Power and Energy Commons^™

The Optimal Sulfonation Conditions Of Self-Doped Polyaniline Obtained By Using Experimental Strategies, Wen-Yar Li, Chi-Chang Hu

Journal of Electrochemistry

The optimal sulfonation condition of self-doped sulfonated polyaniline(prepared from leucoemeraldinebase;denoted as LEB-SPANI) with a high electronic conductivity was obtained by experimental strategies,includingthe fractional factorial design(FFD) and central composite design(CCD).From the FFD experiment,the self-doped LEB-SPANI prepared at a lowtemperature(4oC),a short reaction time(1 h),and a small volume of fumingsulfuric acid(10 mL) showed a better conductivity(ca.127 mS/cm).In the CCD study coupled with a confirmationtest,the highest conductivity(ca.141 mS/cm) of the LEB-SPANI film was obtained under a sulfonation temperatureof 4oC,a sulfonation time of75 minutes,and a volume of8 mLof30% fuming sulfuric acid.The textural cha-racter-istics of self-doped LEB-SPANI were characterized by Fourier transform infrared(FTIR) spectroscopy,four-pointprobe method,and X-ray …

Silicides And Composites Materials As Anodes For Lithium Ion Batteries, Jun-Mei Yan

Journal of Electrochemistry

The anode materials of Mg_(2)Si and MnSi were synthesized by mechanically activated annealing(MAA) techniques in this work and the in electrochemical performances were also studied.A series of composite materials of Mg_(2)Si and CNTs or CMS were prepared by ball-milling method respectively.The reversible capacities of the composites were higher than that of the pure Mg_(2)Si and pure carbon materials.The cyclic performances have been improved greatly by ball-milling of the Mg_(2)Si and carbon materials.Results show that ball-milling method is one kind of method to make alloy materials into practical use.

A Continuous Operation For Electroreduction Of Oxalic Acid To Glyoxylic Acid, Xiao-Hui Hu, Xiang-Fei Yan, Yu-Zhong Su, Jun Li

Journal of Electrochemistry

A simulative-continuous-operation approach was proposed to study the continuous operation for electroreduction of oxalic acid to gloxylic acid using a packed bed reactor and a parallel reactor with cooled cathode in order to solve the low productivity problem in current state by using traditional reactor.The effects of the concentration of oxalic acid and temperature on this process were also studied.Results showed that,after 30min of the reaction(residence time),the mass fraction of the produced glyoxylic acid in the catholic solution could reach 3.76% and 3.66% with respect to a saturated oxalic acid method and a step-temperature decreasing method.From this study,we conclude that …

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

Journal of Electrochemistry

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

The Electrocatalystic Investigation Of 3,4-Dihydroxybenzoic Acid On The Modified Multiply Wall Carbon Nanotubes, Ming-Qi Li

Journal of Electrochemistry

The electrochemical behavior of 3,4-Dihydroxybenzoic acid(DHBA)on modified multiply wall carbon nanotubes electrode was investigated by cyclic voltammetry(CV) and square wave voltammetry(SWV).Results show that in 0.1 mol/L HCl solutions the modified carbon nanotube electrode has an obvious electrocatalytic effect on the oxidation and deoxidization of DHBA.The oxidation current of DHBA is linear to it's concentration in the range of 4.0×10~(-6)～1.0×10~(-4) mol/L and 2.0×10~(-4)～8.0×10~(-4)1mol/L with correlation coefficient of 0.9995 and 0.9992.The detection limit is 1.0 ×10~(-6)mol/ L.

Solid Oxide Fuel Cells-Materials And Prospects, Molenda Janina, Marzec Jacek

Journal of Electrochemistry

The paper summarizes and discusses the basic properties of solid oxide fuel cell(SOFC) components(electrode materials and electrolyte) from the point of view of their essential functional parameters suck as chemicalstability,transport,catalytic and thermomechanical properties under operational conditions in a SOFC.An interrela-tion between the defect structure of these materials related to oxygen nonstoichiometry and their electronic propertiesand catalytic activity was shown.Single-chamber fuel cell concept was also presented.

A Study Of Overcharge Characteristic Of Lithium-Ion Cells, Jing Pang, Shi-Gang Lu, Sha Liu

Journal of Electrochemistry

The overcharge characteristics and effect factors of lithium-ion cells containing LiMn_(2)O_(4)cathodes were studied in detail.Overcharge testing of Lithium-ion cells with a systematic variation in the cell balance demonstrated that the overcharge characteristics of Lithium-ion cells was affected by the amount of cathode in the cells,which is independent of the amount of anode material.The rate of charge was found to be an important parameter,as electrolyte complete decomposition at low charge rates caused the end of overcharge testing,while high charge rates accelerated the rate of heat generation in the cells and the cell temperature increased as a result of insufficient heat dissipation.The …

The Deactivation Mechanism Of Metal Oxide Anodes Under Alternative Current Electrolysis Condition, Jun-Tao Wang

Journal of Electrochemistry

The metal oxide anodes coated on titanium used in seawater electrolysis were prepared by thermal decomposition.Their morphologies、compositions and phase structures were determined by scanning electron microscope(SEM)、energy dispersive X-ray detector(EDX) and X-ray diffraction(XRD).The electrochemical properties of the anodes were characterized by accelerated life test,cyclic voltammetry and electrochemical impedance spectroscopy.SEM、EDX and XRD showed that solid solution structures of(Ru,Ir,Ti)O_(2)and(Ir,Ti)O_(2) were formed after pyrolysis,the solid solution structures and active components were disappeared after the deactivation of the anodes.Electrochemical results indicated that the active area decreased and the coating resistance increased,which are resulted by active component falling off from the anode surfaces.Hence,the deactivation of the …

The Research Of Nano-Sized Nio Anode Materials For Lithium Ion Batteries, Jun-Mei Yan, Jing Zhang, Yong Yang

Journal of Electrochemistry

The nano-sized NiO materials were synthesized by solid phase method and sol-gel method. The synthesis conditions were optimized by DSC and TG techniques. The sol-gel method was optimized by changing the solvent and regulating the solution's pH for preparing NiO material. The structure and morphology of the materials were also characterized by means of XRD and TEM techniques, and the electrochemical performances of the materials were studied by the galvanostatically charge and discharge experiments.

Adsorption Of Polyaspartic Acid From Sulphur Acid Solution On Carbon Steel And Its Corrosion Inhibition, Rong-Jing Cui, Ning Gu, Chun-Mei Li

Journal of Electrochemistry

The role of Polyaspartic acid in the corrosion inhibition of 45~(#) carbon steel in sulphuric acid solution has been investigated by polarization curve andelectrochemical impedance spectroscopy (EIS). The influences of the concentration and the temperature of PASP on the corrosion inhibition efficiency were determined. The results indicated that the PASP as the corrosion inhibitor mainly inhibitated the anode; within the experiment temperature, the inhibitor efficiency decreased with the raising of the temperature and PASP had a good inhibiting performance at 10℃, the corrosion inhibition efficiency of PASP for carbon steel increased with the increase of the concentration of PASP when …

Electrocatalytic Oxidation And Degration Of Active Red X-3b By Nanotubes Catalytic Electrodes, Yi Wen, Jian-Hui Fang

Journal of Electrochemistry

The catalytic splitting decomposition of carbon nanotubes isprocessed by dispersing with dilute nitric acid and thermal oxidation. Then well-proportionedphenolic resin is mixed in the carbon nanotubes. Then, the carbon nanotubesare made into electrodes by hot-press molding after the process of milling with high speed. The surface of the carbon nanotubes electrodes is analyzed by SEM. Active red X-3B simulated waster water is disposed by carbon nanotubes catalyticelectrode (anode) and stainless steel(cathode). The influencing factors of degradation by current density, concentrationof electrolyte, systemtemperature and pH are investigated. The experimental results indicated that acidiccondition is propitious tothe degradationreaction of organicdyestuff and wastewater …

Nafion Emulsion Method For Fuel Cell Membrane-Electrode-Assembly Preparation, Chao-Yang Xia, Lin Zhuang

Journal of Electrochemistry

A Nafion emulsion method for fuel cell membrane-electrode-assembly (MEA) preparation was reported for the first time in this paper. 5 %(by mass) Nafion alcohol solution and non-polar solvent (e.g., cyclohexane) were ultrasonicallymixed to produce Nafion emulsion. The catalyst ink prepared using the thus-obtained Nafion emulsion can be directly cast onto Nafion membrane to make MEA. This method is simple in operation, and effectively preventsthe Nafion membrane swelling, hence is suitable for large-scale application. The MEA thus-prepared showed comparable catalyst efficiencywith respect to the popular transfer-method, and the preliminary performance in room-temperature H_(2)/O_(2 )fuel cell test was satisfying.

Effect Of Sintering Temperatures On Synthesis Of Mgco_(0.4)Mn_(1.6)O_(4 ) Positive Materials In Magnesium Ion Battery, Xiu-Ling Gao, Li-Fang Jiao, Hua-Tang Yuan

Journal of Electrochemistry

The cathode material MgCo_(0.4)Mn_(1.6)O_(4 ) for magnesium ion battery was synthesized by sol-gel method. The TG-DTA and XRD analyses showed that the prepared samples has simple spinel structure. Effect of annealing temperature on electrochemical properties was researched.The result shows that the sample sintered at 700℃ has the best electrochemical properties.

Research Progresses In A Flow Redox Battery, Quan-Feng Dong

Journal of Electrochemistry

As a large scale electrochemical storage device, flow redox battery in which the active materials are flowing electrolytes is different from the common batteries employing solid or gas materials as an electrode. In this paper we introduced flow redox battery in brief, reviewed its development and actual state on (study). The main problem existed in the new device was discussed when viewed with its future developments.

Electrochemical Reduction Characteristics Of Nitrobenzene At The Copper Electrode, Jin-Hong Fan, Wen-Ying Xu, Ting-Yao Gao

Journal of Electrochemistry

The electrochemical reduction characteristics and transition steps of nitrobenzene aqueous solution at the copper electrode, as well as its reduction mechanism were extensively investigatedby using the techniques such as cyclic voltammetry(CV) and linear scan voltammetry(LSV). The results showed that the reduction peaks of nitrobenzene at the copper electrode were located at 0.58 V and 1.32 V or so (vs. SCE), both acidity and alkalinesolutionsfavoredthe reduction of nitrobenzene. The adsorption of compounds followed by the reduction process, which is controlled by the mass transfer step at higher nitrobenzene concentration. In addition, the higher anaerobic degree led to faster reduction rate.

Impact Of Interconnection Photovoltaic/Wind System With Utility On Their Reliability Using A Fuzzy Scheme, Dr. Adel A. Elbaset

Dr. Adel A. Elbaset

Reliability analysis has been considered as an important step in any system design process. a reliable electrical power system means that the system which having sufficient power to feed the load demand during a certain period or in other word, having small Loss of Load Probability (LOLP). LOLP is defined as an expected fraction of load not met by its needed power from electrical power system during its lifetime. Photovoltaic (PV) / Wind Energy System (WES) hybrid electric power system (PV/WES HEPS) differs considerably from the utility grid (UG) in their performance and operating characteristics. With the interconnection of PV/WES …

Study Of Secondary Electron Emission From Niobium At Cryogenic Temperatures, Anoop George

UNLV Theses, Dissertations, Professional Papers, and Capstones

The objective of this project is to study the properties of secondary electron emission from niobium samples, cleaned at the Los Alamos National Laboratory, at cryogenic temperatures to enhance existing multipacting codes with data on the samples. The predominant cause of power loss in radio-frequency superconducting accelerators cavities is multipacting. This project studies the secondary electron distribution from niobium metal due to incident primary electrons. The experiments on the niobium sample are performed in an environment close to that present in a superconducting accelerator cavity.

The experiment is performed in a vacuum chamber capable of achieving ultra high vacuum levels …

A Preliminary Study Of Electrocrystallization Of Bismuth On Glassy Carbon, Min-Li Yang, Zhan-Jun Zhang

Journal of Electrochemistry

The electrocrystallization of bismuth on glassy carbon electrodes (GCEs) from nitrate solutions was studied by cyclic voltammetry and chronoamperometry. Cyclic voltammograms exhibit a crossover between the cathodic and anodic branches, characteristic of the formation of bismuth nuclei on GCEs, and show that the bismuth electrocrystallization on GCEs is a diffusion-controlled reaction. The current transients were analyzed with the Scharifker and the Heerman equations. With the increaseof Bi~(3+)concentration, the non-dimensional plots leaned to the theoretical curve for 3D instantaneous nucleation and growth. The overpotential dependence of nucleation and growth mechanism was also found. With the increase of overpotential, the non-dimensional curve …

The Effect Of Oxidant On Structure And Properties Of Pan/Ptfe Conducting Composite Membrane, Chang-Yuan Tao

Journal of Electrochemistry

The PAn/PTFE conducting composite membrane was prepared by means of in-situ permeating chemical polymerization, with (NH_(4))_(2)S_(2)O_(8) and Na_(3)VO_(4) being used as an oxidant respectively.The polymerization-growth behavior of the aniline by using different oxidant was compared. In addition, the oxidant effect on the structure and properties of conducting composite membrane was discussed. The results of SEM micrographs, pore size distribution and electrochemical methods suggested that using either oxidants could also induce the product with small pore size and dense pore structure. Compared with (NH_(4))_(2)S_(2)O_(8), using Na_(3)VO_(4 ) as an oxidant would induce the polyaniline with denser polymers in the membrane pores, …

Application Of Nickel Foam Electrode For Electroreduction Intermediate Of Purine, Hui-Wen Yang, Xi-En Hu, Xue-Jun Wang

Journal of Electrochemistry

Nickel foam with weight uniformity, good porosity ,pore size and low resistivity as a three-dimensional cathode was used in a filter-press electrochemical reactor. The H_(2)SO_(4) as supporting electrolyte, separator of cation ion exchange membrane, and the lead plate as an anode were used. The cyclic system consisted of electroreduction reactor, pump, store tank and ampere meter. NAU was electroreduced in the cathode chamber of the reactor. Purine intermediate was synthesized with DAU, and the results were compared with those of iron powder reduction process. A peak current in the electroreduction process was detected. The current density of nickel foam increased …

Preparation And Characterization Of Mcm-41/ Pvdf-Hfp Composite Microporous Polymer Electrolytes For Li-Ion Batteries, Zuo-Feng Chen

Journal of Electrochemistry

MCM-41/vinylidine fluoride-hexafluropropene copolymer (PVdF-HFP) composite microporous polymer electrolytes were prepared with mixed solvent of N, N-Dimethylformamide (DMF) and acetone. The influence of MCM-41 and nano-SiO_(2) on the porous structure of the microporous polymer electrolytes were studied with SEM. The results show that MCM-41 could take the place of the plasticizer in the process of making pores, and bring the preparation of microporous membranes easily. The preliminary electrochemical tests showed that the ion conductivity of composite microporous polymer electrolyte with 10% MCM-41 was about 10~(-3) S cm~(-1), and the performance of batteries was improved. The mesoporous MCM-41selected in the paper possesses …

Study On Synthesis Of M-Phenoxy Benzoic Acid By Electrolysis Oxidation Method, Wei Xu, Chong-Tao Zhao

Journal of Electrochemistry

The m-phenoxy benzoic acid was synthesized by oxidation m-phenoxy toluene using Cr(Ⅵ)as oxidation media, which was prepared by electrolysis oxidation of Cr(Ⅲ)in the electrochemical bath using Nafion 417 as a diaphragm, Pb-PbO_(2) as an anode and Pb as cathode. The effect factors on the electrochemical oxidation of Cr(Ⅲ)to Cr(Ⅵ)in this electrolysis were studied. Furthermore, the optimal conditions for electronic synthesis of m-phenoxy benzoic acid were also discussed.

The Preparation And Performance Of The Aqueous Matrix For Molten Carbonate Fuel Cells, Hua-Xin Lin

Journal of Electrochemistry

PVA matrix of MCFC was prepared from the α-LiAlO_(2 )powder, and polyvinylalcohol(PVA), Compared with the conventional PVB matrix, higher porosity,higher thermal weight loss and smaller maximum pore diameter were achieved for PVA matrix. Single cell was assembled with PVA matrix. At reaction gas pressure of 0.9MPa, under reaction gas utilization of 20%, at 300 and 428.57mA·cm~(-2), the cell voltage was 0.849 and (0.739) V respectively, and the output power density was 254.7 and 316.7mW·cm~(-2 )respectively, which are higher than those of the cell assembled with PVB matrix. During thermal cycles, the cell performance shows a slightly decreasing-rising-stabilizing process, which might …

Investigation On Ru-Ti-Ir-Sn Oxide Anode Coatings For Electrolyzing Seawater, Wang Ke

Journal of Electrochemistry

The anode coatings of Ru-Ti-Ir-Sn oxide with various compositions were prepared by thermal decomposition. The physical and electrochemical properties of the coatings were characterized by scanning electron microscope (SEM), energy dispersive X-ray detector (EDX), accelerated life, current efficiency, anti-Mn~(2+)contamination, polarization curveandcyclic voltammetry tests. The results showed thatthe anode coating with optimized formula possessed excellent overall properties for electrolyzing seawater.

The Synthesis, Characteristics And Performance Of Cnt Composites As Anodic Materials In Litium-Ion Battery, Quan-Feng Dong, Ming-Sen Zheng, Zhen-Cai Huang, Ming-Gang Jin, Ya-Ding Zhan, Zu-Geng Lin

Journal of Electrochemistry

As an anodic material for lithium ion battery the carbon nano-tube (CNT) and some compounds based on tin have ever been investigated intensively. The fruited progress has not been made yet, however. In this paper the composites of CNT and Sn/SnO_(2)were synthesized employing two methods and characterized by SEM and XRD. And the electrochemical performance of the composites was investigated.

An Evaluation Of Wind Turbine Technology At Peterson Afb, Randy C. Combs

Theses and Dissertations

Wind energy technology is a viable source for attaining the emission reduction and renewable energy use goals set forth by the executive office. In accordance with Executive Orders, the Air Force must reduce greenhouse emissions and energy consumption, and expand the use of renewable energy sources within its facilities nation-wide by year 2010. This mandate requires that the Air Force look at alternative electrical production and rely more on such renewable energy resources as wind power. The specific problem addressed by this research is whether on-site wind energy generation can be more economically feasible than the conventional energy consumption at …

Studies On Polymer Light-Emitting Electrochemical Cells ——Introduction Of The Studies On The Electrochemistry Of Conducting Polymers In Cas Key Laboratory Of Organic Solids (Ⅱ), Yong-Fang Li

Journal of Electrochemistry

Polymer light-emitting electrochemical cell (LEC) is composed of a conjugated polymer(CP) / polymer electrolyte blend film sandwiched between an ITO anode and an Al cathode. When a bias voltage greater than Eg/e (where Eg is the energy gap of the CP, e is the electron charge) is applied on the two electrodes, the CP in the polymer blend film at the anode side will be oxidized (to form a p-doped region), and that at the cathode side will be reduced (to form a n-doped region), then a p-i-n junction will be produced. Light-emission occurs in the intrinsic region between the …

A Study Of Metal Borides As High Capacity Anode Materials For Aqueous Primary Batteries, Ya-Dong Wang, Xin-Ping Ai, Han-Xi Yang

Journal of Electrochemistry

The transition metal borides VB_2 and TiB_2 were tested as high capacity anode materials and their electrochemical behaviors were studied by cyclic voltammetry and discharge measurements. The experimental results indicated that transition metal borides VB_2 and TiB_2 electrodes can deliver exceptionally high discharge capacity of over 3100 mAH/g and 1 600 mAH/g respectively, corresponding to 11- and 6-electron oxidation reaction, although their parent elements V, Ti and boron, are almost completely electrochemically inert. The different electrochemical activitis were probably due to the electrochemical activation of boron, which clamp the potential to passivation for Ti and activity for V.

Influence Of Rare Earth Oxide On The Performance Of Secondary Zinc Electrodes, Xian-Ling Meng, Hua-Bin Yang, Jun-Hong Wang, Zuo-Xiang Zhou

Journal of Electrochemistry

Influence of La(OH)_(3 )or Ce(OH)_3in secondary zinc electrode was investigated by the cyclic voltammetry, potentiodynamic polarizationand potentiostatic polarization tests and influence of La_2O_3or CeO_2in the charge/discharge performance of Zn/Ni battery was studied by galvanostatic charge/discharge experiment. The results showed that the film of rare earth hydroxide prevented the zincate species from transferring toward solution, enhanced hydrogen overpotential and decreased thecorrosion current density (i_(corr)), and therefore inhibited zinc corrosion. The potentiostatic polarization results at100mV overpotential showed thatLa(OH)_3or Ce(OH)_3coated on the zinc electrode effectively suppressed the zinc dendrite growth. The La_2O_(3 )or CeO_2addition to the calcium zincate electrode improved the cycle performance …

Preparation And Characterization Of Lini_(0.85)Co_(0.10)(Timg)_(0.025)O_2 As Cathode Materials For Lithium-Ion Batteries, Xian-Jun Zhu, Hong-Hao Chen, Hui Zhan, Dai-Ling Yang, Yun-Hong Zhou

Journal of Electrochemistry

Cathode material of LiNi_(0.85)Co_(0.10)(TiMg)_(0.025)O_2 were prepared by solid state reaction at 725℃ for 24 h from LiOH·H_2O, Ni_2O_3, Co_2O_3, TiO_2 and Mg(OH)_2 under flowing oxygen, and were characterized by TG-DTA, XRD, SEM and electrochemical tests. Effort to simultaneously doped LiNiO_2 with Co-Ti-Mg has been tried to improve the cathode performance. The results show that co-doping definitely has a large beneficial effect in increasing the capacity (182.7mAh/g of the first discharge capacity for LiNi_(0.85)Co_(0.10)(TiMg)_(0.025)O_2) and cycling behavior (175.5 mAh/g after 10 cycles). This cathode materials can be applied for lithium-ion batteries.