Open Access. Powered by Scholars. Published by Universities.®

Chemistry Commons™

Open Access. Powered by Scholars. Published by Universities.®

Cyclic voltammetry

Discipline
Institution
Publication Year
Publication
Publication Type

Articles 91 - 120 of 148

Full-Text Articles in Chemistry

Electrochemical Behavior And Determination Of Paracetamol On Activated Glassy Carbon Electrode, Bao-Yu Tan, Fang Liao, Xiao-Ying He, Qing-Tao Zhu, Jun Hua, Xiao-Li Jiang Nov 2008

Electrochemical Behavior And Determination Of Paracetamol On Activated Glassy Carbon Electrode, Bao-Yu Tan, Fang Liao, Xiao-Ying He, Qing-Tao Zhu, Jun Hua, Xiao-Li Jiang

Journal of Electrochemistry

The electrochemical behavior of paracetamol(PCT) was studied at glassy carbon electrode activated by cyclic voltammetry.In HAc-NaAc buffer solution(pH=4.00),a couple of sensitive redox peaks were recorded about 0.54 V in the cyclic voltammograms.The result indicated that the process was controlled by adsorption and nearly reversible.The reaction electron and proton numbers were estimated,respectively,to be two.Excllent linearity was observed in the correlation between the oxidation peak current and the concentration of PCT in the range of 8.00×10-6～2.00×10-4 mol·L-1.The correlative coefficient was-0.999 18.The detection limit was 6.34×10-6 mol·L-1.This method can be used for the determination of PCT real …

Go to article

Direct Electrochemistry Of Hemoglobin On The Electrode Modified With Ddab And Swcnt, Wen-Jing Hou, Lin Zhou, Xia-Qin Wu, Hong-Xia Zhang, Wen Xie, Liu Yang, Zhong-Qing Lu Aug 2008

Direct Electrochemistry Of Hemoglobin On The Electrode Modified With Ddab And Swcnt, Wen-Jing Hou, Lin Zhou, Xia-Qin Wu, Hong-Xia Zhang, Wen Xie, Liu Yang, Zhong-Qing Lu

Journal of Electrochemistry

Hemoglobin(Hb) was immobilized onto the surface of glassy carbon electrode with the single-wall carbon nanotubes and surfactant didodecyldimethylamonium bromide(DDAB) modified previously and its electrochemical behaviors have been investigated by cyclic voltammetry.A pair of well-defined redox peaks has been obtained.Cyclic voltammetry and electrochemical impedance spectroscopy(EIS) were also used to study on the effect of different concentration of SWCNT in DDAB.The result shows that the 1 mg/mL is the best choice.The dependence of E0' on solution pH with the slope of 39 mV/pH,indicated that redox of the Hb is a one electron reaction with two protons transfer.The results also showed …

Go to article

Design And Fabrication Of The High Efficient Platinum-Nanoporous Gold Catalysts, Zhao-Na Liu, Jin-Tao Zhang, Fang Tian, Peng-Peng Liu, Hou-Yi Ma, Yi Ding Aug 2008

Design And Fabrication Of The High Efficient Platinum-Nanoporous Gold Catalysts, Zhao-Na Liu, Jin-Tao Zhang, Fang Tian, Peng-Peng Liu, Hou-Yi Ma, Yi Ding

Journal of Electrochemistry

The nanoporous gold(NPG) electrodes with uniform pore sizes and ligaments were prepared by using a simple dealloying method.The as-prepared NPG showed high catalytic activity towards the oxidation of formic acid and formaldehyde.After tiny amount of platinum was deposited onto the NPG substrate,not only the structure stability of NPG was greatly improved,but also the Pt-Au bimetallic catalysts displayed the better catalytic activity and the stronger poison resistance towards the electrooxidation of small organic molecules than the bulk platinum due to synergistic effect between Au and Pt compositions.

Go to article

Preparation And Catalytic Activity Of Nanostructured Pd And Au-Pd Thin Films, Cui-Cui Qiu, Jin-Tao Zhang, Fang Tian, Hou-Yi Ma May 2008

Preparation And Catalytic Activity Of Nanostructured Pd And Au-Pd Thin Films, Cui-Cui Qiu, Jin-Tao Zhang, Fang Tian, Hou-Yi Ma

Journal of Electrochemistry

The nanostructured Pd thin films were directly formed on the glassy carbon electrode(GCE) substrates by using potential cycling method.The as-prepared Pd thin films deposited onto the GCE were able to absorb enough amount of hydrogen in acidic solutions at the cathodic potentials more negative than the hydrogen evolution potential.Moreover,the absorbed hydrogen could be used as the reducing agent to reduce gold(III) ions to Au nanoclusters,thereby forming bimetallic Au-Pd thin films on the GCE substrate.SEM and cyclic voltammetry characterization demonstrated that the Au-Pd thin films display much higher catalytic activity towards the electro-oxidation of ethanol than the pure Pd thin films.

Go to article

A Study On Supercapacitor Based On Aligned Carbon Nanotubes, Xiao-Yan Ye, Yan-Zhi Wang, Hai-Yan Song, Zhuo Sun, Pin-Gang He, Yu-Zhi Fang Feb 2008

A Study On Supercapacitor Based On Aligned Carbon Nanotubes, Xiao-Yan Ye, Yan-Zhi Wang, Hai-Yan Song, Zhuo Sun, Pin-Gang He, Yu-Zhi Fang

Journal of Electrochemistry

Large scale vertically aligned carbon nanotubes(ACNTs) with uniform length and diameter were prepared by the pyrolysis of iron(Ⅱ) phthalocyanine at low pressure.The ACNTs were activated by electrolyte-activation,acid-activation or electrochemical activation.The performance of the capacitor based on activated ACNTs was characterized by cyclic voltammograms which was of rectangular shape,impedence spectroscopy in which the phase is above 80° and the result specific capacitance was 16～32 F/g,which suggest that the ACNTs are the promising material for the supercapacitor.

Go to article

Mechanism Of The Cathode Reduction Of Ti(Ⅳ) In Molten Na3Alf6-Alf3, Hai-Bin Sun, Xiu-Rong Zuo, Zhi-Guo Zhong, Xue-Hui Hu Feb 2008

Mechanism Of The Cathode Reduction Of Ti(Ⅳ) In Molten Na3Alf6-Alf3, Hai-Bin Sun, Xiu-Rong Zuo, Zhi-Guo Zhong, Xue-Hui Hu

Journal of Electrochemistry

The mechanism of TiO2 electrode process has been investigated by cyclic voltammetry and chronopotentiometry on the tungsten filament in molten Na3AlF6-AlF3 salts at 990 ℃.The experimental results showed that electrochemical reduction of Ti(Ⅳ) precede were two steps,firstly Ti(Ⅳ) was reduced to Ti(Ⅱ),then Ti(Ⅱ) was reduced to Ti,namely: Ti(Ⅳ)→Ti(Ⅱ)→Ti.

Go to article

Comparison Of Catalytic Activities Of Carbon Supported Pt And Pt-Ru Catalysts For Methanol Oxidation In Neutral And Basic Media By Cyclic Voltammetry, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza Jan 2008

Comparison Of Catalytic Activities Of Carbon Supported Pt And Pt-Ru Catalysts For Methanol Oxidation In Neutral And Basic Media By Cyclic Voltammetry, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza

Turkish Journal of Chemistry

The catalytic activities of an equal amount of 3 different carbon supported catalysts containing 10% Pt, 20% Pt + 10% Ru, and 30% Pt were evaluated in neutral and basic media for methanol oxidation by cyclic voltammetry. The prominent oxidation peak for methanol appeared in the forward anodic sweep at around 1.0 V in neutral medium, while in basic medium it appeared at significantly lower potential close to 0.2 V. The peak current for methanol oxidation was higher on a catalyst containing higher Pt loading. The comparison of polarization behavior of 20% Pt + 10% Ru and 30% Pt catalysts …

Go to article

Electro-Chemical Oxidation Kinetics Of The V(Iv) In The Sulfuric Acid Solution, Yong-Lian Qiao, Qian Xu, Jie Zhang, Yu-Chun Zhai Aug 2007

Electro-Chemical Oxidation Kinetics Of The V(Iv) In The Sulfuric Acid Solution, Yong-Lian Qiao, Qian Xu, Jie Zhang, Yu-Chun Zhai

Journal of Electrochemistry

The electro-chemical oxidation kinetics for V(IV) in the sulfuric acid solution were investigated by cyclic voltammetry and steady state polarization curves at a graphite,platinum or conducting polymer electrode.Some kinetics parameters for the electrochemical reaction of V(IV) were calculated according to the Tafel curves.The results showed that the exchange current density and reversibility of V(V)/V(IV) redox reaction at the graphite electrode is largest among the three electrodes.There is the broadest extent of water stability and large oxidgen evolution potential when the conducting polymer was used as a working electrode in the solution of VOSO4(0.5 mol/L) and H2SO …

Go to article

Preparation Of Manganese/Chromium Hexacyanoferrate Modified Glassy Carbon Electrode And Its Electrochemical Behavior, Sheng-Tao Zhang, Xiao-Yan Han, Ming-Yue Xue Aug 2007

Preparation Of Manganese/Chromium Hexacyanoferrate Modified Glassy Carbon Electrode And Its Electrochemical Behavior, Sheng-Tao Zhang, Xiao-Yan Han, Ming-Yue Xue

Journal of Electrochemistry

A film of poly(manganese/chromium hexacyanoferrate)(MnCrHCF)is formed on the glassy carbon electrode(GCE) by Cyclic Voltammetry scanning,and its electrochemical behavior was studied.Factors affecting the electro-deposition of the film such as pH values and sustaining electrolytes,were discussed.And mechanism of the reaction was investigated.

Go to article

The Voltammetric Study Of The Reduction Of Tetraalkylammonium Perchlorate By Fe(Tpp)2-, Chathra Shirani De Silva, Michael D. Ryan Jul 2007

The Voltammetric Study Of The Reduction Of Tetraalkylammonium Perchlorate By Fe(Tpp)2-, Chathra Shirani De Silva, Michael D. Ryan

Chemistry Faculty Research and Publications

Tetraalkylammonium ions react with Fe(TPP)2− to form Fe(TPP)(R)− and trialkylamine. The tetrabutylammonium cation was verified to be the source of the alkyl group in the product, Fe(TPP)(R)−, by using (1H5C2)3(2H5C2)N− as the cation and 2H NMR. The reaction of Fe(TPP)2− with Bu4N− was monitored by cyclic voltammetry and thin layer spectroelectrochemistry. The activation parameters were measured, and were most consistent with an electron transfer (ET) mechanism. The rate of the reaction of tetramethyl and tetraethylammonium ions with Fe(TPP) …

Go to article

Electrochemical Behavior And Determination Of β,β-Dimethyl-Acry-Lalkannin, Li-Qing Lin, Jing-Hua Chen, Hong-Yan Wan, Xin-Hua Lin May 2007

Electrochemical Behavior And Determination Of β,β-Dimethyl-Acry-Lalkannin, Li-Qing Lin, Jing-Hua Chen, Hong-Yan Wan, Xin-Hua Lin

Journal of Electrochemistry

The electrochemical behavior of the β,β-dimethyl-acry-lalkannin and a novel differential pulse voltammetric method for the determination of the β,β-DAL content were studied.Experiments indicated that the β,β-DAL has excellent adsorbability and the electrochemical reaction is a reversible two-electro and two-proton process.In phosphate buffer solution(pH 4.6),the differential pulse voltammograms for β,β-DAL reduction signals from +0.8~-0.4 V were monitored.The relationship between reduction peak current and concentration of β,β-DAL is linear in the range of 1.3×10-7~ 1.7×10-6 mol/L(r=0.9996).The detection limit is 4.0×10-8 mol/L.This method is sensitive and reliable for the determination of the β,β-DAL in radix with satisfactory results.

Go to article

Study On The Electrogeneration And Properties Of Superoxide Ion In Aprotic Media By Using Carbon Nanotubes Powder Microelectrode, Ying-Liang Wei, Chen Shao, Hui Feng May 2007

Study On The Electrogeneration And Properties Of Superoxide Ion In Aprotic Media By Using Carbon Nanotubes Powder Microelectrode, Ying-Liang Wei, Chen Shao, Hui Feng

Journal of Electrochemistry

Multi-wall carbon nanotubes are filled in the cavity at the tip of a microelectrode to form a carbon nanotubes powder microelectrode(CNTs-PME).The CNTs-PME is used to study the electrochemical reduction of oxygen in aprotic media.It is a nearly reversible redox process of the O2/O2- couple at the CNTs-PME in the dimethyl sulfoxide(DMSO)solution.The heterogeneous electron transfer rate constant(ks)can be measured by steady-state voltammogram and the result is 9.8 10-3cm /s.As a weak oxidant,the reaction of O2- with epinephrine was studied by cyclic voltammetry.Additionally,the reaction of O2- with benzoic acid was also discussed …

Go to article

Voltammetric Behavior And Electrocatalytic Properties Of Hemoglobin At Glassy Carbon Electrode Modified With Lauric Acid, Xin-Rui Miao, Xu-Hong Zhang, Ying Xie May 2007

Voltammetric Behavior And Electrocatalytic Properties Of Hemoglobin At Glassy Carbon Electrode Modified With Lauric Acid, Xin-Rui Miao, Xu-Hong Zhang, Ying Xie

Journal of Electrochemistry

The electrochemical behavior of hemoglobin at glassy carbon(GC)electrode modified with Lauric Acid was studied.In the potential of +0.6～-0.7 V(vs.Ag/AgCl),an irreversible cathodic peak was observed at-0.3 V at the scan rate of 20 mV·s-1.In the medium of 0.02 mol·L-1 KH2PO4-Na2HPO4(pH 7.0),ip increased with the increasing concentration of Hb and the value of pH.The peak currents were proportional to the concentrations of hemoglobin in the range of 1.00×10-8～5.00×10-9 mol·L-1 and 1.92×10-6～2.06×10-7 mol·L-1.The data was analyzed in details by simulating in order to …

Go to article

Effects Of Direct Current Bias Potentials On Lipid Membranes Forming On A Glassy Carbon Electrode, Yu-Hui Li, Hong-Wei Zhang, Gui-Lan Song, Zhan-Jun Zhang, Sheng-Min Cai Feb 2007

Effects Of Direct Current Bias Potentials On Lipid Membranes Forming On A Glassy Carbon Electrode, Yu-Hui Li, Hong-Wei Zhang, Gui-Lan Song, Zhan-Jun Zhang, Sheng-Min Cai

Journal of Electrochemistry

The effects of direct current(DC) bias voltage on the structure of lipid membranes forming on a glassy carbon electrode(GCE) was investigated by cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS).The experiment showed that the lipid membranes can be formed with either positive or negative bias potential exerted.When bias voltage was exerted,bilayer lipid membranes tended to form due to the electrostatic interaction between the superficial positive charges on the polarized electrode and the negative charged part of PC.When the positive bias voltage overrun the range,the lacunas on s-BLMs would increase,and the BLMs would be broken.A proper equivalent circuit was nonlinearly fitted,based on the …

Go to article

Studies On Performance And Electrode Materials For All Vanadium Flow Battery, Jun Yuan, Qing-Chun Yu, Yi-Feng Liu, Liang-Liang Ma, Yi-Hua Wu Aug 2006

Studies On Performance And Electrode Materials For All Vanadium Flow Battery, Jun Yuan, Qing-Chun Yu, Yi-Feng Liu, Liang-Liang Ma, Yi-Hua Wu

Journal of Electrochemistry

In this paper,cyclic voltammetry has been used to study the electrochemical performance of the treated and untreated graphite,soft graphite and PAN-carbon cloth in vanadium sulfate solution.The results show that: the reversibility of reaction can be improved on the surface of treated electrode,and the current can also increase;the electrochemical performance of treated electrode is remarkably enhanced;in the process of charge/discharge,the charge current can reach up to 20 mA/cm2,and discharge current up to 15 mA/cm2;surface morphology of the treated and untreated graphite show that the treatment can change the surface structure of electrode and also add the reaction …

Go to article

Investigation Of The Direct Electrochemical Reduction Of Cr2O3 Powder In Molten Cacl2 By A Metallic Cavity Electrode, Guo-Hong Qiu, Di-Hua Wang, Xian-Bo Jin, Xiao-Hong Hu, Zheng Chen Aug 2006

Investigation Of The Direct Electrochemical Reduction Of Cr2O3 Powder In Molten Cacl2 By A Metallic Cavity Electrode, Guo-Hong Qiu, Di-Hua Wang, Xian-Bo Jin, Xiao-Hong Hu, Zheng Chen

Journal of Electrochemistry

A metallic cavity electrode is used for further investigation of the electrochemical behaviour of Cr2O3 powder in molten CaCl2(Na: ~0.02% by mass,Mg: < 0.005% by mass) at 900 ℃.The Cr2O3 powder reduction mechanism was confirmed in line with EDX and SEM analysis of the potentiostatic electrolysis products.The correlations between the particle size of metallised product and the electrolysis potential,or electrolysis time were analysed.

Go to article

The Electrochemical Study On Self-Assembled Monolayers Of Sodium Stearate Surfactant On Oil/Water Interface, Li-Na Tang, Feng-Ping Wang, Yong-Chun Zhu Aug 2006

The Electrochemical Study On Self-Assembled Monolayers Of Sodium Stearate Surfactant On Oil/Water Interface, Li-Na Tang, Feng-Ping Wang, Yong-Chun Zhu

Journal of Electrochemistry

The self-assembled monolayers of sodium stearate surfactant on oil/water interface was investigated by CV with copper ion as probe.The self-assembling process includes four stages,and forms a stable assembly.The electrochemical oxidation of copper ion at assembled surface is a combine controlled process both surface and diffusion with regression equation as ip = 9.214-3.889 v1/2 +0.5809v,r=0.9978,compared with the oil covered bared electrode,it is a complete surface controlled.

Go to article

Study On The Preparetion And Electrochemical Beavior Of Nitrogen Doped Tetrahedral Amorphous Carbon Electrode, Ke Liu, Guang-Fu Wang, Zheng-Hao Wang Aug 2006

Study On The Preparetion And Electrochemical Beavior Of Nitrogen Doped Tetrahedral Amorphous Carbon Electrode, Ke Liu, Guang-Fu Wang, Zheng-Hao Wang

Journal of Electrochemistry

taC∶N films are a good materials for semiconductor electrodes.But further studies are hampered by the ohmic contact problem,which occurs between the silicon and the lead.By studying the influence of heat treatment on the film's property,it is believed that ohmic contact should be made on the silicon first,and then the film be deposited.A set of taC∶N electrodes with various nitrogen content have been prepared.CV study indicates that the cathodic limits move slowly to positive direction.while the anodic limits are unchanged with the increasing of nitrogen content.As a result,the electrochemical windows get narrow either.

Go to article

An Electrochemical Investigation Of Methanol Crossover In Dmfcs, Meng-Di You, Xuan Cheng, Lian Liu, Lu Zhang May 2006

An Electrochemical Investigation Of Methanol Crossover In Dmfcs, Meng-Di You, Xuan Cheng, Lian Liu, Lu Zhang

Journal of Electrochemistry

Methanol crossover and its effect on the open-circuit voltage(OCV) in DMFCs were studied usingcyclic voltammetry and chronoamperometry under stationary condition and at ambient temperature.An H-shapecell was constructed and a simulative DMFC test was carried out to investigate methanol crossover through Na-fion(117 from anode to cathode.The results revealed thatthe amountof methanol in the cathode side is depend-ent upon the time of penetration.As the concentration of methanol increased,the hydrogen adsorption-desorptionon the surface of electrode was suppressed and a shoulder peak appeared during the forward sweep for methanoloxidation.The simulative DMFC test also showed that the methanol crossover caused a sudden decline in theOCV.

Go to article

Mechanism Of Self Discharge Performance Improvement In The Ni-Mh Batteries With Naoh Electrolyte, Xiao-Feng Li, Tong-Chi Xia, Hui-Chao Dong, Yan-Wei Wei Feb 2006

Mechanism Of Self Discharge Performance Improvement In The Ni-Mh Batteries With Naoh Electrolyte, Xiao-Feng Li, Tong-Chi Xia, Hui-Chao Dong, Yan-Wei Wei

Journal of Electrochemistry

The self-discharge performance and charge efficiency at 60 ℃ for Ni-MH battery can be markedly enhanced by using NaOH electrolyte instead of KOH electrolyte.Both the results of electrochemical impedance spectroscopy and cyclic voltammetry tests indicate that the separation of H2 from the negative electrode may be partly blocked in the former because of the change of the adsorption/desorption behavior of H on the surface of the negative electrode,thus results in an improvement of self-discharge performance of the battery.

Go to article

Electrochemical Oxidation Of Organic Additives In Tin Plating Electrolytes, Yin-Mei Cheng, Lan-Kun Cai, Qiang Song Nov 2005

Electrochemical Oxidation Of Organic Additives In Tin Plating Electrolytes, Yin-Mei Cheng, Lan-Kun Cai, Qiang Song

Journal of Electrochemistry

Cyclic voltammetry(CV) was used to characterize the voltammetric behaviours of organic additives, e.g. PSA(phenolsulfonic acid) EN(ethoxylatedα-naphthol) and ENSA(ethoxylatedα-naphthol sulfonic acid), on the anode surface. In PSA solutions, an anodic peak was obtained and the peak potential was about 1.2V. In EN and ENSA solutions, two anodic peaks were obtained and the peak potentials were about(0.95V) and 1.3V. The products of galvanostatic electrolysis were separated by HPLC(high performance liquid chromatography) and analyzed by EI/MS(electron ionizing mass spectrometry). The mechnism of the electrochemical oxidation was also disussed.

Go to article

A Preliminary Study Of Influence Of The Chain Length Of Alkanethiols On The Electrochemical Behavior Of Redox Self-Assembled Multilayer Thin Films, Yun-Feng Wang, Zhan-Jun Zhang Aug 2005

A Preliminary Study Of Influence Of The Chain Length Of Alkanethiols On The Electrochemical Behavior Of Redox Self-Assembled Multilayer Thin Films, Yun-Feng Wang, Zhan-Jun Zhang

Journal of Electrochemistry

Alkanethiols and ferrocene derivates were used to construct redox self-assembled double-or triplex-layer thin films, which acted as a model of redox self-assembled multilayer thin films (SAMTFs) to study the in-fluence of alkanethiols chain length on the electrochemical behavior of the SAMTFs. The rate of electron transferreaction decreased exponentially with the distance between the Fc groups and the underlying electrodes. The in-fluence of chain length on the electrochemical behaviors of the SAMTFs was inconsistent under different situa-tions. On the experimental situation of this work, when electroactive groups were closer to the electrodes, SAMTFs by longer chains of alkanethiols displayed stronger electrochemical …

Go to article

Surface-Enhanced Raman Spectra Of Cytosine Adsorbed On A Roughened Gold Electrode, Yuan-Fei Wu, Jian-Feng Li, De-Yin Wu, Bin Ren, Zhong-Qun Tian Aug 2005

Surface-Enhanced Raman Spectra Of Cytosine Adsorbed On A Roughened Gold Electrode, Yuan-Fei Wu, Jian-Feng Li, De-Yin Wu, Bin Ren, Zhong-Qun Tian

Journal of Electrochemistry

Cytosine adsorbed on a roughened gold electrode has been investigated by using electrochemical cyclic voltammetry and surface-enhanced Raman spectroscopy (SERS). The results indicate that cytosine was adsorbed on the Au electrode in a perpendicular orientation via the N3 position. As the maximum enhancement of ring breathing mode appears at negative potentials compared with other modes, both the electromagnetic enhancement and the charge transfer mechanism were considered to contribute to the SERS intensity. The binding interaction between cytosine and the gold electrode was weakened when the potential was negatively moved. The result also indicates that the SERS technique can be used …

Go to article

The Fabrication And Electrochemical Studies On Carbon Nanotube Array Electrodes, Quan-Yong Gao, Jing Zhang, Yong Yang Feb 2005

The Fabrication And Electrochemical Studies On Carbon Nanotube Array Electrodes, Quan-Yong Gao, Jing Zhang, Yong Yang

Journal of Electrochemistry

An improved technique for fabrication of carbon nanotube array electrodes has been proposed in this work. Firstly, carbon nanotubes (CNs) array electrodes were prepared by combsination of Chemical Vapor Decomposition (CVD) method and sputtering techniques in anodized aluminum oxide (AAO) membrane. The CNs/AAO was immersed into HF solution to remove the barrier layer. Controlling the immersing time, the CNs array electrodes with different length contacted with electrolyte can be prepared. The morphology of CNs array electrodes was observed by SEM. The electrochemical properties of CNs array electrodes were investigated by cyclic voltammetry and electrochemical impedance spectroscopy. Cyclic voltammetric curves of …

Go to article

Study On Electrochemical Performance Of Electroless Cobalt Coating For Microencapsution Of Hydrogen Storage Alloys, Tong-Chi Xia, Sheng-Li Zhang, Shu-Xin Wang, Kun Huang, Wen-Zeng Tian May 2004

Study On Electrochemical Performance Of Electroless Cobalt Coating For Microencapsution Of Hydrogen Storage Alloys, Tong-Chi Xia, Sheng-Li Zhang, Shu-Xin Wang, Kun Huang, Wen-Zeng Tian

Journal of Electrochemistry

The chemical cobalt plating method is used to treat on the hydrogen storage alloys. Effect of the surface treatment on the electrochemical performance of MH eletrodes was investigated by carrying out experimental methods of CV, AC and charge/discharge cycle tests. The results showed that after microencapsulation with cobalt, the impedance of electrochemical reaction on the surface and polarization during chare/discharge process was markedly decreased; and the electrocatalytic activity on the surface, discharge capacity, charge efficiency was improved. It was also indicated that the anode reaction of MH electrode treated was controlled by diffusion process.

Go to article

Photophysical Properties And Electrochemistry Of The N,N'-Bis-N-Butyl Derivative Of Naphthalene Diimide, Yevgen Posokhov, Serap Alp, Banu Köz, Yusuf Di̇lgi̇n, Siddik İçli̇ Jan 2004

Photophysical Properties And Electrochemistry Of The N,N'-Bis-N-Butyl Derivative Of Naphthalene Diimide, Yevgen Posokhov, Serap Alp, Banu Köz, Yusuf Di̇lgi̇n, Siddik İçli̇

Turkish Journal of Chemistry

The spectral-luminescent properties and electrochemistry of the N,N'-bis-n-butyl derivative of naphthalene diimide were studied. The main photophysical parameters (quantum yield, rate constants of fluorescence and of non-radiative deactivation and fluorescence lifetime) were determined. The LUMO value (-3.51 eV) was determined by cyclic voltammetry. The N,N'-bis-n-butyl derivative of naphthalene diimide (BBND) shows 2 reversible reduction steps (-1.19 V and -1.75 V vs. Ferrocene) in chloroform. Quenching the fluorescence emissions of aromatic donor molecules in acetonitrile revealed the electron acceptor ability of the studied naphthalene diimide derivative. It has been found that, in contrast to perylene diimide derivatives, which form \pi-electron donor-acceptor …

Go to article

The Electroless Plating Ni-Fe-P Alloy And Its Voltammetric Behavior, Sen-Lin Wang, Hui-Huang Wu Aug 2003

The Electroless Plating Ni-Fe-P Alloy And Its Voltammetric Behavior, Sen-Lin Wang, Hui-Huang Wu

Journal of Electrochemistry

Electroless Ni-Fe-P alloy deposition from an alkaline bath, containing sodium hypophosphite as reducer, boric acid as buffer agent and sodium citrate as complexing agent, was investigated. To increase the plating rate and to inprove the bath stability, the deposition parameters were optimized. The effects of process parameters (pH, temperature and mole ratio of [Fe2+]/([Ni2+]+[Fe2+]) on the plating rate and deposit composition were examined and it was found that the presence of ferrous sulfate in the bath has an inhibitory effect on the alloy deposition. As a consequence, the percentage of iron in the electroless …

Go to article

Electrochemical Monitoring On The Deactivation Of A Metallic Oxide Anode, Li-Kun Xu, Shi-Zhe Song, Ting-Yong Wang, Guang-Zhang Chen May 2003

Electrochemical Monitoring On The Deactivation Of A Metallic Oxide Anode, Li-Kun Xu, Shi-Zhe Song, Ting-Yong Wang, Guang-Zhang Chen

Journal of Electrochemistry

The process of accelerated life test of an IrO2/Ta2O5 coated titanium anode was monitored using cyclic voltammetry and electrochemical impedance spectroscopy. The vatiation with electrolysis time of anodic voltammetric charge Q*, the double layer capacitance Cdl,the oxide film resistance Rf and the charge transfer resistance Rct for oxygen evolution was measured. A deactivation mechanism was proposed based on the observation results.

Go to article

A Novel, Semi-Pilot Scale Electrolysis System For The Production Of P-Aminophenol, Kamran Polat Jan 2003

A Novel, Semi-Pilot Scale Electrolysis System For The Production Of P-Aminophenol, Kamran Polat

Turkish Journal of Chemistry

Cyclic voltammetry (CV) and preparative electrolysis techniques were used to investigate the reduction of nitrobenzene into (NB) p-aminophenol (p-Ap). The electrodes used in CV experiments were glassy carbon (GC), TiO_{2}/Ti, Sn and Pb. The preparative electrolyses were carried out by the use of Pb, Sn, carbon cloth and TiO_{2}/Ti electrodes. The CV data were evaluated according to Nicholson-Shain criteria, and it was deduced that the reductions on TiO_{2}/Ti and GC electrodes were irreversible and monitored by an electrochemical-chemical-electrochemical mechanism. No reduction peak was observed with Sn and Pb electrodes. Preparative electrolyses were carried out under current-controlled conditions in the presence …

Go to article

Electrochemical Behaviors Of Vanadium(V) Compounds In H2So4 Solution, Yang Liu, Hong-Tao Liu, Xi Xia Feb 2002

Electrochemical Behaviors Of Vanadium(V) Compounds In H2So4 Solution, Yang Liu, Hong-Tao Liu, Xi Xia

Journal of Electrochemistry

The electrochemical behaviors of vanadium(V) compounds(NH4VO3 and V2O5) in H2SO4 solutions were investigated by cyclic voltammetry (CV) and rotation ring disk electrode (RRDE) techniques. There were three anodic peaks and three cathodic peaks appeared on the CV plots at inert Pt electrode. But compared with the V2O5, the CV plot of NH4VO3 had one more anodic peak. There also appeared four anodic peaks at RRDE plots. We carefully analyzed these peaks and made some reasonable initial explaination.

Go to article

First Prev Next Last