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Full-Text Articles in Engineering Science and Materials

Electrocatalytic Oxidation Degradation Kinetics Of Oxalic Acid In A Cylindrical Electrochemical Reactor With Ti/Iro2-Ta2O5 Anode, Jing Su, Hai-Bo Lin, Hong Xu, Wei-Min Huang, Ya-Peng He Aug 2013

Electrocatalytic Oxidation Degradation Kinetics Of Oxalic Acid In A Cylindrical Electrochemical Reactor With Ti/Iro2-Ta2O5 Anode, Jing Su, Hai-Bo Lin, Hong Xu, Wei-Min Huang, Ya-Peng He

Journal of Electrochemistry

The electrocatalytic oxidation degradation kinetics of oxalic acid in a cylindrical electrochemical reactor with Ti/IrO2-Ta2O5 as an anode was studied. The relation between instantaneous current efficiency and organic concentration in bulk was established based on the two paths for direct electrochemical oxidations, and the theoretical model was verified by experiments. The experimental resultswere reasonably consistent with the established kinetic model. Furthermore, the competition between the two paths was explored with the modelparameter analysis.


Graphene Quantum Dots Enhanced Electrochemical Performance Of Polypyrrole As Supercapacitor Electrode, Kun Wu, Si-Zhe Xu, Xue-Jiao Zhou, Hai-Xia Wu Aug 2013

Graphene Quantum Dots Enhanced Electrochemical Performance Of Polypyrrole As Supercapacitor Electrode, Kun Wu, Si-Zhe Xu, Xue-Jiao Zhou, Hai-Xia Wu

Journal of Electrochemistry

With an objective to develop electrode materials with high specific capacitance and good stability, a completely new nanocomposite of Polypyrrole (PPY) and graphene quantum dots (GQD) was successfully obtained through in-situ polymerization of pyrrole in the presence of GQD suspension. The obtained composites with different mass ratios were characterized by X-Ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). GQD enhanced electrochemical performance of PPY and, as supercapacitor electrodes, the PPY/GQD composites with the mass ratio of PPY to GQD at 50:1 showed a competitive specific capacitance of 485 F·g-1 at a scan rate of …


Influence Of Pretreatment On Electrocatalytic Property For Methanol Oxidation Of Ptru/Wc, Xiao-Ling Lang, Mei-Qin Shi, Ye-Kun Jiang, Chun-An Ma Aug 2013

Influence Of Pretreatment On Electrocatalytic Property For Methanol Oxidation Of Ptru/Wc, Xiao-Ling Lang, Mei-Qin Shi, Ye-Kun Jiang, Chun-An Ma

Journal of Electrochemistry

The surface of tungsten carbide (WC) was treated by potassium hydroxide (KOH) at different pH values for different time. The PtRu/WC composite was prepared by microwave-assisted polyol method. The phase structure of PtRu/WC composites were characterized by XRD. The electrocatalytic activity was tested by cyclic voltammetry and chronoamperometry. The results indicated that with different pH treatments WC became more readily supported on PtRu. When treating WC in KOH at pH = 14, PtRu exhibited the best degree of crystallinity on WC surface, leading to the highest electrocatalytic activity of PtRu/WC. Moreover, the optimized activity of PtRu/WC towards methanol oxidation was …


Performance Of The Electro-Oxidation And Electro-Fenton Processes With A Bdd Anode For The Treatment Of Low Contents Of Pharmaceuticals In A Real Water Matrix, Sirs Ignasi, Antonio Garrido Jos, Brillas Enric Aug 2013

Performance Of The Electro-Oxidation And Electro-Fenton Processes With A Bdd Anode For The Treatment Of Low Contents Of Pharmaceuticals In A Real Water Matrix, Sirs Ignasi, Antonio Garrido Jos, Brillas Enric

Journal of Electrochemistry

Here, we report the performance of electro-oxidation and electro-Fenton with a boron-doped diamond (BDD) anode for the treatment of single and multicomponent solutions containing small amounts of pharmaceutical residues (i.e., 1 mg·L-1 paracetamol and/or 1 mg·L-1 salicylic acid) spiked into a real water matrix at pH 3.0. Electro-oxidation was performed in a BDD/Pt cell, whereas electro-Fenton was carried out in a BDD/air-diffusion cell to electrogenerate H2O2 at the cathode, always operating at constant current density. It was found that the decay of both pharmaceuticals by electro-oxidation was more rapid in the real water matrix than …


Synthesis And Electrochemical Properties Of Li(Ni0.5Co0.2Mn0.3)1-2xTiXNbXO2, Yong Tang, Qin-Lin Liao, Xiang-An Guo Aug 2013

Synthesis And Electrochemical Properties Of Li(Ni0.5Co0.2Mn0.3)1-2xTiXNbXO2, Yong Tang, Qin-Lin Liao, Xiang-An Guo

Journal of Electrochemistry

The cathode-active materials of layered Li(Ni0.5Co0.2Mn0.3)1-2xTixNbxO2(x=0, 0.002, 0.005, 0.01, 0.02)composites were synthesized by the thermal treatment of the coprecipitated precursor at 900 oC in air. The effects of Ti-Nb co-dopants on the structural and electrochemical properties of Li(Ni0.5Co0.2Mn0.3)O2 were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical experiments. The results show that the small amounts of Ti-Nb co-dopants in Li(Ni0.5Co0.2Mn0.3)O2significantly decreased the degree of cation mixing in …


Preparation And Electrochemical Performance Of Hollow Carbon Spheres/Sulfur Composite, Jun Zang, Hang Qian, Er-Man Zeng, Juan-Ni Fu, Ming-Sen Zheng, Quan-Feng Dong Jun 2013

Preparation And Electrochemical Performance Of Hollow Carbon Spheres/Sulfur Composite, Jun Zang, Hang Qian, Er-Man Zeng, Juan-Ni Fu, Ming-Sen Zheng, Quan-Feng Dong

Journal of Electrochemistry

Hollow carbon spheres were prepared by the PMMA template. Hollow carbon spheres/sulfur composite was made from sulfur and hollow carbon spheres as a conducting framework. The results of SEM and TEM showed that sulfur was uniformly filled in both of the shell and hollow core of hollow carbon spheres. The electrochemical performance of hollow carbon spheres/sulfur composite was characterized by the charge/discharge method. The results showed the excellent rate and cycle performance of hollow carbon spheres/sulfur composite. The reversible capacities of hollow carbon spheres/sulfur composite are 1145 mAh·g-1, 824 mAh·g-1, 702 mAh·g-1, 586 mAh·g …


Influence Of Electrode Hydrophobicity On Performance Of Alkaline Polymer Electrolyte Fuel Cells, Li-Sheng Tan, Jing Pan, Yao Li, Lin Zhuang, Jun-Tao Lu Jun 2013

Influence Of Electrode Hydrophobicity On Performance Of Alkaline Polymer Electrolyte Fuel Cells, Li-Sheng Tan, Jing Pan, Yao Li, Lin Zhuang, Jun-Tao Lu

Journal of Electrochemistry

In the present work, we study the influence of the electrode hydrophobicity on the performance of alkaline polymer electrolyte fuel cells (APEFCs). QAPS or xQAPS is employed as the membrane and the ionomer, while PTFE is used as a hydrophobic additive in order to adjust the electrode hydrophobicity. We find that enhancing the hydrophobicity of anode can promote the performance of APEFCs, while a moderate hydrophobicity of cathode is required to achieve optimal performance. By using xQAPS as the electrolyte and adding some PTFE in the anode, a peak power density of 132 mW·cm-2 can be obtained …


The Effect Of Precursors On Performance Of Lini0.5Co0.2Mn0.3O2 Cathode Material, Dong-Ge Hu, Zhang-Zhi Wang, Jia-Li Liu, Tao Huang, Ai-Shui Yu Jun 2013

The Effect Of Precursors On Performance Of Lini0.5Co0.2Mn0.3O2 Cathode Material, Dong-Ge Hu, Zhang-Zhi Wang, Jia-Li Liu, Tao Huang, Ai-Shui Yu

Journal of Electrochemistry

Commercial LiNi0.5Co0.2Mn0.3O2 material is generally prepared by a combination of co-precipitation and solid state reaction method. The particle size distribution and morphology of Ni0.5Co0.2Mn0.3(OH)2 precursor have a great impact on the electrochemical performance of LiNi0.5Co0.2Mn0.3O2. In this work, the crystal structure and surface morphology of LiNi0.5Co0.2Mn0.3O2 prepared by three different precursors were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Particle size distribution, tap density and electrochemical performance were …


Preparation And Characterization Of A Novel Composite Electrolyte Ceria-Sulfate For Intermediate Temperature Solid Oxide Fuel Cells, Ze Tong, Yi-Mei Yin, Jie-Wei Yin, Zi-Feng Ma Jun 2013

Preparation And Characterization Of A Novel Composite Electrolyte Ceria-Sulfate For Intermediate Temperature Solid Oxide Fuel Cells, Ze Tong, Yi-Mei Yin, Jie-Wei Yin, Zi-Feng Ma

Journal of Electrochemistry

A novel composite electrolyte SDC-(Li/Na)2SO4 was prepared for intermediate temperature solid oxide fuel cells (ITSOFC). The phase structure and cross-sectional morphology were examined by XRD and SEM, respectively, and the ionic conductivity was investigated by AC impedance in a temperature range of 400 oC ~ 700 oC in air. It was found that the composite electrolyte was composed of two phases: crystal SDC and amorphous (Li/Na)2SO4. The conductivity of the composite electrolyte was significantly larger than that of SDC at intermediate temperatures (550 oC ~ 700 oC) and increased …


Progress Of Lithium Rich Cathode Materials For Li-Ion Batteries, Jie Zhang, Wang Jiu-Lin, Yang Jun Jun 2013

Progress Of Lithium Rich Cathode Materials For Li-Ion Batteries, Jie Zhang, Wang Jiu-Lin, Yang Jun

Journal of Electrochemistry

Lithium rich materials xLi2MnO3·(1-x)LiMO2 (0<x<1, M=Mn, Co, Ni) become a hot topic because of their high capacities exceeding 250 mAh·g-1 and low cost. However, the large irreversible capacity during the first cycle, low rate capability and structure collapse during cycling remain impediments in developing these cathodes for applications. The structure analyses and charge/discharge mechanisms for lithium rich materials are currently main research contents. Although whether the lithium rich materials are solid solutions or composite is still controversial, oxygen release mechanism on the first charge 4.5 V plateau of lithium rich materials has come to consistency. Several modifications, such as bulk doping, surface coating and microstructure …


Polypyrrole-Transition Metal-Oxygen Coordination Complexes As High Performance Lithium Storage Material, Ya Mao, Qingyu Kong, Bingkun Guo, Zhaoxiang Wang, Liquan Chen Jun 2013

Polypyrrole-Transition Metal-Oxygen Coordination Complexes As High Performance Lithium Storage Material, Ya Mao, Qingyu Kong, Bingkun Guo, Zhaoxiang Wang, Liquan Chen

Journal of Electrochemistry

No abstract provided.


Electrochemical Performance Of Al-Doped Spinel Limn2O4 Cathode Material For Li-Ion Batteries, Yong-Long Wang, Wen-Ge Wang, Qian Zhang, Xin Wang, Jian-Sheng Cao, Shi-Hai Ye Jun 2013

Electrochemical Performance Of Al-Doped Spinel Limn2O4 Cathode Material For Li-Ion Batteries, Yong-Long Wang, Wen-Ge Wang, Qian Zhang, Xin Wang, Jian-Sheng Cao, Shi-Hai Ye

Journal of Electrochemistry

Spinel LiMn2O4, a cathode material for Li-ion batteries, is featured as good high-rate performance, low cost and environmental friendly. The pristine and Al-doped LiMn2O4 samples were prepared by sol-gel method. The structure and micromorphology of the as-prepared samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results demonstrated that the as-prepared LiMn2O4 samples had a typical cubic spinel structure and were composed of sphere-like particles with a diameter range of 300 ~ 500 nm. Galvanostatic charge-discharge tests showed that the LiMn2O4 samples doped …


Effect Of Ethyl Propionate On Low-Temperature Performance Of Lifepo4-Based Li-Ion Battery, Xiao-Ping Li, Lian-Sheng Hao, Wei-Shan Li, Meng-Qing Xu, Li-Dan Xing Jun 2013

Effect Of Ethyl Propionate On Low-Temperature Performance Of Lifepo4-Based Li-Ion Battery, Xiao-Ping Li, Lian-Sheng Hao, Wei-Shan Li, Meng-Qing Xu, Li-Dan Xing

Journal of Electrochemistry

A linear carboxylic, ester ethyl propionate (EP), was used as the co-solvent of carbonates, ethylene carbonate (EC), ethyl-methyl carbonate (EMC) and dimethyl carbonate (DMC), and its effect on low-temperature performance of LiFePO4-based Li-ion battery was studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge test. The application of EP enhances the ionic conductivity of the electrolyte, improves the compatibility of the electrolyte with both LiFePO4 and graphite materials, and thus improves the low-temperature performance of LiFePO4-based Li-ion battery. The Li-ion battery using the optimized electrolyte of 1 mol·L-1 LiPF6/EC:EMC:DMC:EP …


Electrocatalytic Mechanism And Porous Electrode Mass Transfer Process In Membrane Electrode Assembly For Direct Methanol Fuel Cells, Xin-Dong Wang, Yi-Tuo Wang, Gui-Cheng Liu, Meng Wang, Zhe Tian Jun 2013

Electrocatalytic Mechanism And Porous Electrode Mass Transfer Process In Membrane Electrode Assembly For Direct Methanol Fuel Cells, Xin-Dong Wang, Yi-Tuo Wang, Gui-Cheng Liu, Meng Wang, Zhe Tian

Journal of Electrochemistry

Direct methanol fuel cell (DMFC) is considered to be a promising commercial energy conversion device for portable electronics due to its many advantages. In order to improve the performance of DMFC, many companies and research institutes have been launching the deep research and obtaining a lot of conspicuous achievements. In this paper, the electrocatalytic mechanism and porous electrode mass transfer process in membrane electrode assembly (MEA) are analyzed. In addition, combined with the preparation process of MEA, multilayer ordered structures and internal transfer process of the cell, recent progresses of MEA in DMFC are discussed.


Multifunctional Corrosion Inhibition Behavior Of Zn-Al Calcined Layered Double Hydroxides For Steel Rebar In Nacl Solution, Xiao-Juan Zhang, Jing-Jing Wang, Shi-Gang Dong, Chang-Jian Lin Jun 2013

Multifunctional Corrosion Inhibition Behavior Of Zn-Al Calcined Layered Double Hydroxides For Steel Rebar In Nacl Solution, Xiao-Juan Zhang, Jing-Jing Wang, Shi-Gang Dong, Chang-Jian Lin

Journal of Electrochemistry

The Zn-Al layered double hydroxides (Zn-Al LDHs) and calcined products (Zn-Al CLDHs) were synthesized successfully under a routine air atmosphere. The results showed that both Zn-Al LDHs and Zn-Al CLDHs had obvious flake structures. The corrosion inhibition of Zn-Al CLDHs for steel rebar in NaCl solution was studied by electrochemical techniques. It was found that the corrosion rate of steel rebar decreased significantly after the steel rebar was treated by Zn-Al CLDHs in NaCl solution for 3 h. It was indicated that Zn-Al CLDHs could absorb Cl- and release OH- during their reconstruction process, which provided dual protection …


Influences Of The Cinnamic Acid On Zinc Electrodeposition At Glassy-Carbon Electrode, Kai Li, Shen Chen, Shen-Na Liu, Bi-Sang Chen, Heng Lin, Guo-Liang Chen, Qing-Xiang Wang Jun 2013

Influences Of The Cinnamic Acid On Zinc Electrodeposition At Glassy-Carbon Electrode, Kai Li, Shen Chen, Shen-Na Liu, Bi-Sang Chen, Heng Lin, Guo-Liang Chen, Qing-Xiang Wang

Journal of Electrochemistry

The influences of cinnamic acid (CIN) on the mechanism of Zn deposition and nucleation kinetics onto glassy-carbon electrode were studied by cyclic voltammetry (CV) and chronoamperometry (CA). The results revealed that the zinc reduction took place via Zn2+ + 2e → Zn in the presence of CIN, but the kinetics of zinc deposition was changed and the formation rate of zinc nuclei was accelerated. In the absence of CIN, the mechanism of zinc nucleation followed the 3D-instantaneous diffusion-controlled nucleation, while the 3D-progressive diffusion-controlled nucleation in the presence of CIN. The addition of CIN reduced the nucleation rate, but increased …


Fabrication And Performance Of Lani0.6Fe0.4O3-δ Cathode Modified By Coating With Gd0.2Ce0.8O2 For Intermediate Temperature Solid Oxide Fuel Cell, Rui-Xuan Ren, Bo Huang, Xin-Jian Zhu, Yi-Xing Hu, Xiao-Yi Ding, Zong-Yao Liu, Ye-Bin Liu Jun 2013

Fabrication And Performance Of Lani0.6Fe0.4O3-δ Cathode Modified By Coating With Gd0.2Ce0.8O2 For Intermediate Temperature Solid Oxide Fuel Cell, Rui-Xuan Ren, Bo Huang, Xin-Jian Zhu, Yi-Xing Hu, Xiao-Yi Ding, Zong-Yao Liu, Ye-Bin Liu

Journal of Electrochemistry

The symmetric cell of LaNi0.6Fe0.4O3-δ/Sc0.1Zr0.9O1.95/LaNi0.6Fe0.4O 3-δ was fabricated with screen printing method. A LaNi0.6Fe0.4O3-δ (LNF) cathode was modified by coating with nano-sized gadolinium-doped ceria (GDC, Gd0.2Ce0.8O2) prepared using a simple combustion process within the pores of the cathode. According to the electrochemical impedance spectra (EIS), the polarization resistance of the pure LNF was 0.70 W·cm2 at 750 ºC, while 0.13 W·cm2 for the 21.3% GDC (by mass)-coated LNF …


A Comparative Study Of Ce3+/Ce4+ Redox Couple On Pt Electrode In Sulfuric Acid And Methanesulfonic Acid, Zhao-Hua Li, You-Qun Chu, Chun-An Ma Apr 2013

A Comparative Study Of Ce3+/Ce4+ Redox Couple On Pt Electrode In Sulfuric Acid And Methanesulfonic Acid, Zhao-Hua Li, You-Qun Chu, Chun-An Ma

Journal of Electrochemistry

The electrochemical oxidations of Ce3+ to Ce4+ on Pt rotating disk electrode (RDE) in both sulfuric acid and methanesulfonic acid (MSA) solutions were studied by using cyclic voltammetry and linear sweep voltammetry. The complexing behaviors of Ce3+/Ce4+ were preliminarily probed and the exchange current density, diffusion coefficient, as well as reaction rate constant were obtained from Butler-Volmer equation. The activation energies of Ce3+ oxidation on Pt electrode in two types of acidic media, obtained from Arrhenius equation, were also compared. The results indicate that Ce3+ can be oxidized to Ce4+ much easier in …


Properties Of Carbon Coated Tin Negative Electrode For Lithium-Ion Battery, Gui-Chang Liu, Xiao-Xiao Shen, Li-Da Wang Apr 2013

Properties Of Carbon Coated Tin Negative Electrode For Lithium-Ion Battery, Gui-Chang Liu, Xiao-Xiao Shen, Li-Da Wang

Journal of Electrochemistry

Carbon coated tin power was prepared by decomposing glucose applying a hydrothermal method, and was further used as the active material for negative electrode of lithium secondary battery. Charge-discharge tests show that the carbon coated tin electrode with the addition of 5 wt.% acetylene black as a conductive agent could obtain an initial discharge capacity of 967 mAh.g-1 and a discharge capacity of 362 mAh.g-1 after 50 cycles, which is much higher than that of tin electrode (166 mAh.g-1 after 50 cycles). The coated carbon hinders the agglomeration of tin powder, reduces the irreversible capacity loss of …


Preparation And Methanol Electrooxidation Of Pt/Pmo12/Pedot/Gc Electrodes, Jing-Hua Ma, Rui-Xiang Wang, Yi-Liang Tan, Shan-Shan Wang, Yan-Qin Zhang, You-Jun Fan Apr 2013

Preparation And Methanol Electrooxidation Of Pt/Pmo12/Pedot/Gc Electrodes, Jing-Hua Ma, Rui-Xiang Wang, Yi-Liang Tan, Shan-Shan Wang, Yan-Qin Zhang, You-Jun Fan

Journal of Electrochemistry

Modification of phosphomolybdic acid (PMo12) on poly(3,4-ethylenedioxythiophene) (PEDOT) film (PEDOT/GC) obtained through the electrochemical polymerization was performed using adsorption method (PMo12/PEDOT/GC), followed by electrodepositing Pt on PMo12/PEDOT/GC to prepare Pt/PMo12/PEDOT/GC electrode. Effects of PMo12 and PEDOT on the methanol oxidation performance of electrode were investigated. Results showed that PMo12 obviously changed the morphology and structure of Pt loaded on the electrode, leading to the formation of sharp thorns at the edge of Pt nanostructures. Cyclic voltammetry and chronoamperometry data demonstrated that the catalytic activities of methanol electrooxidation on the Pt/PMo …


Electrochemical Activities Of Oxygen-Doped Carbon Surface For V(Iv)/V(V) Redox Couple, Huan Zhang, Lin-Lin Qin, Yi-Ning Shi, Ming-Sen Zheng, Quan-Feng Dong, Zhao-Wu Tian Apr 2013

Electrochemical Activities Of Oxygen-Doped Carbon Surface For V(Iv)/V(V) Redox Couple, Huan Zhang, Lin-Lin Qin, Yi-Ning Shi, Ming-Sen Zheng, Quan-Feng Dong, Zhao-Wu Tian

Journal of Electrochemistry

Graphite plate electrodes were treated with oxygen plasma and doped with oxygen as well as oxygen functional groups. With the treatment, the activities of graphite plate electrodes toward VO2+/VO2+ redox reactions were improved. FT-IR and EDS analysis results indicated that oxygen functional groups were introduced to the surface of graphite plates after oxygen plasma treatment. In this paper, the graphite plate treated for 20 min showed the highest activity. The average charge efficiency reached 91%, suggesting an increase of 19%, compared with that of the untreated graphite plate under a current density of 8 mA·cm-2 …


Synthesis And Electrocatalysis Of Pdcu Alloy Nanocrystals, Hai-Bin Wu, Rui-Zhong Zhang, Wei Chen Apr 2013

Synthesis And Electrocatalysis Of Pdcu Alloy Nanocrystals, Hai-Bin Wu, Rui-Zhong Zhang, Wei Chen

Journal of Electrochemistry

Monodispersed PdCu alloy nanoparticles were synthesized by co-reduction of Cu(acac)2 and Pd(acac)2 with 1, 2-hexadecanediol. The spherical and popcorn-like shapes of PdCu alloy nanoparticles were obtained by changing the ratios of mixed surface protecting ligands of 1-octadecene, and oleylamine or oleic acid. TEM and XRD measurements showed that both PdCu nanoparticles are alloy nanocrystals dominated with (111) planes and the average sizes are 12.7 ± 0.18 and 20.4 ± 0.31 nm for he spherical and popcorn-like PdCu nanoparticles, respectively. The electrocatalytic activities of the PdCu nanocrystals for formic acid oxidation were evaluated by electrochemical cyclic voltammetry (CV). The result showed …


Hydrothermal Synthesis Of Pure Li4Ti5O12 And Its Electrochemical Performance, Wen-Jun Xie, Yu-Shi He, Hong Wang, Xiao-Zhen Liao, Zi-Feng Ma Apr 2013

Hydrothermal Synthesis Of Pure Li4Ti5O12 And Its Electrochemical Performance, Wen-Jun Xie, Yu-Shi He, Hong Wang, Xiao-Zhen Liao, Zi-Feng Ma

Journal of Electrochemistry

Spinel Li4Ti5O12 was prepared by hydrothermal method using commercial anatase (TiO2) and lithium hydroxide (LiOH) as raw materials. The effects of the LiOH concentration of lithium hydroxide, hydrothermal reaction time and calcination temperature on the structure and electrochemical performance of Li4Ti5O12 were investigated. The formation process of Li4Ti5O12 was also proposed. The micro-structure and morphology wereas characterized by XRD, SEM, TEM techniques, and the electrochemical performance was analyzed by galvanostatic charge-discharge test. The results show that the pure phase spinel Li4Ti5O12 can be …


Electrochemical Performance Of Lifepo4/C Synthesized Via Aqueous Solution-Evaporation Route, Ning-Yu Gu, Xing-Hua He, Yang Li Apr 2013

Electrochemical Performance Of Lifepo4/C Synthesized Via Aqueous Solution-Evaporation Route, Ning-Yu Gu, Xing-Hua He, Yang Li

Journal of Electrochemistry

The LiFePO4/C samples have been synthesized via an aqueous solution-evaporation route with LiH2PO4, FeC2O4.2H2O as raw materials and citric acid as a carbon source. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to analyze structure and morphology of the samples. The electrochemical performances of the LiFePO4/C cathodes were characterized by charge/discharge cures and electrochemical impedance spectroscopy (EIS). The results show that the LiFePO4/C sample, calcined at 700 °C and contained 3.03% (by mass) carbon, exhibited a highly pure …


Synthesis And Electrochemical Performance Of Si/C Composite Modified By Pani, Guang-Hui Zhang, Pei-Kang Shen, Ge Sang, Ren-Jin Xiong Apr 2013

Synthesis And Electrochemical Performance Of Si/C Composite Modified By Pani, Guang-Hui Zhang, Pei-Kang Shen, Ge Sang, Ren-Jin Xiong

Journal of Electrochemistry

Silicon/carbon (Si/C) composite materials were prepared through high-energy ball milling and high-temperature solid-phase method, and then coated with thin polyaniline (PAni) film by oxidation. The microstructure and component of the composites were characterized by SEM, XRD, IR, TG, and the electrochemical performance was investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge tests. The results showed that the surface of PAni/Si/G/C composite was coating with complete lamellar structure of PAni film. Its reversible capacity was 784 mAh.g-1and 690 mAh.g-1 could be maintained after 50th charge-discharge cycles.


Synthesis Of Lifepo4/C Cathode By Sol-Gel And Calcining Method With Chitosan Monomer, Jia Xu, Yan-Yan Wang, Rui Wang, Bo Wang, Yue Pan, Dian-Xue Cao, Gui-Ling Wang Apr 2013

Synthesis Of Lifepo4/C Cathode By Sol-Gel And Calcining Method With Chitosan Monomer, Jia Xu, Yan-Yan Wang, Rui Wang, Bo Wang, Yue Pan, Dian-Xue Cao, Gui-Ling Wang

Journal of Electrochemistry

The LiFePO4/C cathode materials for Li-ion battery were synthesized by sol-gel and calcining method using chitosan monomer as a carbon source and a gelating agent. The structures and morphologies were characterized by X-ray diffraction spectroscopy (XRD) and scanning electron microscopy (SEM). The electrochemical performance was investigated by the galvanostatic charge–discharge test. When the molar ratios between chitosan monomer and LiFePO4 were 1:1.2, the LiFePO4/C cathode calcined at 600 oC showed the best performance. The particle sizes ranged 200 ~ 400 nm. The initial discharge capacity of 155 mAh.g-1 was achieved at room temperature …


Current Development Of Quantum Dots Based Electrochemiluminescence Immunosensors, Ling-Ling Li, Qian Lu, Jun-Jie Zhu Apr 2013

Current Development Of Quantum Dots Based Electrochemiluminescence Immunosensors, Ling-Ling Li, Qian Lu, Jun-Jie Zhu

Journal of Electrochemistry

Electrochemiluminescence exhibits the merits of both luminescence and electrochemistry analysis, and has been extensively employed in biosensors. Quantum dots are considered one of the three main kinds of electrochemiluminescence luminophores due to their unique properties. This paper briefly reviews the classification and signal amplification technology of quantum dots based electrochemiluminescence immunosensors. Future research trends are also suggested.


Electrochemical Synthesis Of Hierarchical Dendritic Polyaniline Nanostructures, Shao-Huang Weng, Jian-Zhang Zhou, Zhong-Hua Lin, Xin-Hua Lin Apr 2013

Electrochemical Synthesis Of Hierarchical Dendritic Polyaniline Nanostructures, Shao-Huang Weng, Jian-Zhang Zhou, Zhong-Hua Lin, Xin-Hua Lin

Journal of Electrochemistry

In this work, the p-TSA doped and hierarchical dendritic nanostructured polyanilines (PANI) have been prepared by potentiostatic electropolymerization without using any templates at room temperature. The mechanism of the polymerization has been discussed according to the electrodeposition curves. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to confirm the formation of uniform hierarchical dendritic structure on PANI. UV-Vis spectroscopy (UV-Vis) and infrared spectroscopy (FTIR) proved that the prepared PANI is in the form of emeraldine salt. The templateless electrodeposition method is simple, easy to operate, can be applied to fabricate other nanostructures of conducting polymers.


Performance Of Vn As Negative Electrode Materials In Electrochemical Capacitors, Zhao-Hui Gao, Hao Zhang, Gao-Ping Cao, Min-Fang Han, Yu-Sheng Yang Apr 2013

Performance Of Vn As Negative Electrode Materials In Electrochemical Capacitors, Zhao-Hui Gao, Hao Zhang, Gao-Ping Cao, Min-Fang Han, Yu-Sheng Yang

Journal of Electrochemistry

Nanocrystalline vanadium nitride (VN) materials were synthesized by high temperature ammonia (NH3) reduction of vanadium oxide (V2O5). The structure and morphology of VN materials were characterized by XRD,SEM and TEM, while the specific surface area, pore size distribution and supercapacitive behavior by N2 absorption, cyclic voltammetry (CV) and constant current charge-discharge measurements in 1 mol?L-1 KOH electrolyte. The results showed that the VN sample belonged to the cubic crystal system (Fm3m [225]),and had homogeneous surface and appeared nearly spherical with uniform size. As the reaction time was extended to 12 h,small particles were interconnected …


Preparation And Catalytic Properties Of Feco Alloy Nanocatalyst, Ming-Xuan Li, Jie-Lian Ou, Sheng-Pei Chen, Peng Wang, Bin-Bin Xu, Shi-Gang Sun Apr 2013

Preparation And Catalytic Properties Of Feco Alloy Nanocatalyst, Ming-Xuan Li, Jie-Lian Ou, Sheng-Pei Chen, Peng Wang, Bin-Bin Xu, Shi-Gang Sun

Journal of Electrochemistry

The FeCo alloy nanoparticles were electrodeposited on glassy carbon electrode by chronoamperometry and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that the shapes of FeCo nanoparticles were cubes with an average size of 65 nm. The atom ratio of Fe and Co is 1:1. As indicated from the pattern of selected area electron diffraction (SAED), the FeCo cubic nanoparticles were single crystal which belonged to body-centered cubic with an interval of 0.201 nm referring to the (110) facets of FeCo alloy. The FeCo cubic nanoparticles exhibited the enhanced electrocatalytic …