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2004

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Articles 1 - 30 of 165

Full-Text Articles in Chemistry

Electrochemical Behaviours Of Hemoglobin-Ddab-Modified Powder Microelectrode And The Application Of The Powder Microelectrode In Determination Of Nitric Oxide, Zhi-Mou Guo, Huan Liu, Jian Chen, Wen-Ting Zhang Nov 2004

Electrochemical Behaviours Of Hemoglobin-Ddab-Modified Powder Microelectrode And The Application Of The Powder Microelectrode In Determination Of Nitric Oxide, Zhi-Mou Guo, Huan Liu, Jian Chen, Wen-Ting Zhang

Journal of Electrochemistry

The electrochemical behaviours of DDAB-Hb-PME were studied in this paper. The (apparent) surface concentration of Hb was enhanced greatly by using the powder microelectrode (technique). NO reacts with Hb and absorbs on the surface of the modified carbon powder. Therefore, the output of the electrode was enhanced greatly by employing PME with higher reaction surface (area). The sensitivity of DDAB-Hb-PME is 3.1 mA/μmol·L~(-1)·cm~(2), which is much larger than the values obtained with the traditional electrodes. The detection limit is 9 nmol·L~(-1) and the linear response range is 9～100 nmol·L~(-1).

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Investigation Of Pulse Potential-Modulated Coulometry For Co_2 Detection, Hai-Chuan Wang, Bing-Liang Wu Nov 2004

Investigation Of Pulse Potential-Modulated Coulometry For Co_2 Detection, Hai-Chuan Wang, Bing-Liang Wu

Journal of Electrochemistry

A pulse potential-modulated technique was applied to measure the concentration of CO_2 in gas samples. In the first step, an anodic pulse and a consequent cathodic pulse were used to remove the organic pollutant and surface oxide on the surface of the platinized Pt gauze electrode before each experiment. As following, a given potential step was used to reduce the CO_2 into adsorbed intermediate on Pt surface, and the adsorbates produced were oxidized by a following anodic potential step. At same time the oxidation current of adsorbates were measured. A certain relation exists between the concentration of CO_2 and the …

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Electrocatalytic Performances Of Carbon Nanotube Air Electrode For Oxygen Reduction, Feng-Ming Zhao, Chun-An Ma Nov 2004

Electrocatalytic Performances Of Carbon Nanotube Air Electrode For Oxygen Reduction, Feng-Ming Zhao, Chun-An Ma

Journal of Electrochemistry

The air electrodes with different mass ratio of Pt/active carbon or carbon nanotube as catalyst layer material have been prepared. The electrocatalytic performances for oxygen reduction were evaluated by means of polarization curve and electrochemical impedance spectroscopy (EIS). The results disclosed that carbon nanotubes dealt with nitric acid in the catalyst layer had been improved obviously on the electrocatalytic activity. After the surface of carbon nanotube was oxygenated and aggraded with platinum, the catalyst had obviously effects on the electrocatalytic activity. The air electrode with the mass ratio of active carbon to Pt/carbon nanotube in 4∶1 showed better electrocatalytic activity, …

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Electrochemical Investigations On Pitting Susceptibility Of Iron-Based Alloy, Wei-Shan Li, Hong-Yu Chen, Zhong-Zhi Yuan, Hong Li, Qi-Ming Huang, Dong-Sheng Lv Nov 2004

Electrochemical Investigations On Pitting Susceptibility Of Iron-Based Alloy, Wei-Shan Li, Hong-Yu Chen, Zhong-Zhi Yuan, Hong Li, Qi-Ming Huang, Dong-Sheng Lv

Journal of Electrochemistry

The formation process of passive film on iron and electronic properties and pitting susceptibility of an iron-based alloy are investigated by using linear potential sweep, alternative current impedance and electrochemical nose technologies. The relationship between reciprocal square capacitance and potential following the Mott-Schottky behavior is limited at a narrow rang of low potentials. At higher potentials, linear relationship between reciprocal capacitance and potential is obtained, which is ascribed to the increasing thickness of the passive film with potential. The donor density of the passive film is influenced by the formation potential of the film, passivator and microstructure. The decrease in …

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Anodic Dissolution Of Aluminum In Koh-Ethanol Solutions, Hai-Bo Shao, Jian-Ming Wang, Xiao-Yan Wang, Yi Zheng, Jian-Qing Zhang Nov 2004

Anodic Dissolution Of Aluminum In Koh-Ethanol Solutions, Hai-Bo Shao, Jian-Ming Wang, Xiao-Yan Wang, Yi Zheng, Jian-Qing Zhang

Journal of Electrochemistry

The feasibility of employing aluminum in KOH ethanol solution as a battery anode system was discussed. Weight loss measurement showed that the corrosion rate of Al is low enough to be used in sealed batteries. Through the measurements done by anodic polarization, EIS and galvanostatic discharge, it was found that A1 is electrochemical active in a wide potential range in this system, and its discharge mechanism is similar to that of A1 in aqueous solution. The discharge potential increased rapidly after a period of time, which might be caused by the discharge products depositing on the electrode surface.

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Preparation And Electrochemical Magnesium Insertion Behaviors Of Mgv_2o_6, Hua-Tang Yuan, Li-Fang Jiao, Jian-Sheng Cao, Xiu-Sheng Liu, Ming Zhao, Yong-Mei Wang Nov 2004

Preparation And Electrochemical Magnesium Insertion Behaviors Of Mgv_2o_6, Hua-Tang Yuan, Li-Fang Jiao, Jian-Sheng Cao, Xiu-Sheng Liu, Ming Zhao, Yong-Mei Wang

Journal of Electrochemistry

MgV_2O_6was synthesized by conventional solid-state reaction from MgO and V_2O_(5)as starting materials. X-Ray diffraction analysis showed that the prepared sample belongs to the monoclinic structure. Electrochemical magnesium insertion from aprotic electrolytes such as organomagnesium halides into this host was found possible and exhibited charge/discharge circulation.

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Studies On The Electrochemical Preparation And Electrochemical Properties Of Conducting Polymers——Brief Introduction To The Research Work Of Electrochemistry Of Conducting Polymers In Cas Key Laboratory Of Organic Solids(I), Yong-Fange Academy Of Sciences Li Nov 2004

Studies On The Electrochemical Preparation And Electrochemical Properties Of Conducting Polymers——Brief Introduction To The Research Work Of Electrochemistry Of Conducting Polymers In Cas Key Laboratory Of Organic Solids(I), Yong-Fange Academy Of Sciences Li

Journal of Electrochemistry

Conducting polymers have drawn much attention since the discovery of conducting polyacetylene in 1977, due to the novelty and curiosity of their structure and properties as well as their promising applications in many aspects. Among the studies of conducting polymers, the electrochemical preparation and electrochemical properties of conducting polymers are of special importance, because the electropolymerization is a main method for preparing conducting polymer films and the electrochemical properties are the basis for their applications in the fields of electrode materials for batteries, electrocatalysis, electrochromic display, etc. We are one of the earliest research groups in the world to perform …

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Electrochemical Behavior Of Aluminized Steel In Seawater Environment, Cheng-Hao Liang Nov 2004

Electrochemical Behavior Of Aluminized Steel In Seawater Environment, Cheng-Hao Liang

Journal of Electrochemistry

The electrochemical behavior of aluminized steel in seawater has been studied by immersion test and electrochemical technology. The results indicate that compared with 20# steel, the aluminized steel has lower corrosion potential and stronger anodic activity in seawater. Its anodic solution will occur at low potential. The immersion test shows that the corrosion rates of aluminized steel and 20# steel are 5.80 mg/dm~2 dand 3.36 mg/dm~2 d, respectively. Through the X-ray diffraction patternanalysis, it was found that chloride ions exit in the corrosion products of aluminized steel. It proves the participation of chloride ions in the process of corrosion, which …

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The Inhibition Synergistic Effect Between Imidazoline Derivative And Thiourea, Jing-Mao Zhao, He-Xia Liu, Wei Di, Yu Zuo Nov 2004

The Inhibition Synergistic Effect Between Imidazoline Derivative And Thiourea, Jing-Mao Zhao, He-Xia Liu, Wei Di, Yu Zuo

Journal of Electrochemistry

The inhibition synergistic effect between imidazoline and thiourea for carbon steel in CO_2 saturated brine solution was investigated by using weight-loss method, polarization curves measureament and XPS. The results showd that the inhibition efficiency increased significantly when imidazoline derivative was added as a corrosion inhibitor in the solution together with thiourea. The N and S atoms in the inhibitor film adsorbed on the surface of carbon steel, and N atoms predominated in the film near the solution and decreased gradually with the film depth and finally S atoms were the major element in the film near the matrix. It was …

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Preparation And Photo-Catalyst Properties Of The Α-Fe_2o_3-Tio_2 Films On Sodium Alginate Polymer, Li-Qin Chen, Huai-Zhen Zhong, Ri-Yao Chen, Xi Zheng, Zhen Chen Nov 2004

Preparation And Photo-Catalyst Properties Of The Α-Fe_2o_3-Tio_2 Films On Sodium Alginate Polymer, Li-Qin Chen, Huai-Zhen Zhong, Ri-Yao Chen, Xi Zheng, Zhen Chen

Journal of Electrochemistry

Three new nano thin films of α-Fe_2O_(3)、TiO_2 and α-Fe_2O_(3)-TiO_2 by doping their powder with sodium alginate polymer were prepared. Surface structure and catalytic activities of the films were characterized by FTIR、XRD、PL、TEM and I-V techniques. The results of UV-visible absorption showed that the methylene blue was mineralized in aqueous of α-Fe_2O_(3)/SA、TiO_2/SA and (α-(Fe_2O_(3)))-TiO_2 /SA upon radiation with ultra violet light. α-Fe_2O_(3) enhanced their photo-decolorized-activities by doping 15% TiO_2.

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Applications Of New Activated Carbon Meterials In The Electric Double-Layer Capacitor, Jian-Jun Zhang Nov 2004

Applications Of New Activated Carbon Meterials In The Electric Double-Layer Capacitor, Jian-Jun Zhang

Journal of Electrochemistry

A new type activated carbon whose precursor was coconut shell could be obtained using specific physics-chemistry activation, and the activated carbon was applied as the material of electrode in EDLC(electrical double-layer capacitor),which had a large specific capacitance,and could charge and discharged in some large currents. Carbon dioxide and acid were used to modify carbon,and the effects of post-treatment on surface area and pore volume were investigated. A moulding method which has influence on some properties of carbon electrode with PTFE additive was researched in the paper.

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Improvement And Its Mechanism Of Storage Performance Of Ni-Mh Battery, Xiao-Feng Li Nov 2004

Improvement And Its Mechanism Of Storage Performance Of Ni-Mh Battery, Xiao-Feng Li

Journal of Electrochemistry

The storage performance of nickel-metal-hydride (Ni-MH) battery was studied by using galvanostatic charge-discharge and cyclic voltammetry. The experimental results indicated that CoOOH could not be completely restored after its being thoroughly reduced at lower potential, which might weaken electric conduction network in the positive electrode and result in fading of electrochemical properties of Ni-MH battery. Addition of nickel powder as a conductive agent into the positive electrode was beneficial to the capacity recovery after storage.

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Effect Of Fe~(3+) Dopen Of Titanium Dioxide Film On Absorption Spectra And Photo Catalysis, Mei-Qun Xiao, Jia-Nian Shen, Moucheng Li, Peng-Fei Wu, Dong Liu, Yu-Juan Zhang Nov 2004

Effect Of Fe~(3+) Dopen Of Titanium Dioxide Film On Absorption Spectra And Photo Catalysis, Mei-Qun Xiao, Jia-Nian Shen, Moucheng Li, Peng-Fei Wu, Dong Liu, Yu-Juan Zhang

Journal of Electrochemistry

Photo-catalytic titanium dioxide film in nano crystalline has been prepared by electrochemical oxidation process and adding different amount of ferric ion into the electrolyte during the anodic oxidation.The effects of Fe~(3+) dopen on absorption spectra and photo-catalytic of the titanium dioxide films have been studied. It shows that the Fe~(3+) dopen caused the red shife of the absorption edge for the incoming light and exhibited the improved photocatalytic reactivity.

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Study On Mass Transport In Liquid Layer Adjacent To The Electrode Through Transmission Vop-Spectroellipsometry, Wei Zhu, Yangyu-Ru Yangyu-Ru, Zong-Qing Huang Nov 2004

Study On Mass Transport In Liquid Layer Adjacent To The Electrode Through Transmission Vop-Spectroellipsometry, Wei Zhu, Yangyu-Ru Yangyu-Ru, Zong-Qing Huang

Journal of Electrochemistry

In electrochemical system, the mass transport process in liquid layer adjacent to electrode is studied through theoretical analysis only.The diffusion process can be analyzed theoretically by Fick's law for homogeneous media. Up to now, none of satisfied experimental method has been reported for studying mass transport of a whole process in liquid media yet. This paper described the experimental approach to explore mass transport in electrochemical system by transmission Vop-spectroellipsometry briefly.

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The Investigation Of Bafesi/C Alloy Composite As Anode Materials For Li-Ion Battery, Rui-Xiang Feng, Hua Dong, Xin-Ping Ai, Han-Xi Yang Nov 2004

The Investigation Of Bafesi/C Alloy Composite As Anode Materials For Li-Ion Battery, Rui-Xiang Feng, Hua Dong, Xin-Ping Ai, Han-Xi Yang

Journal of Electrochemistry

A novel BaFeSi/C composite was prepared by mechanical ball milling, and lithium insertion reactions on the composite electrode were investigated by cyclic voltammetry ,charge-discharge measurements, XRD and XPS spectroscopy. It is demonstrated that the capacity retention with indiscernible capacity decas during charge-discharge cycling. The improved cycling ability of the composite is suggested from a cooperative action by inactive FeSi_(2 )and BaSi_2 matrix and outer graphite shell, which both buffer the volumetric changes of the active Si phase and provide a good connection for electronic and ionic conduction during lithium insertion and extraction processes.

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Lico_(X)Ni_(1-X)O_2 Cathode Materials Prepared By Electrolysis Of Co And Ni, Jin-Ping Wei, Xin Sun, Xiao-Yu Wang, Xi-Kui Bian, Jin-Ling Zhai, Yan-Jie Yan-Jie Nov 2004

Lico_(X)Ni_(1-X)O_2 Cathode Materials Prepared By Electrolysis Of Co And Ni, Jin-Ping Wei, Xin Sun, Xiao-Yu Wang, Xi-Kui Bian, Jin-Ling Zhai, Yan-Jie Yan-Jie

Journal of Electrochemistry

A new electrolytic method was developed to prepare LiCo_(x)Ni_(1-x)O_2 as a cathode material of lithium-ion battery. Contrary to the traditional method, electrolytic method is a potential method with simple process to industrialization and no pollution. Metal cobalt and nickel were electrolysed in parallel to prepare the precursor of Co_( x )Ni_(1- x )(OH)_2.Different compositional precursors could be conveniently prepared by changing electrolytic current. The LiCo_(0.3)Ni_(0.7)O_2 cathode prepared by this method was found favorable charge-discharge and cycle properties. For the LiCo_(0.3)Ni_(0.7)O_(2 )cathode material, the discharge capacities in the 1st and 50th cycles were 163 mAh/g and 140 mAh/g with charge retention …

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The Electrochemical Performance Of Modified Spinel At Elevated Temperature, Zhen-Ping Cai, Xiao-Hong Chen, Shi-Gang Lu, Ming-Xun Li, Wei-Hua Jin Nov 2004

The Electrochemical Performance Of Modified Spinel At Elevated Temperature, Zhen-Ping Cai, Xiao-Hong Chen, Shi-Gang Lu, Ming-Xun Li, Wei-Hua Jin

Journal of Electrochemistry

The modified LiMn_2O_4 cathode materials for lithium ion batteries have been synthesized by solid-state reaction. The crystal structure and electrochemical performance of products have been investigated by SEM、XRD and electrochemical measurements. The XRD analysis indicated that all the synthesized products possess Fd3m spinel LiMn_2O_4 structure. Those modified LiMn_2O_4 materials showed improved cycling capacity over pure spinels at high temperature and room temperature.

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Synthesis And Electrochemical Behavior Of Layered-Structure Limn_(1-X)Cr_Xo_2, Jie Xiao, Hui Zhan, Yun-Hong Zhou Aug 2004

Synthesis And Electrochemical Behavior Of Layered-Structure Limn_(1-X)Cr_Xo_2, Jie Xiao, Hui Zhan, Yun-Hong Zhou

Journal of Electrochemistry

The Layered-structure LiMn_(1-x)Cr_xO_(2 )(x=0,0.15) solid solution has been prepared by the rheological phase method. From the XRD results, undoped LiMnO_(2) crystallized almost entirely in the orthorhombic phase while the structure of LiMn_(0.85)Cr_(0.15)O_(2) belongs to monoclinic phase. TEM investigation shows that the final powder product consists of ultrafine spherical particles which are distributed homogeneously, with the average diameter ranging from 60 to 300nm. The initial discharge capacity of LiMn_(0.85)Cr_(0.15)O_(2) is much higher than that of undoped LiMnO_(2). After 40 cycles, the capacity retention for m-LiMn_(0.85)Cr_(0.15)O_(2 )is 94% at the current rate of 50mA/g under room temperature. The results of electrochemistry tests …

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Adual-Celltechnique And Its Application In Electrocatalytic Study Of Pt-Ru Metals, Lei Su, Bing-Liang Wu Aug 2004

Adual-Celltechnique And Its Application In Electrocatalytic Study Of Pt-Ru Metals, Lei Su, Bing-Liang Wu

Journal of Electrochemistry

Two local electrochemical reactive interfaces are established using two strips of Nafion~ membrane separated each other, which are in contact with different surface regions of the same metal-sheet working electrode. One potentiostatis used to control thepotentialof one electrochemical reactive interface to generate adsorbed surface speciesand the other potentiostatto hold the potential of the second interface as a detector of the intermediate. The adsorbed surface species driven by the difference in surface concentration diffuses alongthe surface of the metal-sheet between both local electrochemical interfaces and can be detected at the second interface when they achieveover there.The surface diffusion coefficient of the …

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Nucleation And Crystal Growth Of Pt Electrodeposition On Poly Crystal Au Microdisc Electrode, Zhi-Yong Tao, Pei-Fang Liu Aug 2004

Nucleation And Crystal Growth Of Pt Electrodeposition On Poly Crystal Au Microdisc Electrode, Zhi-Yong Tao, Pei-Fang Liu

Journal of Electrochemistry

Based on the Fleischmann's model of nucleation and crystal growth for electrodeposition combined with the Barradas-Bosco's adsorption-nucleation model for electrochemical phase formation, the chronoamperometry was well fitted for Pt deposition on polycrystalline Au micro disc electrodes (30 μm in diameter) in different H_(2)PtCl_(6) concentrations at different over-potentials. The initial stage of Pt deposition in dilute H_(2)PtCl_(6) could be interpreted by the model of H_(2)PtCl_(6 ) adsorption combined with instantaneous nucleation and two-dimensional cylindrical growth. The rate constant of the two-dimensional growth increased linearly with overpotential. Then the deposit grew layer by layer and the rate constant increased non-linearly with overpotential. …

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Electrochemical Reduction Of Nitrobenzene On The Wc Electrode In Acidic Solution, Chun-An Ma Aug 2004

Electrochemical Reduction Of Nitrobenzene On The Wc Electrode In Acidic Solution, Chun-An Ma

Journal of Electrochemistry

The tungsten carbide (WC) electrode was constructed by using polyterafluoroethylene as binder. The electrochemical behavior of nitrobenzene on the WC electrode in acidic solution was investigated by cyclic voltammetry, linear scan method and chronoamperometry. Experimental results showed that WC electrode had good activity for the electrochemical reduction of nitrobenzene, and the electrode process was controlled by diffusion and electrochemical stepssimultaneously. The apparent active energy of the electrode process is 23.7kJ mol~(-1), while the active energy of the electrochemicalstep is 10.91kJ mol~(-1).

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Preparation And Electrochemical Performance Of New Composite Seperators For Lithium-Ion Batteries, Hu Cheng, Hong-Yan Du, Yong Yang Aug 2004

Preparation And Electrochemical Performance Of New Composite Seperators For Lithium-Ion Batteries, Hu Cheng, Hong-Yan Du, Yong Yang

Journal of Electrochemistry

New composite seperators for lithium ion batteries were prepared by coating PEO mixed with nanosize SiO_(2)onto microporous polypropylene(PP) seperators. Highly conductive electrolytes were prepared by soaking them in an electrolyte solution. With these composite separators, the lithium ion cell consisting of Li anode and LiNi_(0.8)Co_(0.2)O_(2)cathode were assembled. The high initial discharge capacity and good capacity retention were obtained through the cell.

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Synthesis Of (S)-3-Phenylpropane-2-Tert-Butoxycarbonylamino- 1-Thiol And Its Electrochemical Behavior Self-Assembled On Gold, Sun Ru Aug 2004

Synthesis Of (S)-3-Phenylpropane-2-Tert-Butoxycarbonylamino- 1-Thiol And Its Electrochemical Behavior Self-Assembled On Gold, Sun Ru

Journal of Electrochemistry

The synthesis of (S)-3-Phenylpropane-2-tert-butoxycarbonylamino- 1-thiol(N-Boc-APT) from L-phenylalanine was reported. L-Phenylalanine was reduced to the corresponding amino alcohol, protection of the amino group using tert-butyl pyrocarbonate gave (S)-2-tert-butoxycarbonylamino-3-phenylpropane-1-ol, which was then O-mesylated and treated with potassium thioacetate in DMF to give 3-phenylpropane-2-tert- butoxycarbonylamino-1-etylmercapto. After the acetyl group was removed with ammonia in alcohol, the desired target molecular was obtained. The structure of intermediate and target molecular was conformed by IR and ~(1)HNMR. We made N-Boc-APT self-assemble-modificated gold electrode and investigated its electrochemical behavior. The CV results of methylene blue on nano-Au/N-Boc-APT SAM/Au electrode showed that nano-Au could speed this electron transfer …

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Effects Of Barium On The Performance Of Secondary Alkaline Zinc Electrode, Yi Zheng, Jian-Ming Wang Aug 2004

Effects Of Barium On The Performance Of Secondary Alkaline Zinc Electrode, Yi Zheng, Jian-Ming Wang

Journal of Electrochemistry

The active material of secondary alkaline zinc electrode with barium additives was prepared by a chemical reaction method and characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The electrochemical performance of various pasted Zn electrodes was investigated by cyclic voltammetry, charge/discharge method and electrochemical impedance spectra (EIS) technology. The addition of barium can synthesize a compound barium zincate with the molecular structure of BaZn(OH)_(4)· xH_(2)O and improve the discharge performance. The EIS of the various Zn electrodes showed two time constants besides diffusion impedance, including a state variable representing the covering degree of discharge products on the electrode …

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Lithium Insertion Into Tio_2(B) Nanobelts Synthesized By The "Soft Chemical" Method, Cha-Geng Nie, Zheng-Liang Gong, Lan Sun, Juan Zuo, Yue-Kun Lai, Chang-Jian Lin Aug 2004

Lithium Insertion Into Tio_2(B) Nanobelts Synthesized By The "Soft Chemical" Method, Cha-Geng Nie, Zheng-Liang Gong, Lan Sun, Juan Zuo, Yue-Kun Lai, Chang-Jian Lin

Journal of Electrochemistry

TiO_(2)(B) Nanobelts were synthesized by using the "Soft chemical"method. The products were characterized by means of transmission electron microscope(TEM), X-ray diffraction(XRD), Raman spectrum and energy dispersive spectrum(EDS). Galvanostatic charging and discharging tests showed that lithium-ion intercalation/deintercalation occurred reversibly in the TiO_(2)(B) nanobelts electrode, and a high capacity (265 mAh·g~(-1)) can be obtained. The results suggested that TiO_(2)(B) Nanobelts might be a promising negative electrode material of second Lithium battery.

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Preliminary Study Of Speek Membranes For Direct Methanol Fuel Cells Application, Su-Zhen Ren Aug 2004

Preliminary Study Of Speek Membranes For Direct Methanol Fuel Cells Application, Su-Zhen Ren

Journal of Electrochemistry

This paper describes the methanol permeability characterization of SPEEK membranes and their feasibility for DMFC application. The SPEEK membranes showed a significant lower methanol permeation than Nafion~115 determined from voltammetric methods. An increase in open circuit voltage was found in the performance of SPEEK membranes in DMFC. The power density of the cell using SPEEK membrane was considerably poorer than that of Nafion~115. If modified properly, the SPEEK membranes can be chosen for DMFC application based on this study.

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The Effect Of Ferrous Sulphate On The Electroless Depositionof Co-Fe-P Alloys, Sen-Lin Wang, Qing-Hua Li Aug 2004

The Effect Of Ferrous Sulphate On The Electroless Depositionof Co-Fe-P Alloys, Sen-Lin Wang, Qing-Hua Li

Journal of Electrochemistry

Electroless deposition of Co-P alloy and Co-Fe-P alloy from an alkaline bath, containing sodium hypophosphite as a reducer, boric acid as a buffer agent and sodium citrate as a complexing agent, was investigated respectively. The effects of process parameters, such as pH of solution and metallic salt mole ratio of CoSO_(4)/FeSO_(4), on the plating rate were examined. It was found that the presence of ferrous sulfate in the bath has an inhibitory effect on the alloy deposition. As a consequence, the plating rate of Co-Fe-P is lower than that of Co-P. The electrochemical polarization measurements have been carried out to …

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Study On The Electrochemical Behaviors Of Prussian Blue Film Using Electrochemical Quartz Crystal Microbalance, Hui Liao, Xia-Qin Wu, Zong-Rang Zhang Aug 2004

Study On The Electrochemical Behaviors Of Prussian Blue Film Using Electrochemical Quartz Crystal Microbalance, Hui Liao, Xia-Qin Wu, Zong-Rang Zhang

Journal of Electrochemistry

Prussian blue (PB) films were electrodeposited on the Pt/QCMelectrodes in the solutions with or without Phenanthroline by cyclic voltammetry. The frequencyshift during electrodeposition wasmeasured,and the EQCM behaviors of these two types of PB films in potassium chloridewere also studied. Results show that electrodeposition process of PB film in the solution with phenanthroline wasdifferent from that in the solution without phenanthroline. The PB film modified Pt/QCMelectrodeprepared in the solution with phenanthroline shown an excellent electrocatalytic activity for the reduction process of hydrogen peroxide.

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Chemical Microetching Of Three-Dimensional Gear-Like Pattern On Nickel Surface, Zhu-Fang Liu Aug 2004

Chemical Microetching Of Three-Dimensional Gear-Like Pattern On Nickel Surface, Zhu-Fang Liu

Journal of Electrochemistry

The chemical micromachining on nickel surface with three-dimensional (3D) gear-like mold was realized by confined etchant layer technique (CELT). By using effective chemical etching and scavenging system (HNO_(3) + NaOH) and optimizing experimental parameters, such as the etching time, etching current density, concentration of the etchant or and scavenger, we obtained the etched pattern, which is close to negative copy of the mold. The etched micro-pattern characterized by SEM and AFM, demonstrates that CELT can be applied to the 3-D microstructure replication on nickel surface .

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The Electrochemical Behavior And Determination Of Gsh At The Powder Microelectrode, Jian Chen, Zhong-Yu He, Chuansin Cha, Huan Liu Aug 2004

The Electrochemical Behavior And Determination Of Gsh At The Powder Microelectrode, Jian Chen, Zhong-Yu He, Chuansin Cha, Huan Liu

Journal of Electrochemistry

In this paper, the electrochemical behavior of GSH at the surface of platinum(Pt) electrode, glass carbon(GC) electrode and acetylene black packed powder microelectrode (AB-PME) was studied. It was found that the electrochemical oxidations of GSH at both Pt and GC electrode were highly irreversible. No current peak or current plateau could be observed from the CV curves. The direct electro-oxidation of GSH at carbon surface was achieved by using the PME technique.In this case, the apparent reversibility of GSH oxidation was enhanced significatly .The overpotential of GSH oxidation was reduced to 0.5 V at the surface of AB-PME compared with …

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