry

The adsorption and oxidation of ethanol on nm Pt/GC electrode in acid solutions containing 0.1 mol·L -1 H2SO4 +0.1 mol·L -1 CH3CH2OH was investigated by using cyclic voltammetry, EQCM and in situ FTIR spectroscopy. The experimental results demonstrated that the oxidation of CH3CH2OH is closely relaed to solution acidity and oxygen species on electrode surface; CH3CH2OH was oxidized on nm Pt/GC electrode in acidic media via a dual path reaction mechanism, i.e . CH3CH2OH may be oxidized into CO2 through …

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Effects Of External Electric Field On The Interfacial Properties Of Weakly Dipolar Fluid, V. B. Warshavsky, T. V. Bykov, Xiao Cheng Zeng Feb 2001

Effects Of External Electric Field On The Interfacial Properties Of Weakly Dipolar Fluid, V. B. Warshavsky, T. V. Bykov, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

In the framework of modified mean-field density-functional theory, effects of a uniform electric field on the interfacial properties of a model dipolar fluid are studied. Both density and orientational order-parameter profiles of the planar vapor-liquid interface are obtained as a function of the field strength. For the dipolar fluids with reduced dipole moment μ0*0*E*/T*!1) can shift the surface tension by few percent. We also find that the electric field actually reduces the thermodynamical surface tension but enhances the mechanical surface tension at the equimolar dividing surface. To detect these field effects on …

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The Development Of Carbon Monoxide Tolerant Catalysts For Proton-Exchange Membrane Fuel Cell, Zhong-Jun Hou, Hong-Mei Yu, Bao-Lian Yi, Ming Han Nov 2000

The Development Of Carbon Monoxide Tolerant Catalysts For Proton-Exchange Membrane Fuel Cell, Zhong-Jun Hou, Hong-Mei Yu, Bao-Lian Yi, Ming Han

Journal of Electrochemistry

High over-potential of proton exchange membrane fuel cell (PEMFC) anode caused by carbon monnoxide poisoning when reformate or methanol is used as fuel is main obstacle to the high performance of PEMFCs. Using carbon monoxide tolerant catalysts is the most hopeful way to solve the CO problem. The CO poisoning problem is reviewed briefly in this paper, and the development of CO tolerant catalysts is introduced in details, including electrocatalysts activity, preparation method and mechanism of tolerance to CO.Mo and W can improve catalysts' CO tolerance. Multi-component catalysts are expected to be more tolerant to CO.

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Template Synthesis Of Nano-Structured Electrode Materials And Its Electrochemical Performance, Jian Zhao, Quan-Yong Gao, Yong Yang, Zu-Geng Lin Nov 2000

Template Synthesis Of Nano-Structured Electrode Materials And Its Electrochemical Performance, Jian Zhao, Quan-Yong Gao, Yong Yang, Zu-Geng Lin

Journal of Electrochemistry

In this letter, various nano structured materials such as spinel LiMn2O4 nanotubes/nanowires and carbon nanotubes have been prepared by using porous alumina template. The prepared template and materials have been characterized by AFM and TEM techniques. It is shown that size of the nanotubes can be conveniently controlled by using template method. Some preliminary results of cyclic voltammetry about nano structured LiMn2O4 are also reported.

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Studies Of Adsorption And Oxidation Of Ethanol On Nm-Pt/Gc Electrode——I. Cyclic Voltammograms And In-Situ Ftir Spectroscopy In Alkaline Media, Guo-Lian Chen, Shi-Gang Sun, Sheng-Pei Chen, Zhi-You Zhou Nov 2000

Studies Of Adsorption And Oxidation Of Ethanol On Nm-Pt/Gc Electrode——I. Cyclic Voltammograms And In-Situ Ftir Spectroscopy In Alkaline Media, Guo-Lian Chen, Shi-Gang Sun, Sheng-Pei Chen, Zhi-You Zhou

Journal of Electrochemistry

The electro-oxidation of ethanol on nm-Pt/GC electrode in alkaline solutions containing 0.02 mol·L-1 NaOH+0.1 mol·L-1 CH3CH2OH was investigated by using cyclic voltammetry and in-situ FTIR spectroscopy. The experimental results demonstrated that the main product of ethanol oxidation is CH3COO-, only very small amount of CH 3CHO has been determined simultaneously. In contrast with the dual path reaction mechanism for the oxidation of ethanol in acid media, the oxidation of ethanol in alkaline media didn't pass through the dissociative adsorption, and no adsorbed species could be determined even using a …

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Investigation Of A Complex Lithium Cobalt Nickel Oxide As Lithium Ion Battery Cathode Materials Prepared By A New Citrate Sol-Gel Method, Jing-Li Han, Qing-Guo Liu Nov 2000

Investigation Of A Complex Lithium Cobalt Nickel Oxide As Lithium Ion Battery Cathode Materials Prepared By A New Citrate Sol-Gel Method, Jing-Li Han, Qing-Guo Liu

Journal of Electrochemistry

The synthesis and electrochemical characteristics of lithium cobalt nickel oxide as cathode materials for rechargeable lithium batteries were investigated. It was clarified from these investigations that lithium cobalt nickel oxide has been produced from basic cobalt carbonate,basic nickel carbonate, lithium carbonate, and citrate. LiNi0.8Co 0.2O2 prepared under the stream of oxygen gas showed a higher cycling capacity of (～190 mAh·g-1).

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Fourier Transform Raman Spectroscopy For Process Control In The Petroleum Industry, Kent Lawson Wise Oct 2000

Fourier Transform Raman Spectroscopy For Process Control In The Petroleum Industry, Kent Lawson Wise

Chemistry & Biochemistry Theses & Dissertations

As early as 1950, Raman spectroscopy was proposed as a method to determine aromatics and olefins in hydrocarbon mixtures. Until recently, extensive use of Raman spectroscopy in the characterization of hydrocarbons has not been practical due to several limitations. One early limitation to Raman analysis was the absence of a high intensity and stable excitation source. This problem has been overcome with the advent of lasers. Another limitation was the presence of fluorescence in hydrocarbon fuels when excited by visible lasers. However, the development of Fourier-transform Raman spectrometers now allows Raman spectra to be collected using near-IR lasers (e.g …

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The Electro-Catalytic Oxidation Of Hcooh On Electrodeposited Pd Electrode, Quan Zhou, Cun-Zhong Zhang, Xiao-Lin Lu, Zhong-Da Wu Aug 2000

The Electro-Catalytic Oxidation Of Hcooh On Electrodeposited Pd Electrode, Quan Zhou, Cun-Zhong Zhang, Xiao-Lin Lu, Zhong-Da Wu

Journal of Electrochemistry

The coherent electroplates were prepared by electro depositing Pd on supporting materials glassy carbon. The surface morphology of the electrodes was examined by SEM. The electro oxidation of HCOOH in HClO4 solution was investigated by using cyclic voltammetry. The results show that the deposited conditions in the preparation of electrodes by electro depositing Pd affect the electrodes electro catalytic activity to the oxidation of HCOOH. The platinized Pd electrode on GC substrates using large current density is of higher catalytic activity to the oxidation of HCOOH than Pd electrode. The electro catalytic activity of PdO formed on the Pd …

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The Effect Of Anode Thickness In Sofcs With Anode Supported Ysz Film, Yi-Huang Zhang, Yi Jiang, Zi-Gui Lu, Yong-Lai Dong, Jing-Wang Yan Aug 2000

The Effect Of Anode Thickness In Sofcs With Anode Supported Ysz Film, Yi-Huang Zhang, Yi Jiang, Zi-Gui Lu, Yong-Lai Dong, Jing-Wang Yan

Journal of Electrochemistry

Solid oxide fuel cells with supported yttria stabilized zirconia electrolyte films on anode substrates of various thickness have been fabricated. The electrochemical performances of the SOFCs have been examined. The results showed that the cell performance was limited by the anodic overpotential, which is caused mainly by a concentration polarization when the anode substrate is thick. The anodic overpotential was reduced obviously as the thickness of anode substrate was decreased. As a result, the performance of the SOFC cell was improved. With a 0.5 mm anode substrate, a SOFC cell produced a power density about 0.19 W/cm2 at 800 …

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A New Method For The Preparation Of The Electrodes With Very Low Platinum Loading Used In Proton Exchange Membrane Fuel Cell, Zhi-Gang Shao, Bao-Lian Yi, Ming Han, Ya-Guang Qiao, Hao Liu, Jing-Rong Yu Aug 2000

A New Method For The Preparation Of The Electrodes With Very Low Platinum Loading Used In Proton Exchange Membrane Fuel Cell, Zhi-Gang Shao, Bao-Lian Yi, Ming Han, Ya-Guang Qiao, Hao Liu, Jing-Rong Yu

Journal of Electrochemistry

Research and development on low platinum loading electrode is very important in reducing the cost of proton exchange membrane fuel cell(PEMFC) stack. This paper has put forward a new method to prepare the electrode of PEMFC. The pore forming substances were used in this methd. The low platinum loading electrodes (0.02 mgPt⋅cm-2) have already been prepared with the method. Compared with the traditional method, the new method is simple, cheep, and easy to scale up. The superior composition of the electrodes is catalyst: pore forming substance: Nafion= 3:3:1. The performance of a single cell using this …

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Cathodic Indirect Oxidation Of Organic Compounds(Ⅱ)——Cathodic Indirect Epoxidation Of Olefine, Xue-Ying Zhang, Bao-Qiu Cui, Deng-Ping Gu, Wei Li Aug 2000

Cathodic Indirect Oxidation Of Organic Compounds(Ⅱ)——Cathodic Indirect Epoxidation Of Olefine, Xue-Ying Zhang, Bao-Qiu Cui, Deng-Ping Gu, Wei Li

Journal of Electrochemistry

We described a novel cathodic indirect epoxidation system in which O2 was first cathodically reduced to H2O2. Then VO(acac)2 was oxidized by H2O2 homogeneously to VO(acac)2OOH which was used to epoxidize some olefine such as maleic, fumaric and crotonic acids. Many affecting factors on the current efficiency were optimized. The research will contribute to the developments of organic electrosynthesis.

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The Study On Lithiated Titanium Composite Oxides As Negative Electrode For Lithium-Ion Battery, Xiao-Yan Yang, Shou-Nan Hua, Shu-Yong Zhang Aug 2000

The Study On Lithiated Titanium Composite Oxides As Negative Electrode For Lithium-Ion Battery, Xiao-Yan Yang, Shou-Nan Hua, Shu-Yong Zhang

Journal of Electrochemistry

Lithiated titanium composite oxides Li4Ti5O12 were prepared from Li2CO3 and TiO2. The XRD results of this composite oxides indicated that the compound had a spinel structure. The electrochemical behavior of lithiated titanium composite oxides was examined. The results showed that this material had an excellent cyclic capability and reversibility for lithium insertion, and had high specific capacity: the initial discharge capacity was 300 mAh·g-1 , and the reversible capacity was 100 mAh·g-1 . The discharge plateau (about 1.5 V) and the charge plateau (about 1.6 V) were very …

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Synthesis Of Li1+XMn2O4 Cathode Material For Lithium-Ion Batteries With Solution Method, Pei-Song Liu, Sing-Quarn Liu, Qing Li, Zhao-Yong Chen, Bai-Lan Zhang, Zuo-Long Yu Aug 2000

Synthesis Of Li1+XMn2O4 Cathode Material For Lithium-Ion Batteries With Solution Method, Pei-Song Liu, Sing-Quarn Liu, Qing Li, Zhao-Yong Chen, Bai-Lan Zhang, Zuo-Long Yu

Journal of Electrochemistry

The cathode materials Li1+xMn2O4 were prepared with citric acid complexing and solution impregnating methods. Structure characterization and specific surface area test were performed by means of XRD, BET methods, the influences of calcination temperature, Li/Mn molar ratio and raw materials on the structure and electrochemical capacity of samples have beem examined. The results showed that the Li/Mn molar ratio and calcimation temperature were the key factors affecting the electrochemical capacity of cathode materias. The optimum conditions for synthesis of  Li1+xMn2O4 cathode material were 0≤x≤0.05 and calcined at 750°C. The initial …

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Powder Microelectrode Modified With Nafion-Os(Bpy)3Â 2+ And Pvp Composite And Its Catalysis For No2- Reduction, Pei-Fang Liu, Jia-Wei Yan May 2000

Powder Microelectrode Modified With Nafion-Os(Bpy)3Â 2+ And Pvp Composite And Its Catalysis For No2- Reduction, Pei-Fang Liu, Jia-Wei Yan

Journal of Electrochemistry

The modified powder microelectrode was prepared by etching a Pt (0.1 mm diameter) disk microelectrode and filling in thus formed cavity with Nation-Os(bpy)32+/PVP composite modified carbon powder. The composite modified powder microelectrode showed cyclic voltammetric behaviors changing with the mole ratio (denoted X) of SO3- to Os(bpy)32+ in Nafion. When X=3, a single pair of current peaks appeared near 0.6V (vs. SCE) due to Os(bpy)32+/3+ redox couple. In contrast, for X=20, a pair of additional current peaks occurred near 0.4V. Both X=3 and X=20 modified powder microelectrodes strongly catalyzed the first …

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Template Synthesis And Uv-Vis Absorption Spectra Of The Nanowire Arrays Of Cadmium Chalcogenides, Shi-Min Xu, Kuan-Hong Xue, Jing-Lin Kong, Dong-Mei Sun, Yu-Ying Feng, Hai-Yan Lu, Guang-Hou Wang May 2000

Template Synthesis And Uv-Vis Absorption Spectra Of The Nanowire Arrays Of Cadmium Chalcogenides, Shi-Min Xu, Kuan-Hong Xue, Jing-Lin Kong, Dong-Mei Sun, Yu-Ying Feng, Hai-Yan Lu, Guang-Hou Wang

Journal of Electrochemistry

The porous alumina membrane formed in the anodic oxidation of highly pure aluminum foil has attracted a great deal of attention in recent years. It can be served as a desired template to prepare nanometer scale materials due to its unique structure of discrete and cylindrical nanopores, paralleled one another, with the homogeneous size and distribution. Chalcogenide semiconductors have promising prospect in the applications of photovoltaic and photoconducting devices and have been extensively exploited for many years. Olbright and his co-workers studied experimentally and theoretically the optical nonlinearties of CdSxSe1-x-doped glass; Britt and Ferekides reported that …

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Cathodic Indirect Electro-Oxidation——Organic Electro-Synthesis Dimethyl Sulfone, Deng-Ping Gu, Rui-Zhi Wang, Hong-Kun Zhang, Xue-Ying Zhang, Wei Li, Bao-Qiu Cui Feb 2000

Cathodic Indirect Electro-Oxidation——Organic Electro-Synthesis Dimethyl Sulfone, Deng-Ping Gu, Rui-Zhi Wang, Hong-Kun Zhang, Xue-Ying Zhang, Wei Li, Bao-Qiu Cui

Journal of Electrochemistry

A cathodic indirect electro-oxidation system was established for indirect electro-oxidize dimethyl sulfoxide to dimethyl sulfone with electro-eduction generated H2O2 catalyzed by the pertungstate/tungstate (WO52-/WO42-) redox mediator. Influences of current density, pH, temperature, and the current efficiencies etc. On the cathodic indirect electro-oxidation of dimethyl sulfone were investigated for determining optimum reaction conditions. The current efficiency reached more than 70%. Mother-liquid could be recycled to use without pollution.

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Effect Of Different Species Of Cobalt Additive On Performance Of Nickel Hydroxide Electrode, Xian-Xia Yuan, Yin-Dong Wang, Feng Zhan Feb 2000

Effect Of Different Species Of Cobalt Additive On Performance Of Nickel Hydroxide Electrode, Xian-Xia Yuan, Yin-Dong Wang, Feng Zhan

Journal of Electrochemistry

Performances of nickel electrodes when adding or without adding Cobalt in different forms were studied, the results were interpreted by cyclic voltammetry(CV) and electrochemical impedance spectroscope (EIS). It was demonstrated that the additions of Co, CoO, CoO+Co by mechanically mixing with Ni(OH)2 all can improve the performance of nickel electrode to some extent, and when Co is added in the form of CoO the best performance can be obtained. This can be mainly attributed to the fact that three kinds of Co additives all improved the structure of nickel hydroxide and the ability of H+ in electrolyte transporting …

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Studies On Electrochemical Synthesis Of 4,5-Disubstituted-1,2- Benzoquinones And The Reaction Mechanism, Xian-Zhang Bu, Gui-Wu Xiao, Lin Ma, Xing-Chum He, Ling-Quan Gu Feb 2000

Studies On Electrochemical Synthesis Of 4,5-Disubstituted-1,2- Benzoquinones And The Reaction Mechanism, Xian-Zhang Bu, Gui-Wu Xiao, Lin Ma, Xing-Chum He, Ling-Quan Gu

Journal of Electrochemistry

The oxidation peak potentials (Ep) of alinine derivates and catechol in 0.1 mol/L KCl+15% alcohol solution were measured by cyclic voltammograms technique. The electrochemical oxidation condition was set according to the Ep. Three derivates of 4,5-disubstituted -1,2-benzoquinones were prepared via electrochemical oxidation-Michael addition reaction. The possible mechanism of electrochemical oxidation-Michael addition reaction is presented.

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The Study On Fabricating Thin Electrodes For Polymer Electrolyte Membrane Fuel Cells (Pemfc), Yong-Sheng Yang, Jing-Hua Liu, Chang-Peng Liu, Gong-Quan Sun, Chang-Zhi Li, Tian-Hong Lu Feb 2000

The Study On Fabricating Thin Electrodes For Polymer Electrolyte Membrane Fuel Cells (Pemfc), Yong-Sheng Yang, Jing-Hua Liu, Chang-Peng Liu, Gong-Quan Sun, Chang-Zhi Li, Tian-Hong Lu

Journal of Electrochemistry

To lower platinum loading in electrodes for polymer electrolyte membrane fuel cell, a new thin electrode fabrication technique (TEFT) was developed in this work. A series of low Pt loading electrodes with smooth and uniformed surface were fabricated by the TEFT. As a result, the maximum power density of the cell with platinum loading of 1 mg/cm2 and Nafion 117 membrane as electrolyte was up to 0.3 W.cm-2. Moreover, the effects of PTFE and Nafion content in cathodes on the performance of PEMFC with low Pt loading electrodes (1 mg Pt/cm2) were examined systematically.

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Electrochemical Characterization Of Ir-Ta-Ti Metal Oxide Coated Titanium Anodes, Ting-Yong Wang, Li-Kun Xu, Guang-Zhang Chen Feb 2000

Electrochemical Characterization Of Ir-Ta-Ti Metal Oxide Coated Titanium Anodes, Ting-Yong Wang, Li-Kun Xu, Guang-Zhang Chen

Journal of Electrochemistry

Ir-Ta-Ti metal oxide coated titanium anodes of variable composition were prepared by thermal decomposition. Their micro morphorogies and electrochemical properties were characterized by scanning electron microscope, open circuit potential, cyclic voltammetry, consumption rate measurements and accelerated life test. The SEM results indicated that all coatings were of a porous and cracked-mud microstructure influenced greatly by the composition of coatings. The electrochemical measurements showed that the Ir-Ta-Ti ternary oxide-coated anodes exhibited excellent electrochemical activity and electrochemical stability in both acidic media and seawater which were affected by the composition and microstructure of the coatings. Owing to good corrosion resistance and low …

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Fabrication And Examination Of Reduced Temperatrue Solid Oxide Fuel Cell Using A Supported Thin Ysz Electrolyte Substrate, Yi-Huang Zhang, Yong-Lei Dong, Yi Jiang, Zhi-Gui Lu, Jing-Wang Yan Feb 2000

Fabrication And Examination Of Reduced Temperatrue Solid Oxide Fuel Cell Using A Supported Thin Ysz Electrolyte Substrate, Yi-Huang Zhang, Yong-Lei Dong, Yi Jiang, Zhi-Gui Lu, Jing-Wang Yan

Journal of Electrochemistry

By using a cost-effective wet process,dense yttria stabilized zirconia (YSZ) films on Ni-YSZ anode substrates have been prepared successfully. The YSZ film was characterized to be around 10 μm in thickness, sufficiently dense, uniform and crack free. A single solid oxide fuel cell fabricated from the supported YSZ film electrolyte on the anode substrate and a LSM cathode prepared on the YSZ film was tested. The power density reached to 0.1 W/cm2 at 800 ℃, showing a reasonable performance. Further analysis on both electrodes shows that the anodic overpotential was much larger than IR drop (including YSZ resistance and …

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