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Chinese Chemical Society | Xiamen University

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Full-Text Articles in Chemical Engineering

Electrocatalytic Reduction Of Nitrite In The Presence Of Complex Of Cobalt(Ⅱ) And 1,10 Phenanthroline, Jian Tong, Xiaojun Dang, Hulin Li May 1996

Electrocatalytic Reduction Of Nitrite In The Presence Of Complex Of Cobalt(Ⅱ) And 1,10 Phenanthroline, Jian Tong, Xiaojun Dang, Hulin Li

Journal of Electrochemistry

The electrochemistry of cobalt(Ⅱ) 1,10 phenanthroline Co(Phen) 2+ 2 complex and its ability to electrocatalyze the reduction of nitrite were studied , we found that this complex could act as a catalyst in alkaline or neutral solution for nitrite reduction. We have investigated the effect of the complex composition on electrocatalytic ability. The effects of pH value, complex concentration, regeneration and activation of electrocatalyst on the catalytic current have been studied and discussed.

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Electrocatalytic Oxidation Of Some C 2 Compounds(Alcohols, Aldehydes, And Carboxylic Acids) On A Pt/Sb Ad Electrode, Hong Li, Lincai Jiang, Xiong Jiang May 1996

Electrocatalytic Oxidation Of Some C 2 Compounds(Alcohols, Aldehydes, And Carboxylic Acids) On A Pt/Sb Ad Electrode, Hong Li, Lincai Jiang, Xiong Jiang

Journal of Electrochemistry

The electrocatalytic oxidation behavior of some C 2 compounds(alcohols, aldehydes and carboxylic acids) on a Pt/Sb ad electrode prepared in situ or ex situ UPD was investigated using pontential sweep and rotating disc electrode methods. It is confirmed that Pt/Sb ad electrode show the most electrocatalytical active to the oxidation of aldehyde functional group and only a little activity to the oxidation of hydroxyl group, but no activity for the oxidation of carboxyl group. The experimental results show that the activity of the Pt/Sb ad electrode prepared by ex situ UPD is higher than that prepared by in situ UPD. …

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An Indirect Electrochemical Oxidation Of Toluene─Catalytic Effects Of Ag(Ⅰ) On Mn(Ⅱ)/Mn(Ⅲ) Couple Transition At Pt Electrode, Zhonghua Wang, Yunan Qu, Xingguo Yan, Qngmin Hua, Guacai Chen, Zhongquan Wang Feb 1996

An Indirect Electrochemical Oxidation Of Toluene─Catalytic Effects Of Ag(Ⅰ) On Mn(Ⅱ)/Mn(Ⅲ) Couple Transition At Pt Electrode, Zhonghua Wang, Yunan Qu, Xingguo Yan, Qngmin Hua, Guacai Chen, Zhongquan Wang

Journal of Electrochemistry

The Catalytic effects of Ag(Ⅰ) on toluene oxidation by Mn(Ⅲ) as well as the anodic generation of Mn(Ⅲ) were investigated. The rates of toluene oxidation were first order with respect to both Ag(Ⅰ) and Mn(Ⅲ). Ag(Ⅱ) formed on the surface of the platinum anode when Ag(Ⅰ) was present in the anolyte, which catalyic the Mn(Ⅱ) to Mn(Ⅲ) in solution.

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Research On Molten Carbnate Fuel Cell, Naichao Li, Baolian Yi, Lianying Kong, Enjun Zhang, Huaxin Lin, Tianxi Qu, Yingcai Cheng Feb 1996

Research On Molten Carbnate Fuel Cell, Naichao Li, Baolian Yi, Lianying Kong, Enjun Zhang, Huaxin Lin, Tianxi Qu, Yingcai Cheng

Journal of Electrochemistry

Cold-roll-milling has been evaluated as a technique for preparing porous LiAlO_2 matrices for use as a molten carbonate fuel cell electrolyte matrix. This technique produces reliable electrolyte structures with the following characteristics and advantages: ease of handling, uniform thickness, using nontoxic inorganic solvents, controlled pore size distribution, and ability to be impregnated with the alkali carbonate without fracrure.The Molren Carbnatod Fuel Cell(MCFC) was assembled from sintered Ni electrodes and LiAlO_2 electrolyte matrix, the electrode area is 28 cm￣2, the effect of operating conditions on cell performance was tested, it was found that the cell performance changed little with many times …

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Study Of The Modified Electrolytic Manganese Dioxide, Guohui Yuan, Dewei Chu, Rihui Shen, Hongwei Pan, Cuifen Zhang Nov 1995

Study Of The Modified Electrolytic Manganese Dioxide, Guohui Yuan, Dewei Chu, Rihui Shen, Hongwei Pan, Cuifen Zhang

Journal of Electrochemistry

A modified electrolytic manganese dioside doped with Bi(Bi-EMD)wasprepared and examined by XRD and XPS.It is predominantly γ-mnO_2 and the Bi exists as Bi_2O_3 inthe modified material.The content of Bi in Bi-EMDs increased with the increasement of Bi￣(3+)concentration in electrolyte,and reached14.3(wt)% from the bath of 0.008 mol·1￣(-1)Bi￣(3+)+ used.Some Zn /Bi-EMD prototype batteries of AA size were assembled,and which cycle life tests showedthat the Bi-EMD has better reversibility.

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Catalytic Oxidation Of Methanol On Pt/C-Spe And Ptru/C-Spe Electodes, Aihua Su, Changzhi Li, Gongquan Sun, Ying Zhang, Tianhong Lu Nov 1995

Catalytic Oxidation Of Methanol On Pt/C-Spe And Ptru/C-Spe Electodes, Aihua Su, Changzhi Li, Gongquan Sun, Ying Zhang, Tianhong Lu

Journal of Electrochemistry

Anode catalysts of methanol oxidation for direct methanol fuel cell, pt/C andPtRu/C,were prepared by chemical reduction in this work.The results indicated that the PtRu/Cshowed higher electrocatalytic activity than that of Pt/C. It was explained by XRD and XPS analysesthat the existence of Ru enhanced the catalytic activity for electrochemical oxidation of methanol.

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Influence Of O-Phenylenediamine On The Catalysis At Hrp Enzyme Electrode In L,4-Dioxane, Hong Chen, Hui-Huang Wu Nov 1995

Influence Of O-Phenylenediamine On The Catalysis At Hrp Enzyme Electrode In L,4-Dioxane, Hong Chen, Hui-Huang Wu

Journal of Electrochemistry

Horseradish peroxidase(HRP)was immobilized by crosslinkage on the glassycarbon electrode to prepare the enzyme electrede ,where the reduction of H_2O_2 was studied in l,4-dioxane media. It was shown that HRP electrode can catalyze the reduction of H_2O_2 without anymedintor,however, as an activator,o-phenylenediamine can promote the bio-catalysis. In thepresence of the activator,the parallel reactions occurred on the enzyme electrode. The workingcondition of the HRP electrede was investigated as the sensors for H_2O_2 and o-phenylenediamine,alsothe influence of water content in organic phase was discussed on the performance of the enzymeelectrode in organic phase.

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Studies On The Structure Of Licoo_2 Synthesized With Tartaric Acid And The Behaviorof Its Rechargeable Lithium Battery, Fuping Zhang Aug 1995

Studies On The Structure Of Licoo_2 Synthesized With Tartaric Acid And The Behaviorof Its Rechargeable Lithium Battery, Fuping Zhang

Journal of Electrochemistry

The structure of LiCoO_2 synthesized with tartaric acid and the behavior of itsrechargeable Lithium battery have been studied by XRD, XPS, CV. CT. It has been shown thatLiCoO_2 has a space group R3m with hexagonal parameters a=0.281 0 nm,c=1.408 8 nm. Low-spin state Co￣(3+) configuration in LiCoO_2 has been suggested. Also,Li_2O, was identified onits surface.Furthermore, the capacity and the middle working voltage of its Lithium battery are about 120 mA·h·g￣(-1) and 3.8 V,respectively.The EMF of the cell changes with the Lithium composition of itscathode following E=4.318-0.450 X￣(2/3) in 0.451≤X≤0.934.

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The Oxidation Of Hydrogen Absotbing Alloys And Its Inhibition, Suqin Wang, Baojia Xia, Geping Yin, Pengfei Shi Aug 1995

The Oxidation Of Hydrogen Absotbing Alloys And Its Inhibition, Suqin Wang, Baojia Xia, Geping Yin, Pengfei Shi

Journal of Electrochemistry

This paper introduces the method to judge:1)the possibility of oxidation of themetal hydride electrode in an anode process by cyclic voltammetric curves,2)the oxidation pattern ofmetal hydride electrode in oxygen atmosphere in various charged states,and 3)the inhibition ofoxidation of hydrogen absorbing alloys by certain surface treatment.

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The Reduction Of Oxygen To Hydrogen Peroxide At The Poly(O-Phenylenediamine)-Filmed Electrode, Zhaoe Lu, Tiangeng Zhong, Guanyong Zhang May 1995

The Reduction Of Oxygen To Hydrogen Peroxide At The Poly(O-Phenylenediamine)-Filmed Electrode, Zhaoe Lu, Tiangeng Zhong, Guanyong Zhang

Journal of Electrochemistry

The poly(o-phenylenediamine)(PPD)filmed graphite electrode was formed byelectro-polymerization of o-phenylenediamine in acidified(pH=1)0.2 mol·L-1 Na_2SO_4 solutionusing the cyclic voltammetric methed. The catalytic effect of the electrcareduction of oxygen in acidsolution was demonstrated by the voltammogram of the electrede in the oxygen saturated acid solutionof Na_2SO_4. The current efficiency of the reduction of oxygen to hydrogen peroxide was determined byIhe electrolysis in a divided cell under the condition of constant current. The various effectsinfluencing the accm ulation of H_2O_2 in the catholyte were discussed.

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Studies On Coordination Behavior Of Dimethyl Sulfoxide In Complex Of Rare Earth With Cryptand, Shichang Liu May 1995

Studies On Coordination Behavior Of Dimethyl Sulfoxide In Complex Of Rare Earth With Cryptand, Shichang Liu

Journal of Electrochemistry

lectrochemical reduction reaction in the course of the titration of Eu ( 2.2.2)and Eu( 2.2)using strong bonding solvent,DMSO,in C_2H_4Cl_2 has been investigated by cyclicvoltammetry. The greater the concen tration of strong bonding solvent,the more negative the half-wave potentials for the reduction reaction are. The coordination number of Eu(2.2.2 ) and Eu(2.2)which are 2 and 3 respectively,with DMSO can be calculated,according to the relations betweenhalf -wave potentials and the variety of concentration of DMSO.

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Photoelectrochemical And Spectroelectrochemical Studies Oniron Oxide Ultrafine Particles, Maizhi Yang, Yongjun Ji, Wen Zhang, Shengmin Cai May 1995

Photoelectrochemical And Spectroelectrochemical Studies Oniron Oxide Ultrafine Particles, Maizhi Yang, Yongjun Ji, Wen Zhang, Shengmin Cai

Journal of Electrochemistry

in this paper, Raman spectra, photocurrent and the UV-VIS reflectance aremeasured for studying the α-Fe_2O_3ultrafine particles adsorbed on Pt electrode. The blue shifts ofRaman peaks demonstrate the size quantization effect for the particles of 50 nm in diameter ascompared with the bulk material. With the changing of the potential , the photocurrent decrcases as theUV-VIS reflectance increases, and vice-versa. Therefore, the potential not only affects the hargetransfer direcdtion in the interface of electrede/redox couple, but also influences the light absortion onthe surface of particles.According to the results of photoelectrochemistry, we suggest that the cathedicphotocurrent in the potential range of more …

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The Electrochemical Reduction Of 2-Ethylanthraquinone(2eaq), Yaobin Zhu May 1995

The Electrochemical Reduction Of 2-Ethylanthraquinone(2eaq), Yaobin Zhu

Journal of Electrochemistry

The process of electrochemical reduction of 2EAQ in DMSO is studied using CVand ESR methods in this work, Pt, Pd and some implanted materials are used as electrodes. Thequasi-rever+sible property of two electron transfer steps and their following homogeneous chemicalreactions are illustrated,The mechanism of the electrochemical red uction of 2 EAQ and the kineticparameters of the related steps are obtained. Having measured the influence of water content in thesystem, the effect of the proton donor is discussed. After comparising the experimental results witheach other these experiments gives us the idea that the replacement of metal Pd or some Pd-catalystswith pd-implanted …

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Horseradish Peroxidase/Poly-O- Phen Ylenediamine Mem Brane Electrode:Preparation And Properties, Dong Wei, Huihuang Wu May 1995

Horseradish Peroxidase/Poly-O- Phen Ylenediamine Mem Brane Electrode:Preparation And Properties, Dong Wei, Huihuang Wu

Journal of Electrochemistry

A horseradish peroxidase(HRP)/poly-o-phenylenediamine(PPD)membraneelectrede was prepared by electropolymerization of o-phenylenediamine on glassy carbon in pH 7.0phosphate buffer,the process of the enzyme immobilization was studied,The enzyme electredeobtained exhibits the activity to catalyze the electrored uction of hydrogen peroxide in the absence ofany electron transfer mediator.The red uction reaction occurs in the potential range of PPD redoxprocess,it was believed that the polymer participates in electron transfer of the enzyme.The enzymereaction kinetics at rotating H RP/PPD electrede was analysed,and the factors influencing kineticparameters were discussed.

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An Indirect Electrochemical Oxidation Of Toluene──Anodic Oxidation Of Mn(Ⅱ) On The Lead Electrode, Zhonghua Wang, Qingmin Hua, Guaeai Chen May 1995

An Indirect Electrochemical Oxidation Of Toluene──Anodic Oxidation Of Mn(Ⅱ) On The Lead Electrode, Zhonghua Wang, Qingmin Hua, Guaeai Chen

Journal of Electrochemistry

The electrochemical oxidation of Mn (Ⅱ) to Mn(Ⅱ) in concentrated H_2SO_4(2￣8 mol . L-1) at lead electrede has been studied. It is found that the electrede surface is oxidized toPbO_2 in a direct electrochemical reaction, then PbO_2formed reacts with Mn (Ⅱ) in a chemicalreaction. Some effects involves current density , concentration of H_2SO_4 , temperature and conversionwere evaluated. The rule of electrogenerated Mn (Ⅲ) in flow electrolysis cell were determined atseveral conditions. The current efficiency at greater than 90% is obtained in general.

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Electroreduction Of The Nittobenzene On Titanium Electrode Implanted With Palladium, Zhongda Wu, Xianjun Zhu, Hongsen Wang Feb 1995

Electroreduction Of The Nittobenzene On Titanium Electrode Implanted With Palladium, Zhongda Wu, Xianjun Zhu, Hongsen Wang

Journal of Electrochemistry

The titanium substrates were bombarded with 1×10￣(17)～5×10￣(17)ions·cm￣(-2) ofpalladium at the room temperature. The surface composition of implanted electrede and concentration-depth profiles of various elements were measured by AES. The electrored uction processes ofnitrobenzene(NB)in 0.1 mol/L NaOH solution at Pd/Ti electrodes have been investigated by cyclicvoltaivimetry.The results show that the palladium implanted titanium electrodes exhibit a high catalyticactivity in the electroreduction of NB. The NB radical anion,which is the product of one-electronelectroreduction of NB,was detected by ESR in-situ in conjunction with electrochemical methods. Aniline was also detected as a product of electroreduction of NB by using UV-spectra in-situ. According to the …

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Electroreduction Of Holmium Ion On Iron Electrde In Molten Cholorides, Qiqin Yang, Guankun Liu, Yuzhi Su Feb 1995

Electroreduction Of Holmium Ion On Iron Electrde In Molten Cholorides, Qiqin Yang, Guankun Liu, Yuzhi Su

Journal of Electrochemistry

The cyclic voltammetry,open circuit potential-time curve after poteritiostaticelectrolysis,current-time curve at potential step,x-ray diffraction and electron probe microanalysiswere used to investigate the electrode process of Ho(Ⅲ)reduced on iron electrode in molten chloridesand the phases of surface alloy layer.The Ho-Fe alloys are formed at first,and then the metallicholmium is deposited when Ho(Ⅲ)is reduced on iron electrede. The charge transfer is reversible. Thefree energies of formation for the four intermetallic compounds of Ho-Fe system,the diffusioncoefficients and diffusion activation energy of Ho in alloyed cathode are determined.

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Synthesis Of Li_Xcoo_2 And Its Behaviour In Rechargeable Lithium Battery, Mingfeng Guo, Ruimin Yang, Zebo Zhang, Jincao Ye Feb 1995

Synthesis Of Li_Xcoo_2 And Its Behaviour In Rechargeable Lithium Battery, Mingfeng Guo, Ruimin Yang, Zebo Zhang, Jincao Ye

Journal of Electrochemistry

The Variations of crystal lattice parameters of Li_xCoO_2 during charge anddischarge have been st ud ied by XRD and AAR spectroscopy.It was found that the Li_xCoO_2 crystalvolume expanded during charge and contracted during discharge.The crystal lattice structure wasbroken because of the formation of Co_3O_4 when deeply charge.The variation of lattice parameter C_0value in cycling process was similar to that in charge process.The variation of 006 peak was the mostsensitive in every case.In case of preheating for 20 hours at 700℃ before operating hightemperature,the 006 peak obtained an enhancement obviously.It has had the good rechargeability inmeasurement of the cyclic voltammograms,the CV …

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The Study Of The Growth Processes Of The Oxides On Lead Electrodes In Sulfuric Acid Solution, Hesheng Zhai, Xuguang Chen, Jinkua You, Yong Yang, Zugeng Lin Feb 1995

The Study Of The Growth Processes Of The Oxides On Lead Electrodes In Sulfuric Acid Solution, Hesheng Zhai, Xuguang Chen, Jinkua You, Yong Yang, Zugeng Lin

Journal of Electrochemistry

The growth processes of PbO and PbO_2 on lead electrodes have been investigatedby using in-situ methods that are combined with temporary AC resistance measurment technique andin-situ laser scanning photoelectrochemical microscopy.It is found that a linear relationship existsbetween the electrode resistance(R)and￣(1/2) after the electrode is oxidized at +0.6 V(vs.Hg/H_2SO_4/35%H_2SO_4)for more than 5 min.This result suggests that the growth of PbO is well distributedduring the early stage of oxidation.The study by using laser scanning photoelectrochemical microscopyhas further proved this point.The results also show that the growth of PbO_2 takes place and develops.

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A Photoelectrochemical Investigation Of Zirconium Oxide Film, Maizhi Yang Feb 1995

A Photoelectrochemical Investigation Of Zirconium Oxide Film, Maizhi Yang

Journal of Electrochemistry

A photoelectrochemical investigation has been carried out on zirconium initialoxide film and its oxide film grownanodically at constant rate up to different thickness. Both anodicand cathedic photocurrents on the photocurrent spectrum depended on the potential,but had littlerelation with the forming anedic films or measuring solutions. Photocurrent spectrum and photocurrenttransients suggested that the oxide films on zirconium were duplex layers structure. The internal layerwas ZrO_2 and the external layer ZrO_2·(H_2O)_n. The photocurrent included photogenerated carrier ininternal and external oxide films,as well as internal photoinjection process for electrons from thesubstrate metal into the electrode/electolyte interface reacting with the redox couple. The analysis …

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Electrocatalytic Oxidation Of Formaidehyde And Formic Acid On A Pt/Sb_(Ad) Electrode, Hong Li, Lincai Jiang, Xiong Jiang Feb 1995

Electrocatalytic Oxidation Of Formaidehyde And Formic Acid On A Pt/Sb_(Ad) Electrode, Hong Li, Lincai Jiang, Xiong Jiang

Journal of Electrochemistry

The electrocatalytic activity for the oxidation of formaldehyde and formic acid ona Sb-modified platinum (Pt/Sb_(ad))was investigated.Results showed that the Pt/Sb_(ad) electrode waselectrocatalytically more active than a Pt electrode in the anodic oxidation of formaldehyde and formicacid.In the case of formaldehyde,an oxidation peak appeared at a potential of ca.0.7V.During theoxidation of formic acid,a 4-fold increase in the 1st peak current was observed.The Sb-modifiedplatinum electrode was found to be most electrocatalytically active at a coverage of 0.75±0.05.Theelectrocatalytic activity of the Pt/Sb_(ad) electrode can be best explained in terms of the geometrical effect,which may lead to the inhibition of the formation of the …

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