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Full-Text Articles in Chemistry

A Titanium-Supported Nanoporous Pd Electrocatalyst For Methanol Oxidation, Feng-Juan Niu, Qing-Feng Yi Feb 2011

A Titanium-Supported Nanoporous Pd Electrocatalyst For Methanol Oxidation, Feng-Juan Niu, Qing-Feng Yi

Journal of Electrochemistry

Titanium-supported nanoporous palladium electrode(nanoPd /Ti) was prepared by a hydrothermal process in the presence of the ligand EDTA and using formaldehyde as reducing agent.SEM images showed that the size of Pd particles was about 60 nm and the Pd particles were connected with each other to form a three-dimensional network structure.Cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS) were applied to evaluate the electrocatalytic activity of the nanoPd/Ti electrode towards methanol oxidation in alkaline solution.CV results showed that the nanoPd /Ti electrode presented high anodic peak densities and a low onset potential for methanol oxidation.Also nanoPd /Ti electrode showed excellent CO tolerance …


Electrocatalytic Oxidation Of Hydrazine At Rutin Carbon Nanotubes Modified Electrode, Hong-Fang Zhang, Qing-Lin Sheng, Jian-Bin Zheng Feb 2011

Electrocatalytic Oxidation Of Hydrazine At Rutin Carbon Nanotubes Modified Electrode, Hong-Fang Zhang, Qing-Lin Sheng, Jian-Bin Zheng

Journal of Electrochemistry

The electrochemical behavior and electrocatalytic oxidation of hydrazine on rutin multiwall carbon nanotubes modified glassy carbon electrode were studied by cyclic voltammetry.The experimental results indicated that the electrode exhibits good electrocatalytic activity to hydrazine at a reduced oxidation potential of 262 mV.The amperometric response of the modified electrode showed linear increase after successive addition of hydrazine in the concentration range of 2.5×10-6~1.0×10-4 mol·L-1 with a detection limit of 5×10-7 mol·L-1.


The Charge-Discharge Properties Of 40 Ah Aerospace Nickel Hydrogen Cell, Hai-Chang Zhang, Wen-Cheng Ming, Xue-Ying Ren, Hui-Juan Li, Hong-Min Fan, Li-Chao Li Feb 2011

The Charge-Discharge Properties Of 40 Ah Aerospace Nickel Hydrogen Cell, Hai-Chang Zhang, Wen-Cheng Ming, Xue-Ying Ren, Hui-Juan Li, Hong-Min Fan, Li-Chao Li

Journal of Electrochemistry

In present investigation,40 Ah nickel-hydrogen cell has been manufactured and its charge-discharge properties has been performed.The results indicate that the cell exhibited the best discharge capacity(50 Ah) when the test conditions were between 0~10 ℃,on the other hand,the cell accompanied with temperature being raised to 10 ℃ while the cell was subjected to discharge operating.The cell voltage decreased to -0.2 V and the cell temperature increased continuously during the over-discharge test.The cell voltage was first increased and then decreased,but the cell temperature was climbed rapidly while the cell was performed during the over-charge test.The 40 Ah nickel-hydrogen cell has excellent …


Novel Anion Exchange Membranes Base On Copolymer Of 2-(Diethylamino) Ethyl Methacrylate And Fluoro-Polyacrylate For Alkaline Direct Methanol Fuel Cells, Yan-Mei Zhang, Jun Fang, Ge Yan, Yong-Ze Zhuang Feb 2011

Novel Anion Exchange Membranes Base On Copolymer Of 2-(Diethylamino) Ethyl Methacrylate And Fluoro-Polyacrylate For Alkaline Direct Methanol Fuel Cells, Yan-Mei Zhang, Jun Fang, Ge Yan, Yong-Ze Zhuang

Journal of Electrochemistry

Anion exchange membrane fuel cells,which use anion exchange membranes as polyelectrolytes,have attracted more and more research interests recently.In this work,a series of hydroxyl-conducting anion-exchange membranes based on the copolymer of 2-(Diethylamino)ethyl methacrylate and fluoro-polyacrylate were prepared by radical polymerization,and their potential applications in alkaline fuel cells were assessed.It was shown that the ionic conductivity of the membranes reached 10-2 S·cm-1 at room temperature,while the methanol permeability was lower than 10-7 cm2·s-1.The maximum power density of fuel cell assembled with this membrane was achieved to be 43.2 mW·cm-2 at room temperature,indicating possible application …


Applications Of Raman Spectroscopy Technique In Lithium Ion Batteries, Liang Zhao, Yong-Sheng Hu, Hong Li, Zhao-Xiang Wang, Hong-Xing Xu, Xue-Jie Huang, Li-Quan Chen Feb 2011

Applications Of Raman Spectroscopy Technique In Lithium Ion Batteries, Liang Zhao, Yong-Sheng Hu, Hong Li, Zhao-Xiang Wang, Hong-Xing Xu, Xue-Jie Huang, Li-Quan Chen

Journal of Electrochemistry

The Raman spectroscopy has been widely used in the study of lithium ion batteries.In this short review,we gave some examples of the applications of Raman spectroscopy in the study of electrode materials including carbonaceous materials,spinel LiMxMn2-x O4,LiFePO4,as well as polymer electrolytes,room temperaturemolten salt electrolytes and the solid-electrolyte interphase layers.The advantages and disadvantages of the ex-situ and in-situ Raman spectrum techniques are discussed.Using new Raman techniques to investigate Li-ion batteries are suggested.


Electrochemical Double-Layer Capacitors Using Phenolic Resin-Based Carbon Fibers, Rong Xue, Jing-Wang Yan, Ying Tian, Bao-Lian Yi Feb 2011

Electrochemical Double-Layer Capacitors Using Phenolic Resin-Based Carbon Fibers, Rong Xue, Jing-Wang Yan, Ying Tian, Bao-Lian Yi

Journal of Electrochemistry

Phenolic resin-based activated carbon fiber(ACF) was prepared by KOH activation.The electrochemical properties of pulverized phenolic resin-based carbon fiber(P-ACF) were examined in 6 mol·L-1 KOH compared with that of the original ACF.P-ACF exhibited a better capacitive behavior and showed a larger specific capacitance(200 F·g-1) as well as a lower capacitance decrease at high current densities.The pore resistance for ion migration(Rp) in P-ACF was lower(2.96 Ω) than that in ACF(4.65 Ω).Pulverization increased the exposure of the cross section,lowered the contact resistance between the carbon fibers and decreased the pore resistance for ion migration.


Low-Temperature Performance Of Li-Ion Battery With Fluoroethylene Carbonate Electrolyte, Chun-Wei Yang, Feng Wu, Bo-Rong Wu, Yong-Huan Ren, Jing-Wen Yao Feb 2011

Low-Temperature Performance Of Li-Ion Battery With Fluoroethylene Carbonate Electrolyte, Chun-Wei Yang, Feng Wu, Bo-Rong Wu, Yong-Huan Ren, Jing-Wen Yao

Journal of Electrochemistry

The low temperature performance of electrolytes containing FEC including FEC+EMC, EC and PC, as well as the compatibility of electrolytes with LiFePO4 anode and with MCMB cathode were investigated.The electrolyte exhibits a high value of ionic conductivity at low temperature.The stability of cathode was enhanced by the formation of SEI film at 1.6 V as a result of FEC reaction. The infrared spectra showed that FEC can suppress decomposition of other solvents during SEI formation, and lower the resistance of SEI on MCMB cathode. The electrochemistry test indicates that Li-ion batteries with FEC electrolyte display high capacity at low …


Electrooxidation Of Methanol On Multilayer Films Of Polypyrrole-Platinum Electrode, Ling Zhang, Long-Zhen Zheng Feb 2011

Electrooxidation Of Methanol On Multilayer Films Of Polypyrrole-Platinum Electrode, Ling Zhang, Long-Zhen Zheng

Journal of Electrochemistry

Multilayer films of polypyrrole-platinum electrode were fabricated by cyclic voltammetric technique.Electro-oxidation of methanol on this electrode was investigated with the aid of cyclic voltammetry and chronoamperometry.Results demonstrated that the multilayer of polypyrrole-platinum electrode behaved better electrocatalytic performance for electro-oxidaton of methanol and better poison resistant.Furthermore,with the increase of deposited platinum loadings,the rate controlling step on electro-oxidation reaction of methanol was changed from CO oxidation to sorption-desorption of hydrogen.


Electrochemical Deposition Of Zinc Oxide Crystal Whiskers, Peng-Zeng Lu, Su Li, Jin-Qian Jia, Zhen-Hai Liang Feb 2011

Electrochemical Deposition Of Zinc Oxide Crystal Whiskers, Peng-Zeng Lu, Su Li, Jin-Qian Jia, Zhen-Hai Liang

Journal of Electrochemistry

Pine needle ZnO crystal whiskers were electrodeposited by anodization of zinc foil.The crystal whiskers were characterized by scanning electron microscopy(SEM) and X-ray diffraction(XRD) spectroscopy.The results show that the lengths and diameters of ZnO crystal whiskers are 200~300 nm and 20~50 nm,respectively,with the ratio of the length to diameter ranging from 10~15.The whiskers belong to wurtzite ZnO(JCPDS 36-1451) with good crystallinity and high purity.The crystalization behavior of ZnO was studied by cyclic voltammetry.The effects of the surface oxide layer at the zinc substrates and the [Zn(OH)4]2-concentration of the aqueous electrolyte on the formation of zinc oxide whiskers …


Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy, Wei Cao, Tao Huang, Xiao-Hong Nancy Xu, Hani E. Elsayed-Ali Jan 2011

Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy, Wei Cao, Tao Huang, Xiao-Hong Nancy Xu, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

Localized surface plasmon resonance (LSPR) of Ag nanoparticles (NPs) with different shapes and disk-shaped Ag NP pairs with varying interparticle distance is studied using dark-field optical microscopy and spectroscopy (DFOMS). Disk-, square-, and triangular-shaped Ag NPs were fabricated on indium tin oxide-coated glass substrates by electron beam lithography. The LSPR spectra collected from single Ag NPs within 5×5 arrays using DFOMS exhibited pronounced redshifts as the NP shape changed from disk to square and to triangular. The shape-dependent experimental LSPR spectra are in good agreement with simulations using the discrete dipole approximation model, although there are small deviations in the …


Precise Control Of Highly Ordered Arrays Of Nested Semiconductor/Metal Nanotubes, Diefeng Gu, Helmut Baumgart, Kandabara Tapily, Pragya Shrestha, Gon Namkoong, Xianyu Ao, Frank Müller Jan 2011

Precise Control Of Highly Ordered Arrays Of Nested Semiconductor/Metal Nanotubes, Diefeng Gu, Helmut Baumgart, Kandabara Tapily, Pragya Shrestha, Gon Namkoong, Xianyu Ao, Frank Müller

Electrical & Computer Engineering Faculty Publications

Lithographically defined microporous templates in conjunction with the atomic layer deposition (ALD) technique enable remarkable control of complex novel nested nanotube structures. So far three-dimensional control of physical process parameters has not been fully realized with high precision resolution, and requires optimization in order to achieve a wider range of potential applications. Furthermore, the combination of composite insulating oxide layers alternating with semiconducting layers and metals can provide various types of novel applications and eventually provide unique and advanced levels of multifunctional nanoscale devices. Semiconducting TiO2 nanotubes have potential applications in photovoltaic devices. The combination of nanostructured semiconducting materials …


Photoelectrochemical Properties Of N, S, And Cl Modified Nano Tio2 Thin Films, Hong Yun, Chang-Jian Lin, Jing Li, Rong-Gui Du Nov 2010

Photoelectrochemical Properties Of N, S, And Cl Modified Nano Tio2 Thin Films, Hong Yun, Chang-Jian Lin, Jing Li, Rong-Gui Du

Journal of Electrochemistry

The nitrogen(N),sulfur(S) and chlorine(Cl) modified nano TiO2 thin films were prepared by adding Ti(O-n-Bu)4 as the precursor into concentrated HNO3,H2SO4 and HCl Solutions,respectively,on different substrates in a sol-gel process.The photoelectrochemical performances of N,S and Cl modified nano TiO2 thin films have been studied by UV-vis(DRS),photocurrent curves,EIS and OCP-time curves.N-modified TiO2 nano films show better surface structure,which helps to improve the quantum efficiency of nano TiO2 thin films.


Hydrothermal Reduction Synthesis Of Lifepo4 And Its Electrochemical Performance, Hong-Li Zou, Guang-Hui Zhang, Pei-Kang Shen Nov 2010

Hydrothermal Reduction Synthesis Of Lifepo4 And Its Electrochemical Performance, Hong-Li Zou, Guang-Hui Zhang, Pei-Kang Shen

Journal of Electrochemistry

The cathode materials of LiFePO4 were prepared via a hydrothermal reduction method using FeCl3 as Fe source and iron as a reducing agent.The results showed that ferric salt could be reduced to ferrous salt completely under the hydrothermal condition and pure-phase LiFePO4 was obtained based on the test results of XRD and FTIR.Carbon-coated LiFePO4 was synthesized by pyrolysisng glucose at high temperature.The morphologies of pure LiFePO4 displayed cluster-like while the LiFePO4/C displayed sphere-like particles.The electrochemical test showed that the LiFePO4/C had good rate performance,while LiFePO4 delivered much lower discharge capacity.


Effects Of Solvents And Electrolyte Salts On The Electrochemical Reduction Of Oxygen In Non-Aqueous Electrolytes, Yan-Yan Tian, Wei Wu, Jun Gao, Yong Yang Nov 2010

Effects Of Solvents And Electrolyte Salts On The Electrochemical Reduction Of Oxygen In Non-Aqueous Electrolytes, Yan-Yan Tian, Wei Wu, Jun Gao, Yong Yang

Journal of Electrochemistry

The electrochemical reduction processes of oxygen in different non-aqueous solvents such as acetonitrile(MeCN),propylene carbonate(PC) and their mixtures were investigated by cyclic voltammetry method.The results indicated a one electron reduction of oxygen to O2-occured in these systems as a first step reduction,no matter whether in tetrabutylammonium hexafluorophosphate(TBAPF6)/MeCN or TBAPF6/PC electrolyte.However,the CV curves in 0.1 mol·L-1 TBAPF6/MeCN showed a couple of reversible redox peaks,indicating that the reduction process of oxygen was irreversible in the 0.1 mol·L-1 TBAPF6/PC electrolyte.In the PC-based electrolyte,the reduction current peak reduced largely and the oxidation peak …


Electrodeposition Of Lead Dioxide From Dluoroborate Solutions, Chun-Mei Kong, Yong-Ming Tang, Wen-Zhong Yang, Xiao-Yuan Yang Nov 2010

Electrodeposition Of Lead Dioxide From Dluoroborate Solutions, Chun-Mei Kong, Yong-Ming Tang, Wen-Zhong Yang, Xiao-Yuan Yang

Journal of Electrochemistry

The PbO2 anodes were prepared on platinum from fluoroborate media and its doped solutions by electrodeposition technique.Elecchemical and pysicochemical properties of these PbO2 films were studied by cyclic voltammetry methods,XRD and SEM.The results showed that the presence of BF4-increased PbO2 electrodeposition rate;the prepared lead dioxide consisted of β-PbO2;the preferential orientation of crystals and surface morphology were affected a lot by doping F-and Fe3+.The FB/F-Fe-PbO2 electrode exhibited regular-shaped layers with compact morphology.Furthermore,increasing current density also change the preferential orientation of PbO2 crystals.


The Sol-Gel Synthesis And Electrochemical Performance Of Li3V2(Po4)3/C Cathode Material For Lithium Ion Battery, Li-Ying Liu, Lian Chen, Hai-Yan Zhang, Yu-Chun Zhai Nov 2010

The Sol-Gel Synthesis And Electrochemical Performance Of Li3V2(Po4)3/C Cathode Material For Lithium Ion Battery, Li-Ying Liu, Lian Chen, Hai-Yan Zhang, Yu-Chun Zhai

Journal of Electrochemistry

Li3V2(PO4)3/C was synthesized by sol-gel method with citric acid as chelate and C sources. Physical and electrochemical performances of as-prepared materials were characterized through XRD, SEM and galvanostatic charge-discharge tests,etc. The results showed that products produced by calcining at 800 ℃ for 12 h had a single phase crystal structure and relatively small particle sizes with uniform distribution. At 0.1 C, 0.5 C and 1 C, the initial specific discharge capacities were 153.0, 143.1 and 130.6 mAh·g-1, respectively, and capacity efficiencies were 93.1%, 85.4% and 77.3% after 50 cycles, respectively. …


Research On Nafion/Sio2 Composite Membrane In All Vanadium Redox Flow Battery, Dong-Dong Liu, Mao-Cai Lin, Tao Guan, Qing-Chun Yu Nov 2010

Research On Nafion/Sio2 Composite Membrane In All Vanadium Redox Flow Battery, Dong-Dong Liu, Mao-Cai Lin, Tao Guan, Qing-Chun Yu

Journal of Electrochemistry

The Nafion117/SiO2 composite membrane was prepared by sol-gel method.The results showed that,during composite membrane preparation process,the ratio of MeOH and TEOS did not affect the penetration rate of VO2+ basically,however,the lowest permeability of 427×10-9cm2/s in the membrane was achieved while hydrolysis time was 10 min and natural drying for 24 h after hydrolysis,which reduced by 52 times than that in Nafion117 membrane.The SEM tests proved that SiO2 grains grew bigger in the composite membrane during the natural drying,and most of the holes in Nafion117 were filled.Single cell test showed the battery power efficiency was improved …


Electrooxidation Of Carbon Monoxide On Pd Thin Film-Coated Au Electrodes: Film Thickness Dependence, Yuqing Yang, Shouzhong Zou Aug 2010

Electrooxidation Of Carbon Monoxide On Pd Thin Film-Coated Au Electrodes: Film Thickness Dependence, Yuqing Yang, Shouzhong Zou

Journal of Electrochemistry

The adsorption and electrooxidation of CO on Pd-coated Au electrodes were studied by cyclic voltammetry and surface-enhanced Raman spectroscopy (SERS) . It is found that CO oxidation activity is film thickness dependent. Cyclic voltammograms (CVs) showed that CO oxidation peak potential shifted positively with the increase of the Pd thickness. SERS showed a redshift of the C—O stretching frequency with increasing Pd film thickness. These observations were explained by the dband theory. The strain effect strengthens CO adsorption and stabilizes adsorbed CO,while the ligand effect weakens CO adsorption and eases its oxidation. The ligand effect overpowers the strain effect.


In Situ Surface-Enhanced Raman Scattering Spectroscopic Study Of Sulfur Adsorption On Polycrystalline Platinum Electrode Surface, Bolian Xu, In-Su Park, Ying Li, De-Jun Chen, Yuye J. Tong Aug 2010

In Situ Surface-Enhanced Raman Scattering Spectroscopic Study Of Sulfur Adsorption On Polycrystalline Platinum Electrode Surface, Bolian Xu, In-Su Park, Ying Li, De-Jun Chen, Yuye J. Tong

Journal of Electrochemistry

The paper reports the first in situ surface enhanced Raman scattering (SERS) spectroelectrochemistry study of sulfur adsorption and electro-oxidation on highly roughened polycrystalline Pt surface in both acidic and basic supporting electrolytes. The SERS spectra were taken at a constant electrode potential after accumulative electro-oxidation CVs of the Pt electrode with pre-adsorbed sulfur species and at different electrode potentials that were varied stepwise of the Pt electrode immersed in sulfur-containing electrolytes without pre-adsorbed sulfur species. In both cases,a dominant vibrational band at 299 cm-1 in acidic electrolyte but at 310 cm-1 in basic electrolyte was observed,which was assigned …


Studies Of Oxidation Processes Of Adsorbed And Solution Co On Pt(110) Electrode By Cyclic Voltammetry And In Situ Ftirs, Li Tian, Jun-Tao Li, Jin-Yu Ye, Chun-Hua Zhen, Shi-Gang Sun Aug 2010

Studies Of Oxidation Processes Of Adsorbed And Solution Co On Pt(110) Electrode By Cyclic Voltammetry And In Situ Ftirs, Li Tian, Jun-Tao Li, Jin-Yu Ye, Chun-Hua Zhen, Shi-Gang Sun

Journal of Electrochemistry

The oxidation processes of adsorbed CO (COad) and solution phase CO (COsol) on Pt(110) electrode were investigated by cyclic voltammetry and in-situ FTIR spectroscopy. It has revealed that in comparison with COad on Pt(110) in a CO-free solution,the oxidation current peak of COsol in a CO-saturated solution is positively shifted ca. 168 mV,and the peak current density has been increased by 6. 70 times. Linear adsorbed CO (COL) is determined by in-situ FTIR spectroscopy as the main species,which is uniformly distributed on Pt (110) surface. In a CO-free solution,the onset potential of COL is measured by in-situ FTIRS ca. 0. …


An In Situ Fourier Transform Infrared Spectroelectrochemical Study On Alcohols Electrocatalytic Oxidation At Pd Electrode In Acidic Solution, Hai-Ping Huang, Lian-Qin Wang, Pei-Kang Shen Aug 2010

An In Situ Fourier Transform Infrared Spectroelectrochemical Study On Alcohols Electrocatalytic Oxidation At Pd Electrode In Acidic Solution, Hai-Ping Huang, Lian-Qin Wang, Pei-Kang Shen

Journal of Electrochemistry

The methanol and ethylene glycol electrooxidation on palladium electrode in acidic solution has been investigated by cyclic voltammetry and in situ Fourier transform infrared spectroelectrochemistry. It shows that the oxidation of methanol and ethylene glycol at Pd electrode cannot proceed until over 1.5 V in acidic and neutral media. The overpotential decreases and the peak current density increases with the reduction in pH values. The formation of the oxygen-containing species significantly affects the alcohol oxidation on Pd electrode. The in situ FTIR spectroscopic measurements show that the oxidation products of ethylene glycol on Pd electrode are CO2 and oxalic …


Comparative Study Of Nanoporous Pt, Ptru And Ptruir Catalysts Using Electrochemical Ftir Spectroscopy, M. Amussen Robert, Holt-Hindle Peter, Nigro Samantha, Aicheng Chen Aug 2010

Comparative Study Of Nanoporous Pt, Ptru And Ptruir Catalysts Using Electrochemical Ftir Spectroscopy, M. Amussen Robert, Holt-Hindle Peter, Nigro Samantha, Aicheng Chen

Journal of Electrochemistry

In recent years much effort has been put towards developing efficient Pt-based electrocatalysts for applications in fuel cells. With the rising cost of precious metals such as Pt,the need to enhance the activity and to decrease the load of catalysts is prominent. Herein we report on the synthesis and comparative study of nanoporous Pt,PtRu and PtRuIr electrocatalysts. The nanoporous electrodes were fabricated using a hydrothermal method and characterized by scanning electron microscopy (SEM) ,energy dispersive spectroscopy (EDS) ,X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) . The electrocatalytic activity of the fabricated nanopo- rous materials was evaluated using both CO …


Solid State Nmr Studies Of Lithium Manganese Silicate As Positive Electrode Materials For Li-Ion Batteries, Hu Cheng, Zi-Geng Liu, Yi-Xiao Li, Zhong Chen, Yong Yang Aug 2010

Solid State Nmr Studies Of Lithium Manganese Silicate As Positive Electrode Materials For Li-Ion Batteries, Hu Cheng, Zi-Geng Liu, Yi-Xiao Li, Zhong Chen, Yong Yang

Journal of Electrochemistry

The Li2MnSiO4 cathode material for lithium ion batteries was synthesized by sol-gel assisted hydrothermal method. XRD,FTIR and SS-NMR were used to study the phase,structure and morphology of obtained samples. Electrochemical performance of cathode material was tested. The results show that the main phase of sample prepared was Li2MnSiO4,whereas a small amount of impurities (Li2CO3) were existed. The Li2MnSiO4 cathode material gave an initial discharging capacity of about 190 mAh·g -1. But this capacity faded rapidly during the cycling process due to the decomposition of Li …


Optimization Of Membrane Electrode Assembly In Air-Breathing Direct Methanol Fuel Cell, Liang Ma, Wei-Wei Cai, Jing Zhang, Liang Liang, Jian-Hui Liao, Chang-Peng Liu, Wei Xing May 2010

Optimization Of Membrane Electrode Assembly In Air-Breathing Direct Methanol Fuel Cell, Liang Ma, Wei-Wei Cai, Jing Zhang, Liang Liang, Jian-Hui Liao, Chang-Peng Liu, Wei Xing

Journal of Electrochemistry

The structure and performance of MEA were optimized by tailoring the catalyst layer,cathodic microporous layer (MPL) ,anodic MPL and membrane,with the considerations of unique characteristics of airbreathing direct methanol fuel cell (DMFC) such as methanol crossover and cathode flooding. It was found that high catalyst loading could suppress the methanol crossover effectively,but too high catalyst loading can lead to high mass transport resistance. Hydrophobic anodic MPL with 30% (by mass) PTFE could facilitate the CO2 bubble detachment,which decreased the methanol concentration gradient and suppressed the methanol crossover accordingly. When Nafion 115 was used as membrane,methanol crossover was severe,while Nafion …


A High Performance Sulfur/Carbon Xerogel Composite In Lithium Sulfur Battery Application, Chong Wang, Jia-Jia Chen, Qiu-Jie She, Qian Zhang, Yi-Ning Shi, Ming-Sen Zheng, Quan-Feng Dong May 2010

A High Performance Sulfur/Carbon Xerogel Composite In Lithium Sulfur Battery Application, Chong Wang, Jia-Jia Chen, Qiu-Jie She, Qian Zhang, Yi-Ning Shi, Ming-Sen Zheng, Quan-Feng Dong

Journal of Electrochemistry

Sulfur/carbon composite was synthesized by the thermal method with the carbon xerogel as the conductive framework. The property of composite was characterd by XRD and SEM. It shown that the composite with the particle size below 10 μm had the same morphology as the carbon xerogel and the sulfur was absorbed in the pores in non-crystalline. The discharge capacity of the composites were 1311 mAh/g and 1107. 1 mAh/g at 0. 1C and 0. 2 C rates,respetively. And a retention capacity was about 800 mAh/g after 30 cylcyes.


Nano/Micro-Structured Electrode Materials For Lithium-Ion Batteries, Yu-Guo Guo, Zhong-Li Wang, Xing-Long Wu, Wei-Ming Zhang, Li-Jun Wan May 2010

Nano/Micro-Structured Electrode Materials For Lithium-Ion Batteries, Yu-Guo Guo, Zhong-Li Wang, Xing-Long Wu, Wei-Ming Zhang, Li-Jun Wan

Journal of Electrochemistry

Nanostructured materials are currently of interest as high performance anodes and cathodes for rechargeable lithium-ion batteries because of their novel nano-size effects and significantly enhanced kinetics. This review paper describes some recent developments in this field,addressing the size effects,morphology effects,as well as the functions of carbon coating layers toward lithium storage. Several"kinetically stabilized"nano/microstructured electrode materials and high-rate electrode materials with mixed-conducting networks based on the work of the authors are highlighted for illustration.


Electrocatalytic Oxidation Of Hcooh At Au(Core)-Pd(Shell)-Pt(Cluster) Nanocubes, Qing-Ning Jiang, Huan Li, Ning Yang, Ping-Ping Fang, Feng-Ru Fan, Zhong-Qun Tian May 2010

Electrocatalytic Oxidation Of Hcooh At Au(Core)-Pd(Shell)-Pt(Cluster) Nanocubes, Qing-Ning Jiang, Huan Li, Ning Yang, Ping-Ping Fang, Feng-Ru Fan, Zhong-Qun Tian

Journal of Electrochemistry

Gold nanocubes were synthesized by a two-step seed-mediated growth method. The Aucore-Pdshell and Aucore-Pdshell-Ptcluster nanocubes with controllable shell thickness of Pd and cluster coverage of Pt were synthesized by simply changing the amount ratio of H2PdCl4 or H2PtCl6. The samples were characterized by scanning electron microscope (SEM) , transmission electron microscopc (TEM) and cyclic voltammetry (CV). CV was then used to make a systematic study on the dependence of the electrocatalytic properties on the shell thickness of Aucore-Pdshell and Pt coverage of Aucore-Pd …


High-Rate Cyclic Properties Of Hollow Carbon Hemisphere As Anode Materials For Lithium Ion Batteries, Guang-Hui Zhang, Zao-Xue Yan, Hong-Li Zou, Pei-Kang Shen May 2010

High-Rate Cyclic Properties Of Hollow Carbon Hemisphere As Anode Materials For Lithium Ion Batteries, Guang-Hui Zhang, Zao-Xue Yan, Hong-Li Zou, Pei-Kang Shen

Journal of Electrochemistry

High surface area hollow carbon hemispheres (HCHs) covered with hard carbon layers have been synthesized by using polystyrene spheres (PSs) as templates under hydrothermal method combined with the intermittent microwave heating (IMH) method. The morphologies of the materials are characterized by SEM and TEM. The electrochemical properties of the HCHs are tested. Comparing with graphite and mesocarbon microbeads (MCMB) ,the HCHs show higher capacity and excellent cyclic life performance.


Research On Electrochemical Performance Of Lithium-Ion Battery Cathode Material Lini(1/3)Co(1/3)Mn(1/3)O2 In Aqueous Lino3 Solution, Jun Zheng, Xin Jia, Chong Wang, Ming-Sen Zheng, Quan-Feng Dong May 2010

Research On Electrochemical Performance Of Lithium-Ion Battery Cathode Material Lini(1/3)Co(1/3)Mn(1/3)O2 In Aqueous Lino3 Solution, Jun Zheng, Xin Jia, Chong Wang, Ming-Sen Zheng, Quan-Feng Dong

Journal of Electrochemistry

The cathode material of LiNi1/3Co1/3Mn1/3O2 synthesized by sol-gel method shows excellent high rate performance, and high output power density during discharge process. A well-ordered layered α-NaFeO2 structure was confirmed by XRD and a primary particle size of about 500 nm was indicated by SEM. Galvanostatic charge-discharge test indicates that LiNi1/3Co1/3Mn1/3O2 in 2 mol·L-1 LiNO3 aqueous solution with pH 12 reached a ca-pacity of 147 mAh/g while charged and discharged at 2C. The capacities were 64, 33, 16 mAh/g with 80C (14.4 A/g), 150C …


Fabrication Of Electrochemically Activated Glassy Carbon/Bismuth Film Electrodes For Sensitive Analysis Of Pb(2+) And Cd(2+), Kang Shi, Wen-Jing Wang, Kun Hu May 2010

Fabrication Of Electrochemically Activated Glassy Carbon/Bismuth Film Electrodes For Sensitive Analysis Of Pb(2+) And Cd(2+), Kang Shi, Wen-Jing Wang, Kun Hu

Journal of Electrochemistry

The application of electrochemically activated glassy carbon (GC) in the in-situ preparing of bismuth film electrodes (BiFEs) to analyze Pb2 + and Cd2 + was investigated. The glassy carbon electrodes were electrochemically activated by either potentiostic or cyclic polarization in 1 mol·L-1 NaOH solution. Experimental results show that employment of HCl solution as the analytical solution not only can reproducibly renew the electrochemically activated GC electrode surface with an electrochemical clear procedure, but also can greatly enhance the sensitivity of BiFes method for analysis of Pb2 + and Cd2 +. The test range thus …