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Journal of Electrochemistry

Articles 1411 - 1440 of 2294

Full-Text Articles in Physical Sciences and Mathematics

Novel Electrochemical Method For Synthesis Of Nanostructured Materials Of Noble Metals Based On Poly(N-Vinylpyrrolidone) (Pvp), Wei Pan Nov 2006

Novel Electrochemical Method For Synthesis Of Nanostructured Materials Of Noble Metals Based On Poly(N-Vinylpyrrolidone) (Pvp), Wei Pan

Journal of Electrochemistry

Gold nanocrystals with controllable size were synthesized through a simple electroreduction method using poly(N-vinylpyrrolidone)(PVP) of different polymerization degree as both stabilizer and shape-controller for gold nanoclusters.Individual gold nanoparticles spontaneously assembled into the wire-and ring-shaped nanoparticle aggregates depending on the PVP's dynamic stretching and curling,and precursor nanoparticles grew into flat,single-crystalline nanoprisms with thickness of dozens of nanometers based on the oriented aggregation between particles.Besides,core-shell Au/Ag nanoparticles were conveniently synthesized through two-step electroreduction of noble metal ions in the presence of PVPK30.The electrochemical synthetic method based on PVP provides a new path for preparation of noble metal nanostructured materials with different shape …

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Phase-Transfer Technique For Polymer-Protected Noble Metal Nanoparticles, Xing-Li Feng Nov 2006

Phase-Transfer Technique For Polymer-Protected Noble Metal Nanoparticles, Xing-Li Feng

Journal of Electrochemistry

A novel phase-transfer method was developed based on the decrease of PVP's solubility in water with increasing temperature,by means of which PVP-protected gold,silver and platinum nanoparticles can be conveniently transferred from aqueous phase to 1-butanol phase.Monodispersed metal nanoparticles were electrochemically synthesized at first in the aqueous,and then 1-butanol of appropriate volume was added to the aqueous phase.Heating the oil-water mixture to 80 ℃ under vigorous stirring would make metal nanoparticles leave the aqueous phase and enter into the 1-butanol phase,with high phasetransfer efficiency and without aggregation between nanoparticles.An electrochemical method to synthesize metal nanoparticles in the oil-water mixtures was further …

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Study Of The Electrooxidation Of Glycerol On Oxide And Pd/C Composite Catalysts, Zhi-Yuan Yan, Chang-Wei Xu, Pei-Kang Shen Nov 2006

Study Of The Electrooxidation Of Glycerol On Oxide And Pd/C Composite Catalysts, Zhi-Yuan Yan, Chang-Wei Xu, Pei-Kang Shen

Journal of Electrochemistry

Oxide and Pd on carbon composite catalysts have been prepared by intermittent microwave heating(IMH) method.The performance of the catalysts for glycerol oxidation in alkaline solution is studied by electrochemical techniques.It is shown that the Pd/C catalyst is active for glycerol electrooxidation.However,the oxide-Pd/C catalysts are even better in terms of the onset potential that is more negative and peak current density.The ratio of oxide to Pd is optimized according to the electrochemical measurement.The results reveal that the addition of oxide into the Pd/C induces the synergistic effect for glycerol electrooxidation.

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Electrochemical Properties Of The Modified Carbon Nanotubes, Chun-An Ma Nov 2006

Electrochemical Properties Of The Modified Carbon Nanotubes, Chun-An Ma

Journal of Electrochemistry

Powder micro-electrodes were prepared from raw carbon nanotubes and carbon nanotubes modified by carboxyl.The electro-reduction properties of both the raw and open-ended carbon nanotubes in p-Nitrophenol solution were investigated.The FTIR spectrum result indicated that the functional groups are successfully fixed on the surface of the carbon nanotubes after nitric acid treatment.The cyclic voltammetry results show that the electrochemical activity of carboxyl-modified carbon nanotubes was improved.The mechanism of electro-(reduction) for the carbon nanotubes after acid treatment was discussed.

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Studies And Applications Of Phosphoric Acid Treatment On Low Voltage Formed Aluminum Foils, Lan Sun Nov 2006

Studies And Applications Of Phosphoric Acid Treatment On Low Voltage Formed Aluminum Foils, Lan Sun

Journal of Electrochemistry

The surface of low voltage formed foil for Al electrolysis capacitors is treated with phosphoric acid solution.The effects of concentration of phosphoric acid solution,temperature and process time on specific capacitance and the time of hydration resistance with standing voltage are studied.The optimum condition is presented.The properties of low voltage formed foil have been improved by applying this method on the product line.

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Fabrication And Characterization Of Gadolinium Hexacyanoferrate Modified Electrode, Yan-Mao Shi, Pan Du, Ping Wu, Yao-Ming Zhou, Chen-Xin Cai Nov 2006

Fabrication And Characterization Of Gadolinium Hexacyanoferrate Modified Electrode, Yan-Mao Shi, Pan Du, Ping Wu, Yao-Ming Zhou, Chen-Xin Cai

Journal of Electrochemistry

A new electroactive polynuclear inorganic compound of rare earth metal hexacyanoferrate,gadolinium hexacyanoferrate(GdCHF),was prepared by electrochemically deposition on the surface of a glassy carbon electrode with a potential cycling procedure.The result of SEM indicated that the GdHCF was in the form of particles adhered on the surface of electrode.There were two different shapes and sizes of GdHCF forming on the surface of electrode.FTIR spectrum of GdHCF showed a very strong and sharp peak,which located at 2062.5 cm~(-1) and corresponded to the stretching vibration of the C≡N group in the GdHCF.The cyclic voltammetric results indicated that the GdHCF/GC electrode exhibited two pairs …

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The Synthesis,Structure And Electrochemical Performances Of Lithium Iron Phosphate, Hui Xie Nov 2006

The Synthesis,Structure And Electrochemical Performances Of Lithium Iron Phosphate, Hui Xie

Journal of Electrochemistry

The lithium iron phosphate cathode materials were synthesized by solid-state reaction combined high-rate ball milling under the temperature ranging from 400 ℃ to 700 ℃.The crystalline structure,morphology of particles,and electrochemical performance of the sample were investigated by X-ray diffraction,scanning electron microscopy and charge-discharge test.The results showed that the sintering temperature had great influences on the crystal structure,morphology and electrochemical performances of LiFePO_(4).The sample synthesized under 600℃ showed the best charge-discharge performances with the first specific discharge capacity of(128.8) mAh/g and the 15~(th) specific discharge capacity of 129.1 mAh/g at 0.1C rate,each charge-discharge cycling efficiency being 99.7%.Also the sample showed good …

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Deep Treatment Of Pulping Wastewater Using Three Phase Fluidized Bed Electrode Reactor, Dan Wu Nov 2006

Deep Treatment Of Pulping Wastewater Using Three Phase Fluidized Bed Electrode Reactor, Dan Wu

Journal of Electrochemistry

Treatment of pulping wastewater by using a novel electrochemical reactor,i.e.the three phase fluidized bed electrode,reactor were invesigated.The effects of air flow rate,applied voltage,pH value and FeSO_(4) concentration on electrolysis efficiency were investigated.It was clearly shown that the 20 V of voltage,0.3 m~(3) h~(-1) of air flow rate,1000 mg L~(-1) of FeSO_(4) concentration and pH≈2.5 were its best conditions.COD removal could be 70.1% under these conditions.

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Electrochemical Characterization Of Positive Electrode Material Lini_(1/3)Co_(1/3)Mn_(1/3)O_2 In Different Electrolytes, Jing-Jing Liu, Wei-Hua Qiu, Ling-Yan Yu, Hai-Lei Zhao, Tao Li Nov 2006

Electrochemical Characterization Of Positive Electrode Material Lini_(1/3)Co_(1/3)Mn_(1/3)O_2 In Different Electrolytes, Jing-Jing Liu, Wei-Hua Qiu, Ling-Yan Yu, Hai-Lei Zhao, Tao Li

Journal of Electrochemistry

Cathode materials LiNi_(1/3)Co_(1/3)Mn_(1/3)O_(2) were prepared by low-heating solid-state reaction.The micro-structure and morphology of as-synthesized materials have been investigated by using XRD and SEM.The compatibilities of LiNi_(1/3)Co_(1/3)Mn_(1/3)O_(2) with purchased LiPF_(6)/ EC+DMC+DEC electrolyte and prepared LiBOB/EC+DEC+EMC electrolyte have also been studied.The Li/LiNi_(1/3)Co_(1/3)Mn_(1/3)O_(2) batteries showed excellent electrochemical properties in the LiPF_(6)/ EC+DMC+DEC electrolyte.Reversible discharge capacities of 167、163、163、157、147mAh/g at 0.5C、1C、1.5C、2C、3C rate between 2.7~4.35 V,with stable cycling performances have been obtained.Comparatively,the specific capacity of 160 mAh/g at 0.5C was obtained in LiBOB/EC+DEC+DEC electrolyte,which was just a little lower than that in the other electrolyte.However,the high rate capability of the materials in LiBOB/EC+DEC+DEC was not as …

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Electrodeposition Of Nano-Sb-Zn Alloy In Acetamide-Urea-Nabr-Kbr Melt, Peng Liu, Xin-Ai Guo, Ye-Xiang Tong, Qi-Qin Yang Aug 2006

Electrodeposition Of Nano-Sb-Zn Alloy In Acetamide-Urea-Nabr-Kbr Melt, Peng Liu, Xin-Ai Guo, Ye-Xiang Tong, Qi-Qin Yang

Journal of Electrochemistry

The electroreduction of Zn(II) and Sb(III) in acetamide-urea-NaBr-KBr(343 K) were studied by cyclic volatmmetry.The reduction of Zn(II) or Sb(III) to the metals is an irreversible process.The transfer coefficient of Zn(II)+2e→Zn and Sb(III) +3e→Sb were calculated to be 0.231 and 0.319,the diffusion coefficient of Zn(II) and Sb(III) in the melt were determined as 1.70 10~(-6) and 3.21 10~(-6) cm~(2)· s~(-1) respectively.The Zn-Sb films with different Zn content from 29.67 at% to 97.34 at% were electrodeposited in acetamide-urea-NaBr-KBr melt at 343 K by controlling the deposition potential and the Zn(II)/Sb(III) molar ratio.The morphology of Zn-Sb film was observed by SEM.Zn-Sb film comprises …

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The Influence Of Pva As Disperser On Lifepo_(4) Synthesized By Hydrothermal Reaction, Hui-Lin Li, Hui Zhan Aug 2006

The Influence Of Pva As Disperser On Lifepo_(4) Synthesized By Hydrothermal Reaction, Hui-Lin Li, Hui Zhan

Journal of Electrochemistry

LiFePO_(4) was synthesized by means of hydrothermal reaction,in which PVA acts as disperser and glucose as carbon source.The samples were characterized by X-ray diffraction,scanning electron microscopy and electrochemical measurement.SEM results show that the sample is homogeneously composed of grains with a particle size of ca.200nm.In the charge/discharge test,the products exhibited a 3.45V discharge voltage plateau and a maximum specific capacity of 140mAh/g.After 40 cycles,its capacity only declined by 2.1%.Besides these,the mechanism for the influence of the particle size and carbon coating on the electrochemical property of LiFePO_(4)material was discussed in detail.

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Calcined Temperatures Influence On Synthesis And Electrochemistry Charactarization Of Li[Ni_(0.475)Mn_(0.475)Co_(0.05)]O_(2) For Li-Ion Batteries, Li-Qin Wang, Li-Fang Jiao, Hua-Tang Yuan Aug 2006

Calcined Temperatures Influence On Synthesis And Electrochemistry Charactarization Of Li[Ni_(0.475)Mn_(0.475)Co_(0.05)]O_(2) For Li-Ion Batteries, Li-Qin Wang, Li-Fang Jiao, Hua-Tang Yuan

Journal of Electrochemistry

Layered Li[Ni_(0.475)Mn_(0.475)Co_(0.05)]O_(2) materials have been prepared by a solid-state pyrolysis method.Experiments of XRD,SEM,cyclic voltammetry and charge/discharge cycling were carried out.It can be learned that when calclined at 800 ℃,the sample showed the highest first discharge capacity of 178.8 mAh·g~(-1) at a current density of 20 mA/g in the voltage range 2.3~4.6 V.

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Influence Of Crystallinity On The Kinetics Of Li Ion Insertation And Deinsertation In Spinel Limn_(2)O_(4), Rong-Hua Zeng, Dong-Sheng Lv, Wei-Shan Li Aug 2006

Influence Of Crystallinity On The Kinetics Of Li Ion Insertation And Deinsertation In Spinel Limn_(2)O_(4), Rong-Hua Zeng, Dong-Sheng Lv, Wei-Shan Li

Journal of Electrochemistry

Two spinel lithium manganese oxides of different crystallinity were prepared by sol-gel process and were studied by using inducfively coupled plasma,X-ray diffraction,scaning electron micrographs,constant charging and discharging,cyclic voltammetry and electrochemical impedance spectrometry,the results show that the sample treated under 700 ℃ has higher crystallinity than the sample treated under 500 ℃,however,the sample with lower crystallinity has higher discharge capacity and better cyclic performance that due to quicker charge exchange speed and quicker diffusion speed of Li-ion.

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Investigation Of The Direct Electrochemical Reduction Of Cr_(2)O_(3) Powder In Molten Cacl_(2) 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 Cr_(2)O_(3) Powder In Molten Cacl_(2) 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(Cr_(2)O_3) powder in molten CaCl_(2)(Na: ~0.02% by mass,Mg: < 0.005% by mass) at 900 ℃.The Cr_(2)O_(3) 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.

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The Electrochemical Study On Self-Assembled Monolayers Of Sodium Stearate Surfactant On Oil/Water Interface, Li-Na Tang Aug 2006

The Electrochemical Study On Self-Assembled Monolayers Of Sodium Stearate Surfactant On Oil/Water Interface, Li-Na Tang

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 i_(p) = 9.214-3.889 v~(1/2) +0.5809v,r=0.9978,compared with the oil covered bared electrode,it is a complete surface controlled.

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Pre-Oxidative Amperometric Glucose Biosensor Incorporated With Carbon Nanotube And Pbo_(2), Hong-Lan Qi, Cheng-Xiao Zhang Aug 2006

Pre-Oxidative Amperometric Glucose Biosensor Incorporated With Carbon Nanotube And Pbo_(2), Hong-Lan Qi, Cheng-Xiao Zhang

Journal of Electrochemistry

A pre-oxidative amperometric glucose biosensor incorporated with carbon nanotube,ferrocenemonocarboxylic acid and PbO_(2) was designed.The interferences coming from reduced substances,such as ascoribic acid and urine acid were eliminated by PbO_(2).The oxidative current is linear at the potential of +0.40 V(vs.SCE) to the concentration of glucose in the range from 0.50 to 20 mmol·L~(-1),and the detection limit of glucose is 0.1 mol L~(-1).The relative standard deviation is 3.3% for seven successive assays at 5.0 mmol·L~(-1)glucose.This biosensors have been applied to determination of the glucose in serum with satisfying results.

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Research Of Explosion Mechanism Of Lithium-Ion Battery, Yu-Hong Chen, Zhi-Yuan Tang Aug 2006

Research Of Explosion Mechanism Of Lithium-Ion Battery, Yu-Hong Chen, Zhi-Yuan Tang

Journal of Electrochemistry

The heat character of Lithium-ion battery materials and explosion mechanism of Lithium-ion cells under the overcharge,short-circuit and other abuse behavior are tested by C_(80) calorimeter,_()DSC and charge-discharge instrument.SEI reactions,Li_xC_(6)/electrolyte and Li_xC_(6)/PVDF reactions take place at the anodes.Electrolyte and solvent reactions happen after 178℃ and Li_(1-x)Co_(1/3)Ni_(1/3)Mn_(1/3)O_(2) decomposes after 230℃.The batteries explode at 150℃ oven test or 1.5C,5.5 V overcharge and do not explode at short-circuit.

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Preparation And Supercapacitor Properties Of Yttrium Doped Nio, Dan-Dan Han Aug 2006

Preparation And Supercapacitor Properties Of Yttrium Doped Nio, Dan-Dan Han

Journal of Electrochemistry

Yttrium doped Nano-NiO were synthesized by chemical precipitation method.Characterization and performance of the samples were studied by X-ray diffraction,the results showed that the doping Yttrium did not change the crystal structure of NiO,but the size of crystalline grain was reduced.The electrochemical properties of the electrode materials were measured in the three electrode system.Electrochemical properties of NiO were researched by cyclic voltammetry,constant current charge/discharge and AC impedance methods.It could be seen that the chemical doping improved the specific capacitance and the utilization of active materials.When the weight ratio of NiO with Y_(2)O_(3)was 1∶0.1,the composite material had the best properties.The maximum discharge …

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Recycling Of The Spent Nickel-Cadmium Batteries Based On Bioleaching Process, Liang-Shu Xia, Shi-Fu Fu, Zhong-Qing Chen Aug 2006

Recycling Of The Spent Nickel-Cadmium Batteries Based On Bioleaching Process, Liang-Shu Xia, Shi-Fu Fu, Zhong-Qing Chen

Journal of Electrochemistry

Less than 1 percent of discarded dry batteries are recovered in china.it is necessary to find an economic,fast and environmentally friendly process to recycle spent dry batteries.Bioleaching is better one of the few technology applied for the recovery of the toxic metals from hazardous spent batteries.In this study,after the acidified sludge made by the inoculated and cultured indigenous sewage sludge was acted as leaching bacteria species,the influence of the different pH values,the different residence time of the sludge in bioreactor(RTB),the leaching time,whether or not adding Fe(iron powder) to the leaching liquid on the leaching rate of Ni,Cd was tested.The results …

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Study On The Microstructure Of Pb-Sn Alloy Obtained From Quasi-Two-Dimensional Electrodeposition, Bin Sun Aug 2006

Study On The Microstructure Of Pb-Sn Alloy Obtained From Quasi-Two-Dimensional Electrodeposition, Bin Sun

Journal of Electrochemistry

A two-layered structure of eutectic-solid sulotion is formed in the microstructure of Pb-Sn alloy obtained from quasi-two-dimensional electrodeposition.It is showed that this unique structure is caused by the variation of the current density on the growth interface.When the interface is located in the front of the whole deposits,the current density is high.So the Pb and Sn can deposit together and the eutectic texture forms.When the interface is in the rear of the whole deposits,the current density is low.At this moment the electrodeposition of Pb is the dominant reaction,and the Pb-based solid solution appears.

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Study On The Preparetion And Electrochemical Beavior Of Nitrogen Doped Tetrahedral Amorphous Carbon Electrode, Ke Liu Aug 2006

Study On The Preparetion And Electrochemical Beavior Of Nitrogen Doped Tetrahedral Amorphous Carbon Electrode, Ke Liu

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.

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The Property Study Of Libob-Pc/Dec Electrolyte, Ying-Kun Ning, Bi-Tao Yu, Fu-Shen Li, Wei-Hua Qiu Aug 2006

The Property Study Of Libob-Pc/Dec Electrolyte, Ying-Kun Ning, Bi-Tao Yu, Fu-Shen Li, Wei-Hua Qiu

Journal of Electrochemistry

The new electrolyte salt LiBOB for Li-ion battery was synthesized in laboratory,and series of electrolytes of LiBOB and PC/DEC was compounded.The conductivity of the electrolytes was compared by changing the temperature and concentration.The cycling performance of charging-discharging was also compared by the charging-discharging test,the results showed that the varying regularity of conductivities and cycling stability and capacity were not always identical,but there were a suitable electrolyte for Li/ARG cell.The A.C.impedance and CV were used to test the compatibility of the most suitable electrolyte and ARG anode.Conclusion can be drawn that the ARG anode can be protected very well by SEI …

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Studies On Synthesis And Electrochemical Performance Of Li_(X)Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2) As Cathode Material For Lithium Ion Batteries, Xiao-Jian Guo, Jie Li, Yi-Xiao Li, Yong Yang Aug 2006

Studies On Synthesis And Electrochemical Performance Of Li_(X)Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2) As Cathode Material For Lithium Ion Batteries, Xiao-Jian Guo, Jie Li, Yi-Xiao Li, Yong Yang

Journal of Electrochemistry

A series of LiNi_(1/3)Mn_(1/3)Co_(1/3)O_(2) were synthesized by a combined hydroxides coprecipitation and calcination method.Effects of synthesizing temperature of coprecipitations and the Li∶M ratios on structure and electrochemical performance of the materials were studied.The results showed that materials synthesized with coprecipitation at room temperature(~20 ~(o)C) delivered the best electrochemical performance.Another series of cathode materials Li_(x)Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2) with different Li∶M ratios were synthesized with this method.The results showed that sintering at high temperature could cause loss of LiOH,thus more LiOH should be added.It is demonstrated that Li_(1.08)Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2) had the best electrochemical performance.

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Effects On The Structure And Electrochemical Performance Of Lifepo_(4) By Zr~(4+) Doping, Yan-Li Ruan, Zhi-Yuan Tang Aug 2006

Effects On The Structure And Electrochemical Performance Of Lifepo_(4) By Zr~(4+) Doping, Yan-Li Ruan, Zhi-Yuan Tang

Journal of Electrochemistry

Stoichiometric Zr-doped lithium iron phosphate(LiFePO_(4)) cathode material was synthesized by a solid-state reaction in an inert atmosphere.The effects of doping content on the physical and electrochemical properties of as-synthesized cathode materials were investigated.The samples were characterized by powder X-ray diffraction(XRD),and their electrochemical performance was systematically measured by impedance response and constant current charge/discharge cycling tests.The results indicate that the low concentration Zr~(4+)doping does not affect the structure of the material but considerably improves its kinetics in terms of capacity delivery and cycle performance.At 0.1C discharging rate,the reversible specific capacities of the Li_(0.99)Zr_(0.01)FePO_(4)cathode material is 135.6mAh g~(-1).After 30 cycles,the capacity fade …

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Studies On Performance And Electrode Materials For All Vanadium Flow Battery, Yuan Jun Aug 2006

Studies On Performance And Electrode Materials For All Vanadium Flow Battery, Yuan Jun

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/cm~(2),and discharge current up to 15 mA/cm~(2);surface morphology of the treated and untreated graphite show that the treatment can change the surface structure of electrode and also add the reaction area.

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Effect Of Ti Doping On The Structure And Performance Of Lini_(0.75)Co_(0.25)O_(2), Hui He, Xuan Cheng, Zhang Ying Aug 2006

Effect Of Ti Doping On The Structure And Performance Of Lini_(0.75)Co_(0.25)O_(2), Hui He, Xuan Cheng, Zhang Ying

Journal of Electrochemistry

In this study,a series of Co-doped compounds with the formula of LiNi_((0.75-x))Co_(0.25)Ti_(x)O_(2)(x=0,(0.1),0.25)was synthesized by using sol-gel method.Their structure,particle size,electrochemical properties were studied by TG,XRD,SEM and electrochemical tests.It was shown that the structure of materials changed from a hexagonal layered structure to a cubic structure as the x value increased.In particular,a mixture of hexagonal and cubic structure was presented at x =0.25.The electrochemical performance of the materials depended strongly on the amount of Ti doping.Possible effects on the structure and performance of LiNi_((0.75-x))Co_(0.25)Ti_(x)O_(2) due to Ti doping are briefly discussed based upon the experiment and computational results.

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Investigations On Electrochemical Characteristics Of Liv_(3)O_(8) Electrode In Lithium Sulfate-Water-Ethanol Electrolytes, An-Bao Yuan Aug 2006

Investigations On Electrochemical Characteristics Of Liv_(3)O_(8) Electrode In Lithium Sulfate-Water-Ethanol Electrolytes, An-Bao Yuan

Journal of Electrochemistry

The active material of LiV_(3)O_(8)prepared using low-temperature pre-reaction in solution followed by intermediate-temperature calcination at 450 ℃.The product was characterized by X-ray diffraction analysis and scanning electron microscope observation.The performance of LiV_(3)O_(8) electrode in neutral lithium sulfate-water-ethanol electrolytes was investigated using electrochemical methods.Galvanostatic charge/discharge results indicated that the specific capacity of LiV_(3)O_(8) electrode decreases with ethanol content increasing in electrolyte.The most appropriate water/ethanol volumetric ratio is 4 ∶1 in terms of conductivity of the electrolyte and stability of the electrode.AC impedance measurements demonstrated that the ohmic resistance of the electrolyte as well as the charge transfer resistance of the electrode/electrolyte …

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Degradation Of P-Nitrophenol Wastewater By Liquid Phase Catalyzed In Bipolar Liquid Bed Cell, Shi-Yuan Guo Aug 2006

Degradation Of P-Nitrophenol Wastewater By Liquid Phase Catalyzed In Bipolar Liquid Bed Cell, Shi-Yuan Guo

Journal of Electrochemistry

This investigation was performed to study the degradation of p-nitrophenol(PNP) in the bipolar liquid bed cell catalyzed by liquid phase.The hydrogen peroxide produced on cathodes with the ferrous generated Fenton's reagent to produce hydroxyl radicals which are very active toward organic compounds to strengthen bipolar liquid bed cell in disposing organic compounds.The effects of cell voltage,ferrous concentration and airflow on the COD and PNP removal efficiency were also studied.When pH=3.0,cell voltage is 30V,ferrous concentration is 500×10~(-6) and airflow is 0.4 m~(3)/h,higher removal efficiency of the COD and PNP are obtained.

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Investigation On The Resistance To Electrochemical Oxidation Of Carbon Nanotubes With Various Diameters, Yu-Yan Shao, Ge-Ping Yin, Yun-Zhi Gao, Peng-Fei Shi Aug 2006

Investigation On The Resistance To Electrochemical Oxidation Of Carbon Nanotubes With Various Diameters, Yu-Yan Shao, Ge-Ping Yin, Yun-Zhi Gao, Peng-Fei Shi

Journal of Electrochemistry

The resistance to electrochemical oxidation of multi-wall carbon nanotubes(CNT) with various diameters is investigated by applying a fixed potential of 1.2 V(RHE) for 120 h in 0.5 mol L~(-1) H_(2)SO_(4).The oxidation current of CNTs decreases with their diameters,but CNTs between 10~20 nm in diameter(D1020) shows the lowest oxidation current.XPS analysis shows that,after oxidation,the increase in surface oxygen for D1020 is the smallest,implying that the oxidation degree for D1020 is the lowest.The conclusion can be reached that CNTs between 10~20 nm in diameter are the most resistant to electrochemical oxidation.The difference in electrochemical stability of CNTs is attributed to the difference …

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Immobilization Of Cytochrome C On The Surface Of Single-Wall Carbon Nanotube And Its Direct Electron Transfer And Electrocatalysis, Ya-Jing Yin, Ya-Fen Lv, Ping Wu, Pan Du, Yan-Mao Shi, Chen-Xin Cai Aug 2006

Immobilization Of Cytochrome C On The Surface Of Single-Wall Carbon Nanotube And Its Direct Electron Transfer And Electrocatalysis, Ya-Jing Yin, Ya-Fen Lv, Ping Wu, Pan Du, Yan-Mao Shi, Chen-Xin Cai

Journal of Electrochemistry

Cytochrome c(Cyto c) was immobilized on the surface of the single-wall carbon nanotube(SWNT) by using the method of adsorption.Infrared spectroscopy indicated that the Cyto c remained in its original structure and did not undergo structural change after its immobilization on the SWNT.The direct electrochemistry of cyto c,which was adsorbed on the surface of the SWNT,was studied by cyclic voltammetry.The voltammetric results demonstrated that the SWNT had promoting effects on the direct electron transfer of Cyto c and also indicated that the immobilized Cyto c retained its bioelectrocatalytic activity to the reduction of H_(2)O_(2).This modified electrode might be used in development …

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