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Full-Text Articles in Physical Sciences and Mathematics

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.


Current Statuses And Prospects Of Bioeletrochemical Instruments, Ren Hu, Chun-Hui Piao, Chang-Jian Lin, Dong-Ping Zhan, Bin Ren, Amatore Christian, Zhong-Qun Tian Apr 2013

Current Statuses And Prospects Of Bioeletrochemical Instruments, Ren Hu, Chun-Hui Piao, Chang-Jian Lin, Dong-Ping Zhan, Bin Ren, Amatore Christian, Zhong-Qun Tian

Journal of Electrochemistry

Charge transfer is one of the essential life processes. In the past decades, the electrochemical methods have been developed to study life science in a unique physicochemical view and have exhibited abundant and precious information beyond conventional biological techniques. As bioelectrochemical research areas evolved from the fundamental studies of biomolecules’ electrochemical behaviours in non-living conditions to the living cells in intro and in vivo, and further to the single molecule in living systems, the role of instruments becomes more and more crucial. The performances of instruments such as sensitivity, resolution (time, spatial and eneygy resolutions) and controllability are more demanding …


Fabrication And Localized Surface Plasmon Resonance Of Ultrathin Nanoporous Gold Films, Feng Shi, Chen Shu, Yang Qing, Xiang Juan Apr 2013

Fabrication And Localized Surface Plasmon Resonance Of Ultrathin Nanoporous Gold Films, Feng Shi, Chen Shu, Yang Qing, Xiang Juan

Journal of Electrochemistry

Ultrathin nanoporous gold films (NPGF) with a thickness of approximately 50 nm were fabricated via electrochemical dealloy method. The morphology of NPGF was evaluated with a parameter of surface roughness. SEM results demonstrate that the fabrication of NPGF with different roughness factors can be achieved by controlling the circles of cyclic voltammetry. UV-Vis spectra indicate that the localized surface plasmon resonance (LSPR) of NPGF is affected by the roughness of NPGF. With the optimal roughness factor, NPGF displays a linear relationship between the ethanediol concentration and the absorbance intensity at λ = 450 nm. The LSPR effect of NPGF presents …


The Electrochemical Capacitance Performance Of La1-XSrXCoo3 Perovskites, Yang Xu, Yan-Yan Bao, Long-Fei Du, Dian-Xue Cao, Gui-Ling Wang Apr 2013

The Electrochemical Capacitance Performance Of La1-XSrXCoo3 Perovskites, Yang Xu, Yan-Yan Bao, Long-Fei Du, Dian-Xue Cao, Gui-Ling Wang

Journal of Electrochemistry

In this paper, the La1-xSrxCoO3 (x = 0.2, 0.4, 0.6, 0.8) perovskites powders were synthesized by a sol-gel method. The perovskite phases were characterized by X-ray diffraction (XRD), while the electrochemical capacitance performance of La1-xSrxCoO3 electrodes in alkaline electrolyte was studied by cyclic voltammetry and galvanostatic charge/discharge test. It was found that the La0.6Sr0.4CoO3 electrode exhibited a specific capacitance of 325 F.g-1 in 6.0 mol.L-1 KOH electrolyte at a current density of 10 mA.cm-2, and the specific capacitance of 315 F.g …


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 …


An Electrochemical Impedance Spectroscopic Study Of Cuf2/Moo3/C Cathode Composites, Yue-Li Shi, Nan Wu, Ming-Fang Shen, Jia-Qun Dong, Quang-Chao Zhuang, Li Jiang Apr 2013

An Electrochemical Impedance Spectroscopic Study Of Cuf2/Moo3/C Cathode Composites, Yue-Li Shi, Nan Wu, Ming-Fang Shen, Jia-Qun Dong, Quang-Chao Zhuang, Li Jiang

Journal of Electrochemistry

Composite electrode of CuF2/MoO3/C was fabricated through high energy mechanical milling. The properties of CuF2/MoO3/C were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (TEM), galvanostatic charge-discharge measurements, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results showed that the grain sizes of CuF2 and MoO3 after milling were 200 ~ 300 nm, and the initial discharge capacity of CuF2/MoO3/C was 647 mAh?g-1 at room temperature and at a current density of 10 mA.g-1. However, the capacity …


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 …


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 …


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 …


Analysis Of The Material Factors In The Degradation Of Sofc Performance, Ke-Qing Gao, Xiao-Tian Liu, Qing Zhao, Li-Quan Fan, Yue-Ping Xiong Apr 2013

Analysis Of The Material Factors In The Degradation Of Sofc Performance, Ke-Qing Gao, Xiao-Tian Liu, Qing Zhao, Li-Quan Fan, Yue-Ping Xiong

Journal of Electrochemistry

Based on the cell operating conditions, the material factors which influence the cell performance of SOFC including the chemical stability of materials at solid-gas interface in redox atmosphere, the diffusion and reaction between the interface of solid-solid materials, and degradation caused by the external chemical substances brought into the cells at triple phase boundary are mainly analyzed. Given that under the current state of the research it is urgent to explore the material factors on degradation of cell performance to meet demands in SOFC applications.


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 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 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 …


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 …


Physical Essentials Of Rotating Complex Impedance Diagram In Some Electrochemical Systems, Bing-Liang Wu Feb 2013

Physical Essentials Of Rotating Complex Impedance Diagram In Some Electrochemical Systems, Bing-Liang Wu

Journal of Electrochemistry

The essential of the rotation of complex impedance diagram in some electrochemical systems is discussed. It is attributing to that the electrochemical capacitance usual is not simple real capacitor but must be complex number capacitance. As the examples: 1, the metal/support electrolyte electrode in the ideal polarization condition, the capacitance must be that of the electrochemical double layer and represents complex number properties. Its complex impedance diagram was not a line parallel to imaginary axis but rotated clockwise α=arctgC"/C'. 2, In the case of insertion/desertion electrodes, the capacitance must be that of the solid electrolyte interphase (SEI). The rotation of …


High Performance Membrane Electrode Assembly With Low Platinum Loadings Prepared By Atomic Layer Deposition For Pemfc Application, Ting Shu, Shi-Jun Liao, Chien-Te Hsieh, Ay Su Feb 2013

High Performance Membrane Electrode Assembly With Low Platinum Loadings Prepared By Atomic Layer Deposition For Pemfc Application, Ting Shu, Shi-Jun Liao, Chien-Te Hsieh, Ay Su

Journal of Electrochemistry

A high performance membrane electrode assembly (MEA) with low platinum loadings was successfully prepared with atomic layer deposition (ALD) technique. The anode of the MEA was prepared by depositing platinum on the carbon paper substrate, which was prepared by coating the slurry of carbon black (XC-72R) and Teflon, followed by drying and calcining at 350 °C. The MEAs consisted of the ALD anode or commercial catalyst anode, pretreated Nafion membrane (Nafion-117) and commercial cathode. Performances of MEAs were measured by single cell testing, and the anodes and MEAs were characterized by CV, SEM, TEM and XRD. The results revealed that …


Sodium Carbonate Catalyzed Photoelectrochemical Water Splitting Over Tio2 Nanotubes Photoanode, De-Sheng Kong, Jing Wang, Xue-Di Zhang, Xi Zhao, Chao Wang, Yuan-Yuan Feng, Wen-Juan Li Feb 2013

Sodium Carbonate Catalyzed Photoelectrochemical Water Splitting Over Tio2 Nanotubes Photoanode, De-Sheng Kong, Jing Wang, Xue-Di Zhang, Xi Zhao, Chao Wang, Yuan-Yuan Feng, Wen-Juan Li

Journal of Electrochemistry

Surface recombination of the photogenerated electron-hole pairs at semiconductor/electrolyte interface is one of the most essential reasons responsible for lowering photoconversion efficiency (Φ) of light to chemical energy for photoelectrochemical (PEC) water splitting reaction. In this paper,the catalytic effect of sodium carbonate on the oxygen evolution reaction (OER) over TiO2 nanotubes photoanode during PEC water splitting was investigated by performing photocurrent and ac impedance measurements. It was demonstrated that the addiction of 1 mmol•L-1 Na2CO3 in 0.5 mol•L-1 NaClO4 electrolyte can effectively improve the charge transfer properties for the photogenerated holes …


Effect Of Ti/Pbo2 Electrodes Doped With Different Elements On Electrocatalytic Oxidation Characteristics Of Phenol, Xiao-Lei Liu, Yuan-Yuan Dan, Hai-Yan Lu, Hai-Bo Lin, Ming-Li Ouyang, Chuan-Jun Yun Feb 2013

Effect Of Ti/Pbo2 Electrodes Doped With Different Elements On Electrocatalytic Oxidation Characteristics Of Phenol, Xiao-Lei Liu, Yuan-Yuan Dan, Hai-Yan Lu, Hai-Bo Lin, Ming-Li Ouyang, Chuan-Jun Yun

Journal of Electrochemistry

Three types of electrodes, namely, Ti/PbO2, F-doped PbO2 (Ti/PbO2-F) and nano-Co3O4-doped PbO2 (Ti/PbO2+Nano-Co3O4) electrodes, were prepared by electro-deposition method on the Ti substrate with the interlayer of SnO2-Sb2O5. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to study the compositions, structures and film morphologies of the electrodes. Electrocatalytic oxidation characteristics to phenol on the prepared electrodes were investigated by electrochemical method. The experimental results showed that compared with the Ti/PbO2 electrode, the potentials of oxygen …


A Dft Calculation Screening Of Pt-Based Bimetallic Catalysts For Oxygen Reduction, Li-Hui Ou, Sheng-Li Chen Feb 2013

A Dft Calculation Screening Of Pt-Based Bimetallic Catalysts For Oxygen Reduction, Li-Hui Ou, Sheng-Li Chen

Journal of Electrochemistry

Developing Pt-lean catalysts for oxygen reduction reaction (ORR) is the key for large-scale application of proton exchange membrane fuel cell (PEMFC). In this paper, we have proposed a multiple-descriptor strategy for screening efficient and durable ORR alloy catalysts of low Pt content. We argue that an ideal Pt-based bimetallic alloy catalyst for ORR should possess simultaneously negative alloy formation energy, negative surface segregation energy of Pt and a lower oxygen binding ability than pure Pt. By performing detailed DFT calculations on the thermodynamics, surface chemistry and electronic properties of various Pt-M alloys (M refers to non-precious transition metals in the …


An In Situ Ftir Spectroelectrochemical Study On Methanol Oxidation At Pt-Mo2c/Gc Catalyst, Hai-Ping Huang, Xi-Yu Yao, Pei-Kang Shen Feb 2013

An In Situ Ftir Spectroelectrochemical Study On Methanol Oxidation At Pt-Mo2c/Gc Catalyst, Hai-Ping Huang, Xi-Yu Yao, Pei-Kang Shen

Journal of Electrochemistry

A 40% Pt on Mo2C/GC catalyst has been prepared by ion exchange method. The mechanism of methanol electrooxidation on Pt-Mo2C/GC and commercial Pt/C catalysts in acidic media was studied by cyclic voltammetry, XRD measurements and in-situ Fourier transform infrared spectroelectrochemistry. The results revealed that the Pt nanoparticles were uniformly dispersed on Mo2C/GC with an average particle size of 3 nm. The cyclic voltammetric and chronopotentiometric experiments indicated that Pt-Mo2C/GC catalyst exhibited a better performance for methanol oxidation than that of Pt/C in acid solution. A negative shift over 90 mV of the onset potential for methanol oxidation was found on …


Electrochemical Performance Of Fe3o4/C Composites As Negative Material For Lithium-Ion Batteries, Jun-Jie Cai, Shu Yao, Ze-Sheng Li, Hui Meng, Pei-Kang Shen Feb 2013

Electrochemical Performance Of Fe3o4/C Composites As Negative Material For Lithium-Ion Batteries, Jun-Jie Cai, Shu Yao, Ze-Sheng Li, Hui Meng, Pei-Kang Shen

Journal of Electrochemistry

The Fe3O4/Carbon composites have been synthesized through coprecipitation pathway and by insitu aniline polymerization as a carbon source. Structural characterization and morphological study of the composites were investigated by using XRD, SEM and TEM techniques. The results showed that the nanosized Fe3O4 particles (40 ~ 80 nm) were encapsulated in the amorphous carbon. During the electrochemical tests, the Fe3O4/C composites exhibited high capaticity and excellent cycle ability, the retention of capaticity was about 1000 mAh?g-1 after 30 cycles of charge/discharge tests at 50 mA?g-1.


Oxygen Reduction Reaction On Glycin Modified Pt(111) Electrode, Ming-Fang Li, Jing Kang, Ling-Wen Liao, Yan-Xia Chen, Shen Ye Feb 2013

Oxygen Reduction Reaction On Glycin Modified Pt(111) Electrode, Ming-Fang Li, Jing Kang, Ling-Wen Liao, Yan-Xia Chen, Shen Ye

Journal of Electrochemistry

Oxygen reduction reaction (ORR) on glycin (NH2CH2COOH) modified Pt(111) electrode has been investigated using hanging meniscus rotating disk electrode system (HMRD) in 0.05 mol•L-1 H2SO4 and 0.1 mol•L-1 HClO4 solutions, respectively. Cyclic voltammograms of the glycin modified Pt (111) electrode measured in 0.05 mol•L-1 H2SO4 solution similar to that of CN- modified Pt(111) electrodes, demonstrating that sulfate adsorption is strongly inhibited at the glycin modified Pt(111). From the polarization curve of ORR recorded in 0.05 mol•L-1 H2SO4 solution, it is found that the ORR activity …


A Comparative Study Of Charge-Discharge Behaviors Of Α-Pbo2 And Β-Pbo2 Cathodes, Cong-Ying Cui, Xue-Mei Ma, De-Long Kong, Hou-Yi Ma Feb 2013

A Comparative Study Of Charge-Discharge Behaviors Of Α-Pbo2 And Β-Pbo2 Cathodes, Cong-Ying Cui, Xue-Mei Ma, De-Long Kong, Hou-Yi Ma

Journal of Electrochemistry

The α-PbO2 and β-PbO2 powders were prepared using simple chemical synthetic methods, and their crystalline structures and surface morphologies were characterized with X-ray powder diffraction spectroscopy and scanning electron microscopy. Using the as-synthesized α-PbO2 and β-PbO2 powders as positive active materials, the electrochemical performance of the two PbO2 materials was investigated by means of cyclic voltammetry, galvanostatic charge-discharge tests, and electrochemical impedance spectroscopy. The results indicate that the discharge capacity of α-PbO2 electrode is larger than that of β-PbO2; moreover, the composite electrodes made by α-PbO2 and β-PbO2 mixtures with different proportions are favorable for enhancing the charge-discharge cycle performance …


Porous Electrodes With High Pt Utilization Obtained By Ion-Exchange/Electrodeposition, Si-Guo Chen, Wei Ding, Xue-Qiang Qi, Li Li, Zi-Hua Deng, Zi-Dong Wei Feb 2013

Porous Electrodes With High Pt Utilization Obtained By Ion-Exchange/Electrodeposition, Si-Guo Chen, Wei Ding, Xue-Qiang Qi, Li Li, Zi-Hua Deng, Zi-Dong Wei

Journal of Electrochemistry

We report a novel method based on ion-exchange/electrodeposition (IEE) for constructing high Pt utilization porous electrodes. The electrode prepared using IEE was assessed by linear sweep voltammetry (LSV), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and single cell test. The preliminary results show that the undesired ion-exchange between Pt anion and surface functional group in carbon black can be eliminated through the electrode preparation process, and every Pt particle prepared by IEE is expected to be deposited on the three-phase reaction zone and thus can be fully utilized in fuel cell reactions. The Pt particle size, shape and distribution …


Combination And Applications Of Time-Resolved Surface Plasmon Resonance Spectroscopy And Electrochemical Methods, Yu Bao, Yan Mao, Wei Wang, Zheng-Gang Li, Li Niu Feb 2013

Combination And Applications Of Time-Resolved Surface Plasmon Resonance Spectroscopy And Electrochemical Methods, Yu Bao, Yan Mao, Wei Wang, Zheng-Gang Li, Li Niu

Journal of Electrochemistry

Electrochemical-surface plasmon resonance (EC-SPR) technique, developed in recent years, is a new technology which combines time-resolved surface plasmon resonance spectroscopy and electrochemical methods. Surface plasmon resonance (SPR) is a physical phenomenon generated by optical coupling using a metallic thin film and is very sensitive to optical analysis. The principles of SPR and EC-SPR are briefly introduced and the applications of the combination of SPR spectroscopy with electrochemical techniques are reviewed in this paper. This new technology has been widely used in such research areas as reaction dynamics, biochemical sensors, electrode/electrolyte interfaces, kinetic parameters and bimolecular interactions.


Recent Experimental Progresses On Electrochemical Atr-Seiras, Yao-Yue Yang, Han-Xuan Zhang, Wen-Bin Cai Feb 2013

Recent Experimental Progresses On Electrochemical Atr-Seiras, Yao-Yue Yang, Han-Xuan Zhang, Wen-Bin Cai

Journal of Electrochemistry

Technical aspects on developing electrochemical ATR surface-enhanced infrared absorption spectroscopy are briefly accounted mainly based on our recent investigations, including wet-fabrication of metallic film electrodes on Si prism, design and construction of a wide-frequency combination optical window and a spectroelectrochemical cell switchable for external and internal reflection modes.


Applications Of Ellipsometry In The Investigations Of Electrode-Solution Interface, Jing-Lei Lei, Liang-Liu Wu, Ling-Jie Li, Sheng-Mao Wu, Sheng-Tao Zhang Feb 2013

Applications Of Ellipsometry In The Investigations Of Electrode-Solution Interface, Jing-Lei Lei, Liang-Liu Wu, Ling-Jie Li, Sheng-Mao Wu, Sheng-Tao Zhang

Journal of Electrochemistry

Ellipsometry is an optical technique with high-sensitivity to quantitatively obtain surface/interface properties such as thickness andrefractive index by analyzing the changes in polarized light reflected from the surface/interface. Its noncontacting and nondestructivenature makes it possible to acquire thein situreal-time information of the change at the surface/interface. Therefore, ellipsometry has been used widely in the electrochemical investigations. In this paper, based on the brief introduction of the measurementprinciple of ellipsometry, the current progress and the future trends of ellipsometry in electrochemistry arediscussed. The applications of ellipsometry in the fields of conversion and storage of electrochemical energy, electrochemistry ofmaterials science,electroanalysisand bioelectrochemistry are …


Adsorption And Electrooxidation Of Carbon Monoxide On Platinum Surfaces Modified With Sulfur, A. Mattox Mathew, W. Henney Matthew, Johnson Adam, Zou Shouzhong Dec 2012

Adsorption And Electrooxidation Of Carbon Monoxide On Platinum Surfaces Modified With Sulfur, A. Mattox Mathew, W. Henney Matthew, Johnson Adam, Zou Shouzhong

Journal of Electrochemistry

Adsorbed sulfur is commonly considered as a reaction poison. However, small amounts of sulfur on platinum significantly increase the surface reactivity toward carbon monoxide (CO) electrooxidation. For the solution CO oxidation, the onset potential was shifted up to over 300 mV negative to that on S-free surface, and the extent of the negative potential shift increases with the sulfur coverage (Xs) up to about 0.6. The enhanced CO oxidation also depends on the solution pH. For the adsorbed CO, at low sulfur coverages (Xs < 0.3), the oxidation peak potential is about 40 mV negative to that of the corresponding clean Pt. However, at higher coverages, the peak potential is about 30 mV more positive. Surface-enhanced Raman spectra show that the adsorption of sulfur significantly redshifts the Pt-CO stretching frequency. These observations are explained by the weakening of the Pt-CO bond and the hindrance of CO diffusion by Sads.


Electrocatalytic Activity Of Palladium Nanocatalysts Supported On Carbon Nanoparticles In Formic Acid Oxidation, Jie Huang, Zhiyou Zhou, Yang Song, Xiongwu Kang, Ke Liu, Wancheng Zhou, Shaowei Chen Dec 2012

Electrocatalytic Activity Of Palladium Nanocatalysts Supported On Carbon Nanoparticles In Formic Acid Oxidation, Jie Huang, Zhiyou Zhou, Yang Song, Xiongwu Kang, Ke Liu, Wancheng Zhou, Shaowei Chen

Journal of Electrochemistry

Palladium nanostructures were deposited onto carbon nanoparticle surface by a chemical reduction method. Transmission electron microscopic studies showed that whereas the resulting metal-carbon (Pd-CNP) nanocomposites exhibited a diameter of 20 to 30 nm, the metal components actually showed a cauliflower-like surface morphology that consisted of numerous smaller Pd nanoparticles (3 to 8 nm). Electrochemical studies showed that the effective surface area of the Pd-CNP nanoparticles was about 40% less than that of Pd black, possibly because the Pd nanoparticles were coated with a layer of carbon nanoparticles; yet, the Pd-CNP nanocomposites exhibited marked enhancement of the electrocatalytic activity in formic …