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Sample records for prepare dense electrolyte

  1. Preparation of electrolyte membranes for micro tubular solid oxide fuel cells

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Yttria-stabilized zirconia (YSZ) micro tubular electrolyte membranes for solid oxide fuel cells (SOFCs) were prepared via the combined wet phase inversion and sintering technique. The as-derived YSZ mi- cro tubes consist of a thin dense skin layer and a thick porous layer that can serve as the electrode of fuel cells. The dense and the porous electrolyte layers have the thickness of 3-5 μm and 70-90 μm, respectively, while the inner surface porosity of the porous layer is higher than 28.1%. The two layers are perfectly integrated together to preclude the crack or flake of electrolyte film from the electrode. The presented method possesses distinct advantages such as technological simplicity, low cost and high reliability, and thus provides a new route for the preparation of micro tubular SOFCs.

  2. Dry processing versus dense medium processing for preparing thermal coal

    CSIR Research Space (South Africa)

    De Korte, GJ

    2013-10-01

    Full Text Available in the region. In addition to not requiring water, the technique is less expensive than dense medium processing - both in terms of capital cost and operating cost. An added benefit when preparing coal for use in power stations is the lower moisture content...

  3. A novel method for preparation of high dense tetragonal Li7La3Zr2O12

    Science.gov (United States)

    Zhao, Pengcheng; Wen, Yuehua; Cheng, Jie; Cao, Gaoping; Jin, Zhaoqing; Ming, Hai; Xu, Yan; Zhu, Xiayu

    2017-03-01

    For conventional preparation methods of Li7La3Zr2O12 (LLZO) solid state electrolytes, there is a stereotype that higher density always comes from higher pressure enforced upon the LLZO pellets. In this paper, a different way with an auto-consolidation mechanism is provided and discussed. No pressing operations are employed during the whole preparation process. Due to the surface tension of liquid melted Li2O at sintering temperature, LLZO particles could aggregate together freely and automatically. The preparation process for dense LLZO is greatly simplified. A dense tetragonal LLZO with high relative density about 93% has been prepared successfully by this auto-consolidation method. And there are no voids observed in the SEM images. At 30 °C, the total conductivity is about 5.67 × 10-5 S cm-1, which is the highest one for tetragonal LLZO in the reported issues, even two times higher than that prepared by hot-pressing method. The activation energy for total conductivity is ∼0.35 eV atom-1 at 30-120 °C, slightly lower than the previous reported values. This work sheds light on the understanding of the consolidation mechanism for solid electrolytes and suggests a reliable route to syhthesize cemanic solid electrolytes.

  4. Fabrication of thin yttria-stabilized-zirconia dense electrolyte layers by inkjet printing for high performing solid oxide fuel cells

    DEFF Research Database (Denmark)

    Esposito, Vincenzo; Gadea, Christophe; Hjelm, Johan

    2015-01-01

    In this work, we present how a low-cost HP Deskjet 1000 inkjet printer was used to fabricate a 1.2 mm thin, dense and gas tight 16 cm2 solid oxide fuel cells (SOFC) electrolyte. The electrolyte was printed using an ink made of highly diluted (...) powders (50 nm in size) in an aqueous medium. The ink was designed to be a highly dispersed, long term stable colloidal suspension, with optimal printability characteristics. The electrolyte was made by a multiple printing procedure, which ensures coverage of the several flaws occurring in a single...... printing pass. Together with an optimized sintering procedure this resulted in good adhesion and densification of the electrolyte. The SOFC exhibited a close-to-theoretical open circuit voltage and a remarkable peak power density above 1.5 W cm-2 at 800 °C....

  5. Studies on Electrolytic preparation of Iron Copper Powders

    Directory of Open Access Journals (Sweden)

    S. V. Athvale

    1971-07-01

    Full Text Available Factors affecting the physical characteristics and chemical composition of iron-cooper powder deposits obtained by electrolysis, have been investigated. Effect of process variables such as current density, pH, temperature, time, concentration of electrolyte and agitation, has been studied over a wide range, for theoretical interest and to obtain powder deposits of a definite composition. Metallographic examination of iron-copper powder thus prepared after compacting and sintering, has revealed uniform and homogeneous dispersion of the two metals. The technique of preparation presented in this paper is a better substitute to the conventional practice of preparing binary metal powders by mixing and tumbling.

  6. Solid State Electrolytes Prepared from PEO (360) Silanated Silica

    Science.gov (United States)

    Maitra, P.; Ding, J.; Liu, B.; Wunder, S. L.; Lin, H.-P.; Chua, D.; Salomon, M.

    2002-01-01

    All solid state composite electrolytes were prepared using fumed silica (SiO2) silanated with an oligomeric polyethylene oxide (PEO) silane containing 6-9 ethylene oxide repeat units, a PEO matrix and LiClO4 (8/1 O/Li). The PEO-silane covalently attached to the silica was amorphous, with a T(sub g) that increased from -90 C to -53 C after attachment. The conductivity of films prepared using the PEO-silanated silica increased to approx. 6 x 10(exp -5) S/cm at RT compared with approx. 1 x 10(-5) S/cm for films prepared with unsilanated SiO2.

  7. PREPARATION AND CHARACTERIZATION OF AMIDATED PECTIN BASED POLYMER ELECTROLYTE MEMBRANES

    Institute of Scientific and Technical Information of China (English)

    R.K.Mishra; A.Anis; S.Mondal; M.Dutt; A.K.Banthia

    2009-01-01

    The work presents the synthesis and characterization of ami dated pectin(AP)based polymer electrolyte membranes(PEM)crosslinked with glutaraldehyde(GA).The prepared membranes are characterized by Fourier transform infrared spectroscopy(FTIR),organic elemental analysis,X-ray diffraction studies(XRD),thermogravimetric analysis (TGA)and impedance spectroscopy.Mechanical properties of the membranes are evaluated by tensile tests.The degree of amidation(DA),molar and mass reaction yields(YM and YN)are calculated based on the results of organic elemental analysis.FTIR spectroscopy indicated the presence of primary and secondary amide absorption bands.XRD pattern of membranes clearly indicates that there is a considerable increase in crystallinity as compared to parent pectin.TGA studies indicate that AP is less thermally stable than reference pectin.A maximum room temperature conductivity of 1.098×10-3 Scm-1 is obtained in the membrane,which is designated as AP-3.These properties make them good candidates for low cost biopolymer electrolyte membranes for fuel cell applications.

  8. PREPARATION AND CHARACTERIZATION OF SOLID ELECTROLYTES: FUEL CELL APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Rambabu Bobba; Josef Hormes; T. Wang; Jaymes A. Baker; Donald G. Prier; Tommy Rockwood; Dinesha Hawkins; Saleem Hasan; V. Rayanki

    1997-12-31

    The intent of this project with Federal Energy Technology Center (FETC)/Morgantown Energy Technology Center (METC) is to develop research infrastructure conductive to Fuel Cell research at Southern University and A and M College, Baton Route. A state of the art research laboratory (James Hall No.123 and No.114) for energy conversion and storage devices was developed during this project duration. The Solid State Ionics laboratory is now fully equipped with materials research instruments: Arbin Battery Cycling and testing (8 channel) unit, Electrochemical Analyzer (EG and G PAR Model 273 and Solartron AC impedance analyzer), Fuel Cell test station (Globe Tech), Differential Scanning Calorimeter (DSC-10), Thermogravimetric Analyzer (TGA), Scanning Tunneling Microscope (STM), UV-VIS-NIR Absorption Spectrometer, Fluorescence Spectrometer, FT-IR Spectrometer, Extended X-ray Absorption Fine Structure (EXAFS) measurement capability at Center for Advanced Microstructure and Devices (CAMD- a multimillion dollar DOE facility), Glove Box, gas hood chamber, high temperature furnaces, hydraulic press and several high performance computers. IN particular, a high temperature furnace (Thermodyne 6000 furnace) and a high temperature oven were acquired through this project funds. The PI Dr. R Bobba has acquired additional funds from federal agencies include NSF-Academic Research Infrastructure program and other DOE sites. They have extensively used the multimillion dollar DOE facility ''Center'' for Advanced Microstructures and Devices (CAMD) for electrochemical research. The students were heavily involved in the experimental EXAFS measurements and made use of their DCM beamline for EXAFS research. The primary objective was to provide hands on experience to the selected African American undergraduate and graduate students in experimental energy research.The goal was to develop research skills and involve them in the Preparation and Characterization of Solid

  9. Preparation and Characterization of Organic-Inorganic Hybrid Hydrogel Electrolyte Using Alkaline Solution

    Directory of Open Access Journals (Sweden)

    Masanobu Chiku

    2011-09-01

    Full Text Available Organic-inorganic hybrid hydrogel electrolytes were prepared by mixing hydrotalcite, cross-linked potassium poly(acrylate and 6 M KOH solution. The organic-inorganic hybrid hydrogel electrolytes had high ionic conductivity (0.456–0.540 S cm−1 at 30 °C. Moreover, the mechanical strength of the hydrogel electrolytes was high enough to form a 2–3 mm thick freestanding membrane because of the reinforcement with hydrotalcite.

  10. Composition and particle size of electrolytic copper powders prepared in water-containing dimethyl sulfoxide electrolytes

    Science.gov (United States)

    Mamyrbekova, Aigul'; Abzhalov, B. S.; Mamyrbekova, Aizhan

    2017-07-01

    The possibility of the electroprecipitation of copper powder via the cathodic reduction of an electrolyte solution containing copper(II) nitrate trihydrate and dimethyl sulfoxide (DMSO) is shown. The effect electrolysis conditions (current density, concentration and temperature of electrolyte) have on the dimensional characteristics of copper powder is studied. The size and shape of the particles of the powders were determined by means of electron microscopy; the qualitative composition of the powders, with X-ray diffraction.

  11. Field assisted sintering of dense Al-substituted cubic phase Li7La3Zr2O12 solid electrolytes

    Science.gov (United States)

    Zhang, Yanhua; Chen, Fei; Tu, Rong; Shen, Qiang; Zhang, Lianmeng

    2014-12-01

    High performance lithium ion conducting Li7La3Zr2O12 solid electrolytes are prepared for the first time by field assisted sintering technology (FAST). The effect of sintering temperature on the phase compositions, microstructure and Li ionic conductivity is systematically investigated. The results show that pure cubic phase LLZO can be obtained at a range of temperatures from 1100 to 1180 °C for no more than 10 min. For the sample sintered at 1150 °C, a maximum relative density of 99.8% with a total ionic conductivity as high as 5.7 × 10-4 S cm-1 are obtained at room temperature. This value is the highest among the present research. Compared with the traditional preparation methods, the current FAST is very promising to obtain high performance LLZO for its advantages of very short sintering time, a single preparation step of reaction-densification processing, and relatively lower sintering temperature.

  12. Effects of current density on preparation of grainy electrolytic manganese dioxide

    Institute of Scientific and Technical Information of China (English)

    GUO Hua-jun; ZHU Bing-quan; LI Xin-hai; ZHANG Xin-ming; WANG Zhi-xing; PENG Wen-jie; LIU Lu-ping

    2005-01-01

    Grainy electrolytic manganese dioxide was prepared by electrodeposition in a 0.9 mol/L MnSO4 and 2.5 mol/L H2SO4 solution. The structure, particle size and appearance of the grainy electrolytic manganese dioxide were determined by powder X-ray diffraction, laser particle size analysis and scanning electron micrographs measurements. Current density has important effects on cell voltage, anodic current efficiency and particle size of the grainy electrolytic manganese dioxide, and the optimum current density is 30 A/dm 2. The grainy electrolytic manganese dioxide electrodeposited under the optimum conditions consists of γ-MnO2 with an orthorhombic lattice structure; the grainy electrolytic manganese dioxide has a spherical or sphere-like appearance and a narrow particle size distribution with an average particle diameter of 7.237 μm.

  13. Preparation and characterization of plasticized high molecular weight PVC-based polymer electrolytes

    Indian Academy of Sciences (India)

    S Ramesh; Geok Bee Teh; Rong-Fuh Louh; Yong Kong Hou; Pung Yen Sin; Lim Jing Yi

    2010-02-01

    Poly(vinyl chloride) (PVC)-based polymer electrolytes films consisting of lithium trifluromethanesulfonate (LiCF3SO3)-ethylene carbonate (EC) were prepared by the solution-casting method. Ionic conductivities of the electrolytes have been determined by an impedance studies in the temperature range of 298–373 K. Complexation of the prepared electrolytes is studied by X-ray diffraction (XRD) analysis. Thermogravimetric analysis (TGA) was used to confirm the thermal stability of the polymer electrolytes. The conductivity–temperature plots were found to follow an Arrhenius nature. All these films are found to be thermally stable until 132–167°C.

  14. Preparation of YSZ solid electrolyte by slip casting and its properties

    Institute of Scientific and Technical Information of China (English)

    DOU Jing; LI Heping; XU Liping; ZHANG Lei; WANG Guangwei

    2009-01-01

    Fully stabilized YSZ solid electrolyte was prepared by slip casting. The density was measured according to the Archimedes principle and the linear shrinkage was calculated from measuring the sizes of samples before and after sintering. XRD analysis was conducted to verify the phase structure of both the starting YSZ powder and the prepared YSZ electrolyte. The microstructure of fracture surface and the electrical properties of the samples sintered at different temperatures were investigated via SEM and a complex impedance method, respectively. By comparison of the properties and features among the samples, a slip casting method was established to be a simple way to manufacture high-quality YSZ electrolyte at the sintering temperature of 1550℃ for 3 h, which provides a new approach for YSZ electrolyte with com-plex shapes and mass production.

  15. Solid lithium ion conducting electrolytes and methods of preparation

    Science.gov (United States)

    Narula, Chaitanya K; Daniel, Claus

    2013-05-28

    A composition comprised of nanoparticles of lithium ion conducting solid oxide material, wherein the solid oxide material is comprised of lithium ions, and at least one type of metal ion selected from pentavalent metal ions and trivalent lanthanide metal ions. Solution methods useful for synthesizing these solid oxide materials, as well as precursor solutions and components thereof, are also described. The solid oxide materials are incorporated as electrolytes into lithium ion batteries.

  16. Performance of flexible capacitors based on polypyrrole/carbon fiber electrochemically prepared from various phosphate electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Wei; Han, Gaoyi, E-mail: han_gaoyis@sxu.edu.cn; Chang, Yunzhen; Li, Miaoyu; Xiao, Yaoming, E-mail: ymxiao@sxu.edu.cn; Zhou, Haihan; Zhang, Ying; Li, Yanping

    2016-11-30

    Highlights: • PPy/CFs have been fabricated by electrodepositing polypyrrole on carbon fibers. • The electrolytes in deposition solution have effect on PPy/CFs’ capacitive behavior. • Cells of PPy/CFs obtained from NaH{sub 2}PO{sub 4} electrolyte has good stability in PVA/H{sub 3}PO{sub 4}. - Abstract: In order to investigate the influence of electrolytes in electro-deposition solution on the capacitive properties of polypyrrole (PPy), we have chosen phosphoric acid, phosphate, hydrogen phosphate and dihydrogen phosphate as electrolyte in deposition solution respectively and electrochemically deposited PPy on carbon fibers (CFs) via galvanostatic method. The morphologies of the PPy/CFs samples have been characterized by scanning electron microscope. The specific capacitance of PPy/CFs samples has been evaluated in different electrolytes through three-electrode test system. The assembled flexible capacitors by using PPy/CFs as electrodes and H{sub 3}PO{sub 4}/polyvinyl alcohol as gel electrolyte have been systematically measured by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. The results show that the electrochemical capacitors based on PPy/CFs prepared from deposition solution containing NaH{sub 2}PO{sub 4}·2H{sub 2}O electrolyte exhibit higher specific capacitance, flexibility and excellent stability (retaining 96.8% of initial capacitance after 13,000 cycles), and that three cells connected in series can power a light-emitting diode.

  17. Preparation and characterization of nanocomposite polymer electrolytes poly(vinylidone fluoride)/nanoclay

    Energy Technology Data Exchange (ETDEWEB)

    Rahmawati, Suci A.; Sulistyaningsih,; Putro, Alviansyah Z. A.; Widyanto, Nugroho F.; Jumari, Arif; Purwanto, Agus; Dyartanti, Endah R., E-mail: endahrd@uns.ac.id [Research Group of Battery & Advanced Material, Department of Chemical Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A Kentingan, Surakarta Indonesia 57126 (Indonesia)

    2016-02-08

    Polymer electrolytes are defined as semi solid electrolytes used as separator in lithium ion battery. Separator used as medium for transfer ions and to prevent electrical short circuits in battery cells. To obtain the optimal battery performance, separator with high porosity and electrolyte uptake is required. This can reduce the resistance in the transfer of ions between cathode and anode. The main objective of this work is to investigate the impact of different solvent (Dimethyl acetamide (DMAc), N-methyl-2-pyrrolidone (NMP) and dimethyl formamide (DMF)), pore forming agent poly(vinylpyrolidone) (PVP) and nanoclay as filler in addition of membrane using phase inversion method on the morphology, porosity, electrolyte uptake and degree of crystallinity. The membrane was prepared by the phase inversion method by adding PVP and Nanoclay using different solvents. The phase inversion method was prepared by dissolving Nanoclay and PVP in solvent for 1-2 hours, and then add the PVDF with stirring for 4 hours at 60°C. The membranes were characterized by porosity test, electrolyte uptake test, scanning electron microscope (SEM), and X-ray diffraction (XRD). The results showed that DMAc as solvent gives the highest value of porosity and electrolyte uptake. The addition of nanoclay and PVP enlarge the size of the pores and reduce the degree of crystallinity. So, the usage of DMAc as solvent is better than NMP or DMF.

  18. Preparation and Characterization of Plasma Electrolytic Oxidation Coating on 5005 Aluminum Alloy with Red Mud as an Electrolyte Additive

    Science.gov (United States)

    Liu, Shifeng; Zeng, Jianmin; Wang, Youbin

    2017-10-01

    A coating with red mud as an electrolyte additive was applied to 5005 aluminum alloy using plasma electrolytic oxidation (PEO). The phase composition of the coating was investigated using X-ray diffraction. Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) was used to determine the microstructure and composition profiles of the coating. The coating/substrate adhesion was determined by scratch testing. The corrosion behaviors of the substrate and coating were evaluated using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The results indicated that the PEO coating with red mud consisted mainly of α-Al2O3 and γ-Al2O3, with small amounts of Fe2O3, CaCO3, and CaTiO3. The surface of the coating was the color of the red mud. The coating had a uniform thickness of about 80 μm and consisted of two main layers: a 6- μm porous outer layer and a 74- μm dense inner layer, which showed typical metallurgical adhesion (coating/substrate adhesion strength of 59 N). The coating hardness was about 1142 HV, much higher than that of the substrate (60 HV). The corrosion potential E corr and corrosion current density i corr of the coating were estimated to be -0.743 V and 3.85 × 10-6 A cm-2 from the PDP curve in 3.5 wt pct NaCl solution, and the maximum impedance and phase angle of the coating were 11 000 Ω and -67 deg, respectively, based on EIS. PEO coating with red mud improved the surface properties and corrosion resistance of 5005 aluminum alloy. This study also shows a potential method for reusing red mud.

  19. Preparation and Application of Nano-composite Poly(vinyl alcohol) Gel Electrolyte in Electrochemical Capacitor

    Institute of Scientific and Technical Information of China (English)

    陈赟; 谭强强; 徐宇兴

    2012-01-01

    A nano-composite polymer gel electrolyte was prepared using titanium oxide nanowire,poly(vinyl alcohol) (PVA),lithium salt and organic solvent N-methyl-2-pyrrolidone (NMP).The obtained electrolyte has the potential for application in electrochemical capacitor,the PVA in it is in an amorphous state.The ionic conductivities of electrolytes increased after addition of the nanowire,and the electrolyte with 3%(ω) of nanowire exhibited the highest ionic conductivity of 3.2 mS/cm at 20 ℃,as measured by electrochemical impedance spectroscopy.The temperature dependence of the conductivity was found to be in agreement with the Arrhenius equation.Functioning as separator and electrolyte,this nano-composite PVA gel electrolyte was used to assemble the electrochemical capacitor with active carbon film as electrodes.The compositing of nanowire may extend the life of electrochemical capacitors as they keep more than 90% of their capacitance after 5 000 cycles of charging and discharging.

  20. Electrolytic preparation of Al-Ca master alloy on liquid Al cathode

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    As a newly developing superplastic aluminum alloy, Al-Ca alloy has been widely used in industry, however thetechnology for preparing Al-Ca master alloy and its influencing factors need to be further studied. Therefore the Al-Camaster alloy was prepared by using liquid aluminum cathode and a mixture of 80%CaC12-18% KC1-2%CaF2 as the moltensalt electrolysis in a laboratory electrolyte cell; the effects of electrolysis temperature, cathodic current density and electrolytic duration on current efficiency and Ca content of Al-Ca alloy as well were studied. Through laboratory experiments, the parameters for smooth electrolytic reaction were proposed. The proper electrolysis technology is as follows:with the 80%CaCl2-18%KCl-2%CaF2 electrolyte, the electrolytic temperature is 973 K and the cathodic current densityis 0.8 A/cm2, the electrolysis can go on smoothly and a calcium content of 17.5%(mass fraction) can be obtained. Withthe increase of electrolysis duration, the calcium content in the alloy increasas whereas the current efficiency decreases

  1. Antibacterial efficiencies of TiO2 nanostructured layers prepared in organic viscous electrolytes

    Science.gov (United States)

    Dumitriu, Cristina; Popescu, Marian; Ungureanu, Camelia; Pirvu, Cristian

    2015-06-01

    Using easy and cheap potential step anodization in electrolytes with different molar mass and water content, a Ti substrate was covered with a nanostructured TiO2 layer. Surface characterization of the prepared samples was conducted using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and contact angle analysis. The formation mechanism and surface morphologies are very different, depending on the molar mass and water percent of electrolyte solutions used for anodizing Ti substrate. The electrochemical behavior of the samples was studied using Tafel plots, and electrochemical impedance spectroscopy recorded in a simulated body fluid. All used anodizing treatments have conducted to samples with increased corrosion protection. The paper illustrates the antibacterial efficiencies of TiO2 nanostructured layers (shielded nanotubes, nanoporous oxide layer and some remaining PEG electrolyte) quantitatively estimated using gram-negative bacterium Escherichia coli ATCC 8738.

  2. A Limiting Current Oxygen Sensor Based on LSGM as a Solid Electrolyte and LSGMN ( N = Fe, Co) as a Dense Diffusion Barrier

    Science.gov (United States)

    Liu, Tao; Gao, Xiang; He, Bei-Gang; Yu, Jing-Kun

    2016-07-01

    The La0.8Sr0.2(Ga1- x Co x )0.8Mg0.2O3- δ (LSGMC x = 0.05, 0.1, 0.15, 0.2, 0.25) and La0.8Sr0.2(Ga1- x Fe x )0.8Mg0.2O3- δ (LSGMF x = 0.1, 0.2, 0.3) samples were prepared by solid-state reaction. The structure, conductivity, thermal expansion behavior, and chemical compatibility were studied by XRD, dilatometry, and four-terminal method. A limiting current oxygen sensor was prepared with La0.8Sr0.2Ga0.83Mg0.17O2.815 as a solid electrolyte and La0.8Sr0.2(Ga0.75Co0.25)0.8Mg0.2O3- δ as a dense diffusion barrier. The oxygen-sensitive characteristic was measured at different oxygen concentrations. The results show that the phase structure of samples is cubic, except La0.8Sr0.2(Ga0.75Co0.25)0.8Mg0.2O3- δ , which has a hexagonal structure. The change in activation energy for electrical conductivity and the increase in thermal expansion coefficient are confirmed to correlate with an increasing concentration of oxygen vacancies. The limiting current oxygen sensor exhibits a good limiting current platform and the limiting current depends linearly on the oxygen concentration: I L(mA) = 12.8519 + 2.2667 x_{{{O}_{{2}} }} (mol%, 0 < x_{{{{O}}_{ 2} }} < 3.31) at 750 °C, I L(mA) = 14.3222 + 3.5180 x_{{{O}_{{2}} }} (mol%, 0 < x_{{{{O}}_{ 2} }} < 4.16) at 800 °C, and I L(mA) = 15.2872 + 5.0269x_{{{O}_{{2}} }}(mol%, 0 < x_{{{{O}}_{ 2} }} < 4.12) at 850 °C. The sensor has the best sensitivity at 850 °C. As the oxygen concentration increases, the interface resistance of the sensor decreases at 850 °C.

  3. High Lithium Transference Number Electrolytes via Creation of 3-Dimensional, Charged, Nanoporous Networks from Dense Functionalized Nanoparticle Composites

    KAUST Repository

    Schaefer, Jennifer L.

    2013-03-26

    High lithium transference number, tLi+, electrolytes are desired for use in both lithium-ion and lithium metal rechargeable battery technologies. Historically, low tLi+ electrolytes have hindered device performance by allowing ion concentration gradients within the cell, leading to high internal resistances that ultimately limit cell lifetime, charging rates, and energy density. Herein, we report on the synthesis and electrochemical features of electrolytes based on nanoparticle salts designed to provide high tLi+. The salts are created by cofunctionalization of metal oxide nanoparticles with neutral organic ligands and tethered lithium salts. When dispersed in a conducting fluid such as tetraglyme, they spontaneously form a charged, nanoporous network of particles at moderate nanoparticle loadings. Modification of the tethered anion chemistry from -SO3 - to -SO3BF3 - is shown to enhance ionic conductivity of the electrolytes by facilitating ion pair dissociation. At a particle volume fraction of 0.15, the electrolyte exists as a self-supported, nanoporous gel with an optimum ionic conductivity of 10 -4 S/cm at room temperature. Galvanostatic polarization measurements on symmetric lithium metal cells containing the electrolyte show that the cell short circuit time, tSC, is inversely proportional to the square of the applied current density tSC ∼ J-2, consistent with previously predicted results for traditional polymer-in-salt electrolytes with low tLi+. Our findings suggest that electrolytes with tLi+ ≈ 1 and good ion-pair dissociation delay lithium dendrite nucleation and may lead to improved lithium plating in rechargeable batteries with metallic lithium anodes. © 2013 American Chemical Society.

  4. A novel composite microporous polymer electrolyte prepared with molecule sieves for Li-ion batteries

    Science.gov (United States)

    Jiang, Yan-Xia; Chen, Zuo-Feng; Zhuang, Quan-Chao; Xu, Jin-Mei; Dong, Quan-Feng; Huang, Ling; Sun, Shi-Gang

    Molecular sieves of NaY, MCM-41, and SBA-15 were used as fillers in a poly(vinylidene fluoride- co-hexafluoropropylene) (PVdF-HFP) copolymer matrix to prepare microporous composite polymer electrolyte. The SBA-15-based composite polymer film was found to show rich pores that account for an ionic conductivity of 0.50 mS cm -1. However, the MCM-41 and NaY composite polymer films exhibited compact structure without any pores, and the addition of MCM-41 even resulted in aggregation of fillers in the polymer matrix. These differences were investigated and interpreted by their different compatibility with DMF solvent and PVdF-HFP matrix. Results of linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) have revealed that the addition of SBA-15 has extended the electrochemical stability window of polymer electrolyte, enhanced the interfacial stability of polymer electrolyte with lithium electrode, and inhibited also the crystallization of PVdF-HFP matrix. Half-cell of Li/SBA-15-based polymer electrolyte/MCF was assembled and tested. The results have demonstrated that the coulombic efficiency of the first cycle was around 87.0% and the cell remains 94.0% of the initial capacity after 20 cycles, which showed the potential application of the composite polymer electrolyte in lithium ion batteries.

  5. A novel composite microporous polymer electrolyte prepared with molecule sieves for Li-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Yan-Xia; Chen, Zuo-Feng; Zhuang, Quan-Chao; Xu, Jin-Mei; Dong, Quan-Feng; Huang, Ling; Sun, Shi-Gang [State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, 422, South Road of Siming, Xiamen 361005 (China)

    2006-10-06

    Molecular sieves of NaY, MCM-41, and SBA-15 were used as fillers in a poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) copolymer matrix to prepare microporous composite polymer electrolyte. The SBA-15-based composite polymer film was found to show rich pores that account for an ionic conductivity of 0.50mScm{sup -1}. However, the MCM-41 and NaY composite polymer films exhibited compact structure without any pores, and the addition of MCM-41 even resulted in aggregation of fillers in the polymer matrix. These differences were investigated and interpreted by their different compatibility with DMF solvent and PVdF-HFP matrix. Results of linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) have revealed that the addition of SBA-15 has extended the electrochemical stability window of polymer electrolyte, enhanced the interfacial stability of polymer electrolyte with lithium electrode, and inhibited also the crystallization of PVdF-HFP matrix. Half-cell of Li/SBA-15-based polymer electrolyte/MCF was assembled and tested. The results have demonstrated that the coulombic efficiency of the first cycle was around 87.0% and the cell remains 94.0% of the initial capacity after 20 cycles, which showed the potential application of the composite polymer electrolyte in lithium ion batteries. (author)

  6. Antibacterial efficiencies of TiO{sub 2} nanostructured layers prepared in organic viscous electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Dumitriu, Cristina [University Politehnica of Bucharest, 313 Splaiul Independentei, 060042 Bucharest (Romania); Popescu, Marian [University Politehnica of Bucharest, 313 Splaiul Independentei, 060042 Bucharest (Romania); National Institute for Research and Development in Microtechnologies, 126A, Erou Iancu Nicolae Street, 077190 Bucharest (Romania); Ungureanu, Camelia [University Politehnica of Bucharest, 313 Splaiul Independentei, 060042 Bucharest (Romania); Pirvu, Cristian, E-mail: c_pirvu@yahoo.com [University Politehnica of Bucharest, 313 Splaiul Independentei, 060042 Bucharest (Romania)

    2015-06-30

    Graphical abstract: - Highlights: • Ti substrate was covered with a nanostructured TiO{sub 2} layer in viscous electrolytes. • The formation mechanism and surface morphologies are very different. • The shielding covering the nanotubes incorporate the used electrolytes. • TiO{sub 2} nanostructured layers showed antibacterial efficiencies. - Abstract: Using easy and cheap potential step anodization in electrolytes with different molar mass and water content, a Ti substrate was covered with a nanostructured TiO{sub 2} layer. Surface characterization of the prepared samples was conducted using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and contact angle analysis. The formation mechanism and surface morphologies are very different, depending on the molar mass and water percent of electrolyte solutions used for anodizing Ti substrate. The electrochemical behavior of the samples was studied using Tafel plots, and electrochemical impedance spectroscopy recorded in a simulated body fluid. All used anodizing treatments have conducted to samples with increased corrosion protection. The paper illustrates the antibacterial efficiencies of TiO{sub 2} nanostructured layers (shielded nanotubes, nanoporous oxide layer and some remaining PEG electrolyte) quantitatively estimated using gram-negative bacterium Escherichia coli ATCC 8738.

  7. Performance of flexible capacitors based on polypyrrole/carbon fiber electrochemically prepared from various phosphate electrolytes

    Science.gov (United States)

    Yuan, Wei; Han, Gaoyi; Chang, Yunzhen; Li, Miaoyu; Xiao, Yaoming; Zhou, Haihan; Zhang, Ying; Li, Yanping

    2016-11-01

    In order to investigate the influence of electrolytes in electro-deposition solution on the capacitive properties of polypyrrole (PPy), we have chosen phosphoric acid, phosphate, hydrogen phosphate and dihydrogen phosphate as electrolyte in deposition solution respectively and electrochemically deposited PPy on carbon fibers (CFs) via galvanostatic method. The morphologies of the PPy/CFs samples have been characterized by scanning electron microscope. The specific capacitance of PPy/CFs samples has been evaluated in different electrolytes through three-electrode test system. The assembled flexible capacitors by using PPy/CFs as electrodes and H3PO4/polyvinyl alcohol as gel electrolyte have been systematically measured by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. The results show that the electrochemical capacitors based on PPy/CFs prepared from deposition solution containing NaH2PO4·2H2O electrolyte exhibit higher specific capacitance, flexibility and excellent stability (retaining 96.8% of initial capacitance after 13,000 cycles), and that three cells connected in series can power a light-emitting diode.

  8. Radiolytic preparation of PFA-g-PVBSA membranes as a polymer electrolyte membrane

    Energy Technology Data Exchange (ETDEWEB)

    Fei Geng [Department of Chemistry and Materials Engineering, Changshu Institute of Technology, Nansanhuan Road 99, Changshu, Jiangsu 215-500 (China); Hwang, Mi-Lim; Sohn, Joon-Yong; Nho, Young Chang [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongeup-si, Jeollabuk-do 580-185 (Korea, Republic of); Shin, Junhwa, E-mail: shinj@kaeri.re.kr [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongeup-si, Jeollabuk-do 580-185 (Korea, Republic of)

    2012-03-01

    In this study, a polymer electrolyte membrane, PFA-g-PVBSA was prepared through the radiation-induced graft copolymerization of vinylbenzyl chloride (VBC) monomer onto a poly(tetrafluoroethylene-co-perfluoropropylvinyl ether) (PFA) film and subsequent sulfonation processes. The IEC values and water uptakes of the prepared membranes increased when increasing the contents of the poly(vinylbenzyl sulfonic acid) (PVBSA) graft polymers in the membranes. Compared with Nafion 212, the degree of grafting (DOG) of membranes of 50% and 70% showed higher proton conductivity with significantly lower methanol permeability. The combination of these properties suggests that the prepared membranes are promising for future application in direct methanol fuel cells.

  9. Properties of Polymer Electrolyte Membranes Prepared by Blending of Sulfonated Polystyrene-Lignosulfonate

    Directory of Open Access Journals (Sweden)

    Siang Tandi Gonggo

    2012-11-01

    Full Text Available Electrolyte polymer membrane widely used in PEMFC and DMFC is a perfluorosulfonated membrane such as Nafion. This membrane material exhibits good chemical stability and proton conductivity, but it is very expensive and difficult to recycle. It has high cross-over methanol in DMFC that causes the decrease efficiency and performance of fuel cell, so that the electrolyte polymer membrane with low cross-over methanol has been needed to substitute Nafion membrane. One of the materials used as a polymer electrolyte membrane is polyblends of a sulfonated polystyrene-lignosulfonate (SPS-LS. These polyblends have been prepared by casting polymer solution and characterized as a polyelectrolyte membrane for DMFC. SPS was prepared by sulfonation of polystyrene with acetyl sulfate used as a sulfonating agent. The membranes of SPS-LS were characterized by analysis of functional groups, mechanical properties, and methanol permeability. The maximum mechanical properties of the SPS-LS membrane were observed in LS ratio of 7.5%. However, the methanol permeability of membrane increases as the increase of LS ratio in SPS-LS membranes. The properties of membranes, especially the mechanical property and methanol permeability close to that of Nafion® 117 membrane, so the SPS-LS membrane is highly potential used as the electrolyte membrane for direct methanol fuel cell.

  10. Preparation and Characterization of Lithium Ion Conducting Solid Polymer Electrolytes from Biodegradable Polymers Starch And PVA

    Directory of Open Access Journals (Sweden)

    B. Chatterjee,

    2015-06-01

    Full Text Available Solid Polymer electrolyte films have been prepared from Starch-Poly vinyl alcohol (PVA blend a well acknowledged biodegradable material. Solution cast technique was employed for the preparation of solid polymer electrolyte films added with Lithium Bromide (LiBr salt. X-ray diffraction (XRD studies of the prepared films portrayed the evolution of an amorphous structure with increasing content of salt which is an important factor that leads to the augmentation of conductivity. Electrochemical impedance spectroscopic analysis revealed noticeable ionic conductivity ~ 5x 10-3 S/cm for 20 wt% of salt at ambient conditions. Ionic conductivity showed an increasing trend with salt content at ambient conditions. Transference number measurements confirmed the ionic nature of the prepared solid polymer electrolyte films. Dielectric studies revealed a sharp increase in the number of charge carriers which contributed to enhancement in conductivity. Low values of activation energy extracted from temperature dependent conductivity measurements could be favorable for device applications. For the composition with highest conductivity a temperature independent relaxation mechanism was confirmed by electric modulus scaling.

  11. Preparation and electrical properties of dense micro-cermets made of nickel ferrite and metallic copper

    Science.gov (United States)

    Baco-Carles, Valérie; Pasquet, Isabelle; Laurent, Véronique; Gabriel, Armand; Tailhades, Philippe

    2009-08-01

    Dense micro-cermets made of nickel ferrites and copper micrometric particles were obtained from partial reduction under hydrogenated atmosphere at 350 °C of mixed copper nickel ferrites, and sintering in nitrogen at 980 °C. The small copper particles are homogeneous in size and well dispersed in the spinel oxide matrix. No exudation of copper metal was observed after sintering. The micro-cermets prepared are semi-conducting materials with electrical conductivity lying from 44 to 130 S/cm at 980 °C. Their overall characteristics make them interesting for inert anodes dedicated to aluminium electrolysis in melted cryolite.

  12. Preparation and characterization of a novel composite microporous polymer electrolyte for Li-ion batteries

    Institute of Scientific and Technical Information of China (English)

    CHEN Zuofeng; JIANG Yanxia; ZHUANG Quanchao; DONG Quanfeng; WANG Ye; SUN Shigang

    2005-01-01

    A novel composite microporous polymer electrolyte composed of poly(vinylidene fluoride-co-hexafluorop- ropylene) (PVdF-HFP) and mesoporous SBA-15 was prepared. The composite solid polymer electrolyte (CSPE) exhibits ionic conductivity as high as 0.30 mS·cm-1 with a composition of SBA-15:PVdF-HFP=3:8 at room temperature. Infrared transmission spectroscopic results suggested that the mechanism of micropore formation is similar to that of the phase inversion. X-ray diffraction (XRD) results demonstrated that the addition of SBA-15 inhibits the crystallization of PVdF-HFP, while the SBA-15 preserves well its ordered mesoporous structure during the course of preparation. The Li/CSPE/MCF of half-cell was assembled, and it showed a good electrochemical and cyclability performance during charge-discharge cycles.

  13. PREPARATION AND CHARACTERIZATION OF PVA BASED SOLID POLYMER ELECTROLYTES FOR ELECTROCHEMICAL CELL APPLICATIONS

    Institute of Scientific and Technical Information of China (English)

    Anji Reddy Polu; Ranveer Kumar

    2013-01-01

    Solid polymer electrolyte films containing poly(vinyl alcohol) (PVA) and magnesium nitrate (Mg(NO3)2) were prepared by solution casting technique and characterized by using XRD,FT1R,DSC and AC impedance spectroscopic analysis.The amorphous nature of the polymer electrolyte films has been confirmed by XRD.The complex formation between PVA and Mg salt has been confirmed by FTIR.The glass transition temperature decreases with increasing the Mg salt concentration.The AC impedance studies are performed to evaluate the ionic conductivity of the polymer electrolyte films in the range of 303-383 K,and the temperature dependence seems to obey the Arrhenius behavior.Transport number measurements show that the charge transport is mainly due to ions.Electrochemical cell of configuration Mg/(PVA + Mg(NO3)2) (70:30)/(I2 + C + electrolyte) has been fabricated.The discharge characteristics of the cell were studied for a constant load of 100 kΩ.

  14. Electrolyte Engineering Toward Efficient Hydrogen Production Electrocatalysis with Oxygen-crossover Regulation under Densely Buffered Near-neutral pH Conditions

    KAUST Repository

    Shinagawa, Tatsuya

    2015-12-30

    This study tackles the core issues associated with near-neutral pH water splitting, particularly regarding electrolyte engineering in the electrocatalysis and product cross-over. We demonstrate that solute engineering has a major impact on water splitting electrocatalysis because the diffusion component, often not well integrated into performance descriptions, largely determines the overall performance. The hydrogen evolution reaction (HER) was investigated on Pt, Ni and NiMo catalysts in various concentrations of cations (Li+, K+, Na+) and anions (H2PO4−, HPO42−, PO43− and HCO3−) to describe its performance by quantifying kinetics, diffusion and solution resistance. In fact, the choice of electrolyte in terms of its identity and activity drastically altered the HER rate and oxygen mass-transport flux at near-neutral pH. Electrolyte properties (activity coefficient, kinematic viscosity and diffusion coefficient) accurately described the diffusion contribution, which can be easily isolated when a highly active Pt catalyst was used for the HER. By analyzing these properties, we maximized the HER rate on the Pt by tuning the solute concentration (typically 1.5 – 2.0 M). Moreover, the kinematic viscosity and oxygen solubility in such densely buffered conditions governed the oxygen mass-transport flux in the electrolyte, which in turn tuned the cross-over flux. At near-neutral pH, as high as 90 % selectivity toward the HER was achieved even under an oxygen saturated condition, where only a 40 mV overpotential was needed to achieve 10 mA cm−2 for the HER. This information can be regarded as an important milestone for achieving a highly efficient water splitting system at near-neutral pH.

  15. Low temperature preparation and fuel cell properties of rare earth doped barium cerate solid electrolytes

    Institute of Scientific and Technical Information of China (English)

    蒋凯; 何志奇; 孟建; 任玉芳; 苏锵

    1999-01-01

    The solid electrolytes, BaCe0.8 Ln0.2O2.9 (Ln: Gd, Sm, Eu), were prepared by the sol-gel method. XRD indicated that a pure orthorhombic phase was formed at 900℃. The synthesis temperature by the sol-gel method was about 600℃ lower than the high temperature solid phase reaction method, The electrical conductivity and impedance spectra were measured and the conduction mechanism was studied. The grain-boundary resistance of the solid electrolyte could be reduced or eliminated by the sol-gel method. The conductivity of BaCe0.8Gd0.2O2.9 is 7.87×10-2 S·cm-1 at 800℃. The open-circuit voltage of hydrogen-oxygen fuel cell using BaCe0.8 Gd0.2O2.9 as electrolyte was near to 1 V and its maximum power density was 30 mW·cm-2.

  16. Microstructure, bonding strength and thermal shock resistance of ceramic coatings on steels prepared by plasma electrolytic oxidation

    Science.gov (United States)

    Wang, Yunlong; Jiang, Zhaohua; Yao, Zhongping

    2009-11-01

    Ceramic coatings were successfully prepared on steel by plasma electrolytic oxidation (PEO) in aluminate electrolyte and silicate electrolyte, respectively. The microstructure of the coatings including surface morphology, phase and element composition were studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The bonding strength between the ceramic coating and the substrate was tested using different methods including tensile tests and shearing tests. The thermal shock resistance of the coatings was also evaluated. The results indicated that coatings obtained in both electrolytes were porous and coarse. The average diameters of the pores were below 10 μm. PEO coatings obtained in aluminate electrolyte were composed of Fe 3O 4 and FeAl 2O 4, while those obtained in silicate electrolyte were in a noncrystal state. PEO coatings obtained in aluminate electrolyte showed similar change trend of tensile strength and shearing strength with increasing treating time, namely, a relatively high values with middle time treating and low value with short and long time treating. The best coating was the samples treated with 30 min, whose tensile strength was 20.6 MPa and shearing strength was 16 MPa. The tensile strength and shearing strength of coatings obtained in silicate electrolyte were not strongly influenced by the treating time, the values of which were range in 14 ± 2 MPa and 11 ± 2 MPa, respectively. Coatings obtained in both electrolytes showed the best thermal shock resistance with middle time treating. Coatings obtained in silicate electrolyte show a little better thermal shock resistance than those obtained in aluminate electrolyte.

  17. Ion transport in thin cell electrodeposition: modelling three-ion electrolytes in dense branched morphology under constant voltage and current conditions

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, G. [Courant Institute of Mathematical Sciences, New York University, New York, NY 10012 (United States) and Laboratorio de Sistemas Complejos, Departamento de Computacion, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, 1428 Buenos Aires (Argentina)]. E-mail: marshalg@mail.retina.ar; Molina, F.V. [INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, 1428 Buenos Aires (Argentina); Soba, A. [Laboratorio de Sistemas Complejos, Departamento de Computacion, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, 1428 Buenos Aires (Argentina)

    2005-05-30

    Electrochemical deposition (ECD) and spatially coupled bipolar electrochemistry (SCBE) experiments in thin-layer cells are known to produce complex ion transport patterns concomitantly with the growth of dendrite-like structures. Here we present a macroscopic model of ECD and SCBE with a three-ion electrolyte in conditions of dense branched morphology. The model describes ion transport and deposit growth through the one-dimensional Nernst-Planck equations for ion transport, the Poisson equation for the electric field and, for ECD, a growth law for deposit evolution. We present numerical simulations for typical electrochemical deposition experiments: dense branched morphology in ECD and the incubation period in SCBE. In ECD the model predicts cation, anion and proton concentration profiles, electric field variations and deposit growth speed, that are in qualitative agreement with experiments; the predicted evolution and collision of the deposit and proton fronts reveal a time scaling close to those observed in experiments. In SCBE, the model predicts that the inverse of the incubation time scales linearly with the applied voltage. Such behaviour was observed in experiments.

  18. Preparation of a Star Network PEG-based Gel Polymer Electrolyte and Its Application to Electrochromic Devices

    Institute of Scientific and Technical Information of China (English)

    GONG Yong-Feng; FU Xiang-Kai; ZHANG Shu-Peng; JIANG Qing-Long

    2007-01-01

    A star network polymer with a pentaerythritol core linking four PEG-block polymeric arms was synthesized,and its corresponding gel polymer electrolyte based on lithium perchlorate and plasticizers EC/PC with the character being colorless and highly transparent has been also prepared. The polymer host was characterized and confirmed to be of a star network and an amorphous structure by FTIR, 1H NMR and XRD studies. The polymer host hold good mechanical properties for pentaerythritol cross-linking. Maximum ionic conductivity of the prepared electrolyte showed that the thermal stability was up to at least 150 ℃. The gel polymer electrolyte was further evaluated in electrochromic devices fabricated by transparent PET-ITO and electrochromically active viologen derivative films, and its excellent performance promised the usage of the gel polymer electrolyte as ionic conductor material in electrochrornic devices.

  19. Application of Oral Lactulose in Combination With Polyethylene Glycol Electrolyte Powder for Colonoscopy Bowel Preparation in Patients With Constipation.

    Science.gov (United States)

    Lu, Juan; Cao, Qin; Wang, Xiaochun; Pu, Jianbin; Peng, Xuelian

    2016-01-01

    The aim of the study was to investigate the efficacy of combined application of lactulose oral solution and polyethylene glycol electrolyte powder compared with conventional method in preparing for colonoscopy bowel cleanliness in patients with constipation. Ninety patients, who had constipation and needed to have colonoscopy, were divided into study group and control group with 45 cases in each group, respectively. One day before the colonoscopy, patients in the experimental group were given lactulose oral solution and polyethylene glycol electrolyte powder, whereas the patients in the control group were given oral polyethylene glycol electrolyte powder only. The following parameters were then obtained: time of the first defecation (duration of the time from taking the drugs to the first bowel movement), defecation frequency, completion of bowel cleaning (duration from the first bowel movement to the stool becoming clear), and adverse reaction. Cleansing effect in the study group bowel preparation was significantly better than that in the control group (P 0.05). Combined application of lactulose oral solution and polyethylene glycol electrolyte powder is superior to the conventional method of polyethylene glycol electrolyte powder alone for colonoscopy bowel preparation in patients with constipation. Therefore, combined clinical application of the 2 compounds is strongly recommended for colonoscopy bowel preparation in patients with constipation.

  20. Porous shell/dense core structures prepared in tungsten phosphate glass through template-free route

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento Correa, Deleon; Alves, Oswaldo Luiz [Institute of Chemistry, University of Campinas - UNICAMP, Campinas, SP (Brazil); Odone Mazali, Italo, E-mail: mazali@iqm.unicamp.br [Institute of Chemistry, University of Campinas - UNICAMP, Campinas, SP (Brazil)

    2010-07-01

    The preparation of the 11.7Li{sub 2}O-39.7WO{sub 3}-10.9CaO-37.7P{sub 2}O{sub 5} glass (pgLWCP) was based on a one-step heat treatment of the 6Li{sub 2}O-18WO{sub 3}-43CaO-33P{sub 2}O{sub 5} (gLWCP) glass followed by leaching of the {beta}-Ca{sub 2}P{sub 2}O{sub 7} phase formed during the crystallization process. The porous structure was formed in the region formerly occupied by the {beta}-Ca{sub 2}P{sub 2}O{sub 7} phase. The gLWCP undergoes devitrification through surface crystallization. This process occurs after a thermal treatment in lower temperature and in a shorter period of time than that required for the complete crystallization. After acid leaching treatment, we obtained a core-/shell-like structure with a very well-defined dense glass (gLWCP)/porous glass (pgLWCP) interface. The pgLWCP exhibits reversible coloration-decoloration reactions.

  1. Preparation and characterization of dense graphite/glassy carbon composite coating for sealing application

    Science.gov (United States)

    Wang, Yang; Chen, Zhaofeng; Yu, Shengjie; Pan, Ning; Liao, Jiahao

    2017-09-01

    Glassy carbon (GC), characterized by a homogeneous structure and glass-like fracture surface once broken, has attracted increasing attention because of its excellent performance. In this paper, a dense graphite/glassy carbon composite coating with low gas permeability was introduced. In this composite coating, small graphite particles acting as second phase were wrapped by glassy carbon matrix. The composite coatings with different mass fractions of graphite particles were prepared. The mass loss of phenolic resin was determined by TG (thermogravimetry) analysis to determine the pyrolysis process. Raman spectrum analysis indicates that graphite content in composite coatings affected the G/D ratio significantly. The permeability of composite coatings with 50% and 100% graphite particles was almost same, which was ranged from 6  ×  10‑13 m3 · µm/m2 · s · Pa to 3  ×  10‑13 m3 · µm/m2 · s · Pa within the differential pressure from 100 kPa to 70 kPa. While the composite coating with 150% graphite particles had higher gas permeability due to the tiny micro-cracks and micro-pores produced. What was more, the densification mechanism of graphite/glassy carbon composite coating was also discussed in detail.

  2. Preparation and characterization of high salts polymer electrolyte based on poly(lithium acrylate)

    Institute of Scientific and Technical Information of China (English)

    TANG Ai-dong; HUANG Ke-long; PAN Chun-yue; LU Cui-hong

    2005-01-01

    Novel polymer electrolytes were prepared by highly mixing poly(lithium acrylate)(PPALi) with eutectic lithium salts of lithium acetate and lithium nitrate.Poly(lithium acrylate) was preparaed by inverse emulsion polymerization from crylic acid and LiOH.Phase transition temperatures were measured for all the eutectic lithium of binary system samples as a function of the concentration of Li(CH3 COO),and the mixtures exhibit the lowest phase transition temperatures of (448±2) K at about 50% (mass fraction) Li(CH3 COO).Thermogravimetry(TG)and X-ray diffraction(XRD) analysis indicate the formation of a novel polymer-salt complex.The highest conductivity(approximately 4.97 ×10-5S·cm-1) is found at room temperature with the electrolyte composition of eutectic mixture of about 80% (mass fraction),poly(lithium acrylate) 20% under quickly cooling condition,which is 150%higher than that under natural cooling condition.

  3. PREPARATION OF STAR NETWORK PEG-BASED GEL POLYMER ELECTROLYTES FOR ELECTROCHROMIC DEVICES

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An amorphous,colorless,and highly transparent star network polymer with a pentaerythritol core linking four PEG-block polymeric arms was synthesized from the poly(ethylene glycol)(PEG),pentaerythritol,and dichloromethane by Williamson reaction.FTIR and 1H-NMR measurement demonstrated that the polymer repeating units were C[CH2-OCH2O-(CH2CH2O)m-CH2O-(CH2CH2O)n-CH2O]4.The polymer host held well mechanical properties for pentaerythritol cross-linking.The gel polymer electrolytes based on Lithium perchlorate(LiClO4)and ethylene carbonate/propylene carbonate(EC/PC)were prepared and characterized by AC impedance spectroscopy and thermogravimetry(TG),the results showed thermal stability up to at least 150℃ and ionic conductivity reaching 8.83×fabricated by transparent PET-ITO and electrochromic active viologen derivative films,and its excellent performance promised the usage of the gel polymer electrolytes as ionic conductor material in ECD.

  4. One-step electrolytic preparation of Si-Fe alloys as anodes for lithium ion batteries

    Science.gov (United States)

    Wang, Hailong; Sun, Diankun; Song, Qiqi; Xie, Wenqi; Jiang, Xu; Zhang, Bo

    2016-06-01

    One-step electrolytic formation of uniform crystalline Si-Fe alloy particles was successfully demonstrated in direct electro-reduction of solid mixed oxides of SiO2 and Fe2O3 in molten CaCl2 at 900∘C. Upon constant voltage electrolysis of solid mixed oxides at 2.8V between solid oxide cathode and graphite anode for 5h, electrolytic Si-Fe with the same Si/Fe stoichimetry of the precursory oxides was generated. The firstly generated Fe could function as depolarizers to enhance reduction rate of SiO2, resulting in the enhanced reduction kinetics to the electrolysis of individual SiO2. When evaluated as anode for lithium ion batteries, the prepared SiFe electrode showed a reversible lithium storage capacity as high as 470mAh g-1 after 100 cycles at 200mA g-1, promising application in high-performance lithium ion batteries.

  5. Bowel preparation in CT colonography: electrolyte and renal function disturbances in the frail and elderly patient

    Energy Technology Data Exchange (ETDEWEB)

    Mc Laughlin, Patrick; Mc Sweeney, Sean; Mc Williams, Sebastian; O' Regan, Kevin; Kelly, Denis; Maher, Michael M. [Cork University Hospital, Department of Radiology, Cork (Ireland); Eustace, Joseph; O' Connor, Michael [Cork University Hospital, Department of Medicine, Cork (Ireland)

    2010-03-15

    Elderly patients are at increased risk of biochemical disturbances secondary to cathartic medications. This study investigates the renal function, electrolyte and clinical disturbances associated with CT colonography (CTC) with sodium picosulphate-magnesium citrate (SPS-MC) in a subgroup of frail, elderly patients. Patients aged over 70 years considered at risk of complication during SPS-MC administration by a physician specialised in care of the elderly were included in this retrospective study. Biochemical parameters pre- and post-CTC and the presence of co-morbidities were recorded. Imaging findings and quality of bowel preparation at CTC were graded by consensus by two radiologists. Of the 72 patients 56% had co-morbidities that caution the use of SPS-MC. No significant changes in serum urea, sodium, potassium or estimated glomerular filtration rate (eGFR) occurred post-CTC (p > 0.10). Serum magnesium increased by 0.11 mmol/L in 14 patients (p = 0.03) without clinical sequelae. Good overall preparation was achieved in 88% of patients, allowing confident identification of signs of colonic neoplasia in 20 patients (27%). A mild increase in serum magnesium but no other significant biochemical disturbance was observed. In our group CTC with SPS-MC was safe and effective; however, we advise an alternate preparation be considered in patients with decreased renal function due to decreased magnesium clearance. (orig.)

  6. Colonoscopy Preparation: Polyethylene Glycol with Gatorade is as Safe and Efficacious as 4 Liters of Polyethylene Glycol with Balanced Electrolytes

    Science.gov (United States)

    McKenna, Thomas; Macgill, Alice; Porat, Gail; Friedenberg, Frank K.

    2013-01-01

    Background Four liters of polyethylene glycol 3350 with balanced electrolytes for colonoscopy preparation has had poor acceptance. Another approach is the use of electrolyte-free PEG combined with 1.9L of Gatorade. Despite its widespread use, there are no data on metabolic safety and minimal data on efficacy. Our aim was to assess the efficacy and electrolyte safety of these two PEG-based preparations. Methods This was a prospective, randomized, single-blind, non-inferiority trial. Patients were randomized to 238g PEG + 1.9L Gatorade or 4L of PEG-ELS containing 236g PEG. Split dosing was not performed. On procedure day blood was drawn for basic chemistries. The primary outcome was preparation quality from procedure photos using the Boston Bowel Preparation Scale. Results We randomized 136 patients (66 PEG + Gatorade, 70 PEG-ELS). There were no differences in preparation scores between the two agents in the ITT analysis (7.2 ± 1.9 for PEG-ELS and 7.0 ± 2.1 for PEG + Gatorade; p = 0.45). BBPS scores were identical for those who completed the preparation and dietary instructions as directed (7.4 ± 1.7 for PEG-ELS, and 7.4 ± 1.8 for PEG + Gatorade; p = 0.98). There were no statistical differences in serum electrolytes between the two preparations. Patients who received PEG + Gatorade gave higher overall satisfaction scores for the preparation experience (p = 0.001), and had fewer adverse effects. Conclusions Use of 238g PEG + 1.9L Gatorade appears to be safe, better tolerated, and non-inferior to 4L PEG-ELS. This preparation may be especially useful for patients who previously tolerated PEG-ELS poorly. PMID:22711499

  7. Colonoscopy preparation: polyethylene glycol with Gatorade is as safe and efficacious as four liters of polyethylene glycol with balanced electrolytes.

    Science.gov (United States)

    McKenna, Thomas; Macgill, Alice; Porat, Gail; Friedenberg, Frank K

    2012-12-01

    Four liters of polyethylene glycol 3350 (PEG) with balanced electrolytes for colonoscopy preparation has had poor acceptance. Another approach is the use of electrolyte-free PEG combined with 1.9 L of Gatorade. Despite its widespread use, there are no data on metabolic safety and minimal data on efficacy. Our aim was to assess the efficacy and electrolyte safety of these two PEG-based preparations. This was a prospective, randomized, single-blind, non-inferiority trial. Patients were randomized to 238 g PEG + 1.9 L Gatorade or 4 L of PEG-ELS containing 236 g PEG. Split dosing was not performed. On procedure day blood was drawn for basic chemistries. The primary outcome was preparation quality from procedure photos using the Boston Bowel Preparation Scale. We randomized 136 patients (66 PEG + Gatorade, 70 PEG-ELS). There were no differences in preparation scores between the two agents in the ITT analysis (7.2 ± 1.9 for PEG-ELS and 7.0 ± 2.1 for PEG + Gatorade; p = 0.45). BBPS scores were identical for those who completed the preparation and dietary instructions as directed (7.4 ± 1.7 for PEG-ELS, and 7.4 ± 1.8 for PEG + Gatorade; p = 0.98). There were no statistical differences in serum electrolytes between the two preparations. Patients who received PEG + Gatorade gave higher overall satisfaction scores for the preparation experience (p = 0.001), and had fewer adverse effects. Use of 238 g PEG + 1.9 L Gatorade appears to be safe, better tolerated, and non-inferior to 4 L PEG-ELS. This preparation may be especially useful for patients who previously tolerated PEG-ELS poorly.

  8. Ion conducting solid polymer electrolytes based on polypentafluorostyrene-b-polyether-b-polypentafluorostyrene prepared by atom transfer radical polymerization

    DEFF Research Database (Denmark)

    Jankova, Katja; Jannasch, P.; Hvilsted, Søren

    2004-01-01

    .3. The bromoisobutyrate functionalized polyether macroinitiators with molecular masses (M-n) of approx. 10 000 enabled the addition of between 15 and 39 wt.% flanking PFS as found by H-1 NMR. In a similar fashion monomethoxy PEG ( MPEG, Mn 5 000) was added 50 wt.% PFS. Polymer electrolytes were prepared by complexing...

  9. UV-Induced Radical Photo-Polymerization: A Smart Tool for Preparing Polymer Electrolyte Membranes for Energy Storage Devices

    Directory of Open Access Journals (Sweden)

    Claudio Gerbaldi

    2012-06-01

    Full Text Available In the present work, the preparation and characterization of quasi-solid polymer electrolyte membranes based on methacrylic monomers and oligomers, with the addition of organic plasticizers and lithium salt, are described. Noticeable improvements in the mechanical properties by reinforcement with natural cellulose hand-sheets or nanoscale microfibrillated cellulose fibers are also demonstrated. The ionic conductivity of the various prepared membranes is very high, with average values approaching 10-3 S cm-1 at ambient temperature. The electrochemical stability window is wide (anodic breakdown voltages > 4.5 V vs. Li in all the cases along with good cyclability in lithium cells at ambient temperature. The galvanostatic cycling tests are conducted by constructing laboratory-scale lithium cells using LiFePO4 as cathode and lithium metal as anode with the selected polymer electrolyte membrane as the electrolyte separator. The results obtained demonstrate that UV induced radical photo-polymerization is a well suited method for an easy and rapid preparation of easy tunable quasi-solid polymer electrolyte membranes for energy storage devices.

  10. UV-Induced Radical Photo-Polymerization: A Smart Tool for Preparing Polymer Electrolyte Membranes for Energy Storage Devices

    Directory of Open Access Journals (Sweden)

    Claudio Gerbaldi

    2012-10-01

    Full Text Available In the present work, the preparation and characterization of quasi-solid polymer electrolyte membranes based on methacrylic monomers and oligomers, with the addition of organic plasticizers and lithium salt, are described. Noticeable improvements in the mechanical properties by reinforcement with natural cellulose hand-sheets or nanoscale microfibrillated cellulose fibers are also demonstrated. The ionic conductivity of the various prepared membranes is very high, with average values approaching 10-3 S cm-1 at ambient temperature. The electrochemical stability window is wide (anodic breakdown voltages > 4.5 V vs. Li in all the cases along with good cyclability in lithium cells at ambient temperature. The galvanostatic cycling tests are conducted by constructing laboratory-scale lithium cells using LiFePO4 as cathode and lithium metal as anode with the selected polymer electrolyte membrane as the electrolyte separator. The results obtained demonstrate that UV induced radical photo-polymerization is a well suited method for an easy and rapid preparation of easy tunable quasi-solid polymer electrolyte membranes for energy storage devices.

  11. Preparation and characterization of a mixing soft-segment waterborne polyurethane polymer electrolyte

    Institute of Scientific and Technical Information of China (English)

    Feng Wu; Yue JiaoLi; Ren Jie Chen; Shi Chen

    2009-01-01

    The mixing soft-segment WPU (waterborne polyurethane) polymer electrolytes were synthesized by using PEO (poly(ethylene oxide)) and PDMS (polydimethylsiloxane) as the soft segments. These polymer electrolytes exhibit good thermal and electro-chemical stability. The conductivity of the gel polymer electrolyte is 2.52×10-3 S/cm at 25 ℃ with the LiTFSI/(DMC + EC) content of 130%.

  12. Preparation of porous, chemically cross-linked, PVdF-based gel polymer electrolytes for rechargeable lithium batteries

    Science.gov (United States)

    Cheng, C. L.; Wan, C. C.; Wang, Y. Y.

    This study reports the development of a new system of porous, chemically cross-linked, gel polymer electrolytes based on poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) copolymer as a polymer matrix, polyethylene glycol (PEG) as a plasticizer, and polyethylene glycol dimethacrylate (PEGDMA) as a chemical cross-linking oligomer. The electrolytes are prepared by a combination of controlled evaporation and thermal polymerization of PEGDMA. PVdF-HFP/PEG/PEGDMA gel polymer electrolytes with a composition of 5/3/2 exhibit both high ambient ionic conductivity, viz., >1 mS cm -1, and a high tensile modulus of 52 MPa, because of their porous and network structures. All the blends of electrolytes are electrochemically stable up to 5 V versus Li/Li + in the presence of 1 M LiPF 6/ethylene carbonate-diethyl carbonate (EC-DEC). With these polymer electrolytes, rechargeable lithium batteries composed of carbon anode and LiCoO 2 cathode have acceptable cycleability and a good rate capability.

  13. Preparation and Characterization of a Hybrid Solid Polymer Electrolyte Consisting of Poly(Ethyleneoxide) and Poly(Acrylonitrile) for Polymer-Battery Application

    OpenAIRE

    Nookala, Munichandraiah; Scanlon, Lawrence G; Marsh, Richard A

    1997-01-01

    For application in an ambient temperature solid state lithium battery a highly dimensionally-stable polymer electrolyte based on polyethyleneoxide (PEO) suffers from low ionic conductivity, whereas a highly conducting gel electrolyte based on polyacrylonitrile (PAN) suffers from low dimensional stability. In order to overcome these problems, a hybrid solid polymer electrolyte (HSPE) was prepared using PEO, PAN, propylene carbonate (PC), ethylene carbonate (EC) and lithium perchlorate. The HSP...

  14. STUDY ON THE PREPARATION AND PERFORMANCES OF P(VAc-MMA) POLYMER ELECTROLYTES FOR LITHIUM ION BATTERY

    Institute of Scientific and Technical Information of China (English)

    Dao-jun Yang; Xiang-kai Fu; Yong-feng Gong

    2008-01-01

    A random copolymer P(VAc-MMA) was synthesized via seeded emulsion copolymerization with vinyl acetate (VAc) and methyl methacrylate (MMA) as monomers, and the polymer electrolytes comprising blend of corresponding copolymer P(VAc-MMA) as a host polymer and LiC104 as a dopant were prepared by solution casting technique. Performances of the synthesized copolymer and prepared polymer membrane and electrolyte were studied by FTIR, XRD, TG, DSC, mechanical testing and AC impedance. According to the study of FTIR and DSC, it was found that P(VAc-MMA) had been formed. XRD indicates that the amorphous nature in copolymer increased with increasing the ratio of VAc in monomers, resulting in expedite migration of ions. The polymer electrolytes based on P(VAc-MMA) possess excellent thermal stability, fine mechanical performance and high ionic conductivity. The maximum ionic conductivity value was found to reach 1.27 × 10-3S·cm-1 at 25℃. The temperature dependence of the polymer electrolyte complexes appeared to obey Arrhenius equation.

  15. Preparation and characterization of plasticized palm-based polyurethane solid polymer electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Daud, Farah Nadia; Ahmad, Azizan; Badri, Khairiah Haji [School of Chemical Science and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan (Malaysia)

    2013-11-27

    Palm-based polyurethane solid polymer electrolyte was prepared via prepolymerization method between palm kernel oil based polyols (PKO-p) and 2,4’-diphenylmethane diisocyanate (2,4’-MDI) in acetone at room temperature with the vary amount of lithium trifuoromethanesulfonate (LiCF{sub 3}SO{sub 3}) salt and polyethylene glycol (PEG). The film was analyzed using attenuated total reflection infrared (ATR-IR) spectroscopy, electrochemical impedance spectroscopy (EIS) and X-ray diffractometry (XRD). EIS result indicated ionic conductivity obtained with 30 wt% LiCF3SO3 increased to 6.55 × 10{sup −6} S cm{sup −1} when 10 wt.% of plasticizer was added into the system. FTIR analysis showed the interaction between lithium ions and amine (-N-H) at 3600–3100 cm{sup −1}, carbonyl (-C=O) at 1750–1650 cm{sup −1} and ether (-C-O-C-) at 1150–1000 cm{sup −1} of the polyurethane forming polymer-salt complexes. The XRD result confirmed that LiCF{sub 3}SO{sub 3} salt completely dissociated within the polyurethane film with the absence of crystalline peaks of LiCF{sub 3}SO{sub 3}.

  16. Dense and Cellular Zirconia Produced by Gel Casting with Agar: Preparation and High Temperature Characterization

    Directory of Open Access Journals (Sweden)

    Jean-Marc Tulliani

    2013-01-01

    Full Text Available A modified gel-casting process was developed to produce both dense and highly porous (40% volume yttria tetragonal zirconia polycrystal (Y-TZP using agar, a natural polysaccharide, as gelling agent. A fugitive phase, made of commercial polyethylene spheres, was added to the ceramic suspension before gelling to produce cellular ceramic structures. The characterization of the microstructural features of both dense and cellular ceramics was carried out by FEG SEM analysis of cross-sections produced by focused ion beam. The mechanical properties of the components were characterized at room temperature by nanoindentation tests in continuous stiffness measurement mode, by investigating the direct effect of the presence of residual microporosity. The presence of a diffuse residual microporosity from incomplete gel deaeration resulted in a decay of the bending strength and of the elastic modulus. The mechanical behavior of both dense and cellular zirconia (in terms of elastic modulus, flexural strength, and deformation at rupture was investigated by performing four-point bending tests at the temperature of 1500°C.

  17. One-pot preparation of new copolymer electrolytes with tunable network structure for all-solid-state lithium battery

    Science.gov (United States)

    Chen, Bo; Xu, Qiang; Huang, Zhen; Zhao, Yanran; Chen, Shaojie; Xu, Xiaoxiong

    2016-11-01

    A new class of copolymer electrolytes with tunable network structure is successfully designed and prepared via a facile one-pot reaction. The trimethylolpropane triglycidyl ether (TMPEG) is cross-linked with poly (ethylene glycol) diamine (NPEG) to create well-defined solid network polymer electrolyte (SNPE). The network structure could be tuned by changing the molar ratio of TMPEG and NPEG or the molecular weight of NPEG. The effects of molecular weight of NPEG and molar ratio of EO/Li+ on the ionic conductivity are systematically investigated. The optimal electrolyte TMPEG-NPEG4K[2:1]-16:1 presents a maximum conductivity of 1.10 × 10-4 S cm-1 under 30 °C, and an 18-fold ionic conductivity enhancement in that of PEO-based electrolyte. Furthermore, it also exhibits wide electrochemical window (0-5.4 V), excellent compatibility with metallic Li, and superior mechanical properties. The all-solid-state lithium batteries LiFePO4/Li are assembled with TMPEG-NPEG4K[2:1]-16:1 electrolyte, and present good cycling and rate performance under 60 °C. The initial discharge specific capacities of the batteries are 161.7 mAh g-1 at 0.2 C and 132.7 mAh g-1 at 1 C, and the capacity retention ratio can be retained at 90.6% and 90.5% after 100 cycles. This new copolymer electrolyte may become a promising candidate for applications in all-solid-state lithium battery.

  18. Conditions for preparation of ultrapure beryllium by electrolytic refining in molten alkali-metal chlorides

    Energy Technology Data Exchange (ETDEWEB)

    Wohlfarth, Hagen

    1982-02-01

    Electrolytic refining is regarded as the most suitable process for the production of beryllium with impurity contents below 1 at.-ppM. Several parameters are important for electrolytic refining of beryllium in a BeCl/sub 2/-containing LiCl-KCl melt: current density, BeCl/sub 2/ content, electrolyte temperature, composition of the unpurified beryllium and impurity-ion concentrations in the melt, as well as apparatus characteristics such as rotation speed of the cathode and condition of the crucible material. These factors were studied and optimized such that extensive removal of the maximum number of accompanying and alloying elements was achieved.

  19. Preparation and characterization of PAN–KI complexed gel polymer electrolytes for solid-state battery applications

    Indian Academy of Sciences (India)

    N KRISHNA JYOTHI; K K VENKATARATNAM; P NARAYANA MURTY; K VIJAYA KUMAR

    2016-08-01

    The free standing and dimensionally stable gel polymer electrolyte films of polyacrylonitrile (PAN): potassium iodide (KI) of different compositions, using ethylene carbonate as a plasticizer and dimethyl formamide as solvent, are prepared by adopting ‘solution casting technique’ and these films are examined for their conductivities. The structural, miscibility and the chemical rapport between PAN and KI are investigated using X-ray diffraction, Fourier transform infrared spectroscopy and differential scanning calorimetry methods. The conductivity is enhanced with the increase in KI concentration and temperature. The maximum conductivity at 30$^{\\circ}$C is found to be $2.089 \\times 10^{−5}$ S cm$^{−1}$ for PAN:KI (70:30) wt%, which is nine orders greater than that of pure PAN (${\\lt}10^{−14}$ S cm$^{−1}$). The conductivity-temperature dependence of these polymer electrolyte films obeys Arrhenius behaviour with activation energy ranging from 0.358 to 0.478 eV. The conducting carriers of charge transport in these polymer electrolyte films are identified by Wagner’s polarization technique and it is found that the charge transport is predominantlydue to ions. The better conducting sample is used to fabricate the battery with configuration K/PAN $+$ KI/I$_2$ $+$ C $+$ electrolyte and good discharge characteristics of battery are observed.

  20. Preparation and corrosion resistance of a nanocomposite plasma electrolytic oxidation coating on Mg-1%Ca alloy formed in aluminate electrolyte containing titania nano-additives

    DEFF Research Database (Denmark)

    Daroonparvar, Mohammadreza; Yajid, M. A. M.; Yusof, N. M.

    2016-01-01

    Titania nanoparticles were utilized as suspension in alkaline aluminate electrolyte to form nanocomposite coatings on magnesium alloy containing 1 wt% calcium by plasma electrolytic oxidation process. Microhardness, wettability, potentiodynamic polarization, wettability, electrochemical impedance...

  1. Properties of Polymer Electrolyte Membranes Prepared by Blending of Sulfonated Polystyrene-Lignosulfonate

    OpenAIRE

    Siang Tandi Gonggo; Cynthia L. Radiman; Bunbun Bundjali; I Made Arcana

    2012-01-01

    Electrolyte polymer membrane widely used in PEMFC and DMFC is a perfluorosulfonated membrane such as Nafion. This membrane material exhibits good chemical stability and proton conductivity, but it is very expensive and difficult to recycle. It has high cross-over methanol in DMFC that causes the decrease efficiency and performance of fuel cell, so that the electrolyte polymer membrane with low cross-over methanol has been needed to substitute Nafion membrane. One of the materials used as a po...

  2. Preparation of poly(ether ether ketone)-based polymer electrolytes for fuel cell membranes using grafting technique

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, Shin; Suzuki, Yasuyuki [Conducting Polymer Materials Group, Environment and Industrial Materials Research Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370 1292 (Japan); Maekawa, Yasunari [Conducting Polymer Materials Group, Environment and Industrial Materials Research Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370 1292 (Japan)], E-mail: maekawa.yasunari@jaea.go.jp

    2008-05-15

    Poly(ether ether ketone) (PEEK)-based polymer electrolyte membranes (PEMs) was successfully prepared by radiation grafting of a styrene monomer into PEEK films and the consequent selective sulfonation of the grafting chains in the film state. Using milder sulfonation, the sulfonation reactions proceeded at the grafted chains in preference to the phenylene rings of PEEK main chains; as a result, the grafted films could successfully transform to a PEM with conductivity of more than 0.1 S/cm. The ion exchange capacity (IEC) and conductivity of the grafted PEEK electrolyte membranes were controlled to the ranges of 1.2-2.9 mmol/g and 0.03-0.18 S/cm by changing the grafting degree. It should be noted that this is the first example of directly transforming super-engineering plastic films into a PEM using radiation grafting.

  3. Influence of grafting solvents on the properties of polymer electrolyte membranes prepared by {gamma}-ray preirradiation method

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Yosuke [Department of Chemistry, Faculty of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376 8515 (Japan)], E-mail: yosuke.kimura@jaea.go.jp; Asano, Masaharu; Chen, Jinhua; Maekawa, Yasunari [Environment and Industrial Materials Research Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), 1233 Watanuki-machi, Takasaki, Gunma 370 1292 (Japan); Katakai, Ryoichi [Department of Chemistry, Faculty of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376 8515 (Japan); Yoshida, Masaru [Environment and Industrial Materials Research Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), 1233 Watanuki-machi, Takasaki, Gunma 370 1292 (Japan)

    2008-07-15

    The effect of grafting solvents, such as isopropanol (iPrOH), tetrachloroethane (TCE), tetrahydrofuran (THF), and toluene, on the preparation of poly(ethylene-co-tetrafluoroethylene)-graft-poly(styrene sulfonic acid) (ETFE-g-PSSA) electrolyte membranes by the {gamma}-ray preirradiation grafting method was investigated. It was found that the iPrOH can drastically accelerate the grafting, resulting in a higher degree of grafting. However, for an appropriate degree of grafting of about 50%, the sulfonic acid groups in the ETFE-g-PSSA membrane prepared with the iPrOH were mainly distributed near the membrane surface, as shown by low proton conductivity in the membrane thickness direction. In contrast to this result, the ETFE-g-PSSA membranes prepared with the THF, toluene and TCE exhibited uniform distribution of the sulfonic acid groups in the membrane. Especially, in the case of the TCE grafting solvent, the chemical stability of the resultant electrolyte membrane was clearly higher than those prepared with the other grafting solvents.

  4. Micromold methods for fabricating perforated substrates and for preparing solid polymer electrolyte composite membranes

    Energy Technology Data Exchange (ETDEWEB)

    Mittelsteadt, Cortney; Argun, Avni; Laicer, Castro; Willey, Jason

    2017-08-08

    In polymer electrolyte membrane (PEM) fuel cells and electrolyzes, attaining and maintaining high membrane conductivity and durability is crucial for performance and efficiency. The use of low equivalent weight (EW) perfluorinated ionomers is one of the few options available to improve membrane conductivity. However, excessive dimensional changes of low EW ionomers upon application of wet/dry or freeze/thaw cycles yield catastrophic losses in membrane integrity. Incorporation of ionomers within porous, dimensionally-stable perforated polymer electrolyte membrane substrates provides improved PEM performance and longevity. The present invention provides novel methods using micromolds to fabricate the perforated polymer electrolyte membrane substrates. These novel methods using micromolds create uniform and well-defined pore structures. In addition, these novel methods using micromolds described herein may be used in batch or continuous processing.

  5. Preparation and characterization of core-shell electrodes for application in gel electrolyte-based dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Avellaneda, Cesar O.; Goncalves, Agnaldo D.; Benedetti, Joao E. [Laboratorio de Nanotecnologia e Energia Solar (LNES), Instituto de Quimica, Universidade Estadual de Campinas - UNICAMP, P.O. Box 6154, 13083-970 Campinas/SP (Brazil); Nogueira, Ana F., E-mail: anaflavia@iqm.unicamp.b [Laboratorio de Nanotecnologia e Energia Solar (LNES), Instituto de Quimica, Universidade Estadual de Campinas - UNICAMP, P.O. Box 6154, 13083-970 Campinas/SP (Brazil)

    2010-01-25

    Core-shell electrodes based on TiO{sub 2} covered with different oxides were prepared and characterized. These electrodes were applied in gel electrolyte-based dye-sensitized solar cells (DSSC). The TiO{sub 2} electrodes were prepared from TiO{sub 2} powder (P25 Degussa) and coated with thin layers of Al{sub 2}O{sub 3}, MgO, Nb{sub 2}O{sub 5}, and SrTiO{sub 3} prepared by the sol-gel method. The core-shell electrodes were characterized by X-ray diffraction, scanning electron microscopy and atomic force microscopy measurements. J-V curves in the dark and under standard AM 1.5 conditions and photovoltage decay measurements under open-circuit conditions were carried out in order to evaluate the influence of the oxide layer on the charge recombination dynamics and on the device's performance. The results indicated an improvement in the conversion efficiency as a result of an increase in the open circuit voltage. The photovoltage decay curves under open-circuit conditions showed that the core-shell electrodes provide longer electron lifetime values compared to uncoated TiO{sub 2} electrodes, corroborating with a minimization in the recombination losses at the nanoparticle surface/electrolyte interface. This is the first time that a study has been applied to DSSC based on gel polymer electrolyte. The optimum performance was achieved by solar cells based on TiO{sub 2}/MgO core-shell electrodes: fill factor of approx0.60, short-circuit current density J{sub sc} of 12 mA cm{sup -2}, open-circuit voltage V{sub oc} of 0.78 V and overall energy conversion efficiency of approx5% (under illumination of 100 mW cm{sup -2}).

  6. Preparation of MnO2and calcium silicate hydrate from electrolytic manganese residue and evaluation of adsorption properties

    Institute of Scientific and Technical Information of China (English)

    李昌新; 钟宏; 王帅; 薛建荣; 武芳芳; 张振宇

    2015-01-01

    Electrolytic manganese residue (EMR), a high volume byproduct resulting from the electrolytic manganese industry, was used as a cheap and abundant chemical source for preparing MnO2 and EMR-made calcium silicate hydrate (EMR-CSH). The MnO2 is successfully synthesized from the metal cations extracted from EMR, which can effectively recycle the manganese in the EMR. By the combination of XRD, SEM and EDX analysis, the as-prepared MnO2 is found to exhibit a single-phase with the purity of 90.3%. Furthermore, EMR-CSH is synthesized from EMR via hydrothermal method. Based on the detailed analyses using XRD, FT-IR, FE-SEM, EDX and BET surface area measurement, the product synthesized under the optimum conditions (pH 12.0 and 100 °C) is identified to be a calcium silicate hydrate with a specific surface area of 205 m2/g incorporating the slag-derived metals (Al and Mg) in its structure. The as-synthesized material shows good adsorption properties for removal of Mn2+ and phosphate ions diluted in water, making it a promising candidate for efficient bulk wastewater treatment. This conversion process, which enables us to fabricate two different kinds of valuable materials from EMR at low cost and through convenient preparation steps, is surely beneficial from the viewpoint of the chemical and economical use of EMR.

  7. Bowel preparation in CT colonography: electrolyte and renal function disturbances in the frail and elderly patient.

    LENUS (Irish Health Repository)

    Mc Laughlin, Patrick

    2010-03-01

    Elderly patients are at increased risk of biochemical disturbances secondary to cathartic medications. This study investigates the renal function, electrolyte and clinical disturbances associated with CT colonography (CTC) with sodium picosulphate-magnesium citrate (SPS-MC) in a subgroup of frail, elderly patients.

  8. PREPARATION AND ELECTROCHEMICAL CHARACTERISTICS OF POLYMER ELECTROLYTE MEMBRANES BASED ON SAN/PVDF-HFP BLENDS

    Institute of Scientific and Technical Information of China (English)

    Ding-guo Tang; Lu Qi; Yun-xiang Ci

    2006-01-01

    A copolymer of poly(acrylonitrile-co-styrene) (SAN) was synthesized via an emulsion polymerization method.Novel polymer electrolyte membranes cast from the blends of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), SAN and fumed silica (SiO2) are microporous and can be used in polymer lithium-ion batteries. The membrane shows excellent characteristics such as high ionic conductivity and good mechanical strength when the mass ratio between SAN and PVDF-HFP and SiO2 is 3.5/31.5/5. The ionic conductivity of the membrane soaked in a liquid electrolyte of 1 mol/L LiPF6/EC/DMC/DEC is 4.9 × 10-3 Scm-1 at 25℃. The membrane is electrochemical stable up to 5.5 V versus Li+/Li in the liquid electrolyte. The influences of SiO2 content on the porosity and mechanical strength of the membranes were studied.Polymer lithium-ion batteries based on the membranes were assembled and their performances were also studied.

  9. Preparation and oxygen permeation properties of SrFe(Cu)O3-δ dense ceramic membranes

    Institute of Scientific and Technical Information of China (English)

    Heng Zhang; Tingting Wang; Xinfa Dong; Weiming Lin

    2009-01-01

    Mixed oxygen-ionic and electronic conducting membranes of SrFe(Cu)O3-δ were prepared by solid-state reaction method.The crystal structure,oxygen nonstoichiometry,and phase stability of the materials were studied by TGA and XRD.Oxygen permeation fluxes through these membranes were studied at operating temperature ranging from 750 to 950 ℃.Results showed that doping Cu in SrFeO3-δ compound had a significant effect on the formation of single-phased perovskite structure.For SrFe1-xCuxO3-δ series materials,the oxygen nonstoichiometry and the oxygen permeation flux increased considerably with the increase of Cu-doping content (x = 0.1-0.3).The sintering property of the membrane decreased significantly when the Cu substitution amount reached 40%.SrFe0.7CU0.3O3-δ showed high oxygen permeation flux,but SrCuO2 and Sr2Fe2O5 phases formed in the compound after oxygen permeation test induced cracks in the membrane.

  10. Porous-Al2O3 thermal barrier coatings with dispersed Pt particles prepared by cathode plasma electrolytic deposition

    Institute of Scientific and Technical Information of China (English)

    Jin Zhang

    2016-01-01

    Porousa-Al2O3 thermal barrier coatings (TBCs) containing dispersed Pt particles were prepared by cathode plasma electrolytic deposition (CPED). The influence of the Pt particles on the microstructure of the coatings and the CPED process were studied. The prepared coatings were mainly composed ofα-Al2O3. The average thickness of the coatings was approximately 100μm. Such single-layer TBCs ex-hibited not only excellent high-temperature cyclic oxidation and spallation resistance, but also good thermal insulation properties. Porousa-Al2O3 TBCs inhibit further oxidation of alloy substrates because of their extremely low oxygen diffusion rate, provide good thermal insu-lation because of their porous structure, and exhibit excellent mechanical properties because of the toughening effect of the Pt particles and because of stress relaxation induced by deformation of the porous structure.

  11. Highly efficient solid-state dye-sensitized solar cells based on hexylimidazolium iodide ionic polymer electrolyte prepared by in situ low-temperature polymerization

    Science.gov (United States)

    Wang, Guiqiang; Yan, Chao; Zhang, Juan; Hou, Shuo; Zhang, Wei

    2017-03-01

    Solid-state dye-sensitized solar cells (DSCs) are fabricated using a novel ionic polymer electrolyte containing hexylimidazolium iodide (HII) ionic polymer prepared by in situ polymerization of N,N‧-bis(imidazolyl) hexane and 1,6-diiodohexane without an initiator at low temperature (40 °C). The as-prepared HII ionic polymer has a similar structure to alkylimidazolium iodide ionic liquid, and the imidazolium cations are contained in the polymer main chain; so, it can act simultaneously as the redox mediator in the electrolyte. By incorporating an appropriate amount of 1,3-dimethylimidazolium iodide (DMII) in HII ionic polymer (DMII/HII ionic polymer = 0.7:1, weight ratio), the conductivity of the ionic polymer electrolyte is greatly improved due to the formation of Grotthuss bond exchange. In addition, in situ synthesis of ionic polymer electrolyte guarantees a good pore-filling of the electrolyte in the TiO2 photoanode. As a result, the solid-state DSC based on the ionic polymer electrolyte containing HII ionic polymer and DMII without iodine achieves a conversion efficiency of 6.55% under the illumination of 100 mW cm-2 (AM 1.5), which also exhibits a good at-rest stability at room temperature.

  12. Study of Sm0.2Ce0.8O1.9 (SDC) electrolyte prepared by a simple modified solid-state method

    Institute of Scientific and Technical Information of China (English)

    殷仕龙; 李梦楠; 曾燕伟; 李传明; 陈小卫; 叶祝鹏

    2014-01-01

    Sm0.2Ce0.8O1.9 (SDC) electrolyte was prepared by a modified solid state method at relatively low sintering temperatures without any sintering promoters. The phase composition and microstructure of the electrolytes were investigated by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) technologies. A relative density of SDC electrolyte sintered at 1300 ºC reached 97.3%and the mean SDC grain size was about 770 nm. Their ionic conductivity and thermal expansion coefficient were also measured by electrochemical workstation and dilatometer. The electrolyte attained a high conductivity of 5×10-2 S/cm at 800 ºC with an activation energy of 1.03 eV and a proper thermal expansion coefficient of 12.6×10-6 K-1.

  13. A UV-prepared linear polymer electrolyte membrane for dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Imperiyka, M., E-mail: imperiyka@gmail.com [Faculty of Arts and Sciences, Kufra Campus, University of Benghazi, Al Kufrah (Libya); Ahmad, A.; Hanifah, S.A. [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Polymer Research Center, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Bella, F. [Center for Space Human Robotics @Polito, Istituto Italiano di Tecnologia, Corso Trento 21, 10129 Torino (Italy); Department of Applied Science and Technology – DISAT, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy)

    2014-10-01

    The effects of LiClO{sub 4} and LiFS{sub 3}SO{sub 3} on poly(glycidyl methacrylate)-based solid polymer electrolyte and its photoelectrochemical performance in a dye sensitized solar cell consisting of FTO/TiO{sub 2}–dye/P(GMA)–LiClO{sub 4}–EC/Pt were investigated. The electrochemical stability of films was studied by cyclic voltammetry (CV). The highest ionic conductivities obtained were 4.2×10{sup −5} and 3.7×10{sup −6} S cm{sup −1} for the film containing 30 wt% LiClO{sub 4} and 25 wt% LiCF{sub 3}SO{sub 3}, respectively. The polymer electrolytes showed electrochemical stability windows up to 3 V and 2.8 V for LiClO{sub 4} and LiCF{sub 3}SO{sub 3}, respectively. The assembled dye-sensitized solar cell showed a sunlight conversion efficiency of 0.679% (J{sub sc}=3 mA cm{sup −2}, V{sub oc}=0.48 V and FF=0.47), under light intensity of 100 mW cm{sup −2}.

  14. Preparation and investigation of cheap polymer electrolyte membranes for fuel cells

    DEFF Research Database (Denmark)

    Larsen, Mikkel Juul; Ma, Yue; Lund, Peter Brilner

    The electrolyte of choice for low temperature polymer electrolyte fuel cells (PEFCs) has tra­di­ti­o­nal­ly been DuPontTM Nafion® membranes or similar poly(perfluorosulfonic acid)s. The chemical struc­ture and morphology in the hydrated state of Nafion® is shown in figure 1 from which it is seen...... found that crosslinking by divinylbenzene clear­ly improves the chemical stability of both sulfonated styrene- and methylstyrene/t-butylstyrene-grafted ETFE membranes. How­ever, the crosslinking reduces the proton conductivity due to decreased water uptake, thus downgrading the membranes' elec­tro­ly­tic.......; Schuster, M.; Chemical Reviews 104 (2004) 4637-4678 [ii] Skou, E.; Kauranen, P.; Hentschel, J.; Solid State Ionics 97 (1997) 333-337 [iii] Fuel Cell Handbook; Seventh Edition; EG&G Technical Services, Inc.; 2004; p. 3.1-3.25 [iv] Doyle, M.; Rajendran, G. in Handbook of Fuel Cells - Fundamentals, Technology...

  15. Preparation and investigation of cheap polymer electrolyte membranes for fuel cells

    DEFF Research Database (Denmark)

    Larsen, Mikkel Juul; Ma, Yue; Lund, Peter Brilner

    The electrolyte of choice for low temperature polymer electrolyte fuel cells (PEFCs) has tra­di­ti­o­nal­ly been DuPontTM Nafion® membranes or similar poly(perfluorosulfonic acid)s. The chemical struc­ture and morphology in the hydrated state of Nafion® is shown in figure 1 from which it is seen...... crossover, and relatively poor thermal stability constitute seri­ous drawbacks with respect to their fuel cell use.[ii],[iii],[iv] These aspects propel the search for cheaper and better alternatives.           In this study membrane systems consisting of a hydrophobic poly...... found that crosslinking by divinylbenzene clear­ly improves the chemical stability of both sulfonated styrene- and methylstyrene/t-butylstyrene-grafted ETFE membranes. How­ever, the crosslinking reduces the proton conductivity due to decreased water uptake, thus downgrading the membranes' elec­tro­ly­tic...

  16. Chemical and radiation crosslinked polymer electrolyte membranes prepared from radiation-grafted ETFE films for DMFC applications

    Science.gov (United States)

    Chen, Jinhua; Asano, Masaharu; Yamaki, Tetsuya; Yoshida, Masaru

    To develop a highly chemically stable polymer electrolyte membrane for application in a direct methanol fuel cell (DMFC), doubly crosslinked membranes were prepared by chemical crosslinking using bifunctional monomers, such as divinylbenzene (DVB) and bis(p, p-vinyl phenyl) ethane (BVPE), and by radiation crosslinking. The membranes were prepared by grafting of m, p-methylstyrene (MeSt) and p-tert-butylstyrene (tBuSt) into poly(ethylene- co-tetrafluoroethylene) (ETFE) films and subsequent sulfonation. The effects of the DVB and BVPE crosslinkers on the grafting kinetics and the properties of the prepared membranes, such as water uptake, proton conductivity and chemical stability were investigated. Radiation crosslinking was introduced by irradiation of the ETFE base film, the grafted film or the sulfonated membrane. The membrane crosslinked by DVB and BVPE crosslinkers and post-crosslinked by γ-ray irradiation of the corresponding grafted film possessed the highest chemical stability among the prepared membranes, a significantly lower methanol permeability compared to Nafion ® membranes, and a better DMFC performance for high methanol feed concentration. Therefore, this doubly crosslinked membrane was promising for application in a DMFC where relatively high methanol concentration could be fed.

  17. Chemical and radiation crosslinked polymer electrolyte membranes prepared from radiation-grafted ETFE films for DMFC applications

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jinhua; Asano, Masaharu; Yamaki, Tetsuya; Yoshida, Masaru [Department of Material Development, Takasaki Radiation Chemistry Research Establishment, Japan Atomic Energy Research Institute, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2006-07-14

    To develop a highly chemically stable polymer electrolyte membrane for application in a direct methanol fuel cell (DMFC), doubly crosslinked membranes were prepared by chemical crosslinking using bifunctional monomers, such as divinylbenzene (DVB) and bis(p,p-vinyl phenyl) ethane (BVPE), and by radiation crosslinking. The membranes were prepared by grafting of m,p-methylstyrene (MeSt) and p-tert-butylstyrene (tBuSt) into poly(ethylene-co-tetrafluoroethylene) (ETFE) films and subsequent sulfonation. The effects of the DVB and BVPE crosslinkers on the grafting kinetics and the properties of the prepared membranes, such as water uptake, proton conductivity and chemical stability were investigated. Radiation crosslinking was introduced by irradiation of the ETFE base film, the grafted film or the sulfonated membrane. The membrane crosslinked by DVB and BVPE crosslinkers and post-crosslinked by {gamma}-ray irradiation of the corresponding grafted film possessed the highest chemical stability among the prepared membranes, a significantly lower methanol permeability compared to Nafion{sup R} membranes, and a better DMFC performance for high methanol feed concentration. Therefore, this doubly crosslinked membrane was promising for application in a DMFC where relatively high methanol concentration could be fed. (author)

  18. Preparation and Characterization of Amorphous Layer on Aluminum Alloy Formed by Plasma Electrolytic Deposition (PED)

    Institute of Scientific and Technical Information of China (English)

    GUAN Yong-jun; XIA Yuan

    2004-01-01

    In this investigation, protective layers were formed on aluminum substrate by Plasma Electrolytic Deposition (PED) using sodium silicate solution. The relation between the thickness of the layer and process time were studied. XRD,SEM, EDS were used to study the layer's structure, composition and micrograph. The results show that the deposited layers are amorphous and contain mainly oxygen, silicon, and aluminum. The possible formation mechanism of amorphous [Al-Si-O] layer was proposed: During discharge periods, Al2O3 phase of the passive film and SiO32-near the substrate surface are sintered into xSiO2(1-x)Al2O3 and then transformed into amorphous [Al-Si-O] phase.

  19. A porous poly(vinylidene fluoride) gel electrolyte for lithium ion batteries prepared by using salicylic acid as a foaming agent

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, H.P. [Department of Material Science, Fudan University, Shanghai 200433 (China); Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433 (China); Zhang, P.; Li, G.C.; Wu, Y.P. [Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433 (China); Sun, D.L. [Department of Material Science, Fudan University, Shanghai 200433 (China)

    2009-04-01

    A porous gel polymer electrolyte based on poly(vinylidene fluoride) (PVDF) was for the first time prepared via a foaming technology using salicylic acid as a foaming agent. The pores are evenly distributed with an average diameter of about 400 nm. The results from TG/DTA, XRD and FT-IR show that there are no vesicant residues after the PVDF film was heat-treated at 200 C to get the porous structure. When the film is gelled with liquid electrolyte, the ion conductivity can be up to 4.8 x 10{sup -3} S cm{sup -1} at room temperature and the activation energy for ionic transfer is 10.2 kJ mol{sup -1}. LiCoO{sub 2} cathode also presents good cycling performance. These primary results show great promise for this simple method to prepare porous gel polymer electrolytes for practical application in lithium ion batteries. (author)

  20. Characteristics of PVdF-HFP/TiO{sub 2} composite membrane electrolytes prepared by phase inversion and conventional casting methods

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kwang Man; Ryu, Kwang Sun; Chang, Soon Ho [Ionics Devices Team, Basic Research Lab., Electronics and Telecommunications Research Institute (ETRI), 161 Gajong, Yusong, Daejon 305-700 (Korea, Republic of); Park, Nam-Gyu [Materials Science and Technology Division, Korea Institute of Science and Technology (KIST), 39-1 Hwaolgok, Seongbuk, Seoul 136-791 (Korea, Republic of)

    2006-08-15

    Porous poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP)-based polymer membranes filled with various contents of titania (TiO{sub 2}) nanocrystalline particles are prepared by phase inversion technique and, along with conventional casting method for comparison. N-methyl-2-pyrrolidone (NMP) as a solvent is used to dissolve the polymer and to make the slurry with TiO{sub 2}. Cast film is obtained by spreading the slurry and evaporating NMP in a dry oven, while phase inversion membrane by promptly immersing the spread slurry into flowing water as a non-solvent. Physical and electrochemical characterizations, such as morphology, thermal and crystalline behavior, and other transport properties of lithium ionic species, are carried out for the polymer films/membranes and the polymer electrolytes with absorbing an electrolyte solution. Phase inversion polymer electrolytes are proved to show superior behaviors in electrochemical properties, such as ionic conductivity, electrochemical and interfacial stability, than cast film electrolytes. This is greatly owed to highly porous structure of phase inversion membranes. Even including the feature of interfacial resistance with lithium electrode, phase inversion polymer electrolytes of PVdF-HFP/(5-20wt.% TiO{sub 2}) can be optimized as the adequate ones in applying to the electrolyte medium of lithium rechargeable batteries. (author)

  1. Anti-corrosion layer prepared by plasma electrolytic carbonitriding on pure aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jie; Zhang, Yifan; Liu, Run; Wang, Bin; Hua, Ming [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Xue, Wenbin, E-mail: xuewb@bnu.edu.cn [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2015-08-30

    Highlights: • PEC/N can be applied to low melting point metal. • The spectroscopic characterization of plasma discharge is investigated. • Electron concentration and electron temperature are evaluated for PEC/N. • Phase composition of the carbonitrided layer is determined. • PEC/N improves the corrosion resistance of aluminum greatly. - Abstract: In this paper, plasma electrolytic carbonitriding (PEC/N) method was applied to pure aluminum for the first time. The spectroscopic characterization of plasma discharge during PEC/N process was analyzed and the electron temperature was calculated in terms of optical emission spectroscopy. The results showed the discharge plasma was in local thermal equilibrium (LTE) state. Electron concentration and electron temperature were about 6 × 10{sup 21} m{sup −3} and 4000 K, respectively. The carbonitrided layer contained Al{sub 4}C{sub 3}, AlN and Al{sub 7}C{sub 3}N{sub 3} phases. After PEC/N treatment, the corrosion resistance of pure aluminum was significantly improved, which was related to the formation of nitride phases. This work expands the application of plasma electrolysis technology on the surface modification of low melting point metal.

  2. Preparation and Molten Salt as Performances of Room Electrolyte carbon Capacitor Based on Trifluoroacetamide n CarbonLiPF6 and

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    A novel room moRen salt with an eutectic temperature of about -62℃ is prepared using LiPF6 and trifluoroacetamide as precursors. And then its performance is evaluated in carbon-carbon electrochemical double layerdifferent molar ratios are characterized and then the liquid-solid phase diagram is presented. The electrochemical performance tests show that the as-prepared LiPF6/trifluoroacetamide molten salt is a promising electrolyte candidate for carboncarbon EDLCs.

  3. Nanoscale Organic Hybrid Electrolytes

    KAUST Repository

    Nugent, Jennifer L.

    2010-08-20

    Nanoscale organic hybrid electrolytes are composed of organic-inorganic hybrid nanostructures, each with a metal oxide or metallic nanoparticle core densely grafted with an ion-conducting polyethylene glycol corona - doped with lithium salt. These materials form novel solvent-free hybrid electrolytes that are particle-rich, soft glasses at room temperature; yet manifest high ionic conductivity and good electrochemical stability above 5V. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Study on Preparation and Electrical Properties of Ba1.03 Ce0.2O3-α Solid Electrolyte

    Institute of Scientific and Technical Information of China (English)

    仇立干; 马桂林; 闻荻江

    2004-01-01

    Ba1.03Ce0.8Eu0.2O3-α solid electrolyte with nonstoichiometric composition was prepared by high temperature solid-state reaction. Phase composition,surface and fracture morphologies of the specimen were characterized by using XRD and SEM,respectively. Ionic conduction was researched by gas concentration cell,the performance of hydrogen-air fuel cell was measured in the temperature range of 600~1000 ℃,and compared them with those of BaCe0.8Eu0.2O3-α and Ba0.98Ce0.8Eu0.2O3-α. The results indicate that Ba1.03Ce0.8Eu0.2O3-α is a single-phase perovskite-type orthorhombic system. It is a pure proton conductor in the temperature range of 600~1000 ℃ in hydrogen atmosphere,and its proton conduction is superior to that of BaCe0.8Eu0.2O3-α and Ba0.98Ce0.8Eu0.2O3-α. It is a mixed conductor of oxide ion and electron hole in oxygen atmosphere. At 1000 ℃,the performance of the fuel cell in which Ba1.03Ce0.8Eu0.2O3-α as electrolyte is higher than that of BaCe0.8Eu0.2O3-α or Ba0.98Ce0.8Eu0.2O3-α.

  5. Polyethylene Glycol Electrolyte Lavage Solution versus Colonic Hydrotherapy for Bowel Preparation before Colonoscopy: A Single Center, Randomized, and Controlled Study

    Directory of Open Access Journals (Sweden)

    Yan Cao

    2014-01-01

    Full Text Available This single center, randomized, and controlled study aimed to compare the effectiveness and safety of polyethylene glycol electrolyte lavage (PEG-EL solution and colonic hydrotherapy (CHT for bowel preparation before colonoscopy. A total of 196 eligible outpatients scheduled for diagnostic colonoscopy were randomly assigned to the PEG-EL (n=102 or CHT (n=94 groups. Primary outcome measures included colonic cleanliness and adverse effects. Secondary outcome measures were patient satisfaction and preference, colonoscopic findings, ileocecal arrival rate, examiner satisfaction, and cecal intubation time. The results show that PEG-EL group was associated with significantly better colonic cleanliness than CHT group, fewer adverse effects, and increased examiner satisfaction. However, the CHT group had higher patient satisfaction and higher diverticulosis detection rates. Moreover, the results showed the same ileocecal arrival rate and patient preference between the two groups (P>0.05. These findings indicate that PEG-EL is the preferred option in patients who followed the preparation instructions completely.

  6. Preparation and conductivity measurement of 7-8 mol % YSZ and 12 mol % CSZ for electrolyte SOFC

    Science.gov (United States)

    Budiana, B.; Fitriana, F.; Ayu, N.; Suasmoro, S.

    2016-08-01

    The study of 7YSZ (93% ZrO2-7%Y2O3), 8YSZ (92% ZrO2-8%Y2O3), and CSZ (88% ZrO2-12% CaO) as SOFC electrolytes have been carried out successfully. 7YSZ and 8YSZ powders were prepared by solid state reaction method of mixed Y2O3 and ZrO2 followed by calcination at 1350 °C for 1 hour, while CSZ was commercial products. Pellets of 7YSZ, 8YSZ, and CSZ were prepared by 1.2 gr, pressed at 40 MPa and sintered at 1550 °C for 4 hours. Rietveld refinement revealed that 7YSZ comprised 47.27% monoclinic, 52.65% cubic, and 0.008% Y2O3 cubic, while 8YSZ comprised 48.45% monoclinic, 49.32% cubic, 2.23% Y2O3 cubic and CSZ has 88% ZrO2 and 12% CaO. Ionic conductivity and activation energy were obtained from Cole- Cole Plot of impedance, the activation energy of 7YSZ=1.03eV, 8YSZ=0.96eV and CSZ=0.78eV.

  7. Complexation induced phase separation: preparation of composite membranes with a nanometer thin dense skin loaded with metal ions

    KAUST Repository

    Villalobos Vazquez de la Parra, Luis Francisco

    2015-04-21

    We present the development of a facile phase-inversion method for forming asymmetric membranes with a precise high metal ion loading capacity in only the dense layer. The approach combines the use of macromolecule-metal intermolecular complexes to form the dense layer of asymmetric membranes with nonsolvent-induced phase separation to form the porous support. This allows the independent optimization of both the dense layer and porous support while maintaining the simplicity of a phase-inversion process. Moreover, it facilitates control over (i) the thickness of the dense layer throughout several orders of magnitude—from less than 15 nm to more than 6 μm, (ii) the type and amount of metal ions loaded in the dense layer, (iii) the morphology of the membrane surface, and (iv) the porosity and structure of the support. This simple and scalable process provides a new platform for building multifunctional membranes with a high loading of well-dispersed metal ions in the dense layer.

  8. Complexation-induced phase separation: preparation of composite membranes with a nanometer-thin dense skin loaded with metal ions.

    Science.gov (United States)

    Villalobos, Luis Francisco; Karunakaran, Madhavan; Peinemann, Klaus-Viktor

    2015-05-13

    We present the development of a facile phase-inversion method for forming asymmetric membranes with a precise high metal ion loading capacity in only the dense layer. The approach combines the use of macromolecule-metal intermolecular complexes to form the dense layer of asymmetric membranes with nonsolvent-induced phase separation to form the porous support. This allows the independent optimization of both the dense layer and porous support while maintaining the simplicity of a phase-inversion process. Moreover, it facilitates control over (i) the thickness of the dense layer throughout several orders of magnitude from less than 15 nm to more than 6 μm, (ii) the type and amount of metal ions loaded in the dense layer, (iii) the morphology of the membrane surface, and (iv) the porosity and structure of the support. This simple and scalable process provides a new platform for building multifunctional membranes with a high loading of well-dispersed metal ions in the dense layer.

  9. Preparation of Nano-Porous Activated Carbon Aerogel Using a Single-Step Activation Method for Use as High-Power EDLC Electrode in Organic Electrolyte.

    Science.gov (United States)

    Kwon, Soon Hyung; Kim, Bum-Soo; Kim, Sang-Gil; Lee, Byung-Jun; Kim, Myung-Soo; Jung, Ji Chul

    2016-05-01

    Carbon aerogel was chemically activated with KOH using two different activation methods (conventional activation method and single-step activation method) to yield the nano-porous activated carbon aerogel. Both nano-porous activated carbon aerogels exhibited a better capacitive behavior than carbon aerogel in organic electrolyte. However, a drastic decrease in the specific capacitance with increasing current density was observed in the ACA_C (activated carbon aerogel prepared by a conventional activation method), which is a general tendency of carbon electrode for EDLC in organic electrolyte. Interestingly, the specific capacitance of ACA_S electrode (activated carbon aerogel prepared by a single-step activation method) decreased slowly with increasing current density and its CV curve maintained a rectangular shape well even at a high scan rate of 500 mV/s. The enhanced electrochemical performance of ACA_S at a high current density was attributed to its low ionic resistance caused by the well-developed pore structure with appropriate pore size for easy moving of organic electrolyte ion. Therefore, it can be concluded that single-step activation method could be one of the efficient methods for preparation of nano-porous activated carbon aerogel electrode for high-power EDLC in organic electrolyte.

  10. Preparation and characterization of lithium ion conducting polymer electrolytes based on a blend of poly(vinylidene fluoride-co-hexafluoropropylene and poly(methyl methacrylate

    Directory of Open Access Journals (Sweden)

    Merhawi Abreha Gebreyesus

    2016-07-01

    Full Text Available Ion conducting polymer electrolytes composed of poly(vinylidene fluoride-co-hexafluoropropylene (PVdF-HFP, poly(methyl methacrylate (PMMA and lithium triflate (LiTf were prepared using the solution casting method. Structural change and complex formation in the blend electrolyte systems were confirmed from the X-ray diffraction (XRD, Fourier transform infrared (FTIR spectroscopy and scanning electron microscopy (SEM studies. Thermal properties of the samples were investigated by the differential scanning calorimetry (DSC technique. The ionic conductivity of these polymer electrolytes was studied by impedance spectroscopy at various temperatures ranging from 303–393 K. The results reveal that the ionic conductivity of the polymer blend electrolytes depends on the PVdF-HFP:PMMA composition as well as the temperature. Maximum room temperature conductivity of 7.4×10−5 S cm−1 was achieved with 22.5 wt.% PMMA. The blending of PVdF-HFP with PMMA improved the thermal stability and ionic conductivity of the polymer electrolyte. Estimated transference numbers suggest the charge transport is predominantly ionic.

  11. Preparation and characterization of lithium ion conducting polymer electrolytes based on a blend of poly(vinylidene fluoride-co-hexafluoropropylene) and poly(methyl methacrylate).

    Science.gov (United States)

    Gebreyesus, Merhawi Abreha; Purushotham, Y; Kumar, J Siva

    2016-07-01

    Ion conducting polymer electrolytes composed of poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP), poly(methyl methacrylate) (PMMA) and lithium triflate (LiTf) were prepared using the solution casting method. Structural change and complex formation in the blend electrolyte systems were confirmed from the X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) studies. Thermal properties of the samples were investigated by the differential scanning calorimetry (DSC) technique. The ionic conductivity of these polymer electrolytes was studied by impedance spectroscopy at various temperatures ranging from 303-393 K. The results reveal that the ionic conductivity of the polymer blend electrolytes depends on the PVdF-HFP:PMMA composition as well as the temperature. Maximum room temperature conductivity of [Formula: see text] S cm(-1) was achieved with 22.5 wt.% PMMA. The blending of PVdF-HFP with PMMA improved the thermal stability and ionic conductivity of the polymer electrolyte. Estimated transference numbers suggest the charge transport is predominantly ionic.

  12. Preparation and study of conductivity in lithium salt complexes of mixed MEEP : PEO polymer electrolytes

    Indian Academy of Sciences (India)

    G Saibaba; D Srikanth; A Ramachandra Reddy

    2004-02-01

    Poly(ethylene oxide)–LiX complexes and poly[bis(methoxy ethoxy ethoxide) phosphazene]–LiX complexes of polymer thin films were prepared. Conductivity measurements were carried out and the values were found to lie between 10-8 and 1.7 × 10-5 (S/cm). MEEP : LiX salts showed higher conductivity than PEO–LiX salts despite lower dimensional stability. For enhancing stability and conductivity, MEEP–PEO : (LiX) systems were prepared and conductivity measurements carried out. Further the MEEP/PEO : (LiX) was doped with Al2O3 and TiO2 nanocomposite ceramic fillers and the conductivity was studied. The conductivity vs temperature plots showed the enhancement of conductivity with TiO2 added nanocomposite ceramic fillers. The enhanced conductivity is explained on the basis of the effect of local structural modification-promoting localized amorphous region-for enhancement of the Li+ ion transport.

  13. Preparation and evaluation of Ni-Zn electrode for electrolytic hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Fakeeha, A.H.; Abdel-Aleem, F.A. [King Saud Univ., Riyadh (Saudi Arabia). College of Engineering Dept. of Chemical Engineering

    2001-06-01

    An important role in enhancing the economical and technical usage of water electrolysis process is the reduction of the over potential of hydrogen evolution reaction. For this study, the authors electroplated pure Nickel and co-deposited Nickel-Zinc with different loading, to prepare two groups of electrodes. A figure illustrated the over-potential for hydrogen evolution reaction of the prepared electrodes in 1 M KOH solution at 25 Celsius as function of current density. The Nickel-Zinc electrodes gave lower over-potential, as indicated by the Tafel slopes obtained. It was also revealed that as the amount of co-deposited material increased, the over-potential was reduced, within the experimental range. The equivalent circuit for the composite electrode was developed and the roughness factor was calculated from experimental data of alternating current impedance. The explanation for the superiority of the Zinc-Nickel electrode might reside in the high value obtained for the roughness factor. 17 refs., 3 tabs., 6 figs.

  14. All-solid-state electrochemical capacitors using MnO2 electrode/SiO2-Nafion electrolyte composite prepared by the sol-gel process

    Science.gov (United States)

    Shimamoto, Kazushi; Tadanaga, Kiyoharu; Tatsumisago, Masahiro

    2014-02-01

    Electrode-electrolyte composites of MnO2 active material, acetylene black (AB), and SiO2-Nafion solid electrolyte were prepared using the sol-gel process to form good solid-solid interfaces. The composites were obtained by the addition of MnO2 and AB into a sol of hydrolyzed tetraethoxysilane with Nafion, and successive solidification of the precursor sol. Scanning electron microscope and energy dispersive X-ray spectroscopy measurements show that good solid-solid interface is formed between electrodes and solid electrolytes in the composites. All-solid-state hybrid capacitors were fabricated using the composites or the hand-grinding mixture of MnO2, AB and SiO2-Nafion powder as positive electrodes, activated carbon powder as a negative electrode, and phosphosilicate gel as a solid electrolyte. The all-solid-state hybrid capacitors using the composites exhibit larger capacitances and better rate performance than the capacitors using the electrode prepared by hand-mixing of powders. Specific discharge capacitances of the capacitor with the composite are 85 F g-1 for the one with the composite electrode and 48 F g-1 for the one with the hand-mixed electrode, at 1 mA cm-2. Moreover, the all-solid-state capacitors using the composite electrode can be operated at temperatures between -30 °C and 60 °C.

  15. Preparation and physicochemical properties of surfactant-free emulsions using electrolytic-reduction ion water containing lithium magnesium sodium silicate.

    Science.gov (United States)

    Okajima, Masahiro; Wada, Yuko; Hosoya, Takashi; Hino, Fumio; Kitahara, Yoshiyasu; Shimokawa, Ken-ichi; Ishii, Fumiyoshi

    2013-04-01

    Surfactant-free emulsions by adding jojoba oil, squalane, olive oil, or glyceryl trioctanoate (medium chain fatty acid triglycerides, MCT) to electrolytic-reduction ion water containing lithium magnesium sodium silicate (GE-100) were prepared, and their physiochemical properties (thixotropy, zeta potential, and mean particle diameter) were evaluated. At an oil concentration of 10%, the zeta potential was ‒22.3 ‒ ‒26.8 mV, showing no marked differences among the emulsions of various types of oil, but the mean particle diameters in the olive oil emulsion (327 nm) and MCT emulsion (295 nm) were smaller than those in the other oil emulsions (452-471 nm). In addition, measurement of the hysteresis loop area of each type of emulsion revealed extremely high thixotropy of the emulsion containing MCT at a low concentration and the olive emulsion. Based on these results, since surfactants and antiseptic agents markedly damage sensitive skin tissue such as that with atopic dermatitis, surfactant- and antiseptic-free emulsions are expected to be new bases for drugs for external use.

  16. La2Zr2O7 TBCs toughened by Pt particles prepared by cathode plasma electrolytic deposition

    Science.gov (United States)

    Deng, Shun-jie; Wang, Peng; He, Ye-dong; Zhang, Jin

    2016-06-01

    La2Zr2O7 thermal barrier coatings (TBCs) with dispersed Pt particles were prepared by cathode plasma electrolytic deposition (CPED) with ceramic balls added to the cathode region. Compared with the conventional CPED, when ceramic balls are used in the cathode region, the plasma discharge ignition current density decreases approximately 62-fold and the stable plasma discharges occur at the whole cathode surface. Such TBCs with a thickness of 100 μm exhibit a crack-free surface and are composed of pyrochlore-structured La2Zr2O7. Cyclic oxidation, scratching, and thermal insulation capability tests show that such TBCs not only exhibit high resistance to oxidation and spallation but also provide good thermal insulation. These beneficial effects are attributed to the excellent properties of TBCs, such as good thermal insulation because of low thermal conductivity, high-temperature oxidation resistance because of low-oxygen diffusion rate, and good mechanical properties because of the toughening effect of Pt particles.

  17. Preparation and characterization of Na3BO3–Na2SO4 glass electrolytes with Na+ ion conductivity prepared by a mechanical milling technique

    Directory of Open Access Journals (Sweden)

    Kenji Suzuki

    2016-03-01

    Full Text Available The (100 − xNa3BO3·xNa2SO4 (0 ≤ x (mol% ≤ 50 glasses were prepared by mechanical milling. Halo patterns were observed in the compositions 0 ≤ x ≤ 50 by XRD measurements. The Raman spectra indicated that all the glasses were composed of BO33− anions, SO42− anions and Na+ cations. The (100 − xNa3BO3·xNa2SO4 glasses showed good deformation properties and a dense pellet was prepared by cold-press. The conductivities of the glasses increased with increasing Na2SO4 content, and the 50Na3BO3·50Na2SO4 glass showed the highest conductivity of 5.9 × 10−8 S cm−1 at 25 °C.

  18. Preparation of catalyst for a polymer electrolyte fuel cell using a novel spherical carbon support

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, Mika; Okubo, Atsuhiko; Kobayashi, Yoshio [Department of Biomolecular Functional Engineering, Faculty of Engineering, Ibaraki University, 4-12-1, Nakanarusawa, Hitachi, Ibaraki 316-8511 (Japan); Yamamoto, Shun [Material and Biological Sciences, Graduate School of Science and Engineering, Faculty of Engineering, Ibaraki University, 4-12-1, Nakanarusawa, Hitachi, Ibaraki 316-8511 (Japan); Kikuchi, Mayuko; Nishitani-Gamo, Mikka [Department of Applied Chemistry, Faculty of Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585 (Japan); Uno, Katsuhiro [Department of Media and Telecommunications Engineering, Faculty of Engineering, Ibaraki University, 4-12-1, Nakanarusawa, Hitachi, Ibaraki 316-8511 (Japan); Ando, Toshihiro [National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2010-09-15

    In this study, the support Pt catalyst was supported by a novel spherical carbon using a convenient technique. Two different preparation methods utilizing a nanocolloidal solution method without heat treatment were developed (methods 1 and 2). The scanning electron microscope (SEM) and transmission electron microscope (TEM) observations showed that the Pt nanoparticles (particle size) were supported, with higher dispersion being achieved with method 2 than method 1. The peak of the Pt metal was confirmed from the X-ray diffraction (XRD) measurement. Based on the inductively coupled plasma mass spectrometry (ICP-MS) measurements, Pt loading was 19.5 wt.% in method 1 and approximately 50 wt.% in method 2. The Pt specific surface area of the Pt/novel spherical carbon catalyst calculated from the cyclic voltammetry (CV) measurement result was larger than that of the commercially available Pt/Ketjen catalyst. These results indicated that the Pt nanoparticles were supported in high dispersion without heat treatment using novel spherical carbon as a carbon support. (author)

  19. Preparation and characterization of poly(lithium acrylate-arcylonitrile)/LiClO4-LiNO3-LiBr solid polymer electrolytes

    Institute of Scientific and Technical Information of China (English)

    PAN Chun-yue; YUAN Yun-lan; CHEN Zhen-hua; XU Xian-hua; ZHANG Jian

    2005-01-01

    Through orthogonal experiment, a new type of LiClO4-LiNO3-LiBr eutectic salt with optimum mole ratio of n(LiClO4):n(LiNO3):n(LiBr)=1.6:3.8:1.0 was prepared. The poly(lithium acrylate-acrylonitrile)/LiClO4-LiNO3-LiBr solid polymer electrolytes were prepared with poly(lithium acrylate-acrylonitrile) and LiClO4-LiNO3-LiBr eutectic salts. The effect of LiClO4-LiNO3-LiBr eutectic salts content on the conductivity of solid polymer electrolytes was studied by alternating current impedance method, and the structures of eutectic salts and solid polymer electrolytes were characterized by differential thermal analysis, infrared spectroscopy and X-ray diffractometry. The results show that the room temperature conductivity of LiClO4-LiNO3-LiBr eutectic salts reaches 3.11×10-4 S·cm-1. The poly(lithium acrylate-acrylonitrile)/LiClO4-LiNO3-LiBr solid polymer electrolytes possess the highest room temperature conductivity at 70% LiClO4-LiNO3-LiBr eutectic salts content, and exhibit lower glass transition temperature of 75 ℃ compared with that of poly(lithium acrylate-acrylonitrile) of 105 ℃. A complex may be formed in the solid polymer electrolytes from the differential thermal analysis and infrared spectroscopy analysis. X-ray diffraction results show that the poly(lithium acrylate-acrylonitrile) can suppress the crystallization of eutectic salts in this system.

  20. Preparation and properties of PEO/LiClO4/KH560-SiO2 composite polymer electrolyte by sol-gel composite-in-situ method

    Institute of Scientific and Technical Information of China (English)

    PAN Chun-yue; GAO Jin-huan; ZHANG Qian; FENG Qing; CHAO meng

    2008-01-01

    Composite polymer electrolytes based on polyethylene oxide (PEO) were prepared by using LiClO4 as doping salt and silane-modified SiO2 as filler. SiO2 was formed in-situ in (PEO)8LiClO4 matrix by the hydrolysis and condensation reaction of Si(OC4H9)4. The crystallinity, morphology and ionic conductivity of composite polymer electrolyte films were examined by differential scanning calorimetry, scanning electron microscopy, atom force microscopy and alternating current impedance spectroscopy, respectively. Compared with the crystallinity of the unmodified SiO2 as inert filler, that of composite polymer electrolytes is decreased. The results show that silane-modified SiO2 particles are uniformly dispersed in (PEO)8LiClO4 composite polymer electrolyte film and the addition of silane-modified SiO2 increases the ionic conductivity of the (PEO)8LiClO4 more noticeably. When the mass fraction of SiO2 is about 10%, the conductivity of (PEO)8LiClO4-modified SiO2 attains a maximum value of 4.8×10-5S·cm-1.

  1. Preparation of anode-electrolyte structures using graphite, sodium bicarbonate or citric acid as pore forming agents for application in solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Paz Fiuza, Raigenis da; Silva, Marcos Aurelio da; Guedes, Bruna C.; Pontes, Luiz A.; Boaventura, Jaime Soares [UFBA, Salvador, Bahia (Brazil). Energy and Materials Science Group

    2010-07-01

    Cermets based on Ni supported on YSZ or GDC were prepared for use as anode in direct reform SOFCs. NaHCO3 (Na-Ni-YSZ and Na-Ni-GDC) or citric acid (Ac-Ni-YSZ and Ac-Ni-GDC) were used as pore forming agents (PFAs). The SOFC anode was also prepared using graphite (G-Ni-YSZ and G-Ni-GDC) as PFA for the purposes of comparison. The testing unitary SOFC, planar type, was made by pressing the anode-electrolyte assembly, followed by sintering at 1500 C. After this, LSM (lanthanum and strontium manganite) paint was used for the cathode deposition. The powdered cermets were evaluated in ethanol steam reforming at 650 C. The ethanol conversion was 84% and 32% for cermets Na-Ni-YSZ and G-Ni-YSZ, respectively and the selectivity to H{sub 2} was 32 and 20% for the two cermets, respectively. The Na-Ni-YSZ cermet was ten times more resistant to carbon deposition than the G-Ni-YSZ cermet. SEM micrographs of the anode-electrolyte assembly showed that the use of NaHCO{sub 3} as PFA created a well formed interface between layers with homogeneously distributed pores. In contrast, graphite as PFA formed a loose interface between anode and electrolyte. The performance of the unitary SOFC was evaluated using ethanol, hydrogen or methane as fuel. The cell operated well using any of these fuels; however, they exhibited different electrochemical behavior. (orig.)

  2. Preparation and characterization of a micro-porous polymer electrolyte with cross-linking network structure for dye-sensitized solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Wei, T.C.; Wan, C.C.; Wang, Y.Y. [Department of Chemical Engineering, National Tsing-Hua University, 101, Section 2, Kuang Fu Road, Hsin-Chu 300 (China)

    2007-12-14

    A PVdF-HFP/PEG/PEGDMA cross-linking film has been prepared as the electrolyte for dye-sensitized solar cell (DSSC). The film can be made porous by controlling the evaporation behavior of solvents. Room temperature ionic conductivity of the micro-porous film exceeds 1 mS/cm. In addition, we also evaluated the significance of cell gap in DSSC by analyzing the impedance spectroscopy of the cell with polymer electrolyte. Finally, by decreasing the film thickness, the DSSC equipped with 11 {mu}m, micro-porous and cross-linked film showed a conversion efficiency over 4% and 5% under 1 and 0.16 Sun, respectively. (author)

  3. Preparation of hydroxide ion conductive KOH–layered double hydroxide electrolytes for an all-solid-state iron–air secondary battery

    Directory of Open Access Journals (Sweden)

    Taku Tsuneishi

    2014-06-01

    Full Text Available Anion conductive solid electrolytes based on Mg–Al layered double hydroxide (LDH were prepared for application in an all-solid-state Fe–air battery. The ionic conductivity and the conducting ion species were evaluated from impedance and electromotive force measurements. The ion conductivity of LDH was markedly enhanced upon addition of KOH. The electromotive force in a water vapor concentration cell was similar to that of an anion-conducting polymer membrane. The KOH–LDH obtained was used as a hydroxide ion conductive electrolyte for all-solid-state Fe–air batteries. The cell performance of the Fe–air batteries was examined using a mixture of KOH–LDH and iron-oxide-supported carbon as the negative electrode.

  4. Preparation and characterization of PVC/PMMA blend polymer electrolytes complexed with LiN(C2F5SO22

    Directory of Open Access Journals (Sweden)

    R. Nimma Elizabeth

    2004-03-01

    Full Text Available Thin films of polymer blend electrolytes comprising Poly(vinyl chloride (PVC and Poly(methyl methacrylate(PMMA and plasticized with a combination of ethylene carbonate (EC and propylene carbonate (PC for different lithium imide salt, LiN(C2F5SO32 , concentrations were prepared using the solution casting technique. The films were subjected to a. c. impedance measurements as a function of temperature ranging from -30 °C to 70 °C. The variation of ionic conductivity as a function of temperature and PVC content in the blend was analysed. The role of PMMA in the phenomena occurring at the interface between the plasticized polymer electrolyte and lithium electrode was also studied. The cast films were also subjected to TG/DTA and FT-IR studies which are discussed.

  5. Preparation of cubic Li{sub 7}La{sub 3}Zr{sub 2}O{sub 12} solid electrolyte using a nano-sized core–shell structured precursor

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yanhua; Cai, Jin [State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Chen, Fei, E-mail: chenfei027@gmail.com [State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Massachusetts Institute of Technology, 77 Massachusetts Avenue, W20-021 Cambridge, MA 02139-4307 (United States); Tu, Rong; Shen, Qiang; Zhang, Xulong [State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Zhang, Lianmeng [State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Massachusetts Institute of Technology, 77 Massachusetts Avenue, W20-021 Cambridge, MA 02139-4307 (United States)

    2015-09-25

    Highlights: • A core–shell nano-sized precursor was synthesized by a two-step precipitation. • Cubic LLZO dense body was obtained at low temperatures by the novel precursor. • The cubic LLZO sintered body showed an extremely high Li ionic conductivity. - Abstract: Nano-sized Al-doped Li{sub 7}La{sub 3}Zr{sub 2}O{sub 12} (LLZO) precursor is successfully synthesized by a novel two-step precipitation method. Microstructure and thermal behavior of the prepared LLZO precursor powders and properties of the sintered LLZO pellets are comprehensively investigated. Results show that the obtained precursor powders have a special core–shell structure that a coating of Li{sub 2}C{sub 2}O{sub 4} covers on the surface of the lanthanum and zirconium co-precipitate products. Pure cubic LLZO powders can be obtained at a low calcination temperature of 900 °C. Sample sintered by field assisted sintering technology at 1000 °C has a high relative density of 96.5% with a total ionic conductivity of as high as 3.32 × 10{sup −4} S cm{sup −1} (corresponding to the activation energy of 0.32 eV) at room temperature. The reported method provides a simple and low-temperature synthesis of high quality LLZO solid electrolytes.

  6. Stresses and Temperature Stability of Dense Wavelength Division Multiplexing Filters Prepared by Reactive Ion-Assisted E-Gun Evaporation

    Science.gov (United States)

    Wei, Chao-Tsang; Shieh, Han-Ping D.

    2005-10-01

    In this paper, we report the in situ measurement of the temperature stability of narrow-band-pass filters on different types of substrate, for dense wavelength division multiplexing (DWDM) filters in optical-fiber transmission systems. The DWDM filters were designed as all-dielectric Fabry-Perot filters and fabricated by reactive ion-assisted deposition. Ta2O5 and SiO2 were used as high- and low-refractive-index layers, respectively, for constructing the DWDM filters. The accuracy and stability of the coating process were evaluated for fabricating the DWDM filters for the temperature stability of the center wavelength. The center wavelength shift was determined to be greatly dependent on the coefficient of thermal expansion of the substrate on which the filter is deposited.

  7. Highly dispersed TaOx nanoparticles prepared by electrodeposition as oxygen reduction electrocatalysts for polymer electrolyte fuel cells

    KAUST Repository

    Seo, Jeongsuk

    2013-06-06

    Based on the chemical stability of group IV and V elements in acidic solutions, TaOx nanoparticles prepared by electrodeposition in an ethanol-based Ta plating bath at room temperature were investigated as novel nonplatinum electrocatalysts for the oxygen reduction reaction (ORR) in polymer electrolyte fuel cells (PEFCs). Electrodeposition conditions of Ta complexes and subsequent various heat treatments for the deposited TaOx were examined for the best performance of the ORR. TaOx particles on carbon black (CB), electrodeposited at a constant potential of -0.5 V Ag/AgCl for 10 s and then heat-treated by pure H2 flow at 523 K for 1 h, showed excellent catalytic activity with an onset potential of 0.93 VRHE (for 2 μA cm-2) for the ORR. Surface characterizations of the catalysts were performed by scanning transmission electron microscopy (STEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDS). The loading amounts of the electrodeposited material on the CB were determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). All the physical results suggested that high dispersion of TaOx particles on the CB surface with 2-3 nm size was critical and key for high activity. The chemical identity and modified surface structure for the deposited TaOx catalysts before and after H 2 heat treatment were analyzed by X-ray photoelectron spectroscopy (XPS). The formation of more exposed active sites on the electrode surface and enhanced electroconductivity of the tantalum oxide promoted from the H 2 treatment greatly improved the ORR performance of the electrodeposited TaOx nanoparticles on CB. Finally, the highly retained ORR activity after an accelerated durability test in an acidic solution confirmed and proved the chemical stability of the oxide nanoparticles. The high utilization of the electrodeposited TaOx nanoparticles uniformly dispersed on CB for the ORR was comparable to that of commercial Pt/CB catalysts

  8. Lubiprostone plus PEG electrolytes versus placebo plus PEG electrolytes for outpatient colonoscopy preparation: a randomized, double-blind placebo-controlled trial.

    Science.gov (United States)

    Sofi, Aijaz A; Nawras, Ali T; Pai, Chetan; Samuels, Qiana; Silverman, Ann L

    2015-01-01

    Bowel preparation using large volume of polyethylene glycol (PEG) solutions is often poorly tolerated. Therefore, there are ongoing efforts to develop an alternative bowel cleansing regimen that should be equally effective and better tolerated. The aim of this study was to assess the efficacy of lubiprostone (versus placebo) plus PEG as a bowel cleansing preparation for colonoscopy. Our study was a randomized, double-blind placebo-controlled design. Patients scheduled for screening colonoscopy were randomized 1:1 to lubiprostone (group 1) or placebo (group 2) plus 1 gallon of PEG. The primary endpoints were patient's tolerability and endoscopist's evaluation of the preparation quality. The secondary endpoint was to determine any reduction in the amount of PEG consumed in the lubiprostone group compared with the placebo group. One hundred twenty-three patients completed the study and were included in the analysis. There was no difference in overall cleanliness. The volume of PEG was similar in both the groups. The volume of PEG approached significance as a predictor of improved score for both the groups (P = 0.054). Lubiprostone plus PEG was similar to placebo plus PEG in colon cleansing and volume of PEG consumed. The volume of PEG consumed showed a trend toward improving the quality of the colon cleansing.

  9. Preparation and characterization of PEG–Mg(CH3COO)2–CeO2 composite polymer electrolytes for battery application

    Indian Academy of Sciences (India)

    Anji Reddy Polu; Ranveer Kumar

    2014-04-01

    Composite polymer electrolytes based on poly(ethylene glycol) (PEG), magnesium acetate [Mg(CH3COO)2], and wt% of cerium oxide (CeO2) ceramic fillers (where = 0, 5, 10, 15 and 20, respectively) have been prepared using solution casting technique. X-ray diffraction patterns of PEG–Mg(CH3COO)2 with CeO2 ceramic filler indicated the decrease in the degree of crystallinity with increasing concentration of the filler. DSC measurements of PEG–Mg(CH3COO)2-CeO2 composite polymer electrolyte system showed that the melting temperature is shifted towards the lower temperature with increase of the filler concentration. The conductivity results indicate that the incorporation of ceramic filler up to a certain concentration (i.e. 15 wt%) increases the ionic conductivity and upon further addition the conductivity decreases. The transference number data indicated the dominance of ion-type charge transport in these specimens. Using this (PEG–Mg(CH3COO)2-CeO2) (85-15-15) electrolyte, solid-state electrochemical cell was fabricated and their discharge profiles were studied under a constant load of 100 k.

  10. Preparation and characterization of Ce0.8La0.2-xYxO1.9 as electrolyte for solid oxide fuel cells

    Institute of Scientific and Technical Information of China (English)

    田长安; 季必发; 谢劲松; 鲍巍涛; 刘可; 程继海; 尹奇异

    2014-01-01

    In this study, ultrafine Ce0.8La0.2–xYxO1.9 (for x=0, 0.05, 0.10, 0.15, 0.20) powders were successfully prepared by the sol-gel method. The samples were characterized by fourier transform infrared (FTIR), thermogravimetric and differential scanning calo-rimetry (TG-DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), AC impedance and thermal expansion measure-ments. Experimental results indicated that highly phase-pure cubic fluorite electrolyte Ce0.8La0.2–xYxO1.9 powders were obtained after calcining at 600 °C. The as-synthesized powders exhibited high sintering activity, the Ce0.8La0.2–xYxO1.9 series electrolytes which have higher relative densities over 96%could be obtained after sintered at 1400 °C for 4 h. Ce0.8La0.15Y0.05O1.9 electrolyte sintered at 1400 °C for 4 h exhibited higher oxide ionic conductivity (σ800 ºC=0.057 S/cm), lower electrical activation energy (Ea=0.87 eV) and moder-ate thermal expansion coefficient (TEC=15.5×10−6 K−1, temperature range 25–800 °C).

  11. Dense Breasts

    Science.gov (United States)

    ... also appear white on mammography, they can be hidden by or within dense breast tissue. Other imaging ... understanding of the possible charges you will incur. Web page review process: This Web page is reviewed ...

  12. Morphology, luminescence, and electrical resistance response to H 2 and CO gas exposure of porous InP membranes prepared by electrochemistry in a neutral electrolyte

    Science.gov (United States)

    Volciuc, O.; Monaico, E.; Enachi, M.; Ursaki, V. V.; Pavlidis, D.; Popa, V.; Tiginyanu, I. M.

    2010-11-01

    Porous InP membranes have been prepared by anodization of InP wafers with electron concentration of 1 × 10 17 cm -3 and 1 × 10 18 cm -3 in a neutral NaCl electrolyte. The internal surfaces of pores in some membranes were modified by electrochemical deposition of gold in a pulsed voltage regime. Photoluminescence and photosensitivity measurements indicate efficient light trapping and porous surface passivation. The photoluminescence and electrical resistivity of the membranes are sensitive to the adsorption of H 2 and CO gas molecules. These properties are also influenced by the deposition of Au nanoparticles inside the pores.

  13. Morphology, luminescence, and electrical resistance response to H{sub 2} and CO gas exposure of porous InP membranes prepared by electrochemistry in a neutral electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Volciuc, O.; Monaico, E.; Enachi, M. [National Center for Materials Study and Testing, Technical University of Moldova, Bd. Stefan cel Mare 168, Chisinau 2004 (Moldova, Republic of); Ursaki, V.V., E-mail: ursaki@yahoo.com [Institute of Applied Physics, Academy of Sciences of Moldova, Academy str. 5, Chisinau 2028 (Moldova, Republic of); Pavlidis, D. [Fachgebiet fuer Hoechstfrequenzelektronik, Technische Universitaet Darmstadt, Merckstrasse 25, Darmstadt 64283 (Germany); Popa, V. [National Center for Materials Study and Testing, Technical University of Moldova, Bd. Stefan cel Mare 168, Chisinau 2004 (Moldova, Republic of); Fachgebiet fuer Hoechstfrequenzelektronik, Technische Universitaet Darmstadt, Merckstrasse 25, Darmstadt 64283 (Germany); Tiginyanu, I.M. [National Center for Materials Study and Testing, Technical University of Moldova, Bd. Stefan cel Mare 168, Chisinau 2004 (Moldova, Republic of); Institute of Electronic Engineering and Nanotechnologies, Academy of Sciences of Moldova, Academy str. 3/3, Chisinau 2028 (Moldova, Republic of)

    2010-11-15

    Porous InP membranes have been prepared by anodization of InP wafers with electron concentration of 1 x 10{sup 17} cm{sup -3} and 1 x 10{sup 18} cm{sup -3} in a neutral NaCl electrolyte. The internal surfaces of pores in some membranes were modified by electrochemical deposition of gold in a pulsed voltage regime. Photoluminescence and photosensitivity measurements indicate efficient light trapping and porous surface passivation. The photoluminescence and electrical resistivity of the membranes are sensitive to the adsorption of H{sub 2} and CO gas molecules. These properties are also influenced by the deposition of Au nanoparticles inside the pores.

  14. Preparation, characterization and luminescent properties of dense nano-silica hybrids loaded with 1,8-naphthalic anhydride.

    Science.gov (United States)

    Wang, Jinpeng; Sun, Jihong; Li, Yuzhen; Wang, Feng

    2014-03-01

    Novel luminescent dense nano-silica hybrid materials (DNSS) modified with different amounts of (3-aminopropyl)triethoxysilane (APTES) and 1,8-naphthalic anhydride (NA) were successfully synthesized via two steps combined with post-grafting methods. Powder X-ray diffraction (XRD), N2-sorption analysis, Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), photoluminescence (PL) spectroscopy and elemental analysis, as well as time-resolved decays were employed to characterize the resultant hybrid materials. The results revealed that luminescent organic molecules had been successfully loaded onto the amine-modified surface of nano-silica spheres. In addition, their fluorescence intensity and characteristic peak of emission spectra changed with increasing amount of APTES and NA additive. In particular, the characteristic peak showed a red shift from 390 to 450 nm, however, this was inconsistent with results calculated on the basis of the elemental analysis data, most probably because of the dispersion behaviors of NA molecules from the aggregating to the monolayer state. These observations demonstrated the existence of a quantum confinement effectiveness of NA-DNSS samples, and therefore a possible mechanism was put forward.

  15. Fabrication of supported Ca-doped lanthanum niobate electrolyte layer and NiO containing anode functional layer by electrophoretic deposition

    DEFF Research Database (Denmark)

    Bozza, Francesco; Bonanos, Nikolaos

    2012-01-01

    The technique of electrophoretic deposition (EPD) has been applied for the preparation of a dense calcium-doped lanthanum niobate electrolyte film. La0.995Ca0.005NbO4 (LCN) powder was suspended in a solution of acetylacetone, iodine and water. The effects of suspension composition and deposition...

  16. Impact de la preparation des anodes crues et des conditions de cuisson sur la fissuration dans des anodes denses

    Science.gov (United States)

    Amrani, Salah

    La fabrication de l'aluminium est realisee dans une cellule d'electrolyse, et cette operation utilise des anodes en carbone. L'evaluation de la qualite de ces anodes reste indispensable avant leur utilisation. La presence des fissures dans les anodes provoque une perturbation du procede l'electrolyse et une diminution de sa performance. Ce projet a ete entrepris pour determiner l'impact des differents parametres de procedes de fabrication des anodes sur la fissuration des anodes denses. Ces parametres incluent ceux de la fabrication des anodes crues, des proprietes des matieres premieres et de la cuisson. Une recherche bibliographique a ete effectuee sur tous les aspects de la fissuration des anodes en carbone pour compiler les travaux anterieurs. Une methodologie detaillee a ete mise au point pour faciliter le deroulement des travaux et atteindre les objectifs vises. La majorite de ce document est reservee pour la discussion des resultats obtenus au laboratoire de l'UQAC et au niveau industriel. Concernant les etudes realisees a l'UQAC, une partie des travaux experimentaux est reservee a la recherche des differents mecanismes de fissuration dans les anodes denses utilisees dans l'industrie d'aluminium. L'approche etait d'abord basee sur la caracterisation qualitative du mecanisme de la fissuration en surface et en profondeur. Puis, une caracterisation quantitative a ete realisee pour la determination de la distribution de la largeur de la fissure sur toute sa longueur, ainsi que le pourcentage de sa surface par rapport a la surface totale de l'echantillon. Cette etude a ete realisee par le biais de la technique d'analyse d'image utilisee pour caracteriser la fissuration d'un echantillon d'anode cuite. L'analyse surfacique et en profondeur de cet echantillon a permis de voir clairement la formation des fissures sur une grande partie de la surface analysee. L'autre partie des travaux est basee sur la caracterisation des defauts dans des echantillons d'anodes crues

  17. Electrolyte composition dependence of the morphological and nanostructural features of porous silicon prepared by electrochemical anodic etching

    Science.gov (United States)

    Kim, Hyo-Han; Son, Jong-Ick; Yun, Han-Sol; Cho, Nam-Hee

    2014-11-01

    Porous silicon layers were formed by electrochemical anodic etching of p-type Si wafers. The electrostatic condition at the interface between the Si wafers and electrolytes was affected sensitively by the addition of isopropyl alcohol (IPA) in the etchant. As the IPA ratio was varied in the range of 0 to 75%, the ideality factor in the ln I-V relationships and the viscosity of the electrolytes changed from 27.2 to 16.0, and from 1.0 to 3.3 cp, respectively. The etched surface exhibited three different morphologies, such as `turtle-back'-, `column'-, and `mountain'-like structures depending on the electrolyte composition. The etched layers contained Si nanocrystallites, 5.5 to 2.6 nm in size, which exhibited photoluminescence features in the wavelength range, 733 to 624 nm. The variation of the band gap was determined by size of the nanocrystallites, whereas the nanostructural and morphological features were dependent on the IPA ratios of the etchants.

  18. Preparation of Microporous Polypropylene/Titanium Dioxide Composite Membranes with Enhanced Electrolyte Uptake Capability via Melt Extruding and Stretching

    Directory of Open Access Journals (Sweden)

    Shan Wang

    2017-03-01

    Full Text Available In this work, a blending strategy based on compounding the hydrophilic titanium dioxide (TiO2 particles with the host polypropylene (PP pellets, followed by the common membrane manufacture process of melt extruding/annealing/stretching, was used to improve the polarity and thus electrolyte uptake capability of the PP-based microporous membranes. The influence of the TiO2 particles on the crystallinity and crystalline orientation of the PP matrix was studied using differential scanning calorimetry (DSC, X-ray diffraction (XRD, and infrared dichroic methods. The results showed that the TiO2 incorporation has little influence on the oriented lamellar structure of the PP-based composite films. Investigations of the deformation behavior indicated that both the lamellar separation and interfacial debonding occurred when the PP/TiO2 composite films were subjected to uniaxial tensile stress. The scanning electron microscopy (SEM observations verified that two forms of micropores were generated in the stretched PP/TiO2 composite membranes. Compared to the virgin PP membrane, the PP/TiO2 composite membranes especially at high TiO2 loadings showed significant improvements in terms of water vapor permeability, polarity, and electrolyte uptake capability. The electrolyte uptake of the PP/TiO2 composite membrane with 40 wt % TiO2 was 104%, which had almost doubled compared with that of the virgin PP membrane.

  19. Characterization of Al{sub 2}O{sub 3} ceramic coatings on 6063 aluminum alloy prepared in borate electrolytes by micro-arc oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Li, H.X. [MOE Key Laboratory of Mechanical Manufacture and Automation, Zhejiang University of Technology, No. 6, Zhaohui District, Hangzhou 310014 (China); Rudnev, V.S. [Institute of Chemistry FEB RAS, Pr. 100 let Vladivostok, Vladivostok 690022 (Russian Federation); Zheng, X.H. [MOE Key Laboratory of Mechanical Manufacture and Automation, Zhejiang University of Technology, No. 6, Zhaohui District, Hangzhou 310014 (China); Yarovaya, T.P. [Institute of Chemistry FEB RAS, Pr. 100 let Vladivostok, Vladivostok 690022 (Russian Federation); Song, R.G. [MOE Key Laboratory of Mechanical Manufacture and Automation, Zhejiang University of Technology, No. 6, Zhaohui District, Hangzhou 310014 (China)], E-mail: songrg@zjut.edu.cn

    2008-08-25

    Al{sub 2}O{sub 3} ceramic coatings were directly prepared on 6063 aluminum alloy in borate electrolytes by micro-arc oxidation technique. The microstructure, phase composition, elemental distribution, and micro-hardness of Al{sub 2}O{sub 3} ceramic coatings were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and micro-hardness test. The fabricated samples were almost composed of {alpha}-Al{sub 2}O{sub 3} and {gamma}-Al{sub 2}O{sub 3}, also there existed pores and cracks on the surface of the coatings. Micro-hardness test shows that the prepared coatings are of high hardness, which can satisfy the requirements for the mechanical application.

  20. Metal Oxide Assisted Preparation of Core-Shell Beads with Dense Metal-Organic Framework Coatings for the Enhanced Extraction of Organic Pollutants.

    Science.gov (United States)

    Del Rio, Mateo; Palomino Cabello, Carlos; Gonzalez, Veronica; Maya, Fernando; Parra, Jose B; Cerdà, Victor; Turnes Palomino, Gemma

    2016-08-08

    Dense and homogeneous metal-organic framework (MOF) coatings on functional bead surfaces are easily prepared by using intermediate sacrificial metal oxide coatings containing the metal precursor of the MOF. Polystyrene (PS) beads are coated with a ZnO layer to give ZnO@PS core-shell beads. The ZnO@PS beads are reactive in the presence of 2-methylimidazole to transform part of the ZnO coating into a porous zeolitic imidazolate framework-8 (ZIF-8) external shell positioned above the internal ZnO precursor shell. The obtained ZIF-8@ZnO@PS beads can be easily packed in column format for flow-through applications, such as the solid-phase extraction of trace priority-listed environmental pollutants. The prepared material shows an excellent permeance to flow when packed as a column to give high enrichment factors, facile regeneration, and excellent reusability for the extraction of the pollutant bisphenol A. It also shows an outstanding performance for the simultaneous enrichment of mixtures of endocrine disrupting chemicals (bisphenol A, 4-tert-octylphenol and 4-n-nonylphenol), facilitating their analysis when present at very low levels (coatings.

  1. LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

    Energy Technology Data Exchange (ETDEWEB)

    Harlan U. Anderson

    2000-03-31

    This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and Testing of Planar Single Cells. During this time period substantial progress has been made in developing low temperature deposition techniques to produce dense, nanocrystalline yttrium-stabilized zirconia films on both dense oxide and polymer substrates. Progress has been made in the preparation and characterization of thin electrolytes and porous LSM substrates. Both of these tasks are essentially on or ahead of schedule. In our proposal, we suggested that the ZrO{sub 2}/Sc system needed to be considered as a candidate as a thin electrolyte. This was because microcrystalline ZrO{sub 2}/Sc has a significantly higher ionic conductivity than YSZ, particularly at the lower temperatures. As a result, some 0.5 micron thick film of ZrO{sub 2}/16% Sc on an alumina substrate (grain size 20nm) was prepared and the electrical conductivity measured as a function of temperature and oxygen activity. The Sc doped ZrO{sub 2} certainly has a higher conductivity that either 20nm or 2400nm YSZ, however, electronic conductivity dominates the conductivity for oxygen activities below 10{sup -15}. Whereas for YSZ, electronic conductivity is not a problem until the oxygen activity decreases below 10{sup -25}. These initial results show that the ionic conductivity of 20nm YSZ and 20nm ZrO{sub 2}/16% Sc are essentially the same and the enhanced conductivity which is observed for Sc doping in microcrystalline specimens is not observed for the same composition when it is nanocrystalline. In addition they show that the electronic conductivity of Sc doped ZrO{sub 2} is at least two orders of magnitude higher than that observed for YSZ. The conclusion one reaches is that for 0.5 to 1 micron thick nanocrystalline films, Sc doping of ZrO{sub 2} has no benefits compared to YSZ. As a result, electrolyte films of ZrO{sub 2}/Sc should not be considered as candidates

  2. Dense and high-stability Ti2AlN MAX phase coatings prepared by the combined cathodic arc/sputter technique

    Science.gov (United States)

    Wang, Zhenyu; Liu, Jingzhou; Wang, Li; Li, Xiaowei; Ke, Peiling; Wang, Aiying

    2017-02-01

    Ti2AlN belongs to a family of ternary nano-laminate alloys known as the MAX phases, which exhibit a unique combination of metallic and ceramic properties. In the present work, the dense and high-stability Ti2AlN coating has been successfully prepared through the combined cathodic arc/sputter deposition, followed by heat post-treatment. It was found that the as-deposited Ti-Al-N coating behaved a multilayer structure, where (Ti, N)-rich layer and Al-rich layer grew alternately, with a mixed phase constitution of TiN and TiAlx. After annealing at 800 °C under vacuum condition for 1.5 h, although the multilayer structure still was found, part of multilayer interfaces became indistinct and disappeared. In particular, the thickness of the Al-rich layer decreased in contrast to that of as-deposited coating due to the inner diffusion of the Al element. Moreover, the Ti2AlN MAX phase emerged as the major phase in the annealed coatings and its formation mechanism was also discussed in this study. The vacuum thermal analysis indicated that the formed Ti2AlN MAX phase exhibited a high-stability, which was mainly benefited from the large thickness and the dense structure. This advanced technique based on the combined cathodic arc/sputter method could be extended to deposit other MAX phase coatings with tailored high performance like good thermal stability, high corrosion and oxidation resistance etc. for the next protective coating materials.

  3. Densely crosslinked polycarbosiloxanes .1. Synthesis

    NARCIS (Netherlands)

    Flipsen, T.A C; Derks, R.; van der Vegt, H.A.; Pennings, A.J; Hadziioannou, G

    1997-01-01

    Novel densely crosslinked polycarbosiloxanes were obtained by using functional branched prepolymers. Two types of soluble prepolymers were prepared from di- and trifunctional alkoxysilane monomers via cohydrolysis/condensation and for both final crosslinking occurred via hydrosilylation. The prepoly

  4. Preparation of Ceramic Tiles with Electrolytic Manganese and Waste Glass Admicture%利用电解锰渣-废玻璃制备陶瓷砖

    Institute of Scientific and Technical Information of China (English)

    冉岚; 刘少友; 杨红芸; 张扬

    2015-01-01

    In order to solve the pollution of electrolytic manganese residue, the environment and improve the utilization of manganese slag, the preparation of ceramic tiles was studied by using electrolytic manganese and waste glass as the main raw material. The basic formulas were obtained in terms of the CaO-Al2O3-SiO2 termary system phase diagram, then they were optimized through a lot of experiments and the text of crystallization. The results indicated that the calcining temperature was 950℃electrolysis manganese when adding 32%electrolytic manganese and 10 g waste glass, the main crystals composition were quartz, cristobalite, mullite and anorthite, the shrinkage is 0.27%, it complied with the standard of GB/T 4100-2006 ceramic tiles.%为了解决电解锰渣对环境的污染,提高锰渣的利用率,研究了以电解锰渣-废玻璃为主要原料制备陶瓷砖。首先利用CaO-Al2O3-SiO2三相图获得初始配方,然后进行了大量的实验,并对产品的晶相进行分析,确定陶瓷砖的最优配方。结果证明,锰渣的添加量为32%,废玻璃含量为25%,煅烧温度为950℃,煅烧时间为30 min时,陶瓷坯的主晶相为石英、钙长石、莫来石和方石英,收缩率为0.27%,符合GB/T 4100-2006陶瓷砖的标准。

  5. Evaluating focused ion beam and ultramicrotome sample preparation for analytical microscopies of the cathode layer of a polymer electrolyte membrane fuel cell

    Science.gov (United States)

    de A. Melo, Lis G.; Hitchcock, Adam P.; Berejnov, Viatcheslav; Susac, Darija; Stumper, Juergen; Botton, Gianluigi A.

    2016-04-01

    Optimizing the structure of the porous electrodes of polymer electrolyte membrane fuel cells (PEM-FC) can improve device power and durability. Analytical microscopy techniques are important tools for measuring the electrode structure, thereby providing guidance for structural optimization. Transmission Electron Microscopy (TEM), with either Energy Dispersive X-Ray (EDX) or Electron Energy Loss Spectroscopy (EELS) analysis, and Scanning Transmission X-Ray Microscopy (STXM) are complementary methods which, together, provide a powerful approach for PEM-FC electrode analysis. Both TEM and STXM require thin (50-200 nm) samples, which can be prepared either by Focused Ion Beam (FIB) milling or by embedding and ultramicrotomy. Here we compare TEM and STXM spectromicroscopy analysis of FIB and ultramicrotomy sample preparations of the same PEM-FC sample, with focus on how sample preparation affects the derived chemical composition and spatial distributions of carbon support and ionomer. The FIB lamella method, while avoiding pore-filling by embedding media, had significant problems. In particular, in the FIB sample the carbon support was extensively amorphized and the ionomer component suffered mass loss and structural damage. Although each sample preparation technique has a role to play in PEM-FC optimization studies, it is important to be aware of the limitations of each method.

  6. Efficacy of Indigenous Herbal Preparation on Altered Milk pH, Somatic Cell Count and Electrolyte Profile in Subclinical Mastitis in Cows

    Directory of Open Access Journals (Sweden)

    A.Y. Kolte

    Full Text Available Comparative efficacy of three different locally prepared indigenous herbal paste were evaluated in subclinical 24 mastitic cows with reference to restoring altered milk pH, somatic cell count and milk electrolyte profile. The study revealed that all the treatment were found effective in restoring the altered milk constituents in subclinical mastitis with increased in the milk production. T3 (oots of Withania somnifera (Ashwagandha, Asparagus reacemosus (Shatavari, Curcuma-amada (Ambe Haldi and fresh leaves of Ocimum sanctum (Tulsi in equal quantities was found more effective than T5 ( T3 and T4 in combination in equal quantities and T4 (fresh roots of Glycerrhiza glabra (Jeshathamadh, Nardostachys jatamansi (Jatamansi, leaves of Riccinus communis (Yerand, bark of Ficus racemosa (Umber and rhizome of Curcuma longa (Haldi in equal quantities [Veterinary World 2008; 1(8.000: 239-240

  7. Electrical Properties of Ba3Ca1.18Nb1.82O9-  Proton-Conducting Electrolyte Prepared by a Combustion Method

    KAUST Repository

    Bi, Lei

    2013-10-07

    Ba3Ca1.18Nb1.82O9-δ (BCN18), regarded as a promising proton-conducting electrolyte material for solid oxide fuel cells, is usually synthesized by a solid-state reaction because of the limited choice of Nb precursors. This study presents a wet chemical route for preparing BCN18 powders that were then sintered into pellets. Electrochemical impedance spectroscopy studies indicated that BCN18 pellets show proton conductivity, since their total conductivity in wet air was significantly larger than that in dry air. However, a detailed analysis showed that only the BCN18 bulk behaves as a proton conductor, while its grain boundary conductivity did not increase in wet air.

  8. Preparation and Characterization of Amorphous Layer on Aluminum Alloy Formed by Plasma Electrolytic Deposition (PED)

    Institute of Scientific and Technical Information of China (English)

    GUANYong-jun; XIAYuan

    2004-01-01

    In this investigation, protective layers were formed on aluminum substrate by Plasma Electrolytic Deposition (PED) using sodium silicate solution. The relation between the thickness of the layer and process time were studied. XRD, SEM, EDS were used to study the layer's structure, composition and micrograph. The results show that the deposited layers are amorphous and contain mainly oxygen, silicon, and aluminum. The possible formation mechanism of amorphous[Al-Si-O] layer was proposed: During discharge periods, Al2O3 phase of the passive film and SiO32- near the substrate surface are sintered into xSiO2(1-x)Al2O3 and then transformed into amorphous [Al-Si-O] phase.

  9. POLYMER ELECTROLYTE MEMBRANE FUEL CELLS

    DEFF Research Database (Denmark)

    2001-01-01

    A method for preparing polybenzimidazole or polybenzimidazole blend membranes and fabricating gas diffusion electrodes and membrane-electrode assemblies is provided for a high temperature polymer electrolyte membrane fuel cell. Blend polymer electrolyte membranes based on PBI and various thermopl......A method for preparing polybenzimidazole or polybenzimidazole blend membranes and fabricating gas diffusion electrodes and membrane-electrode assemblies is provided for a high temperature polymer electrolyte membrane fuel cell. Blend polymer electrolyte membranes based on PBI and various...... thermoplastic polymers for high temperature polymer electrolyte fuel cells have also been developed. Miscible blends are used for solution casting of polymer membranes (solid electrolytes). High conductivity and enhanced mechanical strength were obtained for the blend polymer solid electrolytes...... electrolyte membrane by hot-press. The fuel cell can operate at temperatures up to at least 200 °C with hydrogen-rich fuel containing high ratios of carbon monoxide such as 3 vol% carbon monoxide or more, compared to the carbon monoxide tolerance of 10-20 ppm level for Nafion$m(3)-based polymer electrolyte...

  10. Polymer Electrolytes for Lithium/Sulfur Batteries

    Directory of Open Access Journals (Sweden)

    The Nam Long Doan

    2012-08-01

    Full Text Available This review evaluates the characteristics and advantages of employing polymer electrolytes in lithium/sulfur (Li/S batteries. The main highlights of this study constitute detailed information on the advanced developments for solid polymer electrolytes and gel polymer electrolytes, used in the lithium/sulfur battery. This includes an in-depth analysis conducted on the preparation and electrochemical characteristics of the Li/S batteries based on these polymer electrolytes.

  11. Efficiently dense hierarchical graphene based aerogel electrode for supercapacitors

    Science.gov (United States)

    Wang, Xin; Lu, Chengxing; Peng, Huifen; Zhang, Xin; Wang, Zhenkun; Wang, Gongkai

    2016-08-01

    Boosting gravimetric and volumetric capacitances simultaneously at a high rate is still a discrepancy in development of graphene based supercapacitors. We report the preparation of dense hierarchical graphene/activated carbon composite aerogels via a reduction induced self-assembly process coupled with a drying post treatment. The compact and porous structures of composite aerogels could be maintained. The drying post treatment has significant effects on increasing the packing density of aerogels. The introduced activated carbons play the key roles of spacers and bridges, mitigating the restacking of adjacent graphene nanosheets and connecting lateral and vertical graphene nanosheets, respectively. The optimized aerogel with a packing density of 0.67 g cm-3 could deliver maximum gravimetric and volumetric capacitances of 128.2 F g-1 and 85.9 F cm-3, respectively, at a current density of 1 A g-1 in aqueous electrolyte, showing no apparent degradation to the specific capacitance at a current density of 10 A g-1 after 20000 cycles. The corresponding gravimetric and volumetric capacitances of 116.6 F g-1 and 78.1 cm-3 with an acceptable cyclic stability are also achieved in ionic liquid electrolyte. The results show a feasible strategy of designing dense hierarchical graphene based aerogels for supercapacitors.

  12. Preparation of carbon alloy catalysts for polymer electrolyte fuel cells from nitrogen-containing rigid-rod polymers

    Energy Technology Data Exchange (ETDEWEB)

    Chokai, Masayuki [Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152-8552 (Japan); Integrative Technology Research Institute, Teijin Ltd., 4-3-2, Asahigaoka, Hino, Tokyo 191-8512 (Japan); Taniguchi, Masataka; Shinoda, Tsuyoshi; Nabae, Yuta; Kuroki, Shigeki; Hayakawa, Teruaki; Kakimoto, Masa-aki [Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152-8552 (Japan); Moriya, Shogo; Matsubayashi, Katsuyuki [Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152-8552 (Japan); Business Development Division, Nisshinbo Holdings, Inc., 1-2-3, Onodai, Midori-ku, Chiba 267-0056 (Japan); Ozaki, Jun-ichi [Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152-8552 (Japan); Department of Nanomaterial Systems, Graduate School of Engineering, Gunma University, 1-5-1, Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Miyata, Seizo [Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152-8552 (Japan); New Energy and Industrial Technology Development Organization, 1310 Omiya-cho, Saiwai-ku, Kawasaki, Kanagawa 212-8554 (Japan)

    2010-09-15

    Carbon alloy catalysts (CAC), non-precious metal catalysts for the oxygen reduction reaction (ORR), were prepared from various kinds of nitrogen-containing rigid-rod aromatic polymers, polyimides, polyamides and azoles, by carbonization at 900 C under nitrogen flow. The catalytic activity for ORR was evaluated by the onset potential, which was taken at a current density of -2 {mu}A cm{sup -2}. Carbonized polymers having high nitrogen content showed higher onset potential. In particular, CACs derived from azole (Az5) had an onset potential of 0.8 V, despite being was prepared without any metals. (author)

  13. Integrin-mediated osteoblastic adhesion on a porous manganese-incorporated TiO2 coating prepared by plasma electrolytic oxidation.

    Science.gov (United States)

    Zhang, Zhenxiang; Gu, Beibei; Zhu, Wei; Zhu, Lixian

    2013-09-01

    This study was conducted to evaluate the bioactivity of manganese-incorporated TiO2 (Mn-TiO2) coating prepared on titanium (Ti) plate by plasma electrolytic oxidation (PEO) technique in Ca-, P- and Mn-containing electrolytes. The surface topography, phase and element compositions of the coatings were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectrometry (EDS), respectively. The adhesion of osteoblast-like MG63 cells onto Ti, TiO2 and Mn-TiO2 surfaces was evaluated, and the signal transduction pathway involved was confirmed by the sequential expression of the genes for integrins β1, β3, α1 and α3, focal adhesion kinase (FAK), and the extracellular regulated kinases (ERKs), including ERK1 and ERK2. The results obtained indicated that Mn was successfully incorporated into the porous nanostructured TiO2 coating, and did not alter the surface topography or the phase composition of the coating. The adhesion of the MG63 cells onto the Mn-incorporated TiO2 coating was significantly enhanced compared with that on the Mn-free TiO2 coating and the pure Ti plates. In addition, the enhanced cell adhesion on the Mn-TiO2 coatings may have been mediated by the binding of the integrin subunits, β1 and α1, and the subsequent signal transduction pathway, involving FAK and ERK2. The study indicated that the novel Mn-TiO2 coating has potential for orthopedic implant applications, and that further investigations are required.

  14. Preparation of thick-film electrode-solid electrolyte composites on Li7La3Zr2O12 and their electrochemical properties

    Science.gov (United States)

    Kato, Takeshia; Iwasaki, Shinya; Ishii, Yosuke; Motoyama, Munekazu; West, William C.; Yamamoto, Yuta; Iriyama, Yasutoshi

    2016-01-01

    We prepared up to 20 μm-thick LiNi1/3Co1/3Mn1/3O2 (NMC)-Li+ conductive glass-ceramic solid electrolyte (LATP: σLi+ ˜ 10-3 S cm-2 at 298 K) composite cathode films on Li7La3Zr2O12 (LLZ) substrates by aerosol deposition (AD) and investigated their electrochemical properties as all-solid-state batteries. The resultant NMC/LATP interface in the composite film had a thin mutual diffusion layer (˜5 nm) and a film had a porosity of ca. 0.15% in volume. The composite films were well adhered to the LLZ substrates even though the films were prepared at room temperature. All-solid-state batteries, consisting of Li/LLZ/NMC-LATP composite film (20 μm), repeated charge-discharge reactions for 90 cycles at 100 °C at a 1/10 C rate (capacity retention: 99.97%/cycle). Rate capability of this battery was improved by modifying both the LATP and electron conductive source amount in the composite film, and a battery with 16 μm-thick composite electrode delivered 60 mAh g-1 at 1 mA cm-2.

  15. DMFC Performance of Polymer Electrolyte Membranes Prepared from a Graft-Copolymer Consisting of a Polysulfone Main Chain and Styrene Sulfonic Acid Side Chains

    Directory of Open Access Journals (Sweden)

    Nobutaka Endo

    2016-08-01

    Full Text Available Polymer electrolyte membranes (PEMs for direct methanol fuel cell (DMFC applications were prepared from a graft-copolymer (PSF-g-PSSA consisting of a polysulfone (PSF main chain and poly(styrene sulfonic acid (PSSA side chains with various average distances between side chains (Lav and side chain lengths (Lsc. The polymers were synthesized by grafting ethyl p-styrenesulfonate (EtSS on macro-initiators of chloromethylated polysulfone with different contents of chloromethyl (CM groups, and by changing EtSS content in the copolymers by using atom transfer radical polymerization (ATRP. The DMFC performance tests using membrane electrode assemblis (MEAs with the three types of the PEMs revealed that: a PSF-g-PSSA PEM (SF-6 prepared from a graft copolymer with short average distances between side chains (Lav and medium Lsc had higher DMFC performance than PEMs with long Lav and long Lsc or with short Lav and short Lsc. SF-6 had about two times higher PDmax (68.4 mW/cm2 than Nafion® 112 at 30 wt % of methanol concentration. Furthermore, it had 58.2 mW/cm2 of PDmax at 50 wt % of methanol concentration because of it has the highest proton selectivity during DMFC operation of all the PSF-g-PSSA PEMs and Nafion® 112.

  16. Ion conducting solid polymer electrolytes based on polypentafluorostyrene-b-polyether-b-polypentafluorostyrene prepared by atom transfer radical polymerization

    DEFF Research Database (Denmark)

    Jankova, Katja; Jannasch, P.; Hvilsted, Søren

    2004-01-01

    Novel triblock copolymers based on central poly( ethylene glycol) ( PEG) or poly( ethylene glycol-co-propylene glycol) (PEGPG) blocks with poly( pentafluorostyrene) (PFS) outer blocks were prepared by Atom Transfer Radical Polymerization (ATRP) with polydispersities on the order of 1.2 - 1...

  17. Electrolytic preparation of iron from aqueous solution using solar energy%利用太阳能在水溶液中电解制铁

    Institute of Scientific and Technical Information of China (English)

    董洪波; 侯明山; 刘超; 刘润藻; 李士琦

    2012-01-01

    以太阳能电池板光伏转换所得电能为电源,采用正交试验对电解氯化亚铁溶液制取纯铁的工艺进行优化,得到最佳电解参数为:FeCl2·4H2O375g/L,pH=2.0,电流密度3 A/dm2,温度50℃.在最佳工艺下,电流效率和电沉积速率分别达到88.9%和0.45 g/h,所得铁表面光滑,呈银白色金属光泽.利用太阳能电解制铁对以后的清洁能源制铁具有一定的借鉴作用.%With the electric energy obtained by photovoltaic technology using solar-cell panels as the power supply, the process parameters for preparation of pure iron from aqueous ferrous chloride solution by electrolysis were optimized by orthogonal test as follows: FeCl2-4H2O 375 g/L, pH 2.0, current density 3 A/dm2, and temperature 50 °C. Under the optimal parameters, the current efficiency and deposition rate are up to 88.95% and 0.45 g/L respectively and the surface of the obtained iron is smooth with silvery white color and metallic luster. The electrolytic preparation of iron using solar energy gives reference to the future preparation of iron with clean energy.

  18. The Role of Sub- and Supercritical CO2 as "Processing Solvent" for the Recycling and Sample Preparation of Lithium Ion Battery Electrolytes.

    Science.gov (United States)

    Nowak, Sascha; Winter, Martin

    2017-03-06

    Quantitative electrolyte extraction from lithium ion batteries (LIB) is of great interest for recycling processes. Following the generally valid EU legal guidelines for the recycling of batteries, 50 wt % of a LIB cell has to be recovered, which cannot be achieved without the electrolyte; hence, the electrolyte represents a target component for the recycling of LIBs. Additionally, fluoride or fluorinated compounds, as inevitably present in LIB electrolytes, can hamper or even damage recycling processes in industry and have to be removed from the solid LIB parts, as well. Finally, extraction is a necessary tool for LIB electrolyte aging analysis as well as for post-mortem investigations in general, because a qualitative overview can already be achieved after a few minutes of extraction for well-aged, apparently "dry" LIB cells, where the electrolyte is deeply penetrated or even gellified in the solid battery materials.

  19. The Role of Sub- and Supercritical CO2 as “Processing Solvent” for the Recycling and Sample Preparation of Lithium Ion Battery Electrolytes

    Directory of Open Access Journals (Sweden)

    Sascha Nowak

    2017-03-01

    Full Text Available Quantitative electrolyte extraction from lithium ion batteries (LIB is of great interest for recycling processes. Following the generally valid EU legal guidelines for the recycling of batteries, 50 wt % of a LIB cell has to be recovered, which cannot be achieved without the electrolyte; hence, the electrolyte represents a target component for the recycling of LIBs. Additionally, fluoride or fluorinated compounds, as inevitably present in LIB electrolytes, can hamper or even damage recycling processes in industry and have to be removed from the solid LIB parts, as well. Finally, extraction is a necessary tool for LIB electrolyte aging analysis as well as for post-mortem investigations in general, because a qualitative overview can already be achieved after a few minutes of extraction for well-aged, apparently “dry” LIB cells, where the electrolyte is deeply penetrated or even gellified in the solid battery materials.

  20. Conductivity study of dense BaCex Zr(0.9-x)Y0.1O(3 − δ) prepared by solid state reactive sintering at 1500 deg. C

    DEFF Research Database (Denmark)

    Ricote, Sandrine; Bonanos, Nikolaos; Manerbino, A.

    2012-01-01

    A cost and time effective process was used to prepare the solid solutions BaCexZr(0.9−x)Y0.1O(3−δ) (0 ≤ x ≤ 0.4). 98% dense samples were obtained by solid state reactive sintering at 1500 °C for 4 h, with the addition of 1 wt% of NiO to the quantity of synthesized/sintered compound. Scanning...

  1. Effect of the catalytic ink preparation method on the performance of high temperature polymer electrolyte membrane fuel cells

    Science.gov (United States)

    Lobato, J.; Rodrigo, M. A.; Linares, J. J.; Scott, K.

    Two methods of preparation of the membrane-electrode-assemblies based on polybenzimidazole membranes have been studied for high temperatures PEMFCs. One is called the "colloidal method" (using acetone as solvent), and the other is the "solution method" (using dimethylacetamide as solvent). Physical property studies (SEM micrographs and pore size distribution) and electrochemical analyses in half-cell (Electrochemical Impedance Spectroscopy, Polarization Curves for Oxygen Reduction and Cyclic Voltammetry) were carried out to characterise the structural and electrochemical behaviour of both methods. Finally, a cell performance investigation, using electrodes prepared by both methods was carried out at three different temperatures (125, 150, and 175 °C), in a single PEMFC setup. A better behaviour was obtained for the "solution method" at the two highest temperatures at intermediate current densities, whereas at 125 °C the best results were obtained with the "colloidal method" in all the current densities ranges. A discussion of the behaviours observed with the different characterisation techniques is made.

  2. Effect of the catalytic ink preparation method on the performance of high temperature polymer electrolyte membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Lobato, J.; Rodrigo, M.A.; Linares, J.J. [Chemical Engineering Department, University of Castilla-La Mancha, Campus Universitario s/n, 13004 Ciudad Real (Spain); Scott, K. [School of Chemical Engineering and Advanced Materials, University of Newcastle upon Tyne, Merz Court NE1 7RU (United Kingdom)

    2006-06-19

    Two methods of preparation of the membrane-electrode-assemblies based on polybenzimidazole membranes have been studied for high temperatures PEMFCs. One is called the 'colloidal method' (using acetone as solvent), and the other is the 'solution method' (using dimethylacetamide as solvent). Physical property studies (SEM micrographs and pore size distribution) and electrochemical analyses in half-cell (Electrochemical Impedance Spectroscopy, Polarization Curves for Oxygen Reduction and Cyclic Voltammetry) were carried out to characterise the structural and electrochemical behaviour of both methods. Finally, a cell performance investigation, using electrodes prepared by both methods was carried out at three different temperatures (125, 150, and 175{sup o}C), in a single PEMFC setup. A better behaviour was obtained for the 'solution method' at the two highest temperatures at intermediate current densities, whereas at 125{sup o}C the best results were obtained with the 'colloidal method' in all the current densities ranges. A discussion of the behaviours observed with the different characterisation techniques is made. (author)

  3. Preparation and properties of functionalized multiwalled carbon nanotubes/polypropylene nanocomposite bipolar plates for polymer electrolyte membrane fuel cells

    Science.gov (United States)

    Liao, Shu-Hang; Weng, Cheng-Chih; Yen, Chuan-Yu; Hsiao, Min-Chien; Ma, Chen-Chi M.; Tsai, Ming-Chi; Su, Ay; Yen, Ming-Yu; Lin, Yu-Feng; Liu, Po-Lan

    Multiwalled carbon nanotubes (MWCNTs) are covalently modified with different molecular weights 400 and 2000 poly(oxyalkylene)-amine bearing the diglycidyl ether of bisphenol A (DGEBA) epoxy (POA400-DGEBA and POA2000-DGEBA) oligomers. The oxidized MWCNTs (MWCNTs-COOH) are converted to the acid chloride-functionalized MWCNTs, followed by the reaction with POA-DGEBAs to prepare the MWCNTs/POA400-DGEBA and MWCNTs/POA2000-DGEBA. FTIR, thermogravimetric analysis (TGA) and high resolution X-ray photoelectron spectra (XPS) reveal that the POA-DGEBAs are covalently attached to the surface of MWCNTs. The morphology of MWCNTs/POA-DGEBA is observed by TEM. The POA400-DGEBA coated on the MWCNTs is thicker and more uniform. However, the coating of POA2000-DGEBA on the MWCNTs shows a worm-like bulk substance and the MWCNT surface is bare. In addition, the flexural strength and the bulk electrical conductivity of the MWCNTs/polypropylene nanocomposite bipolar plates are measured 59% and 505% higher than those of the original composite bipolar plates by adding 8 phr of MWCNTs/POA400-DGEBA. The maximum current density and power density of the single cell test for the nanocomposite bipolar plate with 4 phr MWCNTs/POA400-DGEBA are 1.32 A cm -2 and 0.533 W cm -2, respectively. The overall performance confirms the functionalized MWCNTs/polypropylene nanocomposite bipolar plates prepared in this study are suitable for PEMFC application.

  4. Preparation and properties of functionalized multiwalled carbon nanotubes/polypropylene nanocomposite bipolar plates for polymer electrolyte membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Shu-Hang; Weng, Cheng-Chih; Yen, Chuan-Yu.; Hsiao, Min-Chien; Ma, Chen-Chi M.; Yen, Ming-Yu.; Liu, Po-Lan [Department of Chemical Engineering, National Tsing Hua University, Hsin-Chu 30043 (China); Tsai, Ming-Chi [Department of Engineering and System Science, National Tsing Hua University, Hsin-Chu 30043 (China); Su, Ay [Fuel Cell Center, Yuan Ze University, Tao-Yuan 32003 (China); Lin, Yu-Feng [Plastics Industry Development Center, Tai-Chung 40768 (China)

    2010-01-01

    Multiwalled carbon nanotubes (MWCNTs) are covalently modified with different molecular weights 400 and 2000 poly(oxyalkylene)-amine bearing the diglycidyl ether of bisphenol A (DGEBA) epoxy (POA400-DGEBA and POA2000-DGEBA) oligomers. The oxidized MWCNTs (MWCNTs-COOH) are converted to the acid chloride-functionalized MWCNTs, followed by the reaction with POA-DGEBAs to prepare the MWCNTs/POA400-DGEBA and MWCNTs/POA2000-DGEBA. FTIR, thermogravimetric analysis (TGA) and high resolution X-ray photoelectron spectra (XPS) reveal that the POA-DGEBAs are covalently attached to the surface of MWCNTs. The morphology of MWCNTs/POA-DGEBA is observed by TEM. The POA400-DGEBA coated on the MWCNTs is thicker and more uniform. However, the coating of POA2000-DGEBA on the MWCNTs shows a worm-like bulk substance and the MWCNT surface is bare. In addition, the flexural strength and the bulk electrical conductivity of the MWCNTs/polypropylene nanocomposite bipolar plates are measured 59% and 505% higher than those of the original composite bipolar plates by adding 8 phr of MWCNTs/POA400-DGEBA. The maximum current density and power density of the single cell test for the nanocomposite bipolar plate with 4 phr MWCNTs/POA400-DGEBA are 1.32 A cm{sup -2} and 0.533 W cm{sup -2}, respectively. The overall performance confirms the functionalized MWCNTs/polypropylene nanocomposite bipolar plates prepared in this study are suitable for PEMFC application. (author)

  5. POLYMER ELECTROLYTE MEMBRANE FUEL CELLS

    DEFF Research Database (Denmark)

    2001-01-01

    A method for preparing polybenzimidazole or polybenzimidazole blend membranes and fabricating gas diffusion electrodes and membrane-electrode assemblies is provided for a high temperature polymer electrolyte membrane fuel cell. Blend polymer electrolyte membranes based on PBI and various...... thermoplastic polymers for high temperature polymer electrolyte fuel cells have also been developed. Miscible blends are used for solution casting of polymer membranes (solid electrolytes). High conductivity and enhanced mechanical strength were obtained for the blend polymer solid electrolytes....... With the thermally resistant polymer, e.g., polybenzimidazole or a mixture of polybenzimidazole and other thermoplastics as binder, the carbon-supported noble metal catalyst is tape-cast onto a hydrophobic supporting substrate. When doped with an acid mixture, electrodes are assembled with an acid doped solid...

  6. Preparation of electrolyte thin film on NiO-YSZ porous substrate for solid oxide fuel cells by electrophoretic deposition (I)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.W.; Lee, B.H.; Son, Y.B.; Song, H.S. [Korea Institute of Science and Technology, Seoul (Korea)

    1999-05-01

    Yttria-stabilized zirconia(YSZ) thin films for an anode support type solid oxide fuel cell(SOFC) was prepared by electrophoretic deposition(EPD). Kinetic model and properties of electrolyte film obtained by EPD on porous NiO-YSZ substrate were investigated. In the constant current mode, the deposited weight increased with time and the curve was well-fitted by Dihyperbola type function. In constant voltage mode, the deposited weight saturated with time, and the curve was fitted by the modified Zhangs' equation. There was little difference in the weight and microstructure of films between constant current and constant voltage conditions in short time(under 30 s), but the surface of deposited film at constant current condition was more smooth than that at constant voltage condition. Although zirconia films, obtained under either conditions at low electric field for long time processing, contained defects such as sagging and crack, sagging of film at constant voltage condition was more sever than for constant current condition. YSZ thin film with uniform thickness of less than 10 {mu}m by EPD was formed at constant current, 0.035 mA/cm{sup 2} for 10 s. 19 refs., 12 figs.

  7. Coatable Li4 SnS4 Solid Electrolytes Prepared from Aqueous Solutions for All-Solid-State Lithium-Ion Batteries.

    Science.gov (United States)

    Choi, Young Eun; Park, Kern Ho; Kim, Dong Hyeon; Oh, Dae Yang; Kwak, Hi Ram; Lee, Young-Gi; Jung, Yoon Seok

    2017-06-22

    Bulk-type all-solid-state lithium-ion batteries (ASLBs) for large-scale energy-storage applications have emerged as a promising alternative to conventional lithium-ion batteries (LIBs) owing to their superior safety. However, the electrochemical performance of bulk-type ASLBs is critically limited by the low ionic conductivity of solid electrolytes (SEs) and poor ionic contact between the active materials and SEs. Herein, highly conductive (0.14 mS cm(-1) ) and dry-air-stable SEs (Li4 SnS4 ) are reported, which are prepared using a scalable aqueous-solution process. An active material (LiCoO2 ) coated by solidified Li4 SnS4 from aqueous solutions results in a significant improvement in the electrochemical performance of ASLBs. Side-effects of the exposure of LiCoO2 to aqueous solutions are minimized by using predissolved Li4 SnS4 solution. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

    Energy Technology Data Exchange (ETDEWEB)

    Harlan U. Anderson; Wayne Huebner; Igor Kosacki

    2001-09-30

    This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and testing of Planar Single Cells. In this portion of study we have focused on producing YSZ films on porous LSM substrates. When using the polymer precursor there are a number of obstacles to overcome in order to form dense electrolyte layers on porous substrates (cathode or anode). Probably the most difficult problems are: (1) Extreme penetration of the polymer into the substrate must be prevented. (2) Shrinkage cracking must be avoided. (3) Film thickness in the 1 to 5{micro}m range must be achieved. We have demonstrated that cracking due to shrinkage involved during the elimination of solvents and organic matter and densification of the remaining oxide is not a problem as long as the resulting oxide film is < {approx} 0.15 {micro}m in thickness. We have also shown that we can make thicker films by making multiple depositions if the substrate is smooth (roughness {le} 0.1 {micro}m) and contains no surface pores > 0.2 {micro}m. The penetration of the polymer into the porous substrate can be minimized by increasing the viscosity of the polymer and reducing the largest pore at the surface of the substrate to {le} 0.2 {micro}m. We have shown that this can be done, but we have also shown that it is difficult to make dense films that are defect free with areas > 1 cm{sup 2}. This is because of the roughness of the substrate and the difficulty in making a substrate which does not have surface voids > 0.2 {micro}m. Thus the process works well for dense, smooth substrates for films < 1 {micro}m thick, but is difficult to apply to rough, porous surfaces and to make film thickness > 1 {micro}m. As a result of these problems, we have been addressing the issue of how to make dense films in the thickness range of 1 to 5 {micro}m on sintered porous substrates without introducing cracks and holes due to shrinkage and surface voids? These

  9. Nitrate conversion and supercritical fluid extraction of UO{sub 2}-CeO{sub 2} solid solution prepared by an electrolytic reduction-coprecipitation method

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, L.Y. [Tsinghua Univ., Beijing (China). Inst. of Nuclear and New Energy Technology; China Institute of Atomic Energy, Beijing (China); Duan, W.H.; Wen, M.F.; Xu, J.M.; Zhu, Y.J. [Tsinghua Univ., Beijing (China). Inst. of Nuclear and New Energy Technology

    2014-04-01

    A low-waste technology for the reprocessing of spent nuclear fuel (SNF) has been developed recently, which involves the conversion of actinide and lanthanide oxides with liquid N{sub 2}O{sub 4} into their nitrates followed by supercritical fluid extraction of the nitrates. The possibility of the reprocessing of SNF from high-temperature gas-cooled reactors (HTGRs) with nitrate conversion and supercritical fluid extraction is a current area of research in China. Here, a UO{sub 2}-CeO{sub 2} solid solution was prepared as a surrogate for a UO{sub 2}-PuO{sub 2} solid solution, and the recovery of U and Ce from the UO{sub 2}-CeO{sub 2} solid solution with liquid N{sub 2}O{sub 4} and supercritical CO{sub 2} containing tri-n-butyl phosphate (TBP) was investigated. The UO{sub 2}-CeO{sub 2} solid solution prepared by electrolytic reduction-coprecipitation method had square plate microstructures. The solid solution after heat treatment was completely converted into nitrates with liquid N{sub 2}O{sub 4}. The XRD pattern of the nitrates was similar to that of UO{sub 2}(NO{sub 3}){sub 2} . 3H{sub 2}O. After 120 min of online extraction at 25 MPa and 50 , 99.98% of the U and 98.74% of the Ce were recovered from the nitrates with supercritical CO{sub 2} containing TBP. The results suggest a promising potential technology for the reprocessing of SNF from HTGRs. (orig.)

  10. Effect of poly(ethylene oxide) on ionic conductivity and electrochemical properties of poly(vinylidenefluoride) based polymer gel electrolytes prepared by electrospinning for lithium ion batteries

    Science.gov (United States)

    Prasanth, Raghavan; Shubha, Nageswaran; Hng, Huey Hoon; Srinivasan, Madhavi

    2014-01-01

    Effect of poly(ethylene oxide) on the electrochemical properties of polymer electrolyte based on electrospun, non-woven membrane of PVdF is demonstrated. Electrospinning process parameters are controlled to get a fibrous membrane consisting of bead-free, uniformly dispersed thin fibers with diameter in the range of 1.5-1.9 μm. The membrane with good mechanical strength and porosity exhibits high uptake when activated with the liquid electrolyte of lithium salt in a mixture of organic solvents. The polymer gel electrolyte shows ionic conductivity of 4.9 × 10-3 S cm-1 at room temperature. Electrochemical performance of the polymer gel electrolyte is evaluated in Li/polymer electrolyte/LiFePO4 coin cell. Good performance with low capacity fading on charge-discharge cycling is demonstrated.

  11. Multi-layered proton-conducting electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tae H.; Dorris, Stephen E.; Balachandran, Uthamalingam

    2017-06-27

    The present invention provides a multilayer anode/electrolyte assembly comprising a porous anode substrate and a layered solid electrolyte in contact therewith. The layered solid electrolyte includes a first dense layer of yttrium-doped barium zirconate (BZY), optionally including another metal besides Y, Ba, and Zr (e.g., a lanthanide metal such as Pr) on one surface thereof, a second dense layer of yttrium-doped barium cerate (BCY), and an interfacial layer between and contacting the BZY and BCY layers. The interfacial layer comprises a solid solution of the BZY and BCY electrolytes. The porous anode substrate comprises at least one porous ceramic material that is stable to carbon dioxide and water (e.g., porous BZY), as well as an electrically conductive metal and/or metal oxide (e.g., Ni, NiO, and the like).

  12. Oxygen reduction reaction catalyzed by platinum nanonetwork prepared by template free one step synthesis for polymer electrolyte membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Narayanamoorthy, B. [Department of Chemistry, Faculty of Science, Sri Chandrasekharendra Saraswathi Viswa Mahavidyalaya (SCSVMV University), Enathur, Kanchipuram 631 561 (India); Kumar, B.V.V.S. Pavan; Eswaramoorthy, M. [Nanomaterials and Catalysis Lab, Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore 560 064 (India); Balaji, S., E-mail: prof.balaji13@gmail.com [Department of Chemistry, Faculty of Science, Sri Chandrasekharendra Saraswathi Viswa Mahavidyalaya (SCSVMV University), Enathur, Kanchipuram 631 561 (India)

    2014-07-01

    Highlights: • Supportless Pt nanonetwork (Pt NN) synthesized by novel template free one step method as per our earlier reported procedure. • Electrocatalytic activity of Pt NN studied taking oxygen reduction reaction in acid medium. • Kinetic and thermodynamic parameters were deduced under hydrodynamic conditions. • ORR mechanistic pathway was proposed based on kinetic rate constants. • ADT analysis found enhanced stability (5000 cycles) for Pt NN than Pt NN/VC and reported Pt/C. - Abstract: The reduction reaction of molecular oxygen (ORR) was investigated using supportless Pt nanonetwork (Pt NN) electrocatalyst in sulfuric acid medium. Pt NN was prepared by template free borohydride reduction. The transmission electron microscope images revealed a network like nano-architecture having an average cluster size of 30 nm. The electrochemical characterization of supportless and Vulcan carbon supported Pt NN (Pt NN/VC) was carried out using rotating disc and ring disc electrodes at various temperatures. Kinetic and thermodynamic parameters were estimated under hydrodynamic conditions and compared with Pt NN/VC and reported Pt/C catalysts. The accelerated durability test revealed that supportless Pt NN is quite stable for 5000 potential cycles with 22% reduction in electrochemical surface area (ECSA). While the initial limiting current density has in fact increased by 11.6%, whereas Pt NN/VC suffered nearly 55% loss in ECSA and 13% loss in limiting current density confirming an enhanced stability of supportless Pt NN morphology for ORR compared to conventional Pt/C ORR catalysts in acid medium.

  13. Electrocatalytic activity and electrochemical hydrogen storage of Ni-La alloy prepared by electrodeposition from aqueous electrolyte

    Institute of Scientific and Technical Information of China (English)

    陈卫祥; 成旦红; 刘淑兰; 郭鹤桐

    2002-01-01

    Ni-La alloy coating was prepared by electrodeposition.The effect of cathodic current density on the La content of the alloy coatings was discussed.It is found that the content of La in the alloy increases with increasing the cathodic current density.The microstructures and codeposition mechanism of Ni-La alloy coatings were investigated by means of X-ray diffraction (XRD) and cyclic voltammetry (CV).The results demonstrate that the Ni-La alloy is FCC and codeposited by the induced mechanism.The hydrogen evolution reaction (HER) on the electrodeposited Ni-La alloy electrodes in alkaline solution was evaluated by Tafel polarization curves.It is found that La-Ni alloy coating exhibites much higher exchange current density for HER than pure Ni electrode,and that the exchange current density increases with increasing the La content of alloys.The good electrocatalytic activity for HER of this Ni-La alloy is attributed to the synergism of the electronic structure of La and Ni.The electrodeposited La-Ni alloys have a certain electrochemical hydrogen storage capacity of 34~143 mAh/g,which increases with increasing the La content of alloys.

  14. Preparation and properties of carbon nanotube/polypropylene nanocomposite bipolar plates for polymer electrolyte membrane fuel cells

    Science.gov (United States)

    Liao, Shu-Hang; Yen, Chuan-Yu; Weng, Cheng-Chih; Lin, Yu-Feng; Ma, Chen-Chi M.; Yang, Ching-Hung; Tsai, Ming-Chi; Yen, Ming-Yu; Hsiao, Min-Chien; Lee, Shuo-Jen; Xie, Xiao-Feng; Hsiao, Yi-Hsiu

    This study aims at the fabrication of lightweight and high performance nanocomposite bipolar plates for the application in polymer electrode membrane fuel cells (PEMFCs). The thin nanocomposite bipolar plates (the thickness polypropylene (PP) with different crystallinities including high crystallinity PP (HC-PP), medium crystallinity PP (MC-PP), low crystallinity PP (LC-PP) were prepared to investigate the influence of crystallinity on the dispersion of MWCNTs in PP matrix. The optimum composition of original composite bipolar plates was determined at 80 wt.% graphite content and 20 wt.% PP content based on the measurements of electrical and mechanical properties with various graphite contents. Results also indicate that MWCNTs was dispersed better in LC-PP than other PP owing to enough dispersed regions in nanocomposite bipolar plates. This good MWCNT dispersion of LC-PP would cause better bulk electrical conductivity, mechanical properties and thermal stability of MWCNTs/PP nanocomposite bipolar plates. In the MWCNTs/LC-PP system, the bulk electrical conductivities with various MWCNT contents all exceed 100 S cm -1. The flexural strength of the MWCNTs/LC-PP nanocomposite bipolar plate with 8 phr of MWCNTs was approximately 37% higher than that of the original nanocomposite bipolar plate and the unnotched Izod impact strength of MWCNTs/LC-PP nanocomposite bipolar plates was also increased from 68.32 J m -1 (0 phr) to 81.40 J m -1 (8 phr), increasing 19%. In addition, the coefficient of thermal expansion of MWCNTs/LC-PP nanocomposite bipolar plate was decreased from 32.91 μm m -1 °C -1 (0 phr) to 25.79 μm m -1 °C -1 (8 phr) with the increasing of MWCNT content. The polarization curve of MWCNTs/LC-PP nanocomposite bipolar plate compared with graphite bipolar plate was also evaluated. These results confirm that the addition of MWCNTs in LC-PP leads to a significant improvement on the cell performance of the nanocomposite bipolar plate.

  15. Electrolytes Test

    Science.gov (United States)

    ... mean? High or low electrolyte levels can be caused by several conditions and diseases. Generally, they are affected by how much is consumed in the diet and absorbed by the body, the amount of water in a person's body, and the amount eliminated ...

  16. 电解氧化法从葡萄糖制备D-葡萄糖酸-δ-内酯%Preparation of D-Gluconic Acid-S-Lactone by Electrolytic Oxidation of Glucose

    Institute of Scientific and Technical Information of China (English)

    周永江

    2011-01-01

    文章用自制压滤式电解槽对葡萄糖进行氧化电解制备D-葡萄糖酸-δ-内酯,对其工艺条件如电解质溶液、工作电流、分离、结晶条件等进行了一系列的探索和研究。结果表明,采用电解液外循环,控制一定的工作电流,可以得到较高产率的葡萄糖酸,再用电渗析方法分离葡萄糖和葡萄糖酸液溶液后,经过离子交换树脂,结晶,浓缩可以得到最终产物。%In the paper,D-gluconic acid-δ-lactone is Prepared from electrolytic oxidation of glucose by self-made filter press type electrolytic cell.Technological conditions such as electrolyte solution,operating current,separation and crystallization conditions are explored and researched.The results show that by external circulating electrolyte solution and by controlling certain operating current,more higher yields of gluconic acid can be obtained.After separating the glucose and gluconic acid solution by electrodialysis,the obtained acid solution through ion exchange resins is crystallined and then is concentrated to the final product.

  17. Cone-shaped cylindrical Ce0.9Gd0.1O1.95 electrolyte prepared by slip casting and its application to solid oxide fuel cells

    Institute of Scientific and Technical Information of China (English)

    SUI Jing; DONG Lifeng; LIU Jiang

    2012-01-01

    A cone-shaped gadolinium doped ceria (Ce0.9Gd0.1O1.95,GDC) electrolyte cylinder with a thin wall was fabricated using slip casting technique.The diameter of the larger open end of the cone-shaped cylinder was 0.85 cm,the length was 1.0 cm,and the thickness of the wall was 0.026 cm after sintering.Both the electrolyte and electrode powders were fabricated by using a glycine-nitrate process.A single solid oxide fuel cell (SOFC) was prepared with the cone-shaped electrolyte,NiO-GDC (70:30 wt.%) anode and Sm0.5Sr0.5CoO3 (SSC) cathode.Its electrochemical performance (Ⅰ- Ⅴcurve) and electrochemical impedance spectroscopy (EIS) were studied with humidified hydrogen as the fuel and air as the oxidant.The maximum output power density was about 300 mW/cm2 at 700 ℃.The EIS results showed that the dominant loss of the SOFC was from the ohmic resistance of the electrolyte.

  18. Preparation and properties of PVP/PVDF-HFP microporous polymer electrolyte%PVP/PVDF-HFP微孔聚合物电解质的制备及性能

    Institute of Scientific and Technical Information of China (English)

    杨波; 李新海; 郭华军; 王志兴; 黄思林; 李勇勇

    2012-01-01

    以聚偏氟乙烯-六氟丙烯(PVDF-HFP)和聚乙烯基吡咯烷酮(PVP)为基质材料,采用倒相法,在不同的PVP∶PVDF-HFP配比下合成PVP/PVDF-HFP微孔聚合物电解质膜,将制备的微孔膜浸入电解液中活化得到了一系列锂离子电解质膜,并通过扫描电镜、力学、红外光谱进行能分析.研究结果表明:所制备的微孔聚合物电解质膜在PVP∶PVDF-HFP配比(质量比)为0.2∶1时综合性能最好,其吸液率为210%,抗拉强度为2.86N/mm2,电导率为1.82×10-3S/cm,电化学稳定窗口为5.7V.%PVP/PVDF-HFP micropores membranes based on PVDF-HFP and PVP were prepared by the phase transfer method with different mass ratios of PVP to PVDF-HFP. The membranes were characterized by means of SEM, FTIR, AC impedance and linear scan voltammetry methods. The results show that the optimium mass ratio of PVP to PVDF-HFP is 0.2:1. The liquid absorption rate of the polymer electrolyte is 210%. It shows a good tensile strength of 2.86 N/mm2. The ionic conductivity is 1.82 × 10-3 S/cm, and the electrochemical stable window is S.7 V.

  19. Preparation and Electrical Property of Ba1.03Ce0.8Ho0.2O3-α Solid Electrolyte

    Institute of Scientific and Technical Information of China (English)

    WANG, Maoyuan; QIU, Ligan; SUN, Yufeng

    2009-01-01

    Ba1.03Ce0.8Ho0.2O3-α solid electrolyte with nonstoichiometric composition was prepared by high temperature solid-state reaction. Phase composition, surface and fracture morphologies of the material were characterized by using XRD and SEM, respectively. Ionic transport number and conductivity of the material were measured by gas concentration cell and ac impedance spectroscopy methods in the temperature range of 600-1000 ℃ in dry air, wet air and wet hydrogen, respectively. Ionic conduction was researched and compared with those of BaCe0.8Ho0.2O3-α and Ba0.970.8Ho0.2O3-α. The results indicate that Ba1.03Ce0.8Ho0.2O3-α is a single-phase perovskite-type orthorhombic system. In the temperature range of 600-1000 ℃, it is a mixed conductor of oxide ion and electron hole with the oxide ionic transport number of 0.10-0.36 in dry air atmosphere, a mixed conductor of proton, oxide ion and electronic hole with the protonic transport number of 0.11-0.01 and the oxide ionic trans- port number of 0.34-0.30 in wet air atmosphere, and a pure protonic conductor with the protonic transport number ionic conduction is superior to that of BaCe0.8Ho0.2O3-α and Ba0.97Ce0.8Ho0.2O3-α under the experimental conditions.

  20. Preparation and characterisation of porous poly(2,5benzimidazole) (ABPBI) membranes using surfactants as templates for polymer electrolyte membrane fuel cells

    CSIR Research Space (South Africa)

    Zheng, H

    2010-04-01

    Full Text Available properties on mechanical strengths, thermal stability and electrochemical performance when compared with those of the original ABPBI membrane, suggestive of a promising polymer electrolyte for fuel cells at high temperature....

  1. 直接涂膜技术用于质子交换膜燃料电池膜电极制备%MEA PREPARATION FOR POLYMER ELECTROLYTE MEMBRANE FUEL CELL BY APPLYING DIRECTLY PRINTING CATALYST ON MEMBRANE TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    蒋淇忠; 马紫峰; Oumarou Savadogo

    2004-01-01

    A new membrane electrolyte assembly (MEA) preparation method for polymer electrolyte membrane fuel cell (PEMFC) was developed by applying the directly printing catalyst on membrane technique. This method was simple and easy to be controlled as verified by repetition experiment. When the membrane with catalyst prepared by the new technique and the electrode with diffusion layer was only sandwiched but not hot pressed, this kind of MEA was called not-hot-press MEA (NPMEA) and its fuel cell performance was better than that of MEA which was hot pressed (HPMEA). The effects of 6 different kinds of solvents in catalyst mixture ink on the performance of fuel cell were assessed. It was discovered that iso-propanol was the best solvent in catalyst mixture ink and showed the best performance of fuel cell. Finally several MEAs prepared by different ways were tested on fuel cell station and it was reported that the performance of MEA prepared by the directly printing catalyst on membrane technique was the best in the whole voltage region.

  2. Effect of electrolytes nature and concentration on the morphology and structure of MoS{sub 2} nanomaterials prepared using one-pot solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Akram, H., E-mail: akramhanane@yahoo.fr [Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Laboratoire de Génie Chimique et Valorisation des Ressources, Faculté des Sciences et Techniques de Tanger, Université Abdelmalek Essâadi, B.P. 416 Tangier (Morocco); Mateos-Pedrero, C., E-mail: cmpedrero@yahoo.es [Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculdade de Engenharia da Universidade do Porto Rua Roberto Frias, s/n4200-465, Porto (Portugal); Gallegos-Suárez, E.; Guerrero-Ruíz, A. [Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Grupo de Diseño y Aplicación de Catalizadores Heterogéneos, Unidad Asociada UNED—ICP (CSIC), Madrid (Spain); Chafik, T. [Laboratoire de Génie Chimique et Valorisation des Ressources, Faculté des Sciences et Techniques de Tanger, Université Abdelmalek Essâadi, B.P. 416 Tangier (Morocco); Rodríguez-Ramos, I. [Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Grupo de Diseño y Aplicación de Catalizadores Heterogéneos, Unidad Asociada UNED—ICP (CSIC), Madrid (Spain)

    2014-07-01

    Different MoS{sub 2} nanostructures have been obtained following an innovative one-step solvothermal method by changing the concentration and type of the electrolyte while avoiding the use of surfactant. It was found that the chemical nature of the studied electrolyte ((NH{sub 4}){sub 2}CO{sub 3} or KCl) do not significantly affect the morphology and structure of the obtained MoS{sub 2} nanomaterials. Nevertheless, increasing the electrolyte concentration yields to a remarkable modification of the morphology of the resulting MoS{sub 2} from nanospheres to worm-shaped then finally to nanotubes. All the obtained nanomaterials were characterized by X-ray diffraction, (XRD), transmission electron microscopy (TEM, HRTEM), Fourier transformation infra-red spectroscopy (FTIR), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS).

  3. Organic/inorganic nanocomposite polymer electrolyte

    Institute of Scientific and Technical Information of China (English)

    Li Qi; Shao Jun Dong

    2007-01-01

    The organic/inorganic nanocomposites polymer electrolytes were designed and synthesized. The organic/inorganic nanocom posites membrane materials and their lithium salt complexes have been found thermally stable below 200 ℃. The conductivity of the organic/inorganic nanocomposites polymer electrolytes prepared at room temperature was at magnitude range of 10-6 S/cm.

  4. Electrolytic fixer.

    Science.gov (United States)

    Stevens

    1982-12-01

    Interest in the recovery of silver from radiographic film generates a need to understand the operating procedures of recovery units utilizing the electrolytic fixer principle. Tailing or terminal units and recirculation units using electrolysis are evaluated. Difficulties encountered in the number of Coulombs applied to a specific amount of fixer are discussed. Reduction of sulfiding as a result of electrolysis and variations in film volumes are noted. The quantity and quality of silver collected can be improved by being aware of alterations in chemical activity used in a silver recovery program.

  5. Microstructured Electrolyte Membranes to Improve Fuel Cell Performance

    Science.gov (United States)

    Wei, Xue

    Fuel cells, with the advantages of high efficiency, low greenhouse gas emission, and long lifetime are a promising technology for both portable power and stationary power sources. The development of efficient electrolyte membranes with high ionic conductivity, good mechanical durability and dense structure at low cost remains a challenge to the commercialization of fuel cells. This thesis focuses on exploring novel composite polymer membranes and ceramic electrolytes with the microstructure engineered to improve performance in direct methanol fuel cells (DMFCs) and solid oxide fuel cells (SOFCs), respectively. Polymer/particle composite membranes hold promise to meet the demands of DMFCs at lower cost. The structure of composite membranes was controlled by aligning proton conducting particles across the membrane thickness under an applied electric field. The field-induced structural changes caused the membranes to display an enhanced water uptake, proton conductivity, and methanol permeability in comparison to membranes prepared without an applied field. Although both methanol permeability and proton conductivity are enhanced by the applied field, the permeability increase is relatively lower than the proton conductivity improvement, which results in enhanced proton/methanol selectivity and improved DMFC performance. Apatite ceramics are a new class of fast ion conductors being studied as alternative SOFC electrolytes in the intermediate temperature range. An electrochemical/hydrothermal deposition method was developed to grow fully dense apatite membranes containing well-developed crystals with c-axis alignment to promote ion conductivity. Hydroxyapatite seed crystals were first deposited onto a metal substrate electrochemically. Subsequent ion substitution during the hydrothermal growth process promoted the formation of dense, fully crystalline films with microstructure optimal for ion transport. The deposition parameters were systematically investigated, such as

  6. Dense topological spaces and dense continuity

    Science.gov (United States)

    Aldwoah, Khaled A.

    2013-09-01

    There are several attempts to generalize (or "widen") the concept of topological space. This paper uses equivalence relations to generalize the concept of topological space via the concept of equivalence relations. By the generalization, we can introduce from particular topology on a nonempty set X many new topologies, we call anyone of these new topologies a dense topology. In addition, we formulate some simple properties of dense topologies and study suitable generalizations of the concepts of limit points, closeness and continuity, as well as Jackson, Nörlund and Hahn dense topologies.

  7. Preparation of Electrolytic Manganese Residue Composite Cementing Material%电解锰渣复合胶凝材料的研制

    Institute of Scientific and Technical Information of China (English)

    王智; 高翠翠; 王庆珍

    2013-01-01

    Electrolytic manganese residue and calcined lime were used to stimulate the activity of the pozzolanic material of fly ash,and electrolytic manganese residue composite cementing material was researched and developed.The influence of electrolytic manganese residue and cement to composite cementing material was studied,and based on this,the optimal mix proportion was concluded.When the mass ratio of electrolytic manganese residue,fly ash,lime and cement was 50 ∶ 30 ∶ 10 ∶ 10,water to binder ratio was 0.55,28 d flexural,compressive strength of electrolytic manganese residue composite cementing material were 2.50 MPa,10.05 MPa.%利用电解锰渣和生石灰激发火山灰质材料粉煤灰的火山灰活性,制备电解锰渣复合胶凝材料.研究了电解锰渣和水泥对复合胶凝材料性能的影响,并在此基础上得出了最佳配合比,当电解锰渣复合胶凝材料中电解锰渣、粉煤灰、生石灰与水泥的质量比为50∶30∶ 10∶10,取水胶质量比为0.55,其28d抗折、抗压强度分别为2.50 MPa、10.05 MPa.

  8. Aluminium Electroplating on Steel from a Fused Bromide Electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Prabhat Tripathy; Laura Wurth; Eric Dufek; Toni Y. Gutknecht; Natalie Gese; Paula Hahn; Steven Frank; Guy Fredrickson; J Stephen Herring

    2014-08-01

    A quaternary bromide bath (LiBr-KBr-CsBr-AlBr3) was used to electro-coat aluminium on steel substrates. The electrolyte was prepared by the addition of AlBr3 into the eutectic LiBr-KBr-CsBr melt. A smooth, thick, adherent and shiny aluminium coating could be obtained with 80 wt.% AlBr3 in the ternary melt. The SEM photographs of the coated surfaces suggest the formation of thick and dense coatings with good aluminium coverage. Both salt immersion and open circuit potential measurement suggest that the coatings did display good corrosion-resistance behavior. Annealing of the coated surfaces, prior to corrosion tests, suggested the robustness of the metallic aluminium coating in preventing the corrosion of the steel surfaces. Studies also indicated that the quaternary bromide plating bath can potentially provide a better aluminium coating on both ferrous and non-ferrous metals, including complex surfaces/geometries.

  9. Poly(N-isopropylacrylamide) thin films densely grafted onto gold surface: preparation, characterization, and dynamic AFM study of temperature-induced chain conformational changes.

    Science.gov (United States)

    Montagne, Franck; Polesel-Maris, Jérome; Pugin, Raphael; Heinzelmann, Harry

    2009-01-20

    Thermally responsive poly(N-isopropylacrylamide) (PNIPAM) films are attracting considerable attention since they offer the possibility to achieve reversible control over surface wettability and biocompatibility. In this paper, we first report a new and simple method for the grafting under melt of amine-terminated PNIPAM chains onto gold surfaces modified with a self-assembled monolayer (SAM) of reactive thiols. The formation of homogeneous tethered PNIPAM films, whose thickness can be tuned by adjusting polymer molecular weight or SAM reactivity, is evidenced by using the combination of ellipsometry, X-ray photon spectroscopy, infrared spectroscopy (PM-IRRAS), and atomic force microscopy. The calculation of grafting parameters from experimental measurements indicated the synthesis of densely grafted PNIPAM films and allowed us to predict a "brushlike" regime for the chains in good solvent. In a second part, the temperature-induced responsive properties are studied in situ by conducting dynamic AFM measurements using the amplitude modulation technique. Imaging in water environment first revealed the reversible modification of surface morphology below and above the theoretical lower critical solution temperature (LCST) of PNIPAM. Then, the determination of amplitude and phase approach curves at various temperatures provided direct measurement of the evolution of the damping factor, or similarly the dissipated energy, as a function of the probe indentation into the PNIPAM film. Most interestingly, we clearly showed the subtle and progressive thermally induced chain conformational change occurring at the scale of several nanometers around the expected LCST.

  10. An Investigation into the Corrosion Behavior of MgO/ZrO2 Nanocomposite Coatings Prepared by Plasma Electrolytic Oxidation on the AZ91 Magnesium Alloy

    Science.gov (United States)

    Eslamzadeh, Nasrollah; Ebrahimi-Kahrizsangi, Reza; Karbasi, Saeed; Zarebidaki, Arman; Gharavi, Farhad

    2017-09-01

    Plasma electrolytic oxidation (PEO) of AZ91 Mg alloys was performed in ZrO2 nanoparticles containing Na2SiO3-based electrolytes. The phase composition and the microstructure of PEO coatings were analyzed by x-ray diffraction and scanning electron microscopy followed by energy dispersive spectroscopy. Pitting corrosion properties of the coatings were investigated using cyclic polarization and electrochemical impedance spectroscopy tests in a Ringer solution. The results showed the better pitting corrosion resistance of the composite coating, as compared to the oxide one, due to the thickened inner layer and the decrease in the surface defects of the composite coating. Also, the PEO process decreased the corrosion current density from 25.06 µA/cm2 in the Mg alloy to 2.7 µA/cm2 in the oxide coating and 0.47 µA/cm2 in the composite coating.

  11. Preparation of Transition Elements Doped Solid Electrolyte and Its Electrical Properties%过渡元素掺杂固体电解质的制备及电性能

    Institute of Scientific and Technical Information of China (English)

    李文昭; 黄志良; 陈常连; 陈娟; 夏红亮

    2016-01-01

    为了解决固体氧化物电解质在中温范围(500℃~800℃)工作电导效果不佳的问题,采用燃烧合成方法以氧化镧及过渡离子氧化物为原料,制备了过渡金属元素掺杂的硅酸镧体系电解质材料.用X-射线衍射图谱、扫描电子显微镜以及红外光谱对所得电解质进行了物相和显微结构分析.研究表明,掺杂离子对电解质的物相结构及形貌影响很小,但是通过引入适量过渡掺杂离子,能够有效提高电解质的电导率.当掺杂量摩尔比x=1.0时,锌掺杂后硅酸镧电解质具有最高的离子电导率,在500℃时的电导率可达2.106×10-2 S/cm.相比于未掺杂电解质在500℃电导率为1.71×10-3 S/cm有了显著提升.元素铜的掺入对电解质的致密度有促进作用,压片和二次烧结后电解质的密度达94.1%.同时通过交流阻抗测试分析证实镍在硅位掺杂会降低电解质的电导率.%To improve the ionic conductivity of solid oxide electrolyte at the middle temperatures of 500℃-800℃, we synthesized the solid oxide electrolyte of apatite type lanthanum silicate by combustion method using La2O3 and transition oxide as raw materials. The phase and microscopic structure of as-prepared electro⁃lytes were investigated by X-ray diffraction, scanning election microscopy and infrared spectroscopy. The results show that the ionic conductivity of electrolyte is effectively improved with proper amount of transition ion doping. And the effects of transition ion dopants on crystal structure, phase and morphology of apatite type lanthanum silicate are minimal. The electrolyte doped with zinc reaches the highest ionic conductivity of 2.106 × 10-2 S/cm at 500 ℃ when the doping molar ratio is 1.0, showing a significant increase of electronic conductivity compared to un-doped electrolyte of 1.71 × 10-3 S/cm at the same temperature. The relative density of apatite type lanthanum silicate electrolyte is promoted by

  12. Polymeric electrolytes for ambient temperature lithium batteries

    Science.gov (United States)

    Farrington, G. C.

    1987-09-01

    During this reporting period a number of novel solid polymer electrolytes formed by salts of multivalent cations and polyethylene oxide (PEO) have been prepared and characterized. These materials are of interest not only because of their potential ionic conductivities, but also because some of them may have electronic conductivity and oxidizing power which would be useful for novel electrode materials in all-solid-state batteries. Two broad classes of materials were investigated: PEO solutions of Zn(2), Cd(2), and Pb(2), all of which are potential electrolytes for solid-state batteries, and PEO solutions of transition metal salts, which are of interest as possible cathode materials. Mixed compositions containing both divalent cations and lithium ions were also prepared. Electrolytes formed with small, highly-polarizing ions, such as Mg(2) and Ca(2), are essentially pure anion conductors. Electrolytes containing Zn(2) behave similarly, unless they are hydrated, in which case the Zn(2) ions are quite mobile. Electrolytes formed with larger, more polarizable cations, such as Pb(2) and Cd(2), conduct both anions and cations. Solutions of salts of transition metal cations form a third group of electrolytes. Of the electrolytes investigated so far, those formed with Ni(++) salts are the most unusual. It appears as if the transport number of Ni(2) and the electrolyte conductivity can be greatly enhanced by controlling the hydration and dehydration of the polymer.

  13. Aqueous Chemical Solution Deposition of Novel, Thick and Dense Lattice-Matched Single Buffer Layers Suitable for YBCO Coated Conductors: Preparation and Characterization

    Directory of Open Access Journals (Sweden)

    Isabel van Driessche

    2012-09-01

    Full Text Available In this work we present the preparation and characterization of cerium doped lanthanum zirconate (LCZO films and non-stoichiometric lanthanum zirconate (LZO buffer layers on metallic Ni-5% W substrates using chemical solution deposition (CSD, starting from aqueous precursor solutions. La2Zr2O7 films doped with varying percentages of Ce at constant La concentration (La0.5CexZr1−xOy were prepared as well as non-stoichiometric La0.5+xZr0.5−xOy buffer layers with different percentages of La and Zr ratios. The variation in the composition of these thin films enables the creation of novel buffer layers with tailored lattice parameters. This leads to different lattice mismatches with the YBa2Cu3O7−x (YBCO superconducting layer on top and with the buffer layers or substrate underneath. This possibility of minimized lattice mismatch should allow the use of one single buffer layer instead of the current complicated buffer architectures such as Ni-(5% W/LZO/LZO/CeO2. Here, single, crack-free LCZO and non-stoichiometric LZO layers with thicknesses of up to 140 nm could be obtained in one single CSD step. The crystallinity and microstructure of these layers were studied by XRD, and SEM and the effective buffer layer action was studied using XPS depth profiling.

  14. Dense with Sense

    Science.gov (United States)

    Aletras, Anthony H.; Ingkanisorn, W. Patricia; Mancini, Christine; Arai, Andrew E.

    2005-09-01

    Displacement encoding with stimulated echoes (DENSE) with a low encoding strength phase-cycled meta-DENSE readout and a two fold SENSE acceleration ( R = 2) is described. This combination reduces total breath-hold times for increased patient comfort during cardiac regional myocardial contractility studies. Images from phantoms, normal volunteers, and a patient are provided to demonstrate the SENSE-DENSE combination of methods. The overall breath-hold time is halved while preserving strain map quality.

  15. Photo-induced properties of non-annealed anatase TiO{sub 2} mesoporous film prepared by anodizing in the hot phosphate/glycerol electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, Yoshiaki [Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628 (Japan); Tsuji, Etsushi, E-mail: e-tsuji@eng.hokudai.ac.jp [Division of Materials Chemistry, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628 (Japan); Aoki, Yoshitaka; Habazaki, Hiroki [Division of Materials Chemistry, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628 (Japan)

    2012-10-01

    Highlights: Black-Right-Pointing-Pointer The TiO{sub 2} mesoporous film can be formed by anodizing of titanium specimens in the hot phosphate/glycerol electrolyte. Black-Right-Pointing-Pointer The mesoporous film formed at 20 V without annealing was a mixture of amorphous phase and nanograined anatase, which clearly showed strong Left-Pointing-Angle-Bracket 0 0 1 Right-Pointing-Angle-Bracket preferred orientation. Black-Right-Pointing-Pointer Even without annealing, the as-anodized anatase TiO{sub 2} mesoporous film showed high photocatalytic activities for decomposition of water and methylene blue. Black-Right-Pointing-Pointer The as-anodized anatase TiO{sub 2} mesoporous film also showed superhydrophilicity with UV light irradiation. - Abstract: In this study, anatase crystalline TiO{sub 2} mesoporous film was formed by anodizing of titanium specimens without annealing procedures. The specimens were anodized at 3 and 20 V in 0.6 mol dm{sup -3} K{sub 2}HPO{sub 4} and 0.2 mol dm{sup -3} K{sub 3}PO{sub 4}/glycerol electrolyte at 433 K. The obtained films had mesoporous structures with pore diameters as small as {approx}10 nm. The mesoporous film formed at 20 V without annealing (MP-20V) was a mixture of amorphous phase and nanograined anatase, which clearly showed strong Left-Pointing-Angle-Bracket 0 0 1 Right-Pointing-Angle-Bracket preferred orientation, whereas that at 3 V was completely amorphous. Even without annealing, the MP-20V showed high photocatalytic activities for decomposition of water and methylene blue. In contrast, the anodic TiO{sub 2} nanotube film formed in NH{sub 4}F/ethylene glycol electrolyte revealed photocatalytic activities only after annealing at 723 K, because of the amorphous nature of the as-anodized nanotube film. The MP-20V film also showed superhydrophilicity with UV light irradiation.

  16. Solid state electrolyte systems

    Energy Technology Data Exchange (ETDEWEB)

    Pederson, L.R.; Armstrong, B.L.; Armstrong, T.R. [Pacific Northwest Lab., Richland, WA (United States)] [and others

    1997-12-01

    Lanthanum gallates are a new family of solid electrolytes that exhibit high ionic conductivity and are stable to high temperatures. Compositions have been developed that are as much as a factor of two more conductive than yttria-stabilized zirconia at a given temperature, through partial replacement of lanthanum by calcium, strontium, and/or barium and through partial replacement of gallium by magnesium. Oxide powders were prepared using combustion synthesis techniques developed in this laboratory; these were sintered to >95% of theoretical density and consisted of a single crystalline phase. Electrical conductivities, electron and ion transference numbers, thermal expansion, and phase behavior were evaluated as a function of temperature and oxygen partial pressure. A key advantage of the use of lanthanum gallate electrolytes in solid oxide fuel cells is that the temperature of operation may be lowered to perhaps 800 C, yet provide approximately the same power density as zirconia-based cells operating at 1000 C. Ceramic electrolytes that conduct both oxygen ions and electrons are potentially useful to passively separate pure oxygen from an air source at low cost. In such materials, an oxygen ion flux in one direction is charge-compensated by an opposing electron flux. The authors have examined a wide range of mixed ion and electron conducting perovskite ceramics in the system La{sub 1{minus}x}M{sub x}Co{sub 1{minus}y{minus}z}Fe{sub y}N{sub z}O{sub 3{minus}{delta}}, where M = Sr, Ca, and Ba, and N = Pr, Mn, Ni, Cu, Ti, and Al, as well as mixed conducting brownmillerite ceramics, and have characterized oxygen permeation behavior, defect chemistry, structural and phase stability, and performance as cathodes.

  17. Preparation of novel carbon microfiber/carbon nanofiber-dispersed polyvinyl alcohol-based nanocomposite material for lithium-ion electrolyte battery separator.

    Science.gov (United States)

    Sharma, Ajit K; Khare, Prateek; Singh, Jayant K; Verma, Nishith

    2013-04-01

    A novel nanocomposite polyvinyl alcohol precursor-based material dispersed with the web of carbon microfibers and carbon nanofibers is developed as lithium (Li)-ion electrolyte battery separator. The primary synthesis steps of the separator material consist of esterification of polyvinyl acetate to produce polyvinyl alcohol gel, ball-milling of the surfactant dispersed carbon micro-nanofibers, mixing of the milled micron size (~500 nm) fibers to the reactant mixture at the incipience of the polyvinyl alcohol gel formation, and the mixing of hydrophobic reagents along with polyethylene glycol as a plasticizer, to produce a thin film of ~25 μm. The produced film, uniformly dispersed with carbon micro-nanofibers, has dramatically improved performance as a battery separator, with the ion conductivity of the electrolytes (LiPF6) saturated film measured as 0.119 S-cm(-1), approximately two orders of magnitude higher than that of polyvinyl alcohol. The other primary characteristics of the produced film, such as tensile strength, contact angle, and thermal stability, are also found to be superior to the materials made of other precursors, including polypropylene and polyethylene, discussed in the literature. The method of producing the films in this study is novel, simple, environmentally benign, and economically viable.

  18. Preparation of NiO-YSZ/YSZ bi-layers for solid oxide fuel cells by electrophoretic deposition

    Science.gov (United States)

    Besra, Laxmidhar; Zha, Shaowu; Liu, Meilin

    A simple and cost-effective method, starting with electrophoretic deposition (EPD) on a carbon sheet, has been developed for preparation of a NiO-YSZ anode and thin, gas-tight YSZ electrolyte layer on it for use in solid oxide fuel cells (SOFCs). The innovative feature of this approach enables the deposition of anode materials as well as the YSZ electrolyte, which were subsequently co-fired in air at high temperatures to remove the carbon and form an anode-supported dense YSZ electrolyte. A functional SOFC constructed by brush painting a layer of mixed cathode consisting of La 0.8Sr 0.2MnO 3 (LSM) and YSZ on the electrolyte layer followed by firing at 1250 °C, displayed a peak power density of 434 mW cm -2 at 800 °C when tested with H 2 as fuel and ambient air as oxidant.

  19. Atoms in dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    More, R.M.

    1986-01-01

    Recent experiments with high-power pulsed lasers have strongly encouraged the development of improved theoretical understanding of highly charged ions in a dense plasma environment. This work examines the theory of dense plasmas with emphasis on general rules which govern matter at extreme high temperature and density. 106 refs., 23 figs.

  20. Quantum dense key distribution

    CERN Document Server

    Degiovanni, I P; Castelletto, S; Rastello, M L; Bovino, F A; Colla, A M; Castagnoli, G C

    2004-01-01

    This paper proposes a new protocol for quantum dense key distribution. This protocol embeds the benefits of a quantum dense coding and a quantum key distribution and is able to generate shared secret keys four times more efficiently than BB84 one. We hereinafter prove the security of this scheme against individual eavesdropping attacks, and we present preliminary experimental results, showing its feasibility.

  1. High Capacity, Superior Cyclic Performances in All-Solid-State Lithium-Ion Batteries Based on 78Li2S-22P2S5 Glass-Ceramic Electrolytes Prepared via Simple Heat Treatment.

    Science.gov (United States)

    Zhang, Yibo; Chen, Rujun; Liu, Ting; Shen, Yang; Lin, Yuanhua; Nan, Ce-Wen

    2017-08-30

    Highly Li-ion conductive 78Li2S-22P2S5 glass-ceramic electrolytes were prepared by simple heat treatment of the glass phase obtained via mechanical ball milling. A high ionic conductivity of ∼1.78 × 10(-3) S cm(-1) is achieved at room temperature and is attributed to the formation of a crystalline phase of high lithium-ion conduction. All-solid-state lithium-ion batteries based on these glass-ceramic electrolytes are assembled by using Li2S nanoparticles or low-cost commercially available FeS2 as active cathode materials and Li-In alloys as anode. A high discharge capacity of 535 mAh g(-1) is achieved after at least 50 cycles for the all-solid-state cells with Li2S as cathode materials, suggesting a rather high capacity retention of 97.4%. Even for the cells using low-cost FeS2 as cathode materials, same high discharge capacity of 560 mAh g(-1) is also achieved after at least 50 cycles. Moreover, the Coulombic efficiency remain at ∼99% for these all-solid-state cells during the charge-discharge cycles.

  2. Preparation and Lithium Ion Transport Behavior for Li1. 5 Al0. 5 Ge1. 5(PO4) 3 Based Solid Composite Electrolyte%Li1.5Al0.5Ge1.5(PO4)3基固体复合电解质的制备及锂离子导电行为

    Institute of Scientific and Technical Information of China (English)

    余涛; 韩喻; 王珲; 熊仕昭; 谢凯; 郭青鹏

    2016-01-01

    将聚氧化乙烯(PEO)和二(三氟甲基磺酰)亚胺锂(LiTFSI)混合(固定 EO/ Li 摩尔比为13)后,采用溶液浇注法制备了一系列不同 Li1.5 Al0.5 Ge1.5(PO4)3(LAGP)与 PEO 质量比的 LAGP-PEO(LiTFSI)固体复合电解质体系.结合电化学阻抗法、表面形貌表征以及与惰性陶瓷填料(SiO2, Al2 O3)性能的对比分析,探讨了LAGP 在固体复合电解质中的作用机理以及锂离子的导电行为.结果表明,在以 LAGP 为主相的固体复合电解质中, PEO 主要处于无定形态,整个体系主要为 PEO 与 LiTFSI 的络合相、 LAGP 与 PEO(LiTFSI)相互作用形成的过渡相和 LAGP 晶相.其中 LAGP 作为主要的导电基体不仅起到降低 PEO 结晶度、改善两相导电界面的作用;同时自身也可以作为离子传输的通道,降低锂离子迁移的活化能,从而使离子电导率得到提高.当LAGP 与 PEO 的质量比为6:4时,固体复合电解质的成膜性能最好,离子电导率最高,在30℃时为2.57×10-5 S/ cm,接近 LAGP 的水平,电化学稳定窗口超过5 V.%LAGP-PEO ( LiTFSI) solid composite electrolyte were prepared with Li1. 5 Al0. 5 Ge1. 5 ( PO4 ) 3 (LAGP) and LiN( CF3 SO2 ) 2 ( LiTFSI) as conductive components and poly( ethylene oxide) ( PEO) as the binder using solution casting method. The molar ratio of EO/ Li was 13 when the ratio of PEO to LAGP was varied. The role of LAGP and the transport mechanism of Li-ion in solid composite electrolyte were analyzed using electrochemical impedance spectroscopy and morphology techniques. The results showed that LAGP partially interacted to PEO(LiTFSI) and uniformly distributed in the electrolyte. With the increase of LAGP content, amorphous regions of PEO rises up to a maximum value due to the coordination interactions between LAGP and PEO(LiTFSI). Three phases are generally present, namely a pure crystalline LAGP phase, all amorphous complexion PEO( LiTFSI) phase and a transition phase consisting of lithium salt

  3. New electrolytes and electrolyte additives to improve the low temperature performance of lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiao-Qing

    2008-08-31

    In this program, two different approaches were undertaken to improve the role of electrolyte at low temperature performance - through the improvement in (i) ionic conductivity and (ii) interfacial behavior. Several different types of electrolytes were prepared to examine the feasibil.ity of using these new electrolytes in rechargeable lithium-ion cells in the temperature range of +40°C to -40°C. The feasibility studies include (a) conductivity measurements of the electrolytes, (b) impedance measurements of lithium-ion cells using the screened electrolytes with di.fferent electrochemical history such as [(i) fresh cells prior to formation cycles, (ii) after first charge, and (iii) after first discharge], (c) electrical performance of the cells at room temperatures, and (d) charge discharge behavior at various low temperatures. Among the different types of electrolytes investigated in Phase I and Phase II of this SBIR project, carbonate-based LiPF6 electrolytes with the proposed additives and the low viscous ester as a third component to the carbonate-based LiPF6 electrolytes show promising results at low temperatures. The latter electrolytes deliver over 80% of room temperature capacity at -20{degrees}C when the lithium-ion cells containing these electrolytes were charged at -20 °C. Also, there was no lithium plating when the lithium­-ion cells using C-C composite anode and LiPF{sub 6} in EC/EMC/MP electrolyte were charged at -20{degrees}C at C/5 rate. The studies of ionic conductivity and AC impedance of these new electrolytes, as well as the charge discharge characteristics of lithium-ion cells using these new electrolytes at various low temperatures provide new findings: The reduced capacity and power capability, as well as the problem of lithium plating at low temperatures charging of lithium-ion cells are primarily due to slow the lithium-ion intercalation/de-intercalation kinetics in the carbon structure.

  4. Preparation of NASICON-Type Nanosized Solid Electrolyte Li1.4Al0.4Ti1.6(PO4)3 by Evaporation-Induced Self-Assembly for Lithium-Ion Battery.

    Science.gov (United States)

    Liu, Xingang; Fu, Ju; Zhang, Chuhong

    2016-12-01

    A simple and practicable evaporation-induced self-assembly (EISA) method is introduced for the first time to prepare nanosized solid electrolyte Li1.4Al0.4Ti1.6(PO4)3 (LATP) for all-solid-state lithium-ion batteries. A pure Na(+) super ion conductor (NASICON) phase is confirmed by X-ray diffraction (XRD) analysis, and its primary particle size is down to 70 nm by optimizing evaporation rate of the solvent. Excellent room temperature bulk and total lithium-ion conductivities of 2.09 × 10(-3) S cm(-1) and 3.63 × 10(-4) S cm(-1) are obtained, with an ion-hopping activation energy as low as 0.286 eV.

  5. Direct ceramic inkjet printing of yttria-stabilized zirconia electrolyte layers for anode-supported solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Tomov, R.I.; Hopkins, S.C. [Applied Superconductivity and Cryoscience Group, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB4 3QZ (United Kingdom); Krauz, M.; Kluczowski, J.R. [Institute of Power Engineering, Ceramic Department CEREL, 36-040 Boguchwala (Poland); Jewulski, J. [Institute of Power Engineering, Fuel Cells Department, 02-981 Warsaw (Poland); Glowacka, D.M. [Detector Physics Group, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom); Glowacki, B.A. [Applied Superconductivity and Cryoscience Group, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB4 3QZ (United Kingdom); Institute of Power Engineering, Fuel Cells Department, 02-981 Warsaw (Poland)

    2010-11-01

    Electromagnetic drop-on-demand direct ceramic inkjet printing (EM/DCIJP) was employed to fabricate dense yttria-stabilized zirconia (YSZ) electrolyte layers on a porous NiO-YSZ anode support from ceramic suspensions. Printing parameters including pressure, nozzle opening time and droplet overlapping were studied in order to optimize the surface quality of the YSZ coating. It was found that moderate overlapping and multiple coatings produce the desired membrane quality. A single fuel cell with a NiO-YSZ/YSZ ({proportional_to}6 {mu}m)/LSM + YSZ/LSM architecture was successfully prepared. The cell was tested using humidified hydrogen as the fuel and ambient air as the oxidant. The cell provided a power density of 170 mW cm{sup -2} at 800 C. Scanning electron microscopy (SEM) revealed a highly coherent dense YSZ electrolyte layer with no open porosity. These results suggest that the EM/DCIJP inkjet printing technique can be successfully implemented to fabricate electrolyte coatings for SOFC thinner than 10 {mu}m and comparable in quality to those fabricated by more conventional ceramic processing methods. (author)

  6. Preparation and characterization on nano-hybrid composite solid polymer electrolyte of PVdF-HFP /MG49-ZrO2 for battery application

    Science.gov (United States)

    Lee T., K.; Ahmad, A.; Hasyareeda, N.

    2014-09-01

    Initial study on nano composite polymer electrolyte of PVdF-HFP/MG49-ZrO2 has been done. The zirconium was synthesis via in-situ sol-gel method in a dissolved polymer blends. The effects of different concentrations of zirconium and pH values have been investigated on nano composite polymer (NCP). Analysis impedance show that only at 6 wt. % of zirconium for all pH values show a semi-circle arc which have lowest value of bulk resistance. No ionic conductivity value is obtain due to the absent of ion charge carriers. Analysis of XRD revealed that crystallinity phase of the nano composite polymer was affect by different pH values. However, no significant changes have been observed in IR bands. This could well indicate that different pH medium did not affect the chemical bonding in the structure.

  7. Preparation and characterization on nano-hybrid composite solid polymer electrolyte of PVdF-HFP /MG49-ZrO{sub 2} for battery application

    Energy Technology Data Exchange (ETDEWEB)

    Lee, T. K.; Ahmad, A. [Polymer Research Center, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor D. E. Malaysia and School of Chemical Sciences and Food Technology, Faculty of Science and Technology (Malaysia); Hasyareeda, N. [School of Chemical Sciences and Food Technology, Faculty of Science and Technology (Malaysia)

    2014-09-03

    Initial study on nano composite polymer electrolyte of PVdF-HFP/MG49-ZrO{sub 2} has been done. The zirconium was synthesis via in-situ sol-gel method in a dissolved polymer blends. The effects of different concentrations of zirconium and pH values have been investigated on nano composite polymer (NCP). Analysis impedance show that only at 6 wt. % of zirconium for all pH values show a semi-circle arc which have lowest value of bulk resistance. No ionic conductivity value is obtain due to the absent of ion charge carriers. Analysis of XRD revealed that crystallinity phase of the nano composite polymer was affect by different pH values. However, no significant changes have been observed in IR bands. This could well indicate that different pH medium did not affect the chemical bonding in the structure.

  8. Effect of surface roughness on leakage current and corrosion resistance of oxide layer on AZ91 Mg alloy prepared by plasma electrolytic oxidation

    Science.gov (United States)

    Yoo, Bongyoung; Shin, Ki Ryoung; Hwang, Duck Young; Lee, Dong Heon; Shin, Dong Hyuk

    2010-09-01

    The influence of the surface roughness of Mg alloys on the electrical properties and corrosion resistance of oxide layers obtained by plasma electrolytic oxidation (PEO) were studied. The leakage current in the insulating oxide layer was enhanced by increasing the surface roughness, which is a favorable characteristic for the material when applied to hand-held electronic devices. The variation of corrosion resistance with surface roughness was also investigated. The corrosion resistance was degraded by the increasing surface roughness, which was confirmed with DC polarization and impedance spectroscopy. Pitting corrosion on the passive oxide layer was also analyzed with a salt spray test, which showed that the number of pits was not affected by the surface roughness when the spray time reached 96 h.

  9. Preparation

    Directory of Open Access Journals (Sweden)

    M.M. Dardir

    2014-03-01

    Full Text Available Some hexanamide-mono and di-linoleniate esters were prepared by the reaction of linolenic acid and hexanamide (derived from the reaction of hexanoic acid and diethanolamine. The chemical structure for the newly prepared hexanamide-mono and di-linoleniate esters were elucidated using elemental analysis, (FTIR, H 1NMR and chemical ionization mass spectra (CI/Ms spectroscopic techniques. The results of the spectroscopic analysis indicated that they were prepared through the right method and they have high purity. The new prepared esters have high biodegradability and lower toxicity (environmentally friendly so they were evaluated as a synthetic-based mud (ester-based mud for oil-well drilling fluids. The evaluation included study of the rheological properties, filtration and thermal properties of the ester based-muds formulated with the newly prepared esters compared to the reference commercial synthetic-based mud.

  10. Preparation and Characterization of PEO-LATP/LAGP Ceramic Composite Electrolyte Membrane for Lithium Batteries%锂离子电池PEO-LATP/LAGP陶瓷复合电解质膜的制备与性能表征

    Institute of Scientific and Technical Information of China (English)

    黄乐之; 温兆银; 靳俊; 刘宇

    2012-01-01

    设计并制备了PEO-LATP/LAGP陶瓷复合电解质.使用NASICON结构的Li1.4Al0.4Ti1.6(PO4)3 (LATP)或Li1.5Al0.5Ge1.5(PO4)3 (LAGP)作为陶瓷基体,以PEO为粘结剂,得到了均匀、厚度仅为20 μm的复合电解质膜.通过电化学性能表征发现当w(LATP/LAGP)∶w(PEO)=7∶3时,复合电解质膜具有最高的室温电导率,达到0.186 mS/cm(PEO-LATP)与0.111 mS/cm (PEO-LAGP).通过充放电循环实验表明,Li/复合电解质/LiCo1/3Ni1/3Mn1/3O2电池的首次放电容量达170 mAh/g.使用PEO-LATP复合电解质的电池在循环时有较大的容量衰减,而使用PEO-LAGP复合电解质则循环性能有明显的改善,在10次循环后仍保持在150 mAh/g.%A PEO-LATP/LAGP composite electrolyte for lithium batteries was designed and prepared. Uniformly composite electrolyte membrane with thickness of 20 μm was obtained by assembling Li1.4Al0.4Ti1.6(PO4)3 (LATP) or Li1.5Al0.5Ge1.5(PO4)3 (LAGP) as ceramic substrate and PEO as binder. Highest room-temperature conductivities were achieved for the sample prepared with w(ceramics):w(PEO)=7:3. Electrochemical analysis showed that the conductivity reached 0.186 mS/cm for PEO-LATP and 0.111 mS/cm for PEO-LAGP. Cycling performances of 170 mAh/g was obtained for the first discharge capacity of the Li/composite electrolyte/LiCo1/3Ni1/3Mn1/3O2 cell. Sharp decrease of cycling capacity was observed for the cell using PEO-LATP membrane. The cycling performance of the PEO-LAGP based cell was greatly improved with 150 mAh/g remained after 10 cycles.

  11. Impact resistant electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Veith, Gabriel M.; Armstrong, Beth L.; Tenhaeff, Wyatt E.; Dudney, Nancy J.

    2017-03-07

    A passively impact resistant composite electrolyte composition includes an electrolyte solvent, up to 2M of an electrolyte salt, and shear thickening ceramic particles having a polydispersity index of no greater than 0.1, an average particle size of in a range of 50 nm to 1 .mu.m, and an absolute zeta potential of greater than .+-.40 mV.

  12. Nanoporous polymer electrolyte

    Science.gov (United States)

    Elliott, Brian [Wheat Ridge, CO; Nguyen, Vinh [Wheat Ridge, CO

    2012-04-24

    A nanoporous polymer electrolyte and methods for making the polymer electrolyte are disclosed. The polymer electrolyte comprises a crosslinked self-assembly of a polymerizable salt surfactant, wherein the crosslinked self-assembly includes nanopores and wherein the crosslinked self-assembly has a conductivity of at least 1.0.times.10.sup.-6 S/cm at 25.degree. C. The method of making a polymer electrolyte comprises providing a polymerizable salt surfactant. The method further comprises crosslinking the polymerizable salt surfactant to form a nanoporous polymer electrolyte.

  13. 倒相法制备PVDF-HFP基复合微孔聚合物电解质%PVDF-HFP matrix complex micro-porous polymer electrolyte prepared by phase inversion method

    Institute of Scientific and Technical Information of China (English)

    刘辉; 顾大明; 白继元

    2012-01-01

    To improve the distribution properties of nanoparticles in the polymer electrolyte,micro-porous polymer electrolyte PVDF-HFP-SiO2(OP-10) was prepared with phase inversion method by adopting nano-sized SiO2 as the inorganic filler and OP-10 as dispersant.The morphology,crystal structure and electrochemical properties of the electrolyte were characterized by scanning electron microscope(SEM),X-ray diffraction(XRD),electrochemical impedance spectra(EIS).The results showed that the addition of nano-SiO2 suppressed the crystallinity of polymer electrolyte and enhanced the tensile intensity.The ionic conductivity was improved,the highest ionic conductivity(20 ℃) of the PVDF-HFP-SiO2(OP-10) polymer electrolyte was 4.90×10-3S·cm-1,with a high electrochemical stability window of 5.3 V,and the corresponding cation transference number was 0.83.The distribution of SiO2 and interfacial compatibility of nanometer particles were improved by the addition of OP-10.%为改善纳米粒子在聚合物电解质中的分散效果,采用倒相制膜法,以纳米SiO2为填料,以OP-10为分散剂,制备复合微孔聚偏氟乙烯-六氟丙烯基电解质PVDF-HFP-SiO2(OP-10).用SEM、XRD、交流阻抗法等测试手段对电解质的微观形貌、内部结构和电化学相关性能等进行表征,结果表明:SiO2的加入降低了聚合物电解质膜的结晶度,增强了电解质的拉伸强度,提高了PVDF-HFP-SiO2(OP-10)聚合物电解质的电导率,在20℃时,可达到4.90×10-3S.cm-1,电化学稳定窗口为5.3 V,电解质的离子迁移数为0.83.分散剂OP-10的加入改善了纳米SiO2与基质的界面相容性,改善了SiO2在基质中的分散度.

  14. 溶剂挥发法制备聚合物电解质P(VDF-HFP)/PVP及其性能%Preparation and characterization of polymer electrolyte P (VDF-HFP)/PVP by solvent evaporation method

    Institute of Scientific and Technical Information of China (English)

    袁艳; 陈白珍; 陈亚

    2013-01-01

    A kind of microporous membrane based on the blend of PVP and P (VDF-HFP) was prepared by solvent evaporation method, and the LiCoO 2/Li polymer batteries were assembled with the microporous membrane which absorbed electrolyte. The polymer membrane and electrolyte were characterized by scanning electronic morphology (SEM), differential scanning calorimeter-thermo gravimetry (DSC-TG), electrochemical impedance spectroscopy (EIS) and linear scanning voltammetry (LSV). The electrochemical performance of LiCoO2/Li polymer battery was tested by charge-discharge test with constant current. The results show that this polymer membrane has abundant micro pores and exhibits up to 480%uptake of liquid electrolyte. The ionic conductivity of the polymer electrolyte is 4.79×10-3 S/cm at room temperature and its electrochemical stable window is 5.5 V. The LiCoO2/Li battery based on the polymer electrolyte displays an initial discharge capacity of 142.37 mA∙h/g and discharge plateau of about 3.86 V at 0.1C. After 30 cycles, its discharge capacity remains 136.68 mA∙h/g, and coulombic efficiency stays around 97%.%以聚乙烯基吡咯烷酮(PVP)与聚偏氟乙烯-六氟丙烯[P(VDF-HFP)]的共混物为基质,通过溶剂挥发法制备聚合物微孔膜,将其浸取电解液后制成聚合物电解质并组装LiCoO 2/Li聚合物锂离子电池。采用扫描电子显微镜、差热-热重分析、交流阻抗、线性伏安扫描等技术对制备的聚合物微孔膜及电解质进行表征,采用恒流充放电方法对组装的聚合物锂离子电池进行电化学性能测试。结果表明:溶剂挥发法制得的聚合物膜孔穴丰富,液态电解质吸液率可达到480%;浸取电解液后获得的聚合物电解质室温离子电导率为4.79×10-3 S/cm,电化学稳定窗口为5.5 V;基于该聚合物电解质装配的LiCoO 2/Li电池在0.1C倍率充放电时,首次放电容量为142.37 mA∙h/g,放电平台约为3.86 V,30

  15. Electrochemical performance of nonflammable polymeric gel electrolyte containing triethylphosphate

    Energy Technology Data Exchange (ETDEWEB)

    Lalia, Boor Singh; Fujita, Takayoshi; Yoshimoto, Nobuko; Egashira, Minato; Morita, Masayuki [Graduate School of Science and Engineering, Yamaguchi University, 2-16-1 Tokiwadai, Ube 755-8611 (Japan)

    2009-01-01

    Nonflammable polymeric gel electrolyte has been prepared by immobilizing 1 M LiBF{sub 4}/EC + DEC + TEP (55:25:20, v/v/v, EC: ethylene carbonate, DEC: diethyl carbonate and TEP: triethylphosphate) solution in poly(vinylidene fluoride-co-hexafluoro propylene) (PVdF-HFP) where TEP acts as a fire-retardant solvent in the gel electrolyte. The polymeric gel electrolyte has a high value of ionic conductivity of 1.76 mS cm{sup -1} at 28 C. Thermal safety calorimetry (TSC) experiments show good thermal stability of the gel electrolyte. Cyclic voltammetry and charge/discharge cycling tests were performed on LiMn{sub 2}O{sub 4}/gel electrolyte and graphite/gel electrolyte half cells. The gel electrolyte works well for graphite/LiMn{sub 2}O{sub 4} cell although some improvement in the cycleability of the graphite electrode is still needed. (author)

  16. 电解腐蚀合成铋纳米粉的热氧化性%Thermal Oxidation Stability of Bi Nanoparticles Prepared by Electrolytic Corrosion

    Institute of Scientific and Technical Information of China (English)

    房国丽; 王雄

    2011-01-01

    以块体金属Bi为阳极牺牲材料,通过电化学腐蚀可以控制合成厚度为20~30 nm的准二维金属Bi纳米片,进一步在空气中热处理可以氧化生成Bi2O3.研究结果表明:所得Bi纳米片由于尺寸较小和比表面积较大,其热氧化温度相对于文献报道明显降低;而热处理温度是影响热氧化形成Bi2O3晶体结构的关键因素.%The quasi two dimensional Bi nanosheets have been controlled synthesized via electrolytic corrosion of bulk Bi. The obtained Bi nanosheets with 20~30 nm in thickness are thermally treated in air at different temperature, and the oxidation would take place in the process. Results show that the synthesized Bi nanosheets with smaller sizes and higher specific surface area need lower oxidation temperature, and the oxidation temperature is the key to the Bi2O3 crystal structures synthesized by thermal oxidation of the Bi nanosheets.

  17. A Randomized Prospective Study of Bowel Preparation for Colonoscopy with Low-Dose Sodium Phosphate Tablets versus Polyethylene Glycol Electrolyte Solution

    Directory of Open Access Journals (Sweden)

    Erina Kumagai

    2014-01-01

    Full Text Available Optimal bowel preparation is essential for the safety and outcome of colonoscopy. A solution containing polyethylene glycol (PEG is often used as a bowel cleansing agent, but some patients are intolerant of PEG, and this may lead to discontinuation of colonoscopy. Sodium phosphates (NaP tablets are designed to improve patient acceptance and compliance. The objective of this study was to compare bowel preparation efficiency and patient acceptance of a 30 NaP tablet preparation (L-NaP and a 2 L PEG preparation. Patients were randomized into either the L-NaP or PEG group. The primary endpoint was the efficiency of colon cleansing as assessed by a validated four-point scale according to the Aronchick scale by endoscopists and was verified by blinded investigators. The secondary endpoints were patients’ tolerability and acceptance. Colon-cleansing efficiency was not significantly different between the two preparations. However, patients’ overall judgment was significantly in favor of L-NaP, reflecting better acceptance of L-NaP than PEG. Additionally, more patients favored L-NaP over PEG in a hypothetical future occasion requiring colonoscopy.

  18. Lithium carbon batteries with solid polymer electrolyte; Accumulateur lithium carbone a electrolyte solide polymere

    Energy Technology Data Exchange (ETDEWEB)

    Andrieu, X.; Boudin, F. [Alcatel Alsthom Recherche, 91 - Marcoussis (France)

    1996-12-31

    The lithium carbon batteries studied in this paper use plasticized polymer electrolytes made with passive polymer matrix swollen by a liquid electrolyte with a high ionic conductivity (> 10{sup -3} S/cm at 25 deg. C). The polymers used to prepare the gels are polyacrylonitrile (PAN) and vinylidene poly-fluoride (PVdF). The electrochemical and physical properties of these materials are analyzed according to their composition. The behaviour of solid electrolytes with different materials of lithium ion insertion (graphite and LiNiO{sub 2}) are studied and compared to liquid electrolytes. The parameters taken into account are the reversible and irreversible capacities, the cycling performance and the admissible current densities. Finally, complete lithium ion batteries with gelled electrolytes were manufactured and tested. (J.S.) 2 refs.

  19. Preparation and Characterization of An Alkaline Solid PVA-PC-KOH-H20 Electrolyte%PVA-PC-KOH-H20碱性固体聚合物电解质的制备和表征

    Institute of Scientific and Technical Information of China (English)

    李月丽; 刘建; 王松林; 张金标

    2012-01-01

    以PVA—KOH—H20体系碱性固体聚合物电解质为基质,添加适量碳酸丙烯酯(PC)做增塑剂来提高性能。利用X一射线衍射分析、红外光谱技术分析、交流阻抗谱和循环伏安法等对样品进行了表征。研究结果表明,聚合物电解质以无定形态为主,含极少量晶相,PC的适量添加可以降低电解质膜的结晶度增大无定形区域,从而提高室温离子电导率,当PVA:PC=3:I(质量比)复合电解质膜的室温电导率最高可达4.41x10-2S/cm,同时电化学稳定窗口也满足使用要求(相对于不锈钢电极,其电压稳定窗口为3.5v)。%A composite alkaline solid polymer electrolyte(ASPE) based on PVA-KOH-H20 were prepared using polyearbonate (PC) as plasficizem. The properties of PVA based composite alkaline polymer electrolytes were studied by X-ray diffraction (XRD), Infrared spectroscopy analysis (IR),cyelie voltammetry and AC impedanee methods. The experimental results indicated that ASPE films showed anamorphous phase with farthing crystal phase, the addition of PC redueed the crystallinity of ASPE to make amorphous region augmented. The ionic eonductivity of the electrolyte was improved with the content of PC inereased appropriately, the electrolyte's ionic conductivity is up to a maximum(4.41xl0-2 S/em)when the weight ratio PVA/PC is equal to 3, and the electrochemical potential stability window was 3.5V for SS/ASPE/SS ( SS for stainless steel) that can meet the ecmioment' demands for their electrolytes.

  20. Platinum nanoparticles on carbon-nanotube support prepared by room-temperature reduction with H2 in ethylene glycol/water mixed solvent as catalysts for polymer electrolyte membrane fuel cells

    Science.gov (United States)

    Zheng, Yuying; Dou, Zhengjie; Fang, Yanxiong; Li, Muwu; Wu, Xin; Zeng, Jianhuang; Hou, Zhaohui; Liao, Shijun

    2016-02-01

    Polyol approach is commonly used in synthesizing Pt nanoparticles in polymer electrolyte membrane fuel cells. However, the application of this process consumes a great deal of time and energy, as the reduction of precursors requires elevated temperatures and several hours. Moreover, the ethylene glycol and its oxidizing products bound to Pt are difficult to remove. In this work, we utilize the advantages of ethylene glycol and prepare Pt nanoparticles through a room-temperature hydrogen gas reduction in an ethylene glycol/water mixed solvent, which is followed by subsequent harvesting by carbon nanotubes as electrocatalysts. This method is simple, facile, and time-efficient, as the entire room-temperature reduction process is completed in a few minutes. As the solvent changes from water to an ethylene glycol/water mix, the size of Pt nanoparticles varies from 10 to 3 nm and their shape transitions from polyhedral to spherical. Pt nanoparticles prepared in a 1:1 volume ratio mixture of ethylene glycol/water are uniformly dispersed with an average size of ∼3 nm. The optimized carbon nanotube-supported Pt electrocatalyst exhibits excellent methanol oxidation and oxygen reduction activities. This work demonstrates the potential use of mixed solvents as an approach in materials synthesis.

  1. Electrical Properties of NASICON-type Structured Li1.3Al0.3Ti1.7(PO4)3 Solid Electrolyte Prepared by 1,2-Propylene glycol-assisted Sol-gel Method

    Institute of Scientific and Technical Information of China (English)

    Lin-chao Zhang; Peng Chen; Zhang Hu; Chun-hua Chen

    2012-01-01

    Lithium-ion conductor Li1.3Al0.3Ti1.7(PO4)3 with an ultrapure NASICON-type phase is synthesized by a 1,2-propylene glycol (1,2-PG)-assisted sol-gel method and characterized by differential thermal analysis-thermo gravimetric analysis,X-ray diffraction,scanning electron microscopy,electrochemical impedance spectroscopy,and chronoamperometry test.Due to the use of 1,2-PG,a homogeneous and light yellow transparent precursor solution is obtained without the precipitation of Ti4+ and Al3+ with PO43-.Well crystallized Li1.3Al0.aTi1.7(PO4)3 can be prepared at much lower temperatures from 850 ℃ to 950 ℃ within a shorter synthesis time compared with that prepared at a temperature above 1000 ℃ by a conventional solid-state reaction method.The lithium ionic conductivity of the sintered pellets is up to 0.3 mS/cm at 50 ℃ with an activation energy as low as 36.6 kJ/mol for the specimen pre-sintered at 700 ℃ and sintered at 850 ℃.The high conductivity,good chemical stability and easy fabrication of the Li1.3Al0.3Ti1.7(PO4)3 provide a promising candidate as solid electrolyte for all-solid-state Li-ion rechargeable batteries.

  2. Modelling dense relational data

    DEFF Research Database (Denmark)

    Herlau, Tue; Mørup, Morten; Schmidt, Mikkel Nørgaard;

    2012-01-01

    Relational modelling classically consider sparse and discrete data. Measures of influence computed pairwise between temporal sources naturally give rise to dense continuous-valued matrices, for instance p-values from Granger causality. Due to asymmetry or lack of positive definiteness they are no......Relational modelling classically consider sparse and discrete data. Measures of influence computed pairwise between temporal sources naturally give rise to dense continuous-valued matrices, for instance p-values from Granger causality. Due to asymmetry or lack of positive definiteness...... they are not naturally suited for kernel K-means. We propose a generative Bayesian model for dense matrices which generalize kernel K-means to consider off-diagonal interactions in matrices of interactions, and demonstrate its ability to detect structure on both artificial data and two real data sets....

  3. Highly-dispersed Ta-oxide catalysts prepared by electrodeposition in a non-aqueous plating bath for polymer electrolyte fuel cell cathodes

    KAUST Repository

    Seo, Jeongsuk

    2012-01-01

    The Ta-oxide cathode catalysts were prepared by electrodeposition in a non-aqueous solution. These catalysts showed excellent catalytic activity and have an onset potential of 0.92 V RHE for the oxygen reduction reaction (ORR). The highly-dispersed Ta species at the nanometer scale on the carbon black was an important contributor to the high activity. © 2012 The Royal Society of Chemistry.

  4. A hard-template method for the preparation of IrO(2) , and its performance in a solid-polymer-electrolyte water electrolyzer.

    Science.gov (United States)

    Li, Guangfu; Yu, Hongmei; Song, Wei; Dou, Meiling; Li, Yongkun; Shao, Zhigang; Yi, Baolian

    2012-05-01

    Morphological control by SBA-15: The performance of catalysts for the oxygen evolution reaction (OER) depends strongly on their structural and morphological properties. An IrO(2) nanomaterial with a morphology suitable for the OER is prepared by using a synthetic scheme involving a zeolite template, and shows enhanced activity and stability compared to IrO(2) fabricated by the traditional Adams-fusion method.

  5. TEM analysis and wear resistance of the ceramic coatings on Q235 steel prepared by hybrid method of hot-dipping aluminum and plasma electrolytic oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Lu Lihong [State Key Laboratory of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao 066004 (China); Science and Research Department, Chinese People' s Armed Police Academy, Langfang 065000 (China); Zhang Jingwu [State Key Laboratory of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao 066004 (China); Shen Dejiu, E-mail: sdj217@ysu.edu.cn [State Key Laboratory of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao 066004 (China); Wu Lailei; Jiang Guirong [State Key Laboratory of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao 066004 (China); Li Liang [State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084 (China)

    2012-01-25

    Highlights: Black-Right-Pointing-Pointer Transmission electron microscopy (TEM) was firstly used to analyze the phase composition of the ceramic coatings. Black-Right-Pointing-Pointer The phase composition of the ceramic coatings is mainly amorphous phase and crystal Al{sub 2}O{sub 3} oxides. Black-Right-Pointing-Pointer The cross-section micro-hardness of the treated samples was investigated, the hardness of the ceramic coatings is about HV1300. Black-Right-Pointing-Pointer The wear resistance of the PEO samples is about 3 times higher than that of the heat treated 45 steel. - Abstract: The hybrid method of PEO and hot-dipping aluminum (HDA) was employed to deposit composite ceramic coatings on the surface of Q235 steel. The composition of the composite coatings was investigated with X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The cross-section microstructure and micro-hardness of the treated specimens were investigated and analyzed with scanning electron microscopy (SEM) and microscopic hardness meter (MHM), respectively. The wear resistance of the ceramic coatings was investigated by a self-made rubbing wear testing machine. The results indicate that metallurgical bonding can be observed between the ceramic coatings and the steel substrate. There are many micro-pores and micro-cracks, which act as the discharge channels and result of quick and non-uniform cooling of melted sections in the plasma electrolytic oxidation ceramic coatings. The phase composition of the ceramic coatings is mainly composed of amorphous phase and crystal Al{sub 2}O{sub 3} oxides. The crystal Al{sub 2}O{sub 3} phase includes {kappa}-Al{sub 2}O{sub 3}, {theta}-Al{sub 2}O{sub 3} and {beta}-Al{sub 2}O{sub 3}. The grain size of the {kappa}-Al{sub 2}O{sub 3} crystal is quite non-uniform. The hardness of the ceramic coatings is about HV1300 and 10 times higher than that of the Q235 substrate, which was favorable to the better wear resistance of the ceramic

  6. Plasma electrolytic oxidation coating of synthetic Al-Mg binary alloys

    Energy Technology Data Exchange (ETDEWEB)

    Tarakci, Mehmet, E-mail: mtarakci@gyte.edu.tr

    2011-12-15

    The binary Al-Mg synthetic alloys were prepared in a vacuum/atmosphere controlled furnace with the addition of 0.5, 1, 2, 4, 7, and 15 wt.% pure Mg into pure aluminum as substrate material. The surfaces of the Al-Mg alloys and pure aluminum were coated for 120 min by plasma electrolytic oxidation in the same electrolyte of 12 g/L sodium silicate and 2 g/L KOH in distilled water. The coating was characterized by X-ray diffraction, scanning electron microscopy, profilometry and Vickers microhardness measurements. There regions of loose outer layer, dense inner layer with precipitate like particles of {alpha}-Al{sub 2}O{sub 3} and a thin transition layer were identified for the coated samples. The coating thickness increases from 85 to 150 {mu}m with Mg contents in the alloys. The surface morphology becomes more porous and consequently surface roughness tends to increase with plasma electrolytic oxidation treatment and further with Mg content. The increase in magnesium content reduces the formation of {alpha}-Al{sub 2}O{sub 3} and crystalline mullite phases in the coating and decreases microhardness of coating. The Mg concentration is constant throughout the other loose and dense regions of coating though it gradually decreases in the thin inner region. - Research Highlights: Black-Right-Pointing-Pointer The average thickness of PEO coating of Al-Mg alloys increases with Mg content. Black-Right-Pointing-Pointer The addition of Mg reduces and prevents the formation of {alpha}-Al{sub 2}O{sub 3} and mullite. Black-Right-Pointing-Pointer The surface roughness increases with Mg content in the Al-Mg alloys. Black-Right-Pointing-Pointer The hardness values of the coating decreases with the Mg amount in the substrate. Black-Right-Pointing-Pointer The Mg concentration is constant throughout the main regions of coating.

  7. Preparation of 15 mol% YO 1.5-doped ThO 2 disk electrolytes by a polymeric gel-combustion method

    Science.gov (United States)

    Arul Antony, S.; Nagaraja, K. S.; Sreedharan, O. M.

    2001-06-01

    A hybrid of polymeric gel and auto-combustion techniques was adapted for the synthesis and lower temperature sintering of 15 mol% YO 1.5-doped thoria (15 YDT) homogeneous solid solutions at 1350°C. The YDT discs so prepared were of density better than 99% theoretical and the cubic cell parameter was ao=558.15(±0.13) pm in close agreement with 557.8 pm recently reported as high quality data in JCPDS confirming the validity of the anion vacancy model for Th 0.85Y 0.15O 1.925.

  8. TEMPO addition into pre-irradiated fluoropolymers and living-radical graft polymerization of styrene for preparation of polymer electrolyte membranes

    Energy Technology Data Exchange (ETDEWEB)

    Sawada, Shin-ichi, E-mail: sawada.shinnichi@jaea.go.j [Conducting Polymer Materials Research Group, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Department of Nuclear Engineering and Management, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Suzuki, Akihiro; Terai, Takayuki [Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Maekawa, Yasunari, E-mail: maekawa.yasunari@jaea.go.j [Conducting Polymer Materials Research Group, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2010-04-15

    We prepared proton exchange membranes (PEMs) by 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO)-mediated living-radical graft polymerization (LRGP) of styrene into fluoropolymer films and subsequent sulfonation. Poly(vinylidene fluoride) (PVDF) and poly(ethylene-co-tetrafluoroethylene) (ETFE) films were first irradiated and then treated with TEMPO solutions in various solvents. TEMPO addition was confirmed by the test of styrene grafting into TEMPO-treated films at 60 deg. C, at which the LRGP never proceeds. This test enabled us to differentiate the LRGP from the conventional graft polymerization. In order to gain a deep insight about TEMPO-addition reaction, the TEMPO-penetration behavior into the base polymer films was examined by a permeation experiment and computer simulation. Xylene and dioxane were appropriate solvents for the complete introduction of TEMPO into PVDF and ETFE films, respectively. Then, the LRGP of styrene was performed based on the fully TEMPO-capped films at 125 deg. C with various solvents. By using an alcoholic solvent, the degree of grafting was enhanced and it reached a maximum of 38%. This grafted film was sulfonated to prepare a PEM showing an ion exchange capacity of 2.2 meq/g and proton conductivity of 1.6x10{sup -1} S/cm.

  9. Densely crosslinked polycarbosiloxanes .2. Thermal and mechanical properties

    NARCIS (Netherlands)

    Flipsen, T.A C; Derks, R.; van der Vegt, H.A.; Stenekes, R.; Pennings, A.J; Hadziioannou, G

    1997-01-01

    The thermal and mechanical properties of two densely crosslinked polycarbosiloxane systems were investigated in relation to the molecular structure. The networks were prepared from functional branched prepolymers and crosslinked via a hydrosilylation curing reaction. The prepolymers having only viny

  10. Preparation of low-platinum-content platinum-nickel, platinum-cobalt binary alloy and platinum-nickel-cobalt ternary alloy catalysts for oxygen reduction reaction in polymer electrolyte fuel cells

    Science.gov (United States)

    Li, Mu; Lei, Yanhua; Sheng, Nan; Ohtsuka, Toshiaki

    2015-10-01

    A series of low-platinum-content platinum-nickel (Pt-Ni), platinum-cobalt (Pt-Co) binary alloys and platinum-nickel-cobalt (Pt-Ni-Co) ternary alloys electrocatalysts were successfully prepared by a three-step process based on electrodeposition technique and studied as electrocatalysts for oxygen reduction reaction (ORR) in polymer-electrolyte fuel cells. Kinetics of ORR was studied in 0.5 M H2SO4 solution on the Pt-Ni, Pt-Co and Pt-Ni-Co alloys catalysts using rotating disk electrode technique. Both the series of Pt-Ni, Pt-Co binary alloys and the Pt-Ni-Co ternary alloys catalysts exhibited an obvious enhancement of ORR activity in comparison with pure Pt. The significant promotion of ORR activities of Pt-Ni and Pt-Co binary alloys was attributed to the enhancement of the first electron-transfer step, whereas, Pt-Ni-Co ternary alloys presented a more complicated mechanism during the electrocatalysis process but a much more efficient ORR activities than the binary alloys.

  11. Preparation and characterization of Nafion - TiO{sub 2} composite electrolytes for application in proton exchange membrane fuel cells; Preparacao e caracterizacao de eletrolitos compositos Nafion - TiO{sub 2} para aplicacao em celulas a combustivel de membrana de troca protonica

    Energy Technology Data Exchange (ETDEWEB)

    Matos, Bruno Ribeiro de

    2008-11-06

    The fabrication and characterization of Nafion - TiO{sub 2} composites, and the use of such electrolytes in PEM (Proton Exchange Membrane) fuel cell operating at high temperature (130 deg C) were studied. The operation of a PEM fuel cell at such high temperature is considered as an effective way to promote fast electrode reaction kinetics, high diffusional transport, and high tolerance to the carbon monoxide fuel contaminant. The polymer Nafion{sup R} is the most used electrolyte in PEM fuel cells due to its high proton conductivity. However, the proton transport in Nafion is dependent on the water content in the polymeric membrane. The need of absorbed water in the polymer structure limits the operation of the fuel cell to temperatures close to 100 deg C, above which Nafion exhibits a fast decrease of the ionic conductivity. In order to increase the performance of the electrolyte operating at high temperatures, Nafion-TiO{sub 2} composites have been prepared by casting. The addition of titania hygroscopic particles to the polymeric matrix aims at the enhancement of the humidification of the electrolyte at temperatures above 100 deg C. Three types of titania particles with different specific surface area and morphology have been investigated. Nafion-based composites with the addition of titania nanoparticles, in the 2.5-15 wt.% range, with nearly spherical shape and specific surface area up to approx. 115 m{sup 2}g{sup -1} were found to have higher glass transition temperature than the polymer. Such an increase improves the stability of the electrolyte during the fuel cell operation at high temperatures. The addition of titania-derived nanotubes results in a pronounced increase of the performance of PEM fuel cell operating at 130 deg C. In this composite, the high specific surface area and the tubular shape of the inorganic phase are responsible for the measured increase of both the absorption and retention of water of the composite electrolyte. Nonetheless, the

  12. The influence of nanoparticle aggregation on formation of ZrO{sub 2} electrolyte thin films by electrophoretic deposition

    Energy Technology Data Exchange (ETDEWEB)

    Kalinina, E.G., E-mail: kalinina@iep.uran.ru [Institute of Electrophysics, Russian Academy of Sciences, Ural Branch, 106 Amundsen Street, 620016 Ekaterinburg (Russian Federation); Ural Federal University, 19 Mira Street, 620002 Ekaterinburg (Russian Federation); Efimov, A.A. [Moscow Institute of Physics and Technology, 9 Institutskii per., 141700 Dolgoprudny, Moscow Region (Russian Federation); Safronov, A.P. [Institute of Electrophysics, Russian Academy of Sciences, Ural Branch, 106 Amundsen Street, 620016 Ekaterinburg (Russian Federation); Ural Federal University, 19 Mira Street, 620002 Ekaterinburg (Russian Federation)

    2016-08-01

    The paper presents the results of the studies of electrically stabilized nonaqueous suspensions of ZrO{sub 2} stabilized by Y{sub 2}O{sub 3} (YSZ) nanoparticles with an average diameter of 11 nm for the formation of green films of electrolyte for solid oxide fuel cells. Nanoparticles were de-aggregated to different degrees, which were provided by the ultrasonic treatment and the centrifugation, and monitored by the dynamic light scattering. YSZ green thin films were obtained by the electrophoretic deposition (EPD) on dense lanthanum strontium manganite cathodes using suspensions with the average diameter of aggregates: 107; 66; 53 nm. To investigate the possibilities of EPD we used the model drying of the same suspensions cast upon the same substrates. It was shown that the structure and the morphology of the green films obtained by EPD was different compared to the films prepared by the model drying of the suspension. The drying of the stable suspension resulted in the formation of loose aggregates on the surface. The efficient packing of electrically stabilized particles was prevented by the forces of electrostatic repulsion between them. In the case of EPD the electrocoagulation of particles near the cathode takes place with the formation of dense aggregates. As a result, uncharged spherical aggregates with an average size of about 100–200 nm settle on the surface of the cathode and pack into a uniform dense coating suitable for the subsequent sintering of a gas-tight coating for the solid YSZ electrolyte. - Highlights: • Impact of nanoparticle aggregation on the electrophoretic deposition is studied. • Sedimentation of stabilized particles results in formation of loose aggregates. • The formation of dense layer is facilitated by electrocoagulation of particles.

  13. Towards Prognostics of Electrolytic Capacitors

    Data.gov (United States)

    National Aeronautics and Space Administration — A remaining useful life prediction algorithm and degradation model for electrolytic capacitors is presented. Electrolytic capacitors are used in several applications...

  14. Dense Plasma Focus Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hui [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Li, Shengtai [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jungman, Gerard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hayes-Sterbenz, Anna Catherine [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-31

    The mechanisms for pinch formation in Dense Plasma Focus (DPF) devices, with the generation of high-energy ions beams and subsequent neutron production over a relatively short distance, are not fully understood. Here we report on high-fidelity 2D and 3D numerical magnetohydrodynamic (MHD) simulations using the LA-COMPASS code to study the pinch formation dynamics and its associated instabilities and neutron production.

  15. Preparation and electrochemical properties of SrCe0.4Zr0.4Yb0.2O2.9 electrolyte

    Indian Academy of Sciences (India)

    Juan Li; Ruisong Guo; Hong Jiang

    2012-11-01

    The perovskite Yb-doped strontium cerate–zirconate material, SrCe0.4Zr0.4Yb0.2O2.9, was prepared by solid-state reaction and the structure was characterized by X-ray diffraction. The calcination process of the powder was investigated by thermogravimetric/differential thermal analysis (TG–DTA). The high temperature conductivities were measured by d.c. four-probe technique in the temperature range from 500 to 950°C in wet hydrogen and effect of temperature on conductivity was investigated. The conductivity increased with the elevation of temperature from 500 to 950°C. The highest conductivity of 4.4 × 10-2 S.cm-1 was observed for SrCe0.4Zr0.4Yb0.2O2.9 at 950°C. The current–voltage (–) and current–power (–) characteristics of the single cell (H2, Pt/SrCe0.4Zr0.4Yb0.2O2.9/Pt, O2) at temperature range from 600 to 850°C were tested. With the temperature increasing from 600 to 850°C, the open circuit voltage (OCV) decreased from 1.164 to 1.073 V and the ionic transfer number decreased from 0.996 to 0.946. At 850°C, the maximum power density of 25.2 mW.cm-2 was observed.

  16. Electrode and solid electrolyte thin films for secondary lithium-ion batteries

    Science.gov (United States)

    Chen, C. H.; Kelder, E. M.; Schoonman, J.

    Electrostatic spray deposition (ESD) was employed to prepare thin layers of Li 1.2Mn 2O 4 (nominal composition) and BPO 4:0.035Li 2O for all-solid-state thin film lithium-ion batteries. The relationships between layer morphologies and deposition conditions such as solvent composition of the precursor solutions and substrate temperature were investigated. It was found that a low substrate temperature and/or high boiling point of the solvent may lead to a relatively dense structure. Reticular porous structures are formed, if films were deposited at 250°C and a mixture of 85 vol.% butyl carbitol and 15 vol.% ethanol was used as the solvent. The Li 1.2Mn 2O 4 layers, formed in the 250-400°C temperature range, were amorphous or micro-crystalline. After annealing beyond 600 °C, they could be crystallized into a spinel-structured material. Glassy BPO 4:0.035Li 2O layers could fill the pores of porous Li 1.2Mn 2O 4 layers to form a dense intermediate electrolyte layer. Thin-film rocking-chair batteries, Li 1.2Mn 2O 4|BPO 4:0.035Li 2O|Li 1.2Mn 2O 4|Al, were prepared and revealed an open-circuit voltage of about 1.2 V after charging.

  17. Preparation of Sufonated Poly (ethylene-co-tetrafluoroethylene-graft-styrene Based Polymer Electrolyte Membranes for Fuel Cell by using Gamma Irradiation Technique

    Directory of Open Access Journals (Sweden)

    A. Suliwarno

    2012-04-01

    Full Text Available Poly (ethylene-co-tetrafluoroethylene-graft-styrene-sulfonate was successfully prepared by irradiation grafting of a styrene monomer into ethylenetetrafluoro-ethylene (ETFE films and followed by sulfonation of the graft chains. Five film sheets of ETFE which having a size of 3 cm  8 cm, thickness of 25 µm were packed in vacuum using a Y type tube filled with argon gas. The samples were irradiated using γ-rays with a dose of 15 kGy at 15 kGy/h. The iradiated samples were grafted by using styrene monomer at 60o C for 1, 3, 5, 7 and 9 h, respectively. The grafted samples (ETFE-g-St were washed with xylene to remove homopolymer of polystyrene, and then its degree of grafting (DG was determined. Sulfonation was carried out by using 0.2 M chlorosulfonic acid in dichloroethane solution at a water bath of 60oC for 6 h. Sulfonated samples (ETFE-g-St-SO3H were washed with water to neutralize its acidity, and dried in a vacuum drier at 40oC for 15 h. The dried sample was weighed as sulfonated sample in order to determine the degree of sulfonation (%DS. Membrane properties of EFTE-g-St-SO3H sample such as ion exchange capacity (IEC, proton conductivity in cross direction (σ1, and in-plane direction (σ11 were determined by using a HIOKI-3522 LCR HI tester. Durability test of samples were conducted in hot water and 3% H2O2 respectively.. The proton conductivity measurement and durability of the membrane were compared to Nafion 112® as standard. The experimental results showed that the degree of grafting was increased with time of reaction for copolymerization, while %DS gave excellent results with an average of 92.7%. The IEC value was more affected by the %DG as compared to that of %DS effect. The average of σl value of the sample was 0.055 S/cm, compared to σl of Nafion112® that was 0.066 S/cm. The average of ll of the sample was 0.18 S/cm, while the ll of Nafion 112® was = 0.36 S/cm. The sample of SA004 with 53.49% DG was more stable than

  18. Electrolyte for batteries with regenerative solid electrolyte interface

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Jie; Lu, Dongping; Shao, Yuyan; Bennett, Wendy D.; Graff, Gordon L.; Liu, Jun; Zhang, Ji-Guang

    2017-08-01

    An energy storage device comprising: an anode; and a solute-containing electrolyte composition wherein the solute concentration in the electrolyte composition is sufficiently high to form a regenerative solid electrolyte interface layer on a surface of the anode only during charging of the energy storage device, wherein the regenerative layer comprises at least one solute or solvated solute from the electrolyte composition.

  19. Poly-electrolytes for fuel cells: tools and methods for characterization; Polyelectrolytes pour piles a combustible: outils et methodes de caracterisation

    Energy Technology Data Exchange (ETDEWEB)

    Marechal, M.

    2004-12-15

    The research works reported in the manuscript are a contribution to the study of poly-electrolytes for Proton Exchange Membrane Fuel Cells (PEMFC). They are supported by two investigation tools, i.e. the study of model molecules and accurate conductivity measurements. With regard to the material science domain, the optimization of poly-sulfone sulfonation procedure allows chain breaking to be reduced and even eliminated while obtaining reproducible sulfonation degrees. It is thus possible to improve the mechanical properties of the dense membrane elaborated with these poly-electrolytes before performing the tests on the MEA (Membrane Electrode Assembly). In parallel, the functionalization of microporous silicon made it possible to prepare poly-electrolytes reinforced by the mechanical strength of the silicon separator. With regard to the physicochemical and electrochemical characterizations, the model molecules, with the same functions and groups than for associated polymers, make it possible to amplify the electrochemical or thermal phenomena vs. the corresponding polymers. Thus, they simulate an accelerated ageing of the poly-electrolytes. The development of a new conductivity measurement set allows conductivity to be obtained with a great accuracy, in a wide range of temperature and relative humidity. (author)

  20. Electrospun nanocomposite fibrous polymer electrolyte for secondary lithium battery applications

    Science.gov (United States)

    Padmaraj, O.; Rao, B. Nageswara; Jena, Paramananda; Venkateswarlu, M.; Satyanarayana, N.

    2014-04-01

    Hybrid nanocomposite [poly(vinylidene fluoride -co- hexafluoropropylene) (PVdF-co-HFP)/magnesium aluminate (MgAl2O4)] fibrous polymer membranes were prepared by electrospinning method. The prepared pure and nanocomposite fibrous polymer electrolyte membranes were soaked into the liquid electrolyte 1M LiPF6 in EC: DEC (1:1,v/v). XRD and SEM are used to study the structural and morphological studies of nanocomposite electrospun fibrous polymer membranes. The nanocomposite fibrous polymer electrolyte membrane with 5 wt.% of MgAl2O4 exhibits high ionic conductivity of 2.80 × 10-3 S/cm at room temperature. The charge-discharge capacity of Li/LiCoO2 coin cells composed of the newly prepared nanocomposite [(16 wt.%) PVdF-co-HFP+(5 wt.%) MgAl2O4] fibrous polymer electrolyte membrane was also studied and compared with commercial Celgard separator.

  1. Preparation of Lanthanum Nickel Oxide-Coated Ni Sheet Anodes and Their Application to Electrolytic Production of (CF3)3N in (CH3)4NF·4.0HF Melt

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A new process for electrolytic production of a perfluorinated compound, (CF3)3N, using lanthanum nickel oxide-coated Ni sheet anode in the (CH3)4NF·4.0HF melt at room temperature, was developed. Thin films of the lanthanum nickel oxides were prepared on Ni sheets by sol-gel coating method using polyvinlylpyrrolidone(PVP). The main components of the thin films were La2O3, LaNiO3, and La2NiO4 at 500, 750 and 1000 ℃, respectively. The anode performance in the (CH3)4NF·4.0HF melt depends greatly on the main component of the thin film, and the LaNiO3-coated Ni sheet anode gives the best anode performance. The potential of LaNiO3-coated Ni sheet anode remains constant at 5.9 V during electrolysis at 20 mA·cm-2 in the (CH3)4NF·4.0HF melt for 100 h. This is because LaNiO3 and NiF3 and/or Ni2F5, the latter of which was formed during electrolysis, in the film give a high electronic conductivity to the surface film during electrolysis. The maximum mole fraction of (CF3)3N (21.4%) was obtained at 20 mA·cm-2 in (CH3)4NF·4.0HF melt using the LaNiO3-coated Ni sheet.

  2. Preparation and characterization of TiO{sub 2} doped and MgO stabilized Na–β″-Al{sub 2}O{sub 3} electrolyte via a citrate sol–gel method

    Energy Technology Data Exchange (ETDEWEB)

    Shan, Shi-Jie; Yang, Li-Ping; Liu, Xiao-Min; Wei, Xiao-Ling [College of Materials Science and Engineering, Nanjing University of Technology, 5 Xinmofan Road, Nanjing, Jiangsu 210009 (China); Yang, Hui, E-mail: yanghui@njut.edu.cn [College of Materials Science and Engineering, Nanjing University of Technology, 5 Xinmofan Road, Nanjing, Jiangsu 210009 (China); Shen, Xiao-Dong [College of Materials Science and Engineering, Nanjing University of Technology, 5 Xinmofan Road, Nanjing, Jiangsu 210009 (China)

    2013-06-25

    Highlights: ► TiO{sub 2} doped Na–β″-Al{sub 2}O{sub 3} electrolyte is synthesized via a sol–gel method with C{sub 16}H{sub 36}O{sub 4}Ti as the precursor for TiO{sub 2}. ► The optimized sample contains 90.28% of β″ phase and presents a very high relative density (99.5%). ► The optimized sample exhibits the bending strength up to 180 MPa and an ionic conductivity up to 0.21 S cm{sup −1} (350 °C). -- Abstract: TiO{sub 2} doped and MgO stabilized Na–β″-Al{sub 2}O{sub 3} is synthesized via a citrate sol–gel method starting with Al(NO{sub 3}){sub 3}, NaNO{sub 3}, Mg(NO{sub 3}){sub 2} and C{sub 16}H{sub 36}O{sub 4}Ti (tetrabutyl titanate, abbreviated as TBT). It is found that the TBT amount in the starting materials is the key factor to affect the properties of the final product, therefore, the samples sintered from precursors containing different amounts of TBT are systematically investigated by means of powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). Meanwhile, the relative density, mechanical strength and electrical properties of the prepared samples are also measured. The optimized sample contains 90.28% of β″ phase, exhibits a uniform and compact microstructure with a relative density as high as 99.5% of theoretical density (TD). In addition, this sample exhibits a bending strength up to 180 MPa and an ionic conductivity up to 0.21 S cm{sup −1} at 350 °C.

  3. Preparation and Endurance of Electrolyte-Supported Solid Oxide Fuel Cell%电解质支持型固体氧化物燃料电池的制备及其工作稳定性

    Institute of Scientific and Technical Information of China (English)

    刘润茹; 王德军; 冷静

    2014-01-01

    利用固相反应法制备固体氧化物燃料电池(SOFC)的复合阳极材料 NiO-ScSZ 和复合阴极材料(La0.8 Sr0.2)0.98 MnO3(LSM),并对组装的电解质支持型单电池 NiO-ScSZ-LSM进行I-V性能测试,其输出电压每0.2 A为0.9 V.在外加恒定电流密度(0.2 A/cm2)的条件下,利用电化学测试仪测试该电池的总电压为每1000 h衰减0.02 V.电流遮断法解析表明,该单电池电压衰减主要为阴极过电压所致.%Cermet anode material NiO-ScSZ and cathode material (La0.8 Sr0.2 )0.98 MnO3 (LSM)were prepared via solid state reaction method. The performance electrolyte-supported single cell of NiO-ScSZ-LSM exibited an output voltage of 0.9 V at 0.2 A described by current-voltage characterized curve.The investigation on the endurance of the single cell indicates that the whole voltage decay is 0.02 V per 1 000 h (at a current density of 0.2 A/cm2 )by electro-chemical measurement.The main resource of it comes from cathodic over-voltage by galvanic current interruption method.

  4. Electrolytic oxidation of anthracite

    Science.gov (United States)

    Senftle, F.E.; Patton, K.M.; Heard, I.

    1981-01-01

    An anthracite slurry can be oxidized only with difficulty by electrolytic methods in which aqueous electrolytes are used if the slurry is confined to the region of the anode by a porous pot or diaphragm. However, it can be easily oxidized if the anthracite itself is used as the anode. No porous pot or diaphragm is needed. Oxidative consumption of the coal to alkali-soluble compounds is found to proceed preferentially at the edges of the aromatic planes. An oxidation model is proposed in which the chief oxidants are molecular and radical species formed by the electrolytic decomposition of water at the coal surface-electrolyte interface. The oxidation reactions proposed account for the opening of the aromatic rings and the subsequent formation of carboxylic acids. The model also explains the observed anisotropic oxidation and the need for the porous pot or diaphragm used in previous studies of the oxidation of coal slurries. ?? 1981.

  5. Solid electrolytic fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Masayasu; Yamauchi, Yasuhiro; Kamisaka, Mitsuo; Notomi, Kei.

    1989-04-21

    Concerning a solid electrolytic fuel cell with a gas permeable substrate pipe, a fuel electrode installed on this substrate pipe and an air electrode which is laminated on this fuel electrode with the electrolyte in between, the existing fuel cell of this kind uses crystals of CaMnO3, etc. for the material of the air electrode, but its electric resistance is big and in order to avert this, it is necessary to make the film thickness of the air electrode big. However, in such a case, the entry of the air into its inside worsens and the cell performance cannot develop satisfactorily. In view of the above, in order to obtain a high performance solid electrolytic fuel cell which can improve electric conductivity without damaging diffusion rate of the air, this invention proposes with regard to the aforementioned solid electrolytic fuel cell to install a heat resistant and conductive member inside the above air electrode. 6 figs.

  6. Polymer electrolyte reviews. 1

    Energy Technology Data Exchange (ETDEWEB)

    Mac Callum, J.R.; Vincent, C.A.

    1987-01-01

    The development of polymer electrolytes which have potential applications in battery technology has resulted in an escalation of research into the synthesis of new macromolecular supports and the mechanisms of ionic transport within the solid matrix. Investigation of the properties of polymer electrolytes has brought together polymer chemists and electrochemists, and the understanding of the solubility and transport of electrolytes in organic polymers is now developing from this pooled experience. This book deals with experimental, theoretical and applied aspects of solid solutions of electrolytes used in coordinating polymer matrices. Attention is focused on the synthesis and properties of these new materials, the mechanisms of conduction processes and practical applications, especially with regard to battery technology.

  7. Warm dense crystallography

    Science.gov (United States)

    Valenza, Ryan A.; Seidler, Gerald T.

    2016-03-01

    The intense femtosecond-scale pulses from x-ray free electron lasers (XFELs) are able to create and interrogate interesting states of matter characterized by long-lived nonequilibrium semicore or core electron occupancies or by the heating of dense phases via the relaxation cascade initiated by the photoelectric effect. We address here the latter case of "warm dense matter" (WDM) and investigate the observable consequences of x-ray heating of the electronic degrees of freedom in crystalline systems. We report temperature-dependent density functional theory calculations for the x-ray diffraction from crystalline LiF, graphite, diamond, and Be. We find testable, strong signatures of condensed-phase effects that emphasize the importance of wide-angle scattering to study nonequilibrium states. These results also suggest that the reorganization of the valence electron density at eV-scale temperatures presents a confounding factor to achieving atomic resolution in macromolecular serial femtosecond crystallography (SFX) studies at XFELs, as performed under the "diffract before destroy" paradigm.

  8. Dense Suspension Splash

    Science.gov (United States)

    Zhang, Wendy; Dodge, Kevin M.; Peters, Ivo R.; Ellowitz, Jake; Klein Schaarsberg, Martin H.; Jaeger, Heinrich M.

    2014-03-01

    Upon impact onto a solid surface at several meters-per-second, a dense suspension plug splashes by ejecting liquid-coated particles. We study the mechanism for splash formation using experiments and a numerical model. In the model, the dense suspension is idealized as a collection of cohesionless, rigid grains with finite surface roughness. The grains also experience lubrication drag as they approach, collide inelastically and rebound away from each other. Simulations using this model reproduce the measured momentum distribution of ejected particles. They also provide direct evidence supporting the conclusion from earlier experiments that inelastic collisions, rather than viscous drag, dominate when the suspension contains macroscopic particles immersed in a low-viscosity solvent such as water. Finally, the simulations reveal two distinct routes for splash formation: a particle can be ejected by a single high momentum-change collision. More surprisingly, a succession of small momentum-change collisions can accumulate to eject a particle outwards. Supported by NSF through its MRSEC program (DMR-0820054) and fluid dynamics program (CBET-1336489).

  9. Dense Axion Stars

    CERN Document Server

    Braaten, Eric; Zhang, Hong

    2015-01-01

    If the dark matter consists of axions, gravity can cause them to coalesce into axion stars, which are stable gravitationally bound Bose-Einstein condensates of axions. In the previously known axion stars, gravity and the attractive force between pairs of axions are balanced by the kinetic pressure.If the axion mass energy is $mc^2= 10^{-4}$ eV, these dilute axion stars have a maximum mass of about $10^{-14} M_\\odot$. We point out that there are also dense axion stars in which gravity is balanced by the mean-field pressure of the axion condensate. We study axion stars using the leading term in a systematically improvable approximation to the effective potential of the nonrelativistic effective field theory for axions. Using the Thomas-Fermi approximation in which the kinetic pressure is neglected, we find a sequence of new branches of axion stars in which gravity is balanced by the mean-field interaction energy of the axion condensate. If $mc^2 = 10^{-4}$ eV, the first branch of these dense axion stars has mas...

  10. Dense Axion Stars

    Science.gov (United States)

    Braaten, Eric; Mohapatra, Abhishek; Zhang, Hong

    2016-09-01

    If the dark matter particles are axions, gravity can cause them to coalesce into axion stars, which are stable gravitationally bound systems of axions. In the previously known solutions for axion stars, gravity and the attractive force between pairs of axions are balanced by the kinetic pressure. The mass of these dilute axion stars cannot exceed a critical mass, which is about 10-14M⊙ if the axion mass is 10-4 eV . We study axion stars using a simple approximation to the effective potential of the nonrelativistic effective field theory for axions. We find a new branch of dense axion stars in which gravity is balanced by the mean-field pressure of the axion Bose-Einstein condensate. The mass on this branch ranges from about 10-20M⊙ to about M⊙ . If a dilute axion star with the critical mass accretes additional axions and collapses, it could produce a bosenova, leaving a dense axion star as the remnant.

  11. Dense Axion Stars

    Science.gov (United States)

    Mohapatra, Abhishek; Braaten, Eric; Zhang, Hong

    2016-03-01

    If the dark matter consists of axions, gravity can cause them to coalesce into axion stars, which are stable gravitationally bound Bose-Einstein condensates of axions. In the previously known axion stars, gravity and the attractive force between pairs of axions are balanced by the kinetic pressure. If the axion mass energy is mc2 =10-4 eV, these dilute axion stars have a maximum mass of about 10-14M⊙ . We point out that there are also dense axion stars in which gravity is balanced by the mean-field pressure of the axion condensate. We study axion stars using the leading term in a systematically improvable approximation to the effective potential of the nonrelativistic effective field theory for axions. Using the Thomas-Fermi approximation in which the kinetic pressure is neglected, we find a sequence of new branches of axion stars in which gravity is balanced by the mean-field interaction energy of the axion condensate. If mc2 =10-4 4 eV, the first branch of these dense axion stars has mass ranging from about 10-11M⊙ toabout M⊙.

  12. DENSE MEDIUM CYCLONE OPTIMIZATON

    Energy Technology Data Exchange (ETDEWEB)

    Gerald H. Luttrell; Chris J. Barbee; Peter J. Bethell; Chris J. Wood

    2005-06-30

    Dense medium cyclones (DMCs) are known to be efficient, high-tonnage devices suitable for upgrading particles in the 50 to 0.5 mm size range. This versatile separator, which uses centrifugal forces to enhance the separation of fine particles that cannot be upgraded in static dense medium separators, can be found in most modern coal plants and in a variety of mineral plants treating iron ore, dolomite, diamonds, potash and lead-zinc ores. Due to the high tonnage, a small increase in DMC efficiency can have a large impact on plant profitability. Unfortunately, the knowledge base required to properly design and operate DMCs has been seriously eroded during the past several decades. In an attempt to correct this problem, a set of engineering tools have been developed to allow producers to improve the efficiency of their DMC circuits. These tools include (1) low-cost density tracers that can be used by plant operators to rapidly assess DMC performance, (2) mathematical process models that can be used to predict the influence of changes in operating and design variables on DMC performance, and (3) an expert advisor system that provides plant operators with a user-friendly interface for evaluating, optimizing and trouble-shooting DMC circuits. The field data required to develop these tools was collected by conducting detailed sampling and evaluation programs at several industrial plant sites. These data were used to demonstrate the technical, economic and environmental benefits that can be realized through the application of these engineering tools.

  13. Hyperons in dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Dapo, Haris

    2009-01-28

    The hyperon-nucleon YN low momentum effective interaction (V{sub low} {sub k}) allows for an extensive study of the behavior of hyperons in dense matter, together with an investigation of effects of the presence of hyperons on dense matter. The first step towards this goal is the construction of the matrix elements for the hyperon-nucleon low momentum potential. In order to assess the different properties of hyperons within these potentials we calculate the hyperon single-particle potentials in the Hartree-Fock approximation for all of the interactions. Their dependence on both momentum and density, is studied. The single-particle potentials are then used to determine the chemical potential of hyperons in neutron stars. For nucleonic properties, the nucleon-nucleon V{sub low} {sub k} can be used with the caveat that the calculation of the ground-state energy of symmetric nuclear matter does not correctly reproduce the properties of matter at saturation. With the nucleon-nucleon V{sub low} {sub k} one is unable to reach the densities needed for the calculation of neutron star masses. To circumvent this problem we use two approaches: in the first one, we parametrize the entire nucleonic sector. In the second one, we replace only the three-body force. The former will enable us to study neutron star masses, and the latter for studying the medium's response to the external probe. In this thesis we take the external probe to be the neutrino. By combining this parametrization with the YN V{sub low} {sub k} potential, we calculate the equation of state of equilibrated matter. Performing the calculation in the Hartree-Fock approximation at zero temperature, the concentrations of all particles are calculated. From these we can ascertain at which densities hyperons appear for a wide range of parameters. Finally, we calculate the masses of neutron stars with these concentrations. For the calculation of the medium's response to an external probe, we replace the three

  14. Electrochemical Behavior of Steel Bar in Electrolytes:Influence ofpH Value and Cations

    Institute of Scientific and Technical Information of China (English)

    PU Qi; JIANG Linhua; CHU Hongqiang; XU Jinxia; XU Yi

    2011-01-01

    Steel bar corrosion on electrolytes and the influence of cation were investigated.Three electrolytes of Ca(OH)2,NaOH and KOH with pH levels of 12.5,11.5,10.5,9.5,8.5 were prepared,meanwhile,the methods of free corrosion potential and electrochemical impedance spectra (EIS) were used to evaluate the influence of cations on the depassivation of the steel bar in electrolytes.The experimental results indicate that the initial corrosion pH value of the steel bar is influenced by the cation in electrolyte and the influence ofK+ in electrolyte is the most remarkable,followed by Na+ and Ca2+.The initial corrosion pH values are 10.5 in KOH electrolyte,9.5 in NaOH electrolyte and lower than 8.5 in Ca(OH)2 electrolyte.

  15. A Green Method for Processing Polymers using Dense Gas Technology

    Directory of Open Access Journals (Sweden)

    Roshan B. Yoganathan

    2010-05-01

    Full Text Available Dense CO2 can be used as an environmentally-benign polymer processing medium because of its liquid-like densities and gas-like mass transfer properties.In this work, polymer bio-blends of polycarbonate (PC, a biocompatible polymer, and polycaprolactone (PCL, a biodegradable polymer were prepared. Dense CO2 was used as a reaction medium for the melt-phase PC polymerization in the presence of dense CO2-swollen PCL particles and this method was used to prepare porous PC/PCL blends. To extend the applicability of dense CO2 to the biomedical industry and polymer blend processing, the impregnation of ibuprofen into the blend was conducted and subsequent dissolution characteristics were observed.

  16. Effects of fabrication conditions on mechanical properties and microstructure of duplex β″-Al{sub 2}O{sub 3} solid electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Canfield, Nathan L. [Energy Processes & Materials Division, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Kim, Jin Y., E-mail: Jin.Kim@pnnl.gov [Energy Processes & Materials Division, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Bonnett, Jeff F.; Pearson, R.L.; Sprenkle, Vincent L. [Energy Processes & Materials Division, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Jung, Keeyoung [Energy Storage Materials Research Center, Research Institute of Industrial Science and Technology (RIST), Pohang (Korea, Republic of)

    2015-07-15

    Highlights: • The concept of duplex BASEs is presented as a method to lower the ASR for NBBs. • Duplex BASEs consist of thin dense electrolyte and porous support. • Strength of converted BASEs shows a different trend from as-sintered samples. • Cell orientation gives significant impact on strength of duplex BASEs. - Abstract: Na-beta batteries are an attractive technology as a large-scale electrical energy storage for grid applications. However, additional improvements in performance and cost are needed for wide market penetration. To improve cell performance by minimizing polarizations, reduction of electrolyte thickness was attempted using a duplex structure consisting of a thin dense electrolyte layer and a porous support layer. In this paper, the effects of sintering conditions, dense electrolyte thickness, and cell orientation on the flexural strength of duplex BASEs fabricated using a vapor phase approach were investigated. It is shown that sintering at temperatures between 1500 and 1550 °C results in fine grained microstructures and the highest flexural strength after conversion. Increasing thickness of the dense electrolyte has a small impact on flexural strength, while the orientation of load such that the dense electrolyte is in tension instead of compression has major effects on strength for samples with a well-sintered dense electrolyte.

  17. Industrial experiment of copper electrolyte purification by copper arsenite

    Institute of Scientific and Technical Information of China (English)

    ZHENG Ya-jie; XIAO Fa-xin; WANG Yong; LI Chun-hua; XU Wei; JIAN Hong-sheng; MA Yut-ian

    2008-01-01

    Copper electrolyte was purified by copper arsenite that was prepared with As2O3. And electrolysis experiments of purified electrolyte were carried out at 235 and 305 A/m2, respectively. The results show that the yield of copper arsenite is up to 98.64% when the molar ratio of Cu to As is 1.5 in the preparation of copper arsenite. The removal rates of Sb and Bi reach 74.11% and 65.60% respectively after copper arsenite is added in electrolyte. The concentrations of As, Sb and Bi in electrolyte nearly remain constant during electrolysis of 13 d. The appearances of cathode copper obtained at 235 and 305 A/m2 are slippery and even, and the qualification rate is 100% according to the Chinese standard of high-pure cathode copper(GB/T467-97).

  18. Gel electrolytes and electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Fleischmann, Sven; Bunte, Christine; Mikhaylik, Yuriy V.; Viner, Veronika G.

    2017-09-05

    Gel electrolytes, especially gel electrolytes for electrochemical cells, are generally described. In some embodiments, the gel electrolyte layers comprise components a) to c). Component a) may be at least one layer of at least one polymer comprising polymerized units of: a1) at least one monomer containing an ethylenically unsaturated unit and an amido group and a2) at least one crosslinker. Component b) may be at least one conducting salt and component c) may be at least one solvent. Electrodes may comprise the components a), d) and e), wherein component a) may be at least one layer of at least one polymer as described herein. Component d) may be at least one electroactive layer and component e) may be at least one ceramic layer. Furthermore, electrochemical cells comprising component a) which may be at least one layer of at least one polymer as described herein, are also provided.

  19. Perpendicularly Aligned, Anion Conducting Nanochannels in Block Copolymer Electrolyte Films

    Energy Technology Data Exchange (ETDEWEB)

    Arges, Christopher G.; Kambe, Yu; Suh, Hyo Seon; Ocola, Leonidas E.; Nealey, Paul F.

    2016-03-08

    Connecting structure and morphology to bulk transport properties, such as ionic conductivity, in nanostructured polymer electrolyte materials is a difficult proposition because of the challenge to precisely and accurately control order and the orientation of the ionic domains in such polymeric films. In this work, poly(styrene-block-2-vinylpyridine) (PSbP2VP) block copolymers were assembled perpendicularly to a substrate surface over large areas through chemical surface modification at the substrate and utilizing a versatile solvent vapor annealing (SVA) technique. After block copolymer assembly, a novel chemical vapor infiltration reaction (CVIR) technique selectively converted the 2-vinylpyridine block to 2-vinyl n-methylpyridinium (NMP+ X-) groups, which are anion charge carriers. The prepared block copolymer electrolytes maintained their orientation and ordered nanostructure upon the selective introduction of ion moieties into the P2VP block and post ion-exchange to other counterion forms (X- = chloride, hydroxide, etc.). The prepared block copolymer electrolyte films demonstrated high chloride ion conductivities, 45 mS cm(-1) at 20 degrees C in deionized water, the highest chloride ion conductivity for anion conducting polymer electrolyte films. Additionally, straight-line lamellae of block copolymer electrolytes were realized using chemoepitaxy and density multiplication. The devised scheme allowed for precise and accurate control of orientation of ionic domains in nanostructured polymer electrolyte films and enables a platform for future studies that examines the relationship between polymer electrolyte structure and ion transport.

  20. New Technology for Preparation of High Purity Silver by Electrolysis Using Copper-ions Free Electrolyte%无铜离子电解制备高纯银新技术

    Institute of Scientific and Technical Information of China (English)

    王日; 黄绍勇; 聂华平

    2013-01-01

    Aiming at the problems of copper being hard to be further removed from electrolytic silver product ,the electrolytic silver using copper-ions free electrolyte was studied based on the copper ions action mechanism in silver electrolysis process .T he results show that no copper ions but adding reagents A and B in electrolyte ,the conductive properties of electrolyte and precipitation properties of electrolytic silver powder can be obviously improved ,current efficiency increases by 6 .5% ,and high purity silver product in which copper content is lower than 0 .000 5% can be acquired .%针对以电解法生产高纯银过程中杂质铜难以深度去除这一难题,在探明铜离子在银电解过程中的作用机制基础上,研究了以无铜离子电解体系电解银。试验结果表明:电解体系中无铜离子,通过添加试剂A、B,可以明显改善电解液的导电性能和电银粉的析出性能,电流效率提高6.5%,电银粉中铜质量分数低于0.0005%,产品质量符合IC-Ag99.99国家标准。

  1. Conductive dense hydrogen

    Science.gov (United States)

    Eremets, M.; Troyan, I.

    2012-12-01

    Hydrogen at ambient pressures and low temperatures forms a molecular crystal which is expected to display metallic properties under megabar pressures. This metal is predicted to be superconducting with a very high critical temperature Tc of 200-400 K. The superconductor may potentially be recovered metastably at ambient pressures, and it may acquire a new quantum state as a metallic superfluid and a superconducting superfluid. Recent experiments performed at low temperatures T 220 GPa, new Raman modes arose, providing evidence for the transformation to a new opaque and electrically conductive phase IV. Above 260 GPa, in the next phase V, hydrogen reflected light well. Its resistance was nearly temperature-independent over a wide temperature range, down to 30 K, indicating that the hydrogen was metallic. Releasing the pressure induced the metallic phase to transform directly into molecular hydrogen with significant hysteresis at 200 GPa and 295 K. These data were published in our paper: M. I. Eremets and I. A. Troyan "Conductive dense hydrogen." Nature Materials 10: 927-931. We will present also new results on hydrogen: phase diagram with phases IV and V determined in P,T domain up to 300 GPa and 350 K. We will also discuss possible structures of phase IV based on our Raman and infrared measurements up to 300 GPa.

  2. Dense Hypervelocity Plasma Jets

    Science.gov (United States)

    Case, Andrew; Witherspoon, F. Douglas; Messer, Sarah; Bomgardner, Richard; Phillips, Michael; van Doren, David; Elton, Raymond; Uzun-Kaymak, Ilker

    2007-11-01

    We are developing high velocity dense plasma jets for fusion and HEDP applications. Traditional coaxial plasma accelerators suffer from the blow-by instability which limits the mass accelerated to high velocity. In the current design blow-by is delayed by a combination of electrode shaping and use of a tailored plasma armature created by injection of a high density plasma at a few eV generated by arrays of capillary discharges or sparkgaps. Experimental data will be presented for a complete 32 injector gun system built for driving rotation in the Maryland MCX experiment, including data on penetration of the plasma jet through a magnetic field. We present spectroscopic measurements of plasma velocity, temperature, and density, as well as total momentum measured using a ballistic pendulum. Measurements are in agreement with each other and with time of flight data from photodiodes and a multichannel PMT. Plasma density is above 10^15 cm-3, velocities range up to about 100 km/s. Preliminary results from a quadrature heterodyne HeNe interferometer are consistent with these results.

  3. Seebeck effect in electrolytes.

    Science.gov (United States)

    Chikina, I; Shikin, V; Varlamov, A A

    2012-07-01

    We study Seebeck effect in liquid electrolytes, starting from its simple neutral analog--thermodiffusion (so-called Ludwig-Soret or Soret effect). It is observed that when two or more subsystems of mobile particles are subjected to the temperature gradient, various types of them respond to it differently. In the case when these fractions, with different mobility parameters (Soret coefficients), are oppositely charged (a case typical for electrolytes), the nonhomogeneous internal electric field is generated. The latter field prevents these fractions from space separation and determines the intensity of the appearing Seebeck effect.

  4. Ionic Liquid-Nanoparticle Hybrid Electrolytes and their Application in Secondary Lithium-Metal Batteries

    KAUST Repository

    Lu, Yingying

    2012-07-12

    Ionic liquid-tethered nanoparticle hybrid electrolytes comprised of silica nanoparticles densely grafted with imidazolium-based ionic liquid chains are shown to retard lithium dendrite growth in rechargeable batteries with metallic lithium anodes. The electrolytes are demonstrated in full cell studies using both high-energy Li/MoS2 and high-power Li/TiO2 secondary batteries. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Multichannel discharge between jet electrolyte cathode and jet electrolyte anode

    NARCIS (Netherlands)

    Shakirova, E. F.; Gaitsin, Al. F.; Son, E. E.

    2011-01-01

    We present the results of an experimental study of multichannel discharge between a jet electrolyte cathode and jet electrolyte anode within a wide range of parameters. We pioneer the reveal of the burning particularities and characteristics of multichannel discharge with jet electrolyte and droplet

  6. Thermal Decomposition of Dimethoxymethane Electrolyte Solution.

    Science.gov (United States)

    1982-06-01

    DIMETHOXYMETHANE ELECTROLYTE SOLUTION by J. S. Foos and V. Meltz Prepared for Publication in the Journal of the Electrochemical Society EIC...Journal of the Electrochemical Society . III. KEY WORDS (Conitiue onl reverse side It neci’eay and Identify by block nsinibor) Lithium Battery, Organic...Batteries, B. B. Owens and N. Margalit, eds., Vol. 80-4, The Electrochemical Society , Pennington, NJ, 384 (1980). .2. K. M. Abraham, J. L. Goldman and D. L

  7. Thermal stability of the C106 dye in robust electrolytes

    DEFF Research Database (Denmark)

    Lund, Torben; Phuong, Nguyen Tuyet; Pechy, Peter

    of the particles were prepared in electrolyte mixture B. The solutions were thermally treated at 80 ◦C for 0-2000 hours followed by dye extraction and analysis by HPLC coupled to UV/Vis and electro spray mass spectrometry [2]. Figure 1 shows the concentration profiles of C106 samples prepared under ambient...

  8. Heavy mesons in dense matter

    NARCIS (Netherlands)

    Tolos, Laura; Gamermann, Daniel; Garcia-Recio, Carmen; Molina, Raquel; Nieves, Juan; Oset, Eulogio; Ramos, Angels; LlanesEstrada, FJ; Pelaez,

    2011-01-01

    Charmed mesons in dense matter are studied within a unitary coupled-channel approach which takes into account Pauli-blocking effects and meson self-energies in a self-consistent manner. We obtain the open-charm meson spectral functions in this dense medium, and discuss their implications on hidden c

  9. Foaming-electrolyte fuel cell

    Science.gov (United States)

    Nanis, L.; Saunders, A. P.

    1970-01-01

    Foam structure feeds fuel gas solution into electrolyte. Fuel gas reacts at static, three-phase interface between fuel gas, electrolyte, and electrode material. The foam forms an electrical contact between main body of electrolyte and the electrode, and aids in removal of by-products of the chemical reaction.

  10. Preparation of (Sc{sub 2}O{sub 3}){sub 0.1}(CeO{sub 2}){sub 0.01}(ZrO{sub 2}){sub 0.89} ceramic hollow fiber for micro tubular solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Yang, N.T.; Meng, X.X.; Tan, X. [Shandong Univ. of Technology, Zibo (China). School of Chemical Engineering

    2010-07-01

    Due to their high volumetric power density, good mechanical properties, good thermocycling behaviour, and quick start-up and shut-down operations, micro tubular (MT) solid oxide fuel cells (SOFCs) have attracted significant interest. They may be applied in a variety of situations such as power sources for portable devices, uninterruptible power supplies and dynamical power sources for automobiles. Some effort has been placed on the research of anode and cathode supported tubular cells since a thin dense electrolyte membrane can be easily prepared on them, and a relative high power density can be obtained. However, electrolyte supported SOFCs have shown very good durability and reliability and high mechanical performances. When they are prepared into micro tubular or hollow fiber structure, their wall thicknesses will go down to 0.1 mm. If a unique electrolyte material is utilized to prepare a ceramic hollow fiber instead of traditional yttrium stabilized zirconium oxide (YSZ) material, better cell performance with an electrolyte supported structure can be achieved. This paper presented a study that synthesized the electrolyte powder of 1Ce{sub 10}ScZr with uniform size and a parasite structure using the EDTA-citric acid method. The paper described the experiment with particular reference to the preparation of material through a phase inversion/sintering technique. The morphology of the powder and the hollow fiber ceramics was determined by scanning electron microscopy. The performances of the powder were characterized by thermogravimetric/differential thermal analyzer, and X-ray diffraction. 5 refs.

  11. 复方聚乙二醇电解质散联合甘油灌肠剂用于妇科恶性肿瘤肠道准备临床观察%Clinical observation of polyethylene glycol electrolyte powder combined with glycerin enema in the bowel preparation for gynecology malignant tumor

    Institute of Scientific and Technical Information of China (English)

    韦冬英; 陈霞; 杨静秀

    2013-01-01

    Objective To observe the clinical effect of polyethylene glycol electrolyte powder combined with glycerin enema in the preoperative bowel preparation for gynecology malignant tumor. Methods 32 patients with gynecology malignant tumor were taken polyethylene glycol electrolyte powder solution orally, and given the glycerin enema before the operation. The adverse effects, bowel condition and postoperative anal exhaust time of patients were observed for evaluating the effect of bowel preparation. Results Applying polyethylene glycol electrolyte powder combined with glycerin enema in the preoperative bowel preparation for gynecology malignant tumor had good clinical effect, and few adverse effects. Conclusion Applying polyethylene glycol electrolyte powder combined with glycerin enema in the preoperative bowel preparation for gynecology malignant tumor is convenient, safe and effective, what's more, it also can avoid the pain of patients.%目的:观察复方聚乙二醇电解质散联合甘油灌肠剂在妇科恶性肿瘤术前肠道准备中的临床效果。方法32例接受妇科恶性肿瘤手术的患者,于手术前口服复方聚乙二醇电解质散溶液,联合甘油灌肠剂灌肠,观察患者不良反应、肠管状况、术后肛门排气时间评估肠道准备效果。结果复方聚乙二醇电解质散联合甘油灌肠剂用于妇科恶性肿瘤术前肠道准备具有好的临床效果,且副反应少。结论复方聚乙二醇电解质散联合甘油灌肠剂用于妇科恶性肿瘤术前肠道准备,方法简单,安全,有效,患者痛苦小。

  12. Proliferation and differentiation of osteoblast-like MC3T3-E1 cells on biomimetically and electrolytically deposited calcium phosphate coatings

    NARCIS (Netherlands)

    Wang, Jiawei; Boer, de Jan; Groot, de Klaas

    2008-01-01

    Biomimetic and electrolytic deposition are versatile methods to prepare calcium phosphate coatings. In this article, we compared the effects of biomimetically deposited octacalcium phosphate and carbonate apatite coatings as well as electrolytically deposited carbonate apatite coating on the prolife

  13. Hydrogel membrane electrolyte for electrochemical capacitors

    Indian Academy of Sciences (India)

    S Sampath; N A Choudhury; A K Shukla

    2009-09-01

    Polymer electrolytes are known to possess excellent physicochemical properties that are very useful for electrochemical energy systems. The mobility in polymer electrolytes is understood to be mainly due to the segmental motion of polymer chains and the ion transport is generally restricted to the amorphous phase of the polymer. Gel polymer electrolytes (GPE) that are formed using plastizicers and polymers along with ionic salts are known to exhibit liquid-like ionic conductivity while maintaining the dimensional stability of a solid matrix. In the present study, the preparation and characterization of poly(vinyl alcohol)-based hydrogel membranes (PHMEs) as electrolytes for electrochemical capacitors have been reported. Varying HClO4 dopant concentration leads to different characteristics of the capacitors. The EC comprising PHME doped with 2 M HClO4 and black pearl carbon (BPC) electrodes has been found to exhibit a maximum specific capacitance value of 97 F g-1, a phase angle value of 78°, and a maximum charge-discharge coulombic efficiency of 88%.

  14. Preparation and Characterization of TiO2 Nanotubes Array by Anodic Oxidation in Anionic Modified Glycerol-Based Electrolyte%阴离子改性甘油溶液中TiO2纳米管阵列的制备和表征

    Institute of Scientific and Technical Information of China (English)

    肖秀峰; 梁建鹤; 汤海贞; 杨小娟; 刘榕芳

    2013-01-01

    本文采用电化学阳极氧化法以含氟的甘油和水混合溶液为电解液在纯钛表面制备了一层排列规整的TiO2纳米管阵列,研究了电解液中额外添加3种2价阴离子、不同的电解时间及不同的添加物浓度等因素对所获得的TiO2纳米管阵列形貌的影响.结果表明,在改性电解液中制备的TiO2纳米管阵列的长度均超过了未改性的电解液中制备的,并随着氧化时间的增长,纳米管管口直径增大,管壁变薄;同时添加的(NH42TiF6浓度在0.025~0.1 mol·L-1范围内均可获得管长更长且形貌较好的TiO2纳米管阵列.%High-order T1O2 nanotube arrays on titanium foils were prepared in glycerol-based electrolyte containing fluorine and water by electrochemical anodic oxidation in this work. The influence of different dianion additives, different oxidation duration and concentration of electrolyte additives on the effect of the morphology of TiO2 nanotube arrays were investigated. Results showed that the length of TiO2 nanotube arrays in the modified electrolyte were longer than the samples in the unmodified electrolyte. And with the growth of oxidation duration, the diameter of the nanotubes increased, the wall were thinner; moreover better and longer TiO2 nanotube arrays can be prepared in the glycerol-based electrolyte with the range of the concentration of (NH4)2TiF6.

  15. Gel polymer electrolytes for batteries

    Science.gov (United States)

    Balsara, Nitash Pervez; Eitouni, Hany Basam; Gur, Ilan; Singh, Mohit; Hudson, William

    2014-11-18

    Nanostructured gel polymer electrolytes that have both high ionic conductivity and high mechanical strength are disclosed. The electrolytes have at least two domains--one domain contains an ionically-conductive gel polymer and the other domain contains a rigid polymer that provides structure for the electrolyte. The domains are formed by block copolymers. The first block provides a polymer matrix that may or may not be conductive on by itself, but that can soak up a liquid electrolyte, thereby making a gel. An exemplary nanostructured gel polymer electrolyte has an ionic conductivity of at least 1.times.10.sup.-4 S cm.sup.-1 at 25.degree. C.

  16. PVDF-HFP-based porous polymer electrolyte membranes for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Ruiying; Liu, Bowen; Zhu, Zhongzheng; Liu, Yun; Li, Jianling; Wang, Xindong [Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083 (China); Li, Qingfeng [Department of Chemistry, Technology University of Denmark, DK-2800 Lyngby (Denmark)

    2008-10-01

    As a potential electrolyte for lithium-ion batteries, a porous polymer electrolyte membrane based on poly(vinylidenefluoride-hexafluoropropylene) (PVDF-HFP) was prepared by a phase inversion method. The casting solution, effects of the solvent and non-solvent and addition of micron scale TiO{sub 2} particles were investigated. The membranes were characterized by SEM, XRD, AC impedance, and charge/discharge tests. By using acetone as the solvent and water as the non-solvent, the prepared membranes showed good ability to absorb and retain the lithium ion containing electrolyte. Addition of micron TiO{sub 2} particles to the polymer electrolyte was found to enhance the tensile strength, electrolyte uptake, ion conductivity and the electrolyte/electrode interfacial stability of the membrane. (author)

  17. Synthesis of and characterization of lithium ceramic electrolytes

    Science.gov (United States)

    Rangasamy, Ezhiylmurugan

    concentration on the crystal structure of LLZO were also studied in detail. Critical dopant concentration of Al to stabilize cubic LLZO was established during the course of this study. Systematic doping studies on the 24c site of La3+ in the primary lattice have also been explored in detail using XRD analysis to improve the ionic conductivity by maintaining the Li sub-lattice free of dopants. It is hypothesized that the supervalent substitutions create Li vacancies in the sub-lattice promoting disorder, thereby stabilizing cubic LLZO. While Ce4+ substitution for La3+ proved to be effective in synthesizing cubic LLZO, precipitation of Ce4+ observed under Backscattered electron (BSE) imaging limited its ionic conductivity. In an effort to develop flexible, solution-based synthetic techniques, two novel processes were established to prepare low dimensional, cubic LLZO powders. Hot pressing of the synthesized LLZO samples yielded high relative density (>95%) ceramic electrolyte membranes. Arrhenius studies using EIS to measure activation energy revealed and empirical relationship between the grain size and activation energy for dense LLZO membranes.

  18. Preparation and Performances of Room Molten Salt as Electrolyte in Carbon-carbon Capacitor Based on LiPFe and Trifluoroacetamide%LiPF6/三氟乙酰胺室温熔盐的制备及在碳-碳电容器中的性能

    Institute of Scientific and Technical Information of China (English)

    左晓希; 李奇; 刘建生; 肖信; 范成杰; 南俊民

    2012-01-01

    利用LiPF6和三氟乙酰胺为前驱物,制备了低共熔温度约为-62℃的室温熔盐,并测试了该熔盐作为碳-碳电化学电容器(EDLCs)电解液时的性能。其中,使用差示扫描量热法(DSC)和红外光谱法(FTIR)分析了不同LiPF6和三氟乙酰胺配比熔盐的热稳定性,拟制了该二元组分的共熔相图,认为LiPF6和三氟乙酰胺极性基团间的氢键作用促成了室温熔盐的形成。循环伏安(CV)、交流阻抗(EIS)和电导等测定结果表明,所制备的LiPF6/三氟乙酰胺电解液的室温电导率为1.30mS/cm,电化学窗口大于5.6V,大于60℃的使用温度,作为电解液可满足碳-碳EDLCs的使用要求。%A novel room molten salt with an eutectic temperature of about -62℃ is prepared using LiPF6 and trifluoroacetamide as precursors. And then its performances are evaluated in carbon-carbon electrochemical double layer capacitor (EDLC) as electrolyte. The thermal properties of the complex electrolyte with different molar ratios are characterized and then the liquid-solid phase diagram is presented by using differential scanning calorimeter (DSC) and Fourier transform infrared spectroscopy (FTIR). The hydrogen bonding interaction between LiPF6 and trifluoroacetamide molecules is attributed to the formation of the as-prepared molten salt. In addition, the results of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and conductance tests show that the as-prepared LiPF6/trifluoroacetamide electrolyte has a maximum conductance at room temperature, i.e. 1.30 mS/cm, a stable electrochemical window of ca. 5.6 V, an applicable temperature of more than 60℃, suggesting it is a promising electrolyte candidate for carbon-carbon EDLCs.

  19. Impedance Spectroscopy and FTIR Studies of PEG - Based Polymer Electrolytes

    Directory of Open Access Journals (Sweden)

    Anji Reddy Polu

    2011-01-01

    Full Text Available Ionic conductivity of poly(ethylene glycol (PEG - ammonium chloride (NH4Cl based polymer electrolytes can be enhanced by incorporating ceramic filler TiO2 into PEG-NH4Cl matrix. The electrolyte samples were prepared by solution casting technique. FTIR studies indicates that the complex formation between the polymer, salt and ceramic filler. The ionic conductivity was measured using impedance spectroscopy technique. It was observed that the conductivity of the electrolyte varies with TiO2 concentration and temperature. The highest room temperature conductivity of the electrolyte of 7.72×10−6 S cm-1 was obtained at 15% by weight of TiO2 and that without TiO2 filler was found to be 9.58×10−7 S cm−1. The conductivity has been improved by 8 times when the TiO2 filler was introduced into the PEG–NH4Cl electrolyte system. The conductance spectra shows two distinct regions: a dc plateau and a dispersive region. The temperature dependence of the conductivity of the polymer electrolytes seems to obey the VTF relation. The conductivity values of the polymer electrolytes were reported and the results were discussed. The imaginary part of dielectric constant (εi decreases with increase in frequency in the low frequency region whereas frequency independent behavior is observed in the high frequency region.

  20. Performances of the NASICON type solid-state electrolyte prepared by Kaolin doping and all solid-state lithium ion battery%高岭土掺杂NASICON固体电解质及全固态电池性能

    Institute of Scientific and Technical Information of China (English)

    郑卫东; 水淼; 任政娟; 舒杰; 徐丹; 张瑞丰

    2012-01-01

    To improve the low ionic conductivity of LiTi2(PO4)3 based solid state electrolyte, NASICON type fast ion conductors Li1+2x+2y, AlxMgy Ti2-x-ySixP3-r O12 were prepared by Mg2+ , Al3+ and Si4+ co-doping which originated from Kaolin of Zhejiang Sanmen district. The influences of the content of the doping elements and testing temperature on ionic conductivity were studied. The results show that ionic conductivity reaches maximum 7. 86×10-1 S · cm-1 tested at T=423 K for the composite Li1.8Al0.1 Mg0.3Ti1.6 Si0.1 P2.9O12· Spray Pyrolysis was applied to fabricate the in situ all solid -state lithium ion battery Al/ Li1+χV3O8/ Li1.8Al0.1 Mg0.3Ti1.6Si0.1P2.9O12/C system and 50 charge-discharge cycles were tested between 1. 8 -3. 9 V. The battery shows rather good stability and capacity retention capability. After 30 cycles, the discharge capacities are stabilized between 190 and 205 mAh · g-1 with more than 90% discharge efficiency.%针对LiTi2 (PO4)3基固态电解质电导率低的问题,采用浙江三门高岭土矿作为主要原料,以高温固相法制备铝、镁、硅共掺杂钠超离子导体(NASICON)型快离子导体Li1+2x+2yAlxMgy Ti2-x-ySixP3-xO12.研究掺杂比例、温度对固态电解质离子电导率的影响.结果表明,组成为Li1.8Al0.1Mg0.3Ti1.6Si0.1P2.9O12固体电解质在423 K时有最高离子电导率7.86×10-4 S· cm-1.以该组成固态电解质为基片,喷雾热解原位制备Al/ Li1+xV3 O8/Li1.8Al0.1Mg0.3 Ti1.6 Si0.1 P2.9O12/C全固态电池并在1.8~3.9V电压区间进行50次充放电测试.该电池具有较好的稳定性及循环容量保持能力.30次循环以后放电容量基本稳定在190~205 mAh·g-1之间,充放电效率大于90%.

  1. Electrolytes for advanced batteries

    Energy Technology Data Exchange (ETDEWEB)

    Blomgren, G.E. [Energizer, Westlake, OH (United States)

    1999-09-01

    The choices of the components of the electrolyte phase for advanced batteries (lithium and lithium ion batteries) are very sensitive to the electrodes which are used. There are also a number of other requirements for the electrolyte phase, which depend on the cell design and the materials chosen for the battery. The difficulty of choice is compounded when the cell is a rechargeable one. This paper looks at each of these requirements and the degree to which they are met for lithium and lithium ion batteries. The discussion is broken into sections on anode or negative electrode stability requirements, cathode or positive electrode stability requirements, conductivity needs, viscosity and wetting requirements. The effects of these properties and interactions on the performance of batteries are also discussed. (orig.)

  2. Nanoporous hybrid electrolytes

    KAUST Repository

    Schaefer, Jennifer L.

    2011-01-01

    Oligomer-suspended SiO2-polyethylene glycol nanoparticles are studied as porous media electrolytes. At SiO2 volume fractions, , bracketing a critical value y ≈ 0.29, the suspensions jam and their mechanical modulus increase by more than seven orders. For >y, the mean pore diameter is close to the anion size, yet the ionic conductivity remains surprisingly high and can be understood, at all , using a simple effective medium model proposed by Maxwell. SiO 2-polyethylene glycol hybrid electrolytes are also reported to manifest attractive electrochemical stability windows (0.3-6.3 V) and to reach a steady-state interfacial impedance when in contact with metallic lithium. © 2010 The Royal Society of Chemistry.

  3. Thin films of solid electrolytes and studies of their surface

    Science.gov (United States)

    Pan, Xiaoren; Gu, Zhi X.

    1991-11-01

    Much research work has been done on the materials of solid electrolytes and their applications. Solid electrolytes or fast ionic conductors are generally used in solid state batteries and solid state ionic devices. In the utilization of solid electrolytes, thin film forms have practical advantages. They will make the devices and batteries miniaturization which is particularly important for certain applications such as microelectronic devices, space programs, and integrated circuits of self-contained power. So preparation of thin films of solid electrolytes and studies of their surfaces are significant. There has been interest in the properties of amorphous ionic conductors, as glasses have acknowledged advantages over crystalline electrolytes, including physical isotropy, the absence of grain boundaries, and continuously-variable composition. Furthermore, many glasses based on silver halides have conductivities as high as 10 Scm-1 at room temperature. So we have chosen the quaternary system AgI-Ag2O-P2O5-B2O3 as the basic materials, prepared thin films, studied their properties, and constructed thin film electrolytic batteries.

  4. Reversible control of electrochemical properties using thermally-responsive polymer electrolytes.

    Science.gov (United States)

    Kelly, Jesse C; Pepin, Mark; Huber, Dale L; Bunker, Bruce C; Roberts, Mark E

    2012-02-14

    A thermally responsive copolymer is designed to modulate the properties of an electrolyte solution. The copolymer is prepared using pNIPAM, which governs the thermal properties, and acrylic acid, which provides the electrolyte ions. As the polymer undergoes a thermally activated phase transition, the local environment around the acid groups is reversibly switched, decreasing ion concentration and conductivity. The responsive electrolyte is used to control the activity of redox electrodes with temperature.

  5. Electrochemical polymer electrolyte membranes

    CERN Document Server

    Fang, Jianhua; Wilkinson, David P

    2015-01-01

    Electrochemical Polymer Electrolyte Membranes covers PEMs from fundamentals to applications, describing their structure, properties, characterization, synthesis, and use in electrochemical energy storage and solar energy conversion technologies. Featuring chapters authored by leading experts from academia and industry, this authoritative text: Discusses cutting-edge methodologies in PEM material selection and fabricationPoints out important challenges in developing PEMs and recommends mitigation strategies to improve PEM performanceAnalyzes the cur

  6. Electrolyte Concentrates Treat Dehydration

    Science.gov (United States)

    2009-01-01

    Wellness Brands Inc. of Boulder, Colorado, exclusively licensed a unique electrolyte concentrate formula developed by Ames Research Center to treat and prevent dehydration in astronauts returning to Earth. Marketed as The Right Stuff, the company's NASA-derived formula is an ideal measure for athletes looking to combat dehydration and boost performance. Wellness Brands also plans to expand with products that make use of the formula's effective hydration properties to help treat conditions including heat stroke, altitude sickness, jet lag, and disease.

  7. 含烷氧磺酸锂盐及对称星形醚的聚环氧乙烷基聚合物电解质的制备及电化学性能%Preparation and Electrochemical Performance of PEO Based Polymer Electrolyte Containing Pentaerythritol Tetrakis(2-methoxyethyl ether)and Lithium Methoxy Oligo(oxyethylene)sulfate

    Institute of Scientific and Technical Information of China (English)

    古宁宇; 余佃宝; 谢媛媛; 杨震宇; 张荣斌; 刘峰

    2011-01-01

    lithium methoxy oligo ( oxyethylene ) sulfate ( LiSA ( EO) n) and pentaerythritol tetrakis ( 2-methoxyethyl ether) (STEO) were synthesized and used for the preparation of polyethylene oxide (PEO) based polymer electrolytes. All solid-state polymer electrolytes PEO-LiSA (EO)n and PEO-LiClO4 were obtained by the solvent casting method and the ionic conductivities and lithium ion transference numbers were measured by using ac impedance and steady state current methods respectively. The influences of lithium salt structure on lithium ion transference numbers and ionic conductivities of polymer electrolytes were studied. Results showed that, comparing with LiClO4 , LiSA ( EO) n could enhance the ionic conductivity of polymer electrolytes and ionic conductivity decreased with increasing size of anion of lithium salt. Lithium ion transference numbers increased with increasing size of anion of lithium salt, and achieved a relatively high value of 0. 35 when (PEO16 + LiSA(EO)2) was used. Composed polymer electrolytes ( CPEs) PEO16-LiSAEO-STEO were prepared and the effects of addition of STEO on ionic conductivities were discussed. The experimental results showed that the addition of STEO could improve the ionic conductivity of the composited polymer electrolytes effectively, the ionic conductivity of PEO 16-LiSAEO-20%STEO achieved 0. 5 x 10-4 S/cm under 25℃. The thermal properties of CPEs were investigated by DSC experiments. Results indicated that the addition of STEO could decrease the melting temperature and crystallinity of CPE, resulting in the improvement of ionic conductivity. The electrochemical stability window of PEO16-liSAEO-20% STEO exceeded 4.4 V, which ensured the use of PEO16-LiSAEO-STEO as electrolyte materials for all solid-state rechargeable lithium ion batteries.%合成了低聚度烷氧磺酸锂盐(LiSA(EO)n)和对称星形醚(STEO)增塑剂,并制备了聚环氧乙烷(PEO)基聚合物电解质.研究了 PEO16+LiSA(EO)n体系的锂离子迁移数

  8. Research on sintering process of YSZ electrolyte

    Institute of Scientific and Technical Information of China (English)

    HAN Minfang; TANG Xiuling; PENG Suping

    2006-01-01

    Yttria stabilized zirconia (YSZ) has widely been used as electrolyte in solid oxide fuel cell (SOFC).The microstructure of YSZ related to the fabrication process was discussed in the paper.With YSZ nano-powders about 40-100 nm as raw material, the YSZ adobe was manufactured by tape calendering process.The named three-step sintering process was performed at 1000 ℃ for 2 h, then raised the temperature with normal rate and as soon as up to 1400 ℃, the furnace was controlled at 1250-1300 ℃ for 10-20 h.The high dense YSZs with the relative density of 96%-99% were obtained; the grain size of YSZ could be reduced to 0.5-3 μm.The above result is benefited to co-fired in the electrode-supported SOFCs.

  9. Dense energetic nitraminofurazanes.

    Science.gov (United States)

    Fischer, Dennis; Klapötke, Thomas M; Reymann, Marius; Stierstorfer, Jörg

    2014-05-19

    3,3'-Diamino-4,4'-bifurazane (1), 3,3'-diaminoazo-4,4'-furazane (2), and 3,3'-diaminoazoxy-4,4'-furazane (3) were nitrated in 100 % HNO3 to give corresponding 3,3'-dinitramino-4,4'-bifurazane (4), 3,3'-dinitramino-4,4'-azofurazane (5) and 3,3'-dinitramino-4,4'-azoxyfurazane (6), respectively. The neutral compounds show very imposing explosive performance but possess lower thermal stability and higher sensitivity than hexogen (RDX). More than 40 nitrogen-rich compounds and metal salts were prepared. Most compounds were characterized by low-temperature X-ray diffraction, all of them by infrared and Raman spectroscopy, multinuclear NMR spectroscopy, elemental analysis, and by differential scanning calorimetry (DSC). Calculated energetic performances using the EXPLO5 code based on calculated (CBS-4M) heats of formation and X-ray densities support the high energetic performances of the nitraminofurazanes as energetic materials. The sensitivities towards impact, friction, and electrostatic discharge were also explored. Additionally the general toxicity of the anions against vibrio fischeri, representative for an aquatic microorganism, was determined.

  10. Electrolyte materials - Issues and challenges

    Energy Technology Data Exchange (ETDEWEB)

    Balbuena, Perla B. [Department of Chemical Engineering, and Department of Materials Science and Engineering, Texas A and M University, College Station, Texas, 77843 (United States)

    2014-06-16

    Electrolytes are vital components of an electrochemical energy storage device. They are usually composed of a solvent or mixture of solvents and a salt or a mixture of salts which provide the appropriate environment for ionic conduction. One of the main issues associated with the selection of a proper electrolyte is that its electronic properties have to be such that allow a wide electrochemical window - defined as the voltage range in which the electrolyte is not oxidized or reduced - suitable to the battery operating voltage. In addition, electrolytes must have high ionic conductivity and negligible electronic conductivity, be chemically stable with respect to the other battery components, have low flammability, and low cost. Weak stability of the electrolyte against oxidation or reduction leads to the formation of a solid-electrolyte interphase (SEI) layer at the surface of the cathode and anode respectively. Depending on the materials of the electrolyte and those of the electrode, the SEI layer may be composed by combinations of organic and inorganic species, and it may exert a passivating role. In this paper we discuss the current status of knowledge about electrolyte materials, including non-aqueous liquids, ionic liquids, solid ceramic and polymer electrolytes. We also review the basic knowledge about the SEI layer formation, and challenges for a rational design of stable electrolytes.

  11. Dye-sensitized solar cell using 4-chloro-7-nitrobenzofurazan incorporated polyvinyl alcohol polymer electrolyte

    Science.gov (United States)

    Senthil, R. A.; Theerthagiri, J.; Madhavan, J.; Arof, A. K.

    2016-11-01

    The influence of 4-chloro-7-nitrobenzofurazan (CNBF) on ionic conductivity of polyvinyl alcohol/KI/I2 (PVA/KI/I2) electrolytes was investigated in the present study. The pure and CNBF incorporated PVA/KI/I2 electrolyte films were prepared by solution casting method using dimethyl sulfoxide as a solvent. These polymer electrolyte films were characterized using Fourier transform infrared spectroscopy, X-ray diffractometer, UV-Vis spectrophotometer and impedance analysis. The ionic conductivities of polymer electrolyte films were calculated from impedance analysis. The pure PVA/KI/I2 electrolyte exhibited the ionic conductivity of 1.649 × 10-5 S cm-1 at room temperature and this value was significantly increased to 1.490 × 10-4 S cm-1 when CNBF was incorporated into the PVA/KI/I2 electrolyte. This might be due to the decrease in the crystallinity of the polymer and increase in the ionic mobility of charge carriers. The performance of the DSSCs using both pure and CNBF incorporated PVA/KI/I2 electrolytes were compared. A DSSC fabricated with CNBF incorporated PVA/KI/I2 electrolyte showed an improved power conversion efficiency of 3.89 % than that of the pure PVA/KI/I electrolyte (1.51 %). These results suggest that CNBF incorporated PVA/KI/I2 electrolyte could be used as a potential electrolyte for DSSC.

  12. Preparation, transport and disposal of ash from coal-fired power plant Kosovo B in the form of dense hydromixture; Priprema, transport i deponovanje pepela termoelektrane Kosovo B u vidu guste hidromesavine

    Energy Technology Data Exchange (ETDEWEB)

    Drazovic, D.; Markovic, Z.; Stjepanovic, P.; Todorovtc, D. [Rudarski Institute, Beograd (Yugoslavia)

    1999-07-01

    The transportation of ash and slag from coal-fired power plants is mainly hydraulic. Until the eighties the most frequently applied technology was the transportation of ash and slag in the form of diluted hydromixture (concentration of solids below 10%). This method of ash and slag transportation became a rule in Yugoslavia's coal-fired power plants. It was not until 1988 that the transportation of dense hydromixture was introduced in the coal-fired power plant Gacko. This technology was not applied on account of its transportation advantages, but due to specific ash features that determine the conditions of disposal. Namely, the density of hydromixture is important for the solidification of disposed material. Considering the chemical and mineralogical properties of ash the same system was applied in the coal-fired power plant Kosovo B. In this paper two technological lines were installed and put to use in actual industrial conditions, and the results obtained indicate that all the designed parameters have been confirmed in practice and that the application of this technology has proven to be profitable in many ways. 7 refs., 8 figs., 13 tabs.

  13. Electrical characterization of proton conducting polymer electrolyte based on bio polymer with acid dopant

    Energy Technology Data Exchange (ETDEWEB)

    Kalaiselvimary, J.; Pradeepa, P.; Sowmya, G.; Edwinraj, S.; Prabhu, M. Ramesh, E-mail: email-mkram83@gmail.com [Department of Physics, Alagappa University, Karaikudi – 630 004, India. (India)

    2016-05-06

    This study describes the biodegradable acid doped films composed of chitosan and Perchloric acid with different ratios (2.5 wt %, 5 wt %, 7.5 wt %, 10 wt %) was prepared by the solution casting technique. The temperature dependence of the proton conductivity of complex electrolytes obeys the Arrhenius relationship. Proton conductivity of the prepared polymer electrolyte of the bio polymer with acid doped was measured to be approximately 5.90 × 10{sup −4} Scm{sup −1}. The dielectric data were analyzed using Complex impedance Z*, Dielectric loss ε’, Tangent loss for prepared polymer electrolyte membrane with the highest conductivity samples at various temperature.

  14. Easy Fabrication of Dense Ceramic Membrane for Oxygen Separation

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A combined EDTA-citrate complexing method was developed for the easy preparation of mixed oxygen-ionic and electronic conducting dense ceramic membrane for oxygen separation.The new method takes the advantage of lower calcination temperature for phase formation, lower membrane sintering temperature and higher relative density over the standard ceramic method.

  15. PVDF-Based Micro Inorganic Fillers-Containing Polymer Electrolyte Membranes

    Institute of Scientific and Technical Information of China (English)

    BAI Ying; WU Feng; WU Chuan

    2006-01-01

    Polymer electrolyte membranes based on poly (vinylidene fluoride-co-hexafluoropropylene) (PVDFHFP) with and without different types of micro inorganic fillers were prepared by phase-inversion process.Morphologies, porosities and electrochemical properties of the as-prepared membranes were investigated by means of scanning electronic microscopy (SEM), PC (propylene carbonate) uptake and alternating current(AC) impedance technique. Compared with other membranes, the membrane with micro SiO2 filler shows a dense morphology so that its PC uptake is the highest, namely, 339%. The membrane filled with micro TiO2exhibits good electrochemical performances: the ion conductivity is as high as 1.1 × 10-3 S/cm at 18 ℃,which can meet the demand of lithium ion batteries. Moreover, its initial charge-discharge efficiency exceeds89 %. The composite membranes with micro SiO2, TiO2 and A12O3 are more suitable for the utilization in lithium ion batteries due to better cycleability, whereas the battery assembled with the blank membrane containing no inorganic fillers encounters a short circuit after the 5th cycle.

  16. PVDF-HFP-based porous polymer electrolyte membranes for lithium-ion batteries

    DEFF Research Database (Denmark)

    Miao, Ruiying; Liu, Bowen; Zhu, Zhongzheng

    2008-01-01

    As a potential electrolyte for lithium-ion batteries, a porous polymer electrolyte membrane based on poly(vinylidenefluoride-hexafluoropropylene) (PVDF-HFP) was prepared by a phase inversion method. The casting solution, effects of the solvent and non-solvent and addition of micron scale TiO2 par...

  17. High performance silicon nanoparticle anode in fluoroethylene carbonate-based electrolyte for Li-ion batteries.

    Science.gov (United States)

    Lin, Yong-Mao; Klavetter, Kyle C; Abel, Paul R; Davy, Nicholas C; Snider, Jonathan L; Heller, Adam; Mullins, C Buddie

    2012-07-25

    Electrodes composed of silicon nanoparticles (SiNP) were prepared by slurry casting and then electrochemically tested in a fluoroethylene carbonate (FEC)-based electrolyte. The capacity retention after cycling was significantly improved compared to electrodes cycled in a traditional ethylene carbonate (EC)-based electrolyte.

  18. Electrical Grain Boundary Characteristics of Dense Cubic Li 7-3xAlxLa3Zr2O7 (x = 0.05 - 0.3) Prepared by Spark Plasma Sintering

    Science.gov (United States)

    Ibbotson, Matthew Gianni Equi

    In an effort to measure the electrical grain boundary characteristics of fully dense (˜99%) cubic Li 7-3xAlxLa3Zr 2O12 (x = 0.05 - 0.3), small grain size samples of 1 - 2mum were made using the Spark Plasma Sintering (SPS) method. The large internal interfacial area of SPS samples increased the grain boundary contribution to the total resistance to separate typically overlapping bulk and grain boundary impedance responses, supporting grain boundary conductivity (sigma GB) measurements. sigmaGBwas on average two orders of magnitude lower than the bulk conductivity (sigmabulk), indicating the grain boundaries of this material are resistive to Li+ transport, despite literature reports of low grain boundary resistance. sigmaGB = 3.8x10-7 +/- 11%, 7.9x10-7 +/- 11%, and 4.8x10-7 +/- 27% S/cm at 250C with corresponding EaGB = 0.44 +/- 3%, 0.49 +/- 4%, 0.46 +/- 2% eV, for 5, 20, and 30mol%Al 3+ LLZO, respectively. The electrical grain boundary thickness (delta GB) calculated using the Brick Layer Model decreased monotonically with aluminum concentration (CAl3+) to indicate a possible space-charge effect on sigmaGB, and was deltaGB = 10.2 +/- 18% , 9.9 +/- 12% , 6.0 +/- 20% nm for 5, 20, and 30mol%Al LLZO, respectively. Non-linear behavior of sigmaGB with CAl3+ was discussed in terms of competing space-charge and impurity segregation effects that simultaneously influence lithium conduction in the electrical GB. Optimum sigmaGB and sigmabulk of 7.9x10-7 +/- 11% and 4.6x10-4 +/- 4% S/cm at 250C, respectively, were found to coincide at CAl3+ = 20mol%, the critical aluminum dopant concentration for cubic LLZO phase stability.

  19. Electrolyte-induced reorganization of SDS self-assembly on graphene: a molecular simulation study.

    Science.gov (United States)

    Liu, Shuyan; Wu, Bin; Yang, Xiaoning

    2014-04-23

    A molecular dynamics simulation was conducted to study the structure and morphology of sodium dodecyl sulfate (SDS) surfactants adsorbed on a nanoscale graphene nanostructure in the presence of an electrolyte. The self-assembly structure can be reorganized by the electrolyte-induced effect. An increase in the ionic strength of the added electrolyte can enhance the stretching of adsorbed surfactants toward the bulk aqueous phase and make headgroups assemble densely, leading to a more compact structure of the SDS/graphene composite. The change in the self-assembly structure is attributed to the accumulation/condensation of electrolyte cations near the surfactant aggregate, consequently screening the electrostatic repulsion between charged headgroups. The role of the electrolyte revealed here provides direct microscopic evidence or an explanation of the reported experiments in the electrolyte tuning of the interfacial structure of a surfactant aggregate on the surface of carbon nanoparticles. Additionally, the buoyant density of the SDS/graphene assembly has been computed. With an increase in the ionic strength of the electrolyte, the buoyant density of the SDS/graphene composite rises. The interfacial accumulation of electrolytes provides an important contribution to the density enhancement. The study will be valuable for the dispersion and application of graphene nanomaterials.

  20. Optimized performance of quasi-solid-state DSSC with PEO-bismaleimide polymer blend electrolytes filled with a novel procedure.

    Science.gov (United States)

    Lee, Dong Ha; Sun, Kyung Chul; Qadir, Muhammad Bilal; Jeong, Sung Hoon

    2014-12-01

    Dye-sensitized solar cell (DSSC) is an attractive renewable energy technology currently under intense investigation. Electrolyte plays an important role in the photovoltaic performance of the DSSCs and many efforts have been contributed to study different kinds of electrolytes with various characteristics such as liquid electrolytes, polymer electrolytes and so on. In this study, DSSC is developed by using quasi-solid electrolyte and a novel procedure is adopted for filling this electrolyte. The quasi-solid-state electrolyte was prepared by mixing Poly ethylene oxide (PEO) and bismaleimide together and constitution was taken as PEO (15 wt%) at various bismaleimide concentrations (1, 3, 5 wt%). The novel procedure of filling electrolyte consists of three major steps (first step: filling liquid electrolyte, second step: vaporization of liquid electrolyte, third step: refilling quasi-solid-state electrolyte). The electrochemical and photovoltaic performances of DSSCs with these electrolytes were also investigated. The electrochemical impedance spectroscopy (EIS) indicated that TiO2/Dye/electrolyte impedance is reduced and electron lifetime is increased, and consequently efficiency of cell has been improved after using this novel procedure. The photovoltaic power conversion efficiency of 6.39% has been achieved under AM 1.5 simulated sunlight (100 W/cm2) through this novel procedure and by using specified blend of polymers.

  1. LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

    Energy Technology Data Exchange (ETDEWEB)

    Harlan U. Anderson; Fatih Dogan; Vladimir Petrovsky

    2002-03-31

    This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and testing of Planar Single Cells. This period has continued to address the problem of making dense 1/2 to 5 {micro}m thick dense layers on porous substrates (the cathode LSM). Our current status is that we are making structures of 2-5 cm{sup 2} in area, which consist of either dense YSZ or CGO infiltrated into a 2-5 {micro}m thick 50% porous layer made of either nanoncrystalline CGO or YSZ powder. This composite structure coats a macroporous cathode or anode; which serves as the structural element of the bi-layer structure. These structures are being tested as SOFC elements. A number of structures have been evaluated both as symmetrical and as button cell configuration. Results of this testing indicates that the cathodes contribute the most to cell losses for temperatures below 750 C. In this investigation different cathode materials were studied using impedance spectroscopy of symmetric cells and IV characteristics of anode supported fuel cells. Cathode materials studied included La{sub 0.8}Sr{sub 0.2}Co{sub 0.2}Fe{sub 0.8}O{sub 3} (LSCF), La{sub 0.7}Sr{sub 0.2}MnO{sub 3} (LSM), Pr{sub 0.8}Sr{sub 0.2}Fe{sub 0.8}O{sub 3} (PSCF), Sm{sub 0.8}Sr{sub 0.2}Co{sub 0.2}Fe{sub 0.8}O{sub 3} (SSCF), and Yb{sub .8}Sr{sub 0.2}Co{sub 0.2}Fe{sub 0.8}O{sub 3} (SSCF). A new technique for filtering the Fourier transform of impedance data was used to increase the sensitivity of impedance analysis. By creating a filter specifically for impedance spectroscopy the resolution was increased. The filter was tailored to look for specific circuit elements like R//C, Warburg, or constant phase elements. As many as four peaks can be resolved using the filtering technique on symmetric cells. It may be possible to relate the different peaks to material parameters, like the oxygen exchange coefficient. The cathode grouped in order from lowest to highest ASR is

  2. Gel-based composite polymer electrolytes with novel hierarchical mesoporous silica network for lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiaoliang; Cai Qiang [Department of Materials Science and Engineering, and State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084 (China); Fan Lizhen [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Hua Tao; Lin Yuanhua [Department of Materials Science and Engineering, and State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084 (China); Nan Cewen [Department of Materials Science and Engineering, and State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084 (China)], E-mail: cwnan@tsinghua.edu.cn

    2008-11-15

    In the present work, novel gel-based composite polymer electrolytes for lithium batteries were prepared by introducing a hierarchical mesoporous silica network to the poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP)-based gel electrolytes. As compared with the PVDF-HFP-based gel electrolytes with/without conventional nano-sized silica fillers, the novel electrolytes have shown more homogeneous microstructure, higher ionic conductivity and better mechanical stability, which could be caused by the strong silica network and the effective interactions among the polymer, the liquid electrolytes and the silica. Moreover, the cell with this kind of electrolytes could achieve a discharge capacity as much as 150 mAh g{sup -1} at room temperature (LiCoO{sub 2} as the cathode active material), with high Coulomb efficiency.

  3. Gel-based composite polymer electrolytes with novel hierarchical mesoporous silica network for lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiao-Liang; Cai, Qiang; Hua, Tao; Lin, Yuan-Hua; Nan, Ce-Wen [Department of Materials Science and Engineering, and State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084 (China); Fan, Li-Zhen [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China)

    2008-11-15

    In the present work, novel gel-based composite polymer electrolytes for lithium batteries were prepared by introducing a hierarchical mesoporous silica network to the poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP)-based gel electrolytes. As compared with the PVDF-HFP-based gel electrolytes with/without conventional nano-sized silica fillers, the novel electrolytes have shown more homogeneous microstructure, higher ionic conductivity and better mechanical stability, which could be caused by the strong silica network and the effective interactions among the polymer, the liquid electrolytes and the silica. Moreover, the cell with this kind of electrolytes could achieve a discharge capacity as much as 150 mAh g{sup -1} at room temperature (LiCoO{sub 2} as the cathode active material), with high Coulomb efficiency. (author)

  4. CONDUCTIVITY STUDIES OF (PEO +KHCO3 SOLID ELECTROLYTE SYSTEM AND ITS APPLICATION AS AN ELECTROCHEMICAL CELL

    Directory of Open Access Journals (Sweden)

    K. VIJAY KUMAR

    2010-06-01

    Full Text Available Solid polymer electrolyte system, polyethylene oxide (PEO complexed with potassium bicarbonate (KHCO3 salt was prepared by solution-cast technique. Several experimental techniques such as infrared radiation (IR, differential scanning calorimeter (DSC, and composition dependence conductivity, temperature dependence conductivity in the temperature range of 308–368 K and transport number measurements were employed to characterize this polymer electrolyte system. The conductivity of the (PEO+KHCO3 electrolyte was found to be about 3 times larger than that of pure PEO at room temperature. The transference data indicated that the charge transport in these polymer electrolyte systems is predominantly due to K+ ions. Using this polymer electrolyte an electrochemical cell with configuration K+/(PEO+KHCO3/(I2+C+electrolyte was fabricated and its discharge characteristics are studied. A number of other cell parameters associated with the cell were evaluated and are reported in this paper.

  5. A new type quasi-solid state electrolyte for dye-sensitized solar cells

    Institute of Scientific and Technical Information of China (English)

    WANG Miao; YANG Lei; ZHOU Xiaowen; LIN Yuan; LI Xueping; FENG Shujing; XIAO Xurui

    2006-01-01

    A new type quasi-solid state electrolyte was prepared by solidifying liquid electrolytes containing organic solvents (such as mixture of ethylene carbonate (EC) and propylene carbonate (PC), 3-methoxypropinitrile (NMP) and N-methyl-oxazolidinone (NMO)) with comb-like molten salt type polymer,and was for the first time employed in dyesensitized solar cells (DSSCs). The optimal electrolyte composition was obtained by regulating the polymer content in the electrolytes and optimizing performance data of the electrolytes and assembled cells, yielding a maximum conversion efficiency of 6.58% (AM 1.5,100 mW.cm-2). Furthermore, the existence of this new type polymer in the electrolyte suppresses the evaporation of organic solvent and improves the stability of the cells.

  6. Constructing dense genetic linkage maps

    NARCIS (Netherlands)

    Jansen, J.; Jong, de A.G.; Ooijen, van J.W.

    2001-01-01

    This paper describes a novel combination of techniques for the construction of dense genetic linkage maps. The construction of such maps is hampered by the occurrence of even small proportions of typing errors. Simulated annealing is used to obtain the best map according to the optimality criterion:

  7. Method for dense packing discovery.

    Science.gov (United States)

    Kallus, Yoav; Elser, Veit; Gravel, Simon

    2010-11-01

    The problem of packing a system of particles as densely as possible is foundational in the field of discrete geometry and is a powerful model in the material and biological sciences. As packing problems retreat from the reach of solution by analytic constructions, the importance of an efficient numerical method for conducting de novo (from-scratch) searches for dense packings becomes crucial. In this paper, we use the divide and concur framework to develop a general search method for the solution of periodic constraint problems, and we apply it to the discovery of dense periodic packings. An important feature of the method is the integration of the unit-cell parameters with the other packing variables in the definition of the configuration space. The method we present led to previously reported improvements in the densest-known tetrahedron packing. Here, we use the method to reproduce the densest-known lattice sphere packings and the best-known lattice kissing arrangements in up to 14 and 11 dimensions, respectively, providing numerical evidence for their optimality. For nonspherical particles, we report a dense packing of regular four-dimensional simplices with density ϕ=128/219≈0.5845 and with a similar structure to the densest-known tetrahedron packing.

  8. Unconditional Continuous Variable Dense Coding

    CERN Document Server

    Ralph, T C

    2002-01-01

    We investigate the conditions under which unconditional dense coding can be achieved using continuous variable entanglement. We consider the effect of entanglement impurity and detector efficiency and discuss experimental verification. We conclude that the requirements for a strong demonstration are not as stringent as previously thought and are within the reach of present technology.

  9. Gelled Electrolytes For Lithium Batteries

    Science.gov (United States)

    Nagasubramanian, Ganesan; Attia, Alan; Halpert, Gerald

    1993-01-01

    Gelled polymer electrolyte consists of polyacrylonitrile (PAN), LiBF4, and propylene carbonate (PC). Thin films of electrolyte found to exhibit stable bulk conductivities of order of 10 to the negative 3rd power S/cm at room temperature. Used in thinfilm rechargeable lithium batteries having energy densities near 150 W h/kg.

  10. Toughness of membranes applied in polymer electrolyte fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Kiefer, J.; Brack, H.P.; Scherer, G.G. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    Since several years we apply the radiation-grafting technique to prepare polymeric membranes for application in polymer electrolyte fuel cells (PEFCs). Our investigations presented here focus on changes in toughness of these materials after the various synthesis steps and the importance of membrane toughness for their application in PEFCs. (author) 2 figs., 4 refs.

  11. Novel Ceramic Materials for Polymer Electrolyte Membrane Water Electrolysers' Anodes

    DEFF Research Database (Denmark)

    Polonsky, J.; Bouzek, K.; Prag, Carsten Brorson

    2012-01-01

    Tantalum carbide was evaluated as a possible new support for the IrO2 for use in anodes of polymer electrolyte membrane water electrolysers. A series of supported electrocatalysts varying in mass content of iridium oxide was prepared. XRD, powder conductivity measurements and cyclic and linear sw...

  12. In-plant evaluation of dense medium process performances

    Energy Technology Data Exchange (ETDEWEB)

    R.Q. Honaker; A. Patwardhan [University of Kentucky, Lexington, KY (United States). Department of Mining Engineering

    2006-07-15

    The separation density and process efficiency values achieved by dense medium processes are a function of the particle size fractions being treated, hydrodynamics of the separator, and medium rheology. An in-plant evaluation of the dense medium processes being used in an operating preparation plant was conducted in an effort to develop relationships between the actual separation density and the medium density and to quantify the separation efficiency values. The results were found to correlate well with current fundamental and operating principles governing the processes, which are reviewed and discussed.

  13. Comparative study of formation and corrosion performance of porous alumina and ceramic nanorods formed in different electrolytes by anodization

    Energy Technology Data Exchange (ETDEWEB)

    Raj, V., E-mail: alaguraj2@rediffmail.com; Mumjitha, M., E-mail: mumjitha@gmail.com

    2014-01-15

    Highlights: • Alumina–titania coatings were fabricated by anodization in a single step. • The universal and cheap sulphuric acid was used as the reference electrolyte. • The minimum concentration of PTO is used to achieve ceramic nanorods. • Dense ceramic coatings were achieved at low current density and room temperature. • Anodized coatings show better corrosion resistance compared to bare aluminium. -- Abstract: Fabrication of Al{sub 2}O{sub 3}–TiO{sub 2} nanoceramic coatings on aluminium was carried out in a single step using cost effective sulphuric acid electrolyte with the addition of potassium titanium oxalate (PTO) by anodization method. For comparison, the anodization was also carried out in sulphuric acid electrolyte alone. The effect of composition of the electrolyte, current density and electrolyte concentration on formation and surface characteristics of anodic alumina and ceramic coatings produced from different electrolytes have been investigated. The growth process, surface morphology, nanostructure, distribution of chemical elements, phase constitutions and corrosion resistance of the coatings formed in two different electrolytes were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Tafel polarization technique and electrochemical impedance spectroscopy (EIS). As the concentration of electrolyte and current density increased, the surface properties of the coating increased up to certain content and beyond that they decreased. Dense, uniform nanoceramic coatings with less surface defects were obtained from sulphuric acid + PTO electrolyte. The corrosion studies reveal that ceramic coating formed in sulphuric acid + PTO electrolyte offers better corrosion resistance compared to the alumina coating formed in sulphuric acid electrolyte.

  14. Lithium batteries using poly(ethylene oxide)-based non-aqueous electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zonghai; Amine, Khalil

    2015-09-08

    Lithium-air cells employing poly(ethyleneoxide) phosphate-based electrolytes may be prepared and exhibit improved charge carrying capacity. Such PEO phosphates generally have the formulas IIa, IIb, IIc, where: ##STR00001##

  15. Synthesis and Ionic Conductivity of Network Polymer Electrolytes with Internal Plasticizers

    Institute of Scientific and Technical Information of China (English)

    Jun Jie KANG; Shi Bi FANG

    2004-01-01

    Network polymer electrolytes with free oligo(oxyethylene) chains as internal plasticizers were prepared by cross-linking poly(ethylene glycol) acrylates. The effects of salt concentration and properties of internal plasticizers on ionic conductivity were studied.

  16. Magnetron-Sputtered YSZ and CGO Electrolytes for SOFC

    Science.gov (United States)

    Solovyev, A. A.; Shipilova, A. V.; Ionov, I. V.; Kovalchuk, A. N.; Rabotkin, S. V.; Oskirko, V. O.

    2016-08-01

    Reactive magnetron sputtering has been used for deposition of yttria-stabilized ZrO2 (YSZ) and gadolinium-doped CeO2 (CGO) layers on NiO-YSZ commercial anodes for solid oxide fuel cells. To increase the deposition rate and improve the quality of the sputtered thin oxide films, asymmetric bipolar pulse magnetron sputtering was applied. Three types of anode-supported cells, with single-layer YSZ or CGO and YSZ/CGO bilayer electrolyte, were prepared and investigated. Optimal thickness of oxide layers was determined experimentally. Based on the electrochemical characteristics of the cells, it is shown that, at lower operating temperatures of 650°C to 700°C, the cells with single-layer CGO electrolyte are most effective. The power density of these fuel cells exceeds that of the cell based on YSZ single-layer electrolyte at the same temperature. Power densities of 650 mW cm-2 and 500 mW cm-2 at 700°C were demonstrated by cells with single-layer YSZ and CGO electrolyte, respectively. Significantly enhanced maximum power density was achieved in a bilayer-electrolyte single cell, as compared with cells with a single electrolyte layer. Maximum power density of 1.25 W cm-2 at 800°C and 1 W cm-2 at 750°C under voltage of 0.7 V were achieved for the YSZ/CGO bilayer electrolyte cell with YSZ and CGO thickness of about 4 μm and 1.5 μm, respectively. This signifies that the YSZ thin film serves as a blocking layer to prevent electrical current leakage in the CGO layer, leading to the overall enhanced performance. This performance is comparable to the state of the art for cells based on YSZ/CGO bilayer electrolyte.

  17. Study on new BaCe{sub 0.7}In{sub 0.3}O{sub 3−δ}–Gd{sub 0.1}Ce{sub 0.9}O{sub 2−δ} composite electrolytes for intermediate-temperature solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Fengguang; Dang, Junjie; Hou, Jie; Qian, Jing; Zhu, Zhiwen; Wang, Zhongtao [CAS Key Laboratory of Materials for Energy Conversion, Department of Material Science and Engineering, University of Science and Technology of China, Hefei 230026 (China); Liu, Wei, E-mail: wliu@ustc.edu.cn [CAS Key Laboratory of Materials for Energy Conversion, Department of Material Science and Engineering, University of Science and Technology of China, Hefei 230026 (China); Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2015-08-05

    Highlights: • New BCI–GDC composite electrolytes were synthesized using a one-step method for SOFCs. • The sintering temperature decreases as the BCI content increases. • The conductivity and OCV values enhanced as the GDC content increases. • The possible interface effects between BCI and GDC were analyzed. - Abstract: New mixed ionic conductors, BaCe{sub 0.7}In{sub 0.3}O{sub 3−δ}–Gd{sub 0.1}Ce{sub 0.9}O{sub 2−δ} (BCI–GDC, weight ratio, 3:7, 5:5 and 7:3), were synthesized via a one-step citric acid–nitrate gel combustion method as electrolyte materials for solid oxide fuel cells (SOFCs). X-ray diffraction patterns of BCI–GDC indicated that there was no impurity phase formed after sintering at high temperature up to 1400 °C. Scanning electron microscopic study of BCI–GDC depicted dense grain morphology. Single fuel cells were prepared and the corresponding electrochemical performances were tested. The sintering temperature of the dense composite electrolyte membranes decrease as the BCI content increases because of the sintering aids of In element. All samples with the composite electrolyte showed higher open circuit voltage (OCV) values than the single phase GDC. In addition, Electrical conductivity of the composite electrolyte under different atmospheres at different temperatures confirmed that the BCI–GDC exhibited high mixed oxygen ionic and protonic conduction. The test results indicated that the conductivity and OCV values of the composite electrolyte enhanced as the GDC content increases, and the optimum performance was found to be BCI3–GDC7 compared with the pure BCI and GDC electrolyte. The possible interface effects were suggested to explain this phenomenon. Our results not only provide one new promising composite electrolyte material for intermediate-temperature SOFCs but the composition dependence can actually provide a guide for the material design, optimization.

  18. Preparation of Alkaline Solid Polymer Electrolyte Based on PVA-TiO2-KOH-H2 O and Tts Application in Zn-Ni Battery%碱性固态聚合物电解质 PVA-TiO2-KOH-H2 O的制备及应用

    Institute of Scientific and Technical Information of China (English)

    贾若琨; 金鑫; 林松竹

    2013-01-01

    PVA-TiO2-KOH-H2 O alkaline solid polymer electrolyte separator is successfully prepared by the solution casting method.The properties of PVA-TiO2-KOH alkaline polymer electrolyte films were studied by scanning electron microscopy (SEM).The result showed that TiO2 particles dispersed into the PVA matrix although some TiO2 aggregates of several micrometers were formed.According to the research of the influence of water ratio and the amount of TiO2 ,it is found that the room tem-perature (20 ℃)ionic conductivity values of typical samples were 0.14 S/cm.The Zn-Ni secondary battery with the alkaline polymer electrolyte PVA-TiO2-KOH had a charging voltage of 4.2 V and a stable discharging voltage of 0.1 V.The Zn-Ni secondary battery with the alkaline polymer electrolyte PVA-TiO2-KOH had excellent electrochemical property at the low charge-discharge rate.%通过溶胶凝胶法制备一种新型的合成物,它基于 PVA高分子基质,TiO2陶瓷填料,KOH 和水。通过 SEM来研究这种高分子薄膜,结果显示 TiO2微粒散布到 PVA 基质中会形成一些只有几微米的TiO2聚合物。通过对含水率和TiO2添加量对隔膜性质的研究,得到室温下这种薄膜的离子电导率值为0.14 S/cm。组装的锌镍电池充电电压最高可达4.2 V,放电电压可到0.1 V,且十分稳定。使用这种电解质的锌镍二次电池在低充电放电率条件下电化学性能优越。

  19. Cathode-Electrolyte Interfaces with CGO Barrier Layers in SOFC

    DEFF Research Database (Denmark)

    Knibbe, Ruth; Hjelm, Johan; Menon, Mohan

    2010-01-01

    Electron microscopy characterization across the cathode–electrolyte interface of two different types of intermediate temperature solid oxide fuel cells (IT-SOFC) is performed to understand the origin of the cell performance disparity. One IT-SOFC cell had a sprayed-cosintered Ce0.90Gd0.01O1.95 (CGO......10) barrier layer, the other had a barrier layer deposited by pulsed laser deposition (PLD) CGO10. Scanning electron microscopy, transmission electron microscopy (TEM), and electron backscattered diffraction (EBSD) investigations conclude that the major source of the cell performance difference...... is attributed to CGO–YSZ interdiffusion in the sprayed-cosintered barrier layer. From TEM and EBSD work, a dense CGO10 PLD layer is found to be deposited epitaxially on the 8YSZ electrolyte substrate—permitting a small amount of SrZrO3 formation and minimizing CGO–YSZ interdiffusion....

  20. Stability of zirconia sol in the presence of various inorganic electrolytes

    Directory of Open Access Journals (Sweden)

    Marković Jelena P.

    2013-01-01

    Full Text Available Zirconia sol was prepared from zirconium oxychloride solutions by forced hydrolysis at 102ºC. The prepared sol consisted of almost spherical, monoclinic, hydrated zirconia particles 61 nm in diameter. The stability of zirconia sol in the presence of various inorganic electrolytes (LiCl, NaCl, KCl, CsCl, KBr, KI, KNO3, and K2SO4 was studied by potentiometric titration method. Dependence of the critical concentration of coagulation (CCC on the dispersion pH was determined for all studied electrolytes. The critical coagulation concentration values, for all investigated electrolytes, are lower at higher pH. These values for all 1:1 electrolytes are equal in the range of experimental error. For a given pH value, CCCs of K2SO4 are 3-4 orders of magnitude lower than the corresponding values for 1:1 electrolytes. [Projekat Ministarstva nauke republike Srbije, br. III 45012

  1. 智能电池电解液隔板用超疏水铜网的设计与制备%Design and Preparation of Superhydrophobic Copper mesh as Electrolyte Separators for Smart Batteries

    Institute of Scientific and Technical Information of China (English)

    徐钟凯; 黄熙; 谷长栋

    2012-01-01

    Facile galvanic replacement was adopted to grow dendrite coral-like silver films on commercial copper meshes.Silver films possess dual structure distinguished both in miacro and nano scales.After the immersion process in an ethanol solution of n-dodecanethiol,the rough silver films exhibit the superhydrophobic property with a contact angle of about 150°.Furthermore,such copper mesh can be used to be the electrolyte separator for smart batteries with the electrowetting process.At the storage phase of the battery,the copper mesh can effectively prevent the contact between the electrolyte and the electrodes.With a stimulation of external electric field,the wettability of the copper mesh can be changed from hydrophobicity to hydrophilicity,allowing the electrolyte contact the electrodes.Our study shows that the superhydrophobic copper mesh would have potential applications in smart batteries.%通过化学置换镀银的方法在金属铜网表面沉积银镀层以使其表面粗糙化,然后在十二烷硫醇/乙醇混合溶液中浸泡,进行低表面能物质的表面修饰,制备出接触角达到约150°的超疏水铜网。对该铜网的表面结构及超疏水性能进行了分析。利用超疏水表面的电致润湿特性,设计此铜网为智能电池的关键部件—电解液隔板。当智能电池在存储阶段,电解液隔板可以阻止电解液与电极接触,杜绝电池自放电的发生。当电池使用的时候,在外加电场刺激下,该铜网由疏水特性转变为亲水特性,从而使电解液自由通过此铜网。本研究对防止电池的自放电具有指导意义。

  2. Preparation of NiO-YSZ/YSZ bi-layers for solid oxide fuel cells by electrophoretic deposition

    Energy Technology Data Exchange (ETDEWEB)

    Besra, Laxmidhar; Zha, Shaowu; Liu, Meilin [School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive, Atlanta, GA 30332-0245 (United States)

    2006-09-29

    A simple and cost-effective method, starting with electrophoretic deposition (EPD) on a carbon sheet, has been developed for preparation of a NiO-YSZ anode and thin, gas-tight YSZ electrolyte layer on it for use in solid oxide fuel cells (SOFCs). The innovative feature of this approach enables the deposition of anode materials as well as the YSZ electrolyte, which were subsequently co-fired in air at high temperatures to remove the carbon and form an anode-supported dense YSZ electrolyte. A functional SOFC constructed by brush painting a layer of mixed cathode consisting of La{sub 0.8}Sr{sub 0.2}MnO{sub 3} (LSM) and YSZ on the electrolyte layer followed by firing at 1250{sup o}C, displayed a peak power density of 434mWcm{sup -2} at 800{sup o}C when tested with H{sub 2} as fuel and ambient air as oxidant. (author)

  3. 聚乙烯醇-磷酸-硅钨酸聚合物电解质膜的制备及电化学性能%Preparation of PVA-H3 PO4-STA Polymer Electrolyte Membranes and Their Electrochemical Properties

    Institute of Scientific and Technical Information of China (English)

    李长春; 田琦峰; 张飞

    2016-01-01

    采用溶液浇铸法制备聚乙烯醇(PVA)-磷酸(H3 PO4)-硅钨酸(STA)聚合物电解质膜,通过 X-射线衍射(XRD)、傅立叶变换红外光谱(FTIR)、热重分析(TGA)对聚合物电解质膜进行了表征,采用交流阻抗法测定聚合物电解质膜的质子电导率,并分析了 H3 PO4含量对质子电导率的影响。结果表明,当 STA含量不变时,随着 H3 PO4含量的增加,聚合物电解质膜的质子电导率先增大后减小;当m(PVA)∶m(H3 PO4)∶m(STA)=1∶4∶8时,在室温下质子电导率达到最大值,为5.50×10-2 S·cm-1;H3 PO4含量的增加使晶态 PVA转变为非晶态,晶态 PVA减少;循环伏安法和充放电测试结果表明,该聚合物电解质膜具有很好的电化学稳定性,有望应用于固态超级电容器。%Polyvinyl alcohol(PVA)-phosphoric acid(H3 PO4 )-silicotungstic acid(STA)polymer electrolyte membranes were prepared by a solution-casting method.The polymer electrolyte membranes were characterized by XRD,FTIR and TGA.The proton conductivity of the polymer electrolyte membranes was detected by an AC impedence method.Effect of H3 PO4 content on proton conductivity was also discussed.Results showed that pro-ton conductivity of the polymer electrolyte membranes increased firstly and then decreased with the increase of H3 PO4 content when the STA content was constant.When m(PVA)∶m(H3 PO4 )∶m(STA)was 1∶4∶8,the polymer electrolyte membranes exhibited the highest proton conductivity of 5.50×10-2 S·cm-1 at room tem-perature.While increasing H3 PO4 content,the crystallized PVA could be converted into amorphous phase,and content of the crystallized PVA reduced.The cyclic voltammograms and charge-discharge results indicated that the polymer electrolyte membranes had good electrochemical stability,and could be applied to solid supercapaci-tors.

  4. Electrolytes and thermoregulation

    Science.gov (United States)

    Nielsen, B.; Greenleaf, J. E.

    1977-01-01

    The influence of ions on temperature is studied for cases where the changes in ionic concentrations are induced by direct infusion or injection of electrolyte solutions into the cerebral ventricles or into specific areas of brain tissue; intravenous infusion or injection; eating food or drinking solutions of different ionic composition; and heat or exercise dehydration. It is shown that introduction of Na(+) and Ca(++) into the cerebral ventricles or into the venous system affects temperature regulation. It appears that the specific action of these ions is different from their osmotic effects. It is unlikely that their action is localized to the thermoregulatory centers in the brain. The infusion experiments demonstrate that the changes in sodium balance occurring during exercise and heat stress are large enough to affect sweat gland function and vasomotor activity.

  5. Comparison of Glauber′s salt and polyethylene glycol electrolyte powder on cleansing effect and tolerance in bowel ;preparation%芒硝与复方聚乙二醇电解质散在肠道准备中清洁效果及耐受性比较

    Institute of Scientific and Technical Information of China (English)

    张献文; 冯凯祥; 竹建强; 王秋蓉; 赵红

    2014-01-01

    Objective To compare the cleansing effect of Glauber′s salt and polyethylene glycol electrolyte powder in bowel preparation before colonoscopy and tolerance of patients. Methods A total of 2 380 patients with colonoscopy in outpatient service or hospitalized from August 2013 to May 2014 were selected and grouped according to the numbers of the last figure ,and the patients with odd figure(n=1 260) were given refined Glauber′s salt for bowel preparation(group A),while the patients with even figure(n=1 120) were given polyethylene glycol electrolyte powder for bowel preparation(group B). The cleaning effect and toler-ance to the laxatives in the two groups were compared. Results The difference on cleaning effect in the two groups had no statis tical significance(χ2=0.305 9,P>0.05);the tolerance of the patients in group A was better than that in group B with statistically significant difference(χ2=4.766 4,P<0.05). Conclusion The cleaning effect of Glauber′s salt was similar to that of polyethylene glycol electrolyte powder,but the patients with Glauber′s salt orally have better tolerance with less costs,so compared with polyethylene glycol electrolyte powder,Glauber′s salt has more advantages on bowel preparation.%目的:比较芒硝与复方聚乙二醇电解质散在结肠镜检查前肠道准备中的清洁效果及患者耐受性。方法选择2013年8月至2014年5月该院门诊及住院行结肠镜检查的2380例患者,按年龄末位数字的单双数进行分组,其中单数者(1260例)给予精制芒硝做肠道准备(A组),双数者(1120例)给予复方聚乙二醇电解质散做肠道准备(B组),比较两组肠道清洁效果和患者对清洁剂的耐受性。结果两组患者清洁剂使用后的肠道清洁有效率比较,差异无统计学意义(χ2=0.3059,P>0.05);A组患者耐受性较B组好,差异有统计学意义(χ2=4.7664,P<0.05)。结论芒硝与复方聚乙二醇电解质散在结

  6. Warm Dense Matter: An Overview

    Energy Technology Data Exchange (ETDEWEB)

    Kalantar, D H; Lee, R W; Molitoris, J D

    2004-04-21

    This document provides a summary of the ''LLNL Workshop on Extreme States of Materials: Warm Dense Matter to NIF'' which was held on 20, 21, and 22 February 2002 at the Wente Conference Center in Livermore, CA. The warm dense matter regime, the transitional phase space region between cold material and hot plasma, is presently poorly understood. The drive to understand the nature of matter in this regime is sparking scientific activity worldwide. In addition to pure scientific interest, finite temperature dense matter occurs in the regimes of interest to the SSMP (Stockpile Stewardship Materials Program). So that obtaining a better understanding of WDM is important to performing effective experiments at, e.g., NIF, a primary mission of LLNL. At this workshop we examined current experimental and theoretical work performed at, and in conjunction with, LLNL to focus future activities and define our role in this rapidly emerging research area. On the experimental front LLNL plays a leading role in three of the five relevant areas and has the opportunity to become a major player in the other two. Discussion at the workshop indicated that the path forward for the experimental efforts at LLNL were two fold: First, we are doing reasonable baseline work at SPLs, HE, and High Energy Lasers with more effort encouraged. Second, we need to plan effectively for the next evolution in large scale facilities, both laser (NIF) and Light/Beam sources (LCLS/TESLA and GSI) Theoretically, LLNL has major research advantages in areas as diverse as the thermochemical approach to warm dense matter equations of state to first principles molecular dynamics simulations. However, it was clear that there is much work to be done theoretically to understand warm dense matter. Further, there is a need for a close collaboration between the generation of verifiable experimental data that can provide benchmarks of both the experimental techniques and the theoretical capabilities

  7. Nanocomposite polymer electrolytes based on poly(oxyethylene and cellulose whiskers

    Directory of Open Access Journals (Sweden)

    My Ahmed Saïd Azizi Samir

    2005-06-01

    Full Text Available Solid lithium-conducting nanocomposite polymer electrolytes based on poly(oxyethylene (POE were prepared from high aspect ratio cellulosic whiskers and lithium imide salt, LiTFSI. The cellulosic whiskers were extracted from tunicate -a sea animal- and consisted of slender parallelepiped rods that have an average length around 1 µm and a width close to 15 nm. High performance nanocomposite electrolytes were obtained. The filler provided a high reinforcing effect while a high level of ionic conductivity was retained with respect to unfilled polymer electrolytes. Cross-linking and plasticizing of the matrix as well as preparation of the composites from an organic medium were also investigated.

  8. Dielectric behavior of different nanofillers incorporated in PVC-PMMA based polymer electrolyte membranes

    Science.gov (United States)

    Sowmya, G.; Pradeepa, P.; Kalaiselvimary, J.; Edwinraj, S.; Prabhu, M. Ramesh

    2016-05-01

    The Poly (methyl methacrylate) (PMMA)-Poly (vinyl chloride) (PVC) based polymer electrolytes were prepared by solvent casting technique. The prepared polymer electrolytes were subjected to conductivity studies by using electrochemical impedance spectroscopy and the maximum ionic conductivity value was found to be 0.8011 × 10-3 Scm-1 at 303K for PVC (17.5wt%) - PMMA (7.5wt %) - LiClO4 (8wt %) - PC (67wt %) - BaTiO3 (8wt%) electrolyte system. The dielectric behavior of the samples also studied.

  9. 一种新型固体聚合物电解质复合气体分离膜的制备及气体透过性能的研究%Preparation of new solid polymer electrolyte composite membrane and separation of propylene and propane

    Institute of Scientific and Technical Information of China (English)

    王雁北; 任吉中; 邓麦村

    2011-01-01

    采用单侧溶液交换法,把PEI/Pebax2533复合膜的Pebax2533外表面与AgBF4交换溶液接触,利用Ag+与Pebax2533分子链段中醚氧键之间的络合作用,将Ag+固定在PEI/Pebax2533复合膜中,从而制备了PEI/Pebax2533/AgBF4固体聚合物电解质复合气体分离膜.通过改变AgBF4交换溶液的浓度来调节复合膜表面银离子的负载量,控制复合膜对丙烯/丙烷的分离性能.随着AgBF4交换溶液浓度的增加,复合膜对烯烃出现明显的促进传递现象,塑性效应明显减弱.当AgBF4交换溶液浓度为8.0 mol/L时,PEI/Pebax2533/AgBF4复合膜丙烯/丙烷的分离系数远远超过1 000,塑性效应基本受到抑制.%A new solid polymer electrolyte PEI/Pebax2533/AgBF4 composite membrane is prepared with complexing method.By immersing the external surface of Pebax2533 layer of PEI/Pebax2533 composite membrane into AgBF4 solution, silver salt will transfer into Pebax2533 layer according to complexation with ether oxygen in Pebax2533 backbone, and a solid polymer electrolyte layer is formed.The silver salt content in the solid polymer electrolyte layer is dominated hy the AgBF4 concentration.The increase of AgBF4 concentration enhances carrier facilitated transport of propylene, and lowers its plasticization effect.For PEI/Pebax2533/AgBF4 composite membrane prepared with 8.0mol/L AgBF4 solution, its selectivity for propylene and propane is above 1000, and the plasticization effect is suppressed completely.

  10. Morphology of Polyvinylidene Fluoride Based Gel Polymer Electrolytes

    Institute of Scientific and Technical Information of China (English)

    田立颖; 黄小彬; 唐小真

    2004-01-01

    Two series of polyvinylidene fluoride (PVDF) based gel polymer electrolytes, with different LiClO4 or propylene carbonate (PC) content, were prepared and analyzed by infrared spectrometer, differential scanning calorimetry, scanning electron microscope and complex impedance spectrometer. The results show that there are great interactions between PVDF, PC and lithium cations. Both LiClO4 and PC content lead to evident change of the morphology of the gel polymer electrolytes. The content of LiClO4 and PC also influences the ionic conductivity of the samples,and an ionic conductivity of above 10-3S·cm-1 can be reached at room temperature.

  11. All-solid-state proton battery using gel polymer electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Kuldeep, E-mail: mishkuldeep@gmail.com [Department of Applied Science and Humanities, ABES Engineering College, Ghaziabad-201009, India and Department of Physics and Materials Science and Engineering, Jaypee Institute of Information Technology, Noida-201307 (India); Pundir, S. S.; Rai, D. K. [Department of Physics and Materials Science and Engineering, Jaypee Institute of Information Technology, Noida-201307 (India)

    2014-04-24

    A proton conducting gel polymer electrolyte system; PMMA+NH{sub 4}SCN+EC/PC, has been prepared. The highest ionic conductivity obtained from the system is 2.5 × 10−4 S cm{sup −1}. The optimized composition of the gel electrolyte has been used to fabricate a proton battery with Zn/ZnSO{sub 4}⋅7H{sub 2}O anode and MnO{sub 2} cathode. The open circuit voltage of the battery is 1.4 V and the highest energy density is 5.7 W h kg−1 for low current drain.

  12. Structural Transitions in Dense Networks

    CERN Document Server

    Lambiotte, R; Bhat, U; Redner, S

    2016-01-01

    We introduce an evolving network model in which a new node attaches to a randomly selected target node and also to each of its neighbors with probability $p$. The resulting network is sparse for $p<\\frac{1}{2}$ and dense (average degree increasing with number of nodes $N$) for $p\\geq \\frac{1}{2}$. In the dense regime, individual networks realizations built by this copying mechanism are disparate and not self-averaging. Further, there is an infinite sequence of structural anomalies at $p=\\frac{2}{3}$, $\\frac{3}{4}$, $\\frac{4}{5}$, etc., where the dependences on $N$ of the number of triangles (3-cliques), 4-cliques, undergo phase transitions. When linking to second neighbors of the target can occur, the probability that the resulting graph is complete---where all nodes are connected---is non-zero as $N\\to\\infty$.

  13. Holographic Renormalization in Dense Medium

    Directory of Open Access Journals (Sweden)

    Chanyong Park

    2014-01-01

    describes a dense medium at finite temperature, is investigated in this paper. In a dense medium, two different thermodynamic descriptions are possible due to an additional conserved charge. These two different thermodynamic ensembles are classified by the asymptotic boundary condition of the bulk gauge field. It is also shown that in the holographic renormalization regularity of all bulk fields can reproduce consistent thermodynamic quantities and that the Bekenstein-Hawking entropy is nothing but the renormalized thermal entropy of the dual field theory. Furthermore, we find that the Reissner-Nordström AdS black brane is dual to a theory with conformal matter as expected, whereas a charged black brane with a nontrivial dilaton profile is mapped to a theory with nonconformal matter although its leading asymptotic geometry still remains as AdS space.

  14. Radiative properties of dense nanofluids.

    Science.gov (United States)

    Wei, Wei; Fedorov, Andrei G; Luo, Zhongyang; Ni, Mingjiang

    2012-09-01

    The radiative properties of dense nanofluids are investigated. For nanofluids, scattering and absorbing of electromagnetic waves by nanoparticles, as well as light absorption by the matrix/fluid in which the nanoparticles are suspended, should be considered. We compare five models for predicting apparent radiative properties of nanoparticulate media and evaluate their applicability. Using spectral absorption and scattering coefficients predicted by different models, we compute the apparent transmittance of a nanofluid layer, including multiple reflecting interfaces bounding the layer, and compare the model predictions with experimental results from the literature. Finally, we propose a new method to calculate the spectral radiative properties of dense nanofluids that shows quantitatively good agreement with the experimental results.

  15. Dilatons for Dense Hadronic Matter

    CERN Document Server

    Lee, Hyun Kyu

    2009-01-01

    The idea that the explicit breaking of scale invariance by the trace anomaly of QCD can be rephrased as a spontaneous breaking has been recently exploited to capture the low-energy strong interaction dynamics of dense (and also hot) matter in terms of two dilaton fields, the "soft" (chi_s) and the "hard" (chi_h) fields, in the frame work of the hidden local gauge symmetry. In the Freund-Nambu model, the spontaneous symmetry breaking of scale symmetry is induced by an explicitly breaking term, while the spontaneous symmetry breaking is possible in the flat potential model which is scale symmetric. We discuss the interplay of the soft and hard dilatons using the spontaneously broken scale symmetry schemes and uncover a novel structure of dense matter hitherto unexplored.

  16. Preparation of dense nanocrystalline Bi{sub 2}O{sub 3}-HfO{sub 2}-Y{sub 2}O{sub 3} ceramic by microwave plasma sintering

    Energy Technology Data Exchange (ETDEWEB)

    Zhen Qiang [Nano-Science and Nano-Technology Research Center, School of Materials Science and Engineering, Shanghai University, Shanghai 200444 (China)]. E-mail: qzhen@staff.shu.edu.cn; Vannier, Rose Noelle [Laboratoire de Cristallochimie et Physicochimie du Solide, UPRESA-CNRS 8012 ENSCL-USTL, BP 108, 59652 Villeneuve d' Ascq Cedex (France); Kale, Girish M. [Institute for Materials Research, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2007-01-25

    Processing of nanocrystalline Bi{sub 2}O{sub 3}-HfO{sub 2}-Y{sub 2}O{sub 3} ceramic having high density has been investigated and reported in this paper. Nanopowders of mixed bismuth oxide, hafnia and yttrium oxide have been prepared by a reverse titration chemical coprecipitation from Bi{sup 3+}, Hf{sup 4+} and Y{sup 3+} containing aqueous solution. The high density, nanocrystalline Bi{sub 2}O{sub 3}-HfO{sub 2}-Y{sub 2}O{sub 3} ceramic has been synthesized by microwave plasma sintering. The XRD results of grain growth behavior indicates that growth of both {delta}-Bi{sub 2}O{sub 3} and c-HfO{sub 2} crystallites obeys the parabolic rate law, expressed as (D-D {sub 0}){sup 2} = Kt, during sintering process. After sintering at 700 deg. C for 60 min, the relative density of the samples sintered by microwave plasma has been found to be greater than 97%, and the samples exhibit considerably finer microstructure with an average size between 60 and 70 nm and equiaxed morphology and better density comparing with that of samples sintered by conventional pressureless sintering. In addition, mechanical properties of nanocrystalline Bi{sub 2}O{sub 3}-HfO{sub 2}-Y{sub 2}O{sub 3} ceramic has been improved greatly compareing with nanocrystalline Bi{sub 2}O{sub 3}-Y{sub 2}O{sub 3} ceramic.

  17. Optimization of the interface polarization of the La{sub 2}NiO{sub 4}-based cathode working with the Ce{sub 1-x}Sm{sub x}O{sub 2-{delta}} electrolyte system

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Coll, D.; Aguadero, A.; Escudero, M.J. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Av. Complutense 22, 28040 Madrid (Spain); Nunez, P. [Dpto. Quimica Inorganica, Universidad de La Laguna, 38200 La Laguna, Tenerife (Spain); Daza, L. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Av. Complutense 22, 28040 Madrid (Spain); Instituto de Catalisis y Petroleoquimica (CSIC), Marie-Curie 2, Campus Cantoblanco, 28049 Madrid (Spain)

    2008-03-15

    The performance of La{sub 2}NiO{sub 4} cathode material and Ce{sub 1-x}Sm{sub x}O{sub 2-{delta}} (x = 0.1, 0.2, 0.3, 0.4) electrolyte system was analyzed. Ceria-based materials were prepared by the freeze-drying precursor route whereas La{sub 2}NiO{sub 4} was prepared by the nitrate-citrate procedure. Electrolyte pellets were obtained after sintering the powders at 1600 C for 10 h. Also dense ceria-based electrolytes samples were obtained by calcining the powders at 1150 C after the addition of 2 mol%-Co. Interface polarization measurements were performed by impedance spectroscopy in air at open circuit voltage, using symmetrical cells prepared after the deposition of porous La{sub 2}NiO{sub 4}-electrodes on the Ce{sub 1-x}Sm{sub x}O{sub 2-{delta}} system. X-ray diffraction (XRD) of cathode materials after using in symmetrical cells confirmed no significant reaction between La{sub 2}NiO{sub 4} and ceria-based electrolytes. The efficiency of the cathode material is highly dependent on the composition of the electrolyte, and low-content Sm-doped ceria samples revealed an important decrease in the performance of the system. Differences in electrochemical behaviour were attributed principally to the oxide ion transference between cathode and electrolyte, and were correlated to the conductivity of the electrolyte. In this way cobalt-doped electrolytes with a Sm-content {<=}30% perform better than free-cobalt samples due to the increase in grain boundary conductivity. Finally, composites of the ceria-based materials and La{sub 2}NiO{sub 4} to use as cathode were prepared and an important increase of the interface performance was observed compared to La{sub 2}NiO{sub 4} pure cathode. Predictions of maximun power density were obtained by the mixed transport properties of the electrolytes and by the interface polarization results. The use of composite materials could allow to increase the performance of the cell from 170 mW cm{sup -2} for pure La{sub 2}NiO{sub 4} cathode

  18. Photopolymerized Electrolytes For Electrochromic Devices

    Science.gov (United States)

    Cogan, Stuart; Rauh, R. David

    1994-01-01

    Thin ion-conducting electrolyte films for use in electrochromic devices now fabricated relatively easily and quickly with any of class of improved formulations containing ultraviolet-polymerizable components. Formulations are liquids in their monomeric forms and self-supporting, transparent solids in their polymeric forms. Thin solid electrolytes form quickly and easily between electrode-bearing substrates. Film thus polymerized acts not only as solid electrolyte but also as glue holding laminate together: feature simplifies fabrication by reducing need for sealants and additional mechanical supports.

  19. Organic electrolytes for sodium batteries

    Science.gov (United States)

    Vestergaard, B.

    1992-09-01

    A summary of earlier given status reports in connection with the project on organic electrolytes for sodium batteries is presented. The aim of the investigations was to develop new room temperature molten salts electrolytes mainly with radical substituted heterocyclic organic chlorides mixed with aluminum chloride. The new electrolytes should have an ionic conductivity comparable with MEIC1:AlCl3 or better. A computer model program MOPAC (Molecular Orbital Package) was to be included to calculate theoretically reduction potentials for a variety of organic cations. Furthermore, MOPAC could be utilized to predict the electron densities, and then give a prediction of the stability of the organic cation.

  20. Electrospun nanocomposite fibrous polymer electrolyte for secondary lithium battery applications

    Energy Technology Data Exchange (ETDEWEB)

    Padmaraj, O.; Rao, B. Nageswara; Jena, Paramananda; Satyanarayana, N., E-mail: nallanis2011@gmail.com [Department of Physics, Pondicherry University, Pondicherry-605014 (India); Venkateswarlu, M. [R and D, Amaraja batteries, Thirupathi-517501 (India)

    2014-04-24

    Hybrid nanocomposite [poly(vinylidene fluoride -co- hexafluoropropylene) (PVdF-co-HFP)/magnesium aluminate (MgAl{sub 2}O{sub 4})] fibrous polymer membranes were prepared by electrospinning method. The prepared pure and nanocomposite fibrous polymer electrolyte membranes were soaked into the liquid electrolyte 1M LiPF{sub 6} in EC: DEC (1:1,v/v). XRD and SEM are used to study the structural and morphological studies of nanocomposite electrospun fibrous polymer membranes. The nanocomposite fibrous polymer electrolyte membrane with 5 wt.% of MgAl{sub 2}O{sub 4} exhibits high ionic conductivity of 2.80 × 10{sup −3} S/cm at room temperature. The charge-discharge capacity of Li/LiCoO{sub 2} coin cells composed of the newly prepared nanocomposite [(16 wt.%) PVdF-co-HFP+(5 wt.%) MgAl{sub 2}O{sub 4}] fibrous polymer electrolyte membrane was also studied and compared with commercial Celgard separator.

  1. An electrolyte CPA equation of state for mixed solvent electrolytes

    DEFF Research Database (Denmark)

    Maribo-Mogensen, Bjørn; Thomsen, Kaj; Kontogeorgis, Georgios M.

    2015-01-01

    that the predictive capabilities could be improved through the development of an electrolyte equation of state. In this work, the Cubic Plus Association (CPA) Equation of State is extended to handle mixtures containing electrolytes by including the electrostatic contributions from the Debye-Hückel and Born terms...... depression. Finally, the model is applied to predict VLE, LLE, and SLE in aqueous salt mixtures as well as in mixed solvents....

  2. Alkaline solid polymer electrolytes and their application to rechargeable batteries; Electrolytes solides polymeres alcalins application aux generateurs electrochimiques rechargeables

    Energy Technology Data Exchange (ETDEWEB)

    Guinot, S.

    1996-03-15

    A new family of solid polymer electrolytes (SPE) based on polyoxyethylene (POE), KOH and water is investigated in view of its use in rechargeable batteries. After a short review on rechargeable batteries, the preparation of various electrolyte compositions is described. Their characterization by differential scanning calorimetry (DSC), thermogravimetric analysis, X-ray diffraction and microscopy confirm a multi-phasic structure. Conductivity measurements give values up to 10 sup -3 S cm sup -1 at room temperature. Their use in cells with nickel as negative electrode and cadmium or zinc as positive electrode has been tested; cycling possibility has been shown to be satisfactory. (C.B.) 113 refs.

  3. Non-aqueous electrolytes for electrochemical cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhengcheng; Dong, Jian; Amine, Khalil

    2016-06-14

    An electrolyte electrochemical device includes an anodic material and an electrolyte, the electrolyte including an organosilicon solvent, a salt, and a hybrid additiving having a first and a second compound, the hybrid additive configured to form a solid electrolyte interphase film on the anodic material upon application of a potential to the electrochemical device.

  4. Organic dopant added polyvinylidene fluoride based solid polymer electrolytes for dye-sensitized solar cells

    Science.gov (United States)

    Senthil, R. A.; Theerthagiri, J.; Madhavan, J.

    2016-02-01

    The effect of phenothiazine (PTZ) as dopant on PVDF/KI/I2 electrolyte was studied for the fabrication of efficient dye-sensitized solar cell (DSSC). The different weight percentage (wt%) ratios (0, 20, 30, 40 and 50%) of PTZ doped PVDF/KI/I2 electrolyte films were prepared by solution casting method using DMF as a solvent. The following techniques such as Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC), X-ray diffractometer (XRD) and AC-impedance analysis have been employed to characterize the prepared polymer electrolyte films. The FT-IR studies revealed the complex formation between PVDF/KI/I2 and PTZ. The crystalline and amorphous nature of polymer electrolytes were confirmed by DSC and XRD analysis respectively. The ionic conductivities of polymer electrolyte films were calculated from the AC-impedance analysis. The undoped PVDF/KI/I2 electrolyte exhibited the ionic conductivity of 4.68×10-6 S cm-1 and this value was increased to 7.43×10-5 S cm-1 when PTZ was added to PVDF/KI/I2 electrolyte. On comparison with different wt% ratios, the maximum ionic conductivity was observed for 20% PTZ-PVDF/KI/I2 electrolyte. A DSSC assembled with the optimized wt % of PTZ doped PVDF/KI/I2 electrolyte exhibited a power conversion efficiency of 2.92%, than the undoped PVDF/KI/I2 electrolyte (1.41%) at similar conditions. Hence, the 20% PTZ-PVDF/KI/I2 electrolyte was found to be optimal for DSSC applications.

  5. Characteristics of MOX dissolution with silver mediated electrolytic oxidation method

    Energy Technology Data Exchange (ETDEWEB)

    Umeda, Miki; Nakazaki, Masato; Kida, Takashi; Sato, Kenji; Kato, Tadahito; Kihara, Takehiro; Sugikawa, Susumu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    MOX dissolution with silver mediated electrolytic oxidation method is to be applied to the preparation of plutonium nitrate solution to be used for criticality safety experiments at Nuclear Fuel Cycle Safety Engineering Research Facility (NUCEF). Silver mediated electrolytic oxidation method uses the strong oxidisation ability of Ag(II) ion. This method is though to be effective for the dissolution of MOX, which is difficult to be dissolved with nitric acid. In this paper, the results of experiments on dissolution with 100 g of MOX are described. It was confirmed from the results that the MOX powder to be used at NUCEF was completely dissolved by silver mediated electrolytic oxidation method and that Pu(VI) ion in the obtained solution was reduced to tetravalent by means of NO{sub 2} purging. (author)

  6. Destabilization Mechanism of Ionic Surfactant on Curcumin Nanocrystal against Electrolytes

    Science.gov (United States)

    Rachmawati, Heni; Rahma, Annisa; Al Shaal, Loaye; Müller, Rainer H.; Keck, Cornelia M.

    2016-01-01

    We have successfully developed curcumin nanosuspension intended for oral delivery. The main purpose is to improve bioavailability through enhancing its solubility. The nanoparticles were stabilized using various stabilizers, including polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), sodium carboxymethylcellulose (Na-CMC), d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS), and sodium dodecyl sulfate (SDS). The average diameter of particles, microscopic appearance, and sedimentation of each preparation was observed and compared. Each stabilizer demonstrated a different degree of inhibition of particle aggregation under electrolyte-containing simulated gastrointestinal (GIT) fluid. Non-ionic stabilizers (PVA, PVP, and TPGS) were shown to preserve the nanosuspension stability against electrolytes. In contrast, strong ionic surfactants such as SDS were found to be very sensitive to electrolytes. The results can provide useful information for the formulators to choose the most suitable stabilizers by considering the nature of stabilizers and physiological characteristics of the target site of the drug. PMID:27763572

  7. Destabilization Mechanism of Ionic Surfactant on Curcumin Nanocrystal against Electrolytes

    Directory of Open Access Journals (Sweden)

    Heni Rachmawati

    2016-10-01

    Full Text Available We have successfully developed curcumin nanosuspension intended for oral delivery. The main purpose is to improve bioavailability through enhancing its solubility. The nanoparticles were stabilized using various stabilizers, including polyvinyl pyrrolidone (PVP, polyvinyl alcohol (PVA, sodium carboxymethylcellulose (Na-CMC, d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS, and sodium dodecyl sulfate (SDS. The average diameter of particles, microscopic appearance, and sedimentation of each preparation was observed and compared. Each stabilizer demonstrated a different degree of inhibition of particle aggregation under electrolyte-containing simulated gastrointestinal (GIT fluid. Non-ionic stabilizers (PVA, PVP, and TPGS were shown to preserve the nanosuspension stability against electrolytes. In contrast, strong ionic surfactants such as SDS were found to be very sensitive to electrolytes. The results can provide useful information for the formulators to choose the most suitable stabilizers by considering the nature of stabilizers and physiological characteristics of the target site of the drug.

  8. Poly(hydroxyethyl methacrylate) based networked solid polymer electrolyte.

    Science.gov (United States)

    Lee, A-Ran; Kim, Young-Deok; Lee, Sang-Keol; Jo, Nam-Ju

    2013-10-01

    Solid polymer electrolytes (SPEs) have good safety for lithium battery compared to liquid electrolytes, but they have low ionic conductivity. To solve the problem, the polymer-in-salt system was introduced which has higher ionic conductivity than salt-in-polymer system. However, polymer-in-salt system has disadvantages that are poor mechanical properties with increasing salt concentration. In this study, networked polymer electrolytes consisting of poly(hydroxyethyl methacrylate) (P(HEMA)), lithium triflate (LiCF3SO3, LiTf) and hydrochloric acid (HCl) were prepared. And the electrochemical and mechanical properties of P(HEMA) based SPEs were investigated by using ac impedance analyzer and universal testing machine, respectively.

  9. Pressureless reactive sintering mechanism of nanocrystalline Bi2O3-Y2O3 solid electrolyte

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The nanocrystalline Bi2O3-Y2O3 solid electrolyte material was synthesized by pressureless reactive sintering process with Bi2O3 and Y2O3 nano mixed powder as raw materials, which was prepared by a chemical coprecipitation process. The study on the behavior of nano δ-Bi2O3 formation and its grain growth showed that the solid solution reaction of Y2O3 and β-Bi2O3 to form δ-Bi2O3occurs mainly in the initial stage of sintering process, and nano δ-Bi2O3 crystal grains grow approximately following the rule of paracurve ((D-D0)2=K.t) during sintering process. After sintered at 600℃ for 2 h, the samples could reach above 96% in relative density and have dense microstructure with few remaining pores, the δ-Bi2O3 grains are less than 100 nm in size.

  10. Composite solid polymer electrolyte membranes

    Energy Technology Data Exchange (ETDEWEB)

    Formato, Richard M. (Shrewsbury, MA); Kovar, Robert F. (Wrentham, MA); Osenar, Paul (Watertown, MA); Landrau, Nelson (Marlborough, MA); Rubin, Leslie S. (Newton, MA)

    2001-06-19

    The present invention relates to composite solid polymer electrolyte membranes (SPEMs) which include a porous polymer substrate interpenetrated with an ion-conducting material. SPEMs of the present invention are useful in electrochemical applications, including fuel cells and electrodialysis.

  11. Constructing Dense Graphs with Unique Hamiltonian Cycles

    Science.gov (United States)

    Lynch, Mark A. M.

    2012-01-01

    It is not difficult to construct dense graphs containing Hamiltonian cycles, but it is difficult to generate dense graphs that are guaranteed to contain a unique Hamiltonian cycle. This article presents an algorithm for generating arbitrarily large simple graphs containing "unique" Hamiltonian cycles. These graphs can be turned into dense graphs…

  12. FABRICATION OF FINE GRAINED DENSE HAP THROUGH SLIP CASTING ROUTE

    Directory of Open Access Journals (Sweden)

    HOWA BEGAM

    2011-02-01

    Full Text Available The purpose of this study is to synthesize nano-grained Calcium Hydroxyapatite (HAp through slip casting technique. For this, hydroxyapatite powders were synthesized using two methods, wet chemical method and Ammoniacal method. The as-prepared powders and calcined powders were characterized using XRD, FTIR, to study the phases of the powders. The hydroxyapatite powder calcined at 1000°C for 2hr was used to prepare 50 vol% slurry using DN40 (sodium olyacrylate as dispersing agent. After slip casting, the green bodies were sintered at different temperatures, 1100, 1200, 1250 and 1300°C with 2hr soaking time. The sintered dense samples were characterized for physical and mechanical behavior.Dense HaP samples were obtained at 1250C.

  13. Mutual diffusion occurring at the interface between La₀.₆Sr₀.₄Co₀.₈Fe₀.₂O₃ cathode and Gd-doped ceria electrolyte during IT-SOFC cell preparation.

    Science.gov (United States)

    Li, Zhi-Peng; Toshiyuki, Mori; Auchterlonie, Graeme John; Zou, Jin; John, Drennan

    2011-07-01

    The microstructure and local chemistry of the interface between the screen-printed La(0.6)Sr(0.4)Co(0.8)Fe(0.2)O(3) (LSCF) thin film cathode and Gd-doped ceria (GDC) electrolyte substrate have been investigated. Elemental distribution analyses, by energy-dispersive X-ray spectroscopy operated in scanning transmission electron microscopy (STEM) mode, illustrate that all constituent elements in GDC and LSCF mutually diffuse across the LSCF/GDC interface, with equal diffusion length. This leads to the formation of mutual diffusion zones at the LSCF/GDC interfaces, with the resultant mixture of diffusing ions being associated with specific valence state changes, as verified by STEM electron energy loss spectroscopy analyses. Moreover, this mutual diffusion can result in microstructural changes, where superstructure formation is accompanied by enhancement of oxygen vacancy ordering at this region. Such mutual diffusion and associated microstructure evolution is considered to be detrimental to fuel cell efficiency and should be suppressed by lowering cell fabrication temperatures.

  14. High-Performance Protonic Ceramic Fuel Cells with Thin-Film Yttrium-Doped Barium Cerate-Zirconate Electrolytes on Compositionally Gradient Anodes.

    Science.gov (United States)

    Bae, Kiho; Lee, Sewook; Jang, Dong Young; Kim, Hyun Joong; Lee, Hunhyeong; Shin, Dongwook; Son, Ji-Won; Shim, Joon Hyung

    2016-04-13

    In this study, we used a compositionally gradient anode functional layer (AFL) consisting of Ni-BaCe(0.5)Zr(0.35)Y(0.15)O(3-δ) (BCZY) with increasing BCZY contents toward the electrolyte-anode interface for high-performance protonic ceramic fuel cells. It is identified that conventional homogeneous AFLs fail to stably accommodate a thin film of BCZY electrolyte. In contrast, a dense 2 μm thick BCZY electrolyte was successfully deposited onto the proposed gradient AFL with improved adhesion. A fuel cell containing this thin electrolyte showed a promising maximum peak power density of 635 mW cm(-2) at 600 °C, with an open-circuit voltage of over 1 V. Impedance analysis confirmed that minimizing the electrolyte thickness is essential for achieving a high power output, suggesting that the anode structure is important in stably accommodating thin electrolytes.

  15. Ionogel Electrolytes through Sol-Gel Processing

    Science.gov (United States)

    Horowitz, Ariel I.

    Electrical energy needs have intensified due to the ubiquity of personal electronics, the decarbonization of energy services through electrification, and the use of intermittent renewable energy sources. Despite developments in mechanical and thermal methods, electrochemical technologies are the most convenient and effective means of storing electrical energy. These technologies include both electrochemical cells, commonly called batteries, and electrochemical double-layer capacitors, or "supercapacitors", which store energy electrostatically. Both device types require an ion-conducting electrolyte. Current devices use solutions of complex salts in organic solvents, leading to both toxicity and flammability concerns. These drawbacks can be avoided by replacing conventional electrolytes with room-temperature molten salts, known as ionic liquids (ILs). ILs are non-volatile, non-flammable, and offer high conductivity and good electrochemical stability. Device mass can be reduced by combining ILs with a solid scaffold material to form an "ionogel," further improving performance metrics. In this work, sol-gel chemistry is explored as a means of forming ionogel electrolytes. Sol-gel chemistry is a solution-based, industrially-relevant, well-studied technique by which solids such as silica can be formed in situ. Previous works used a simple acid-catalyzed sol-gel reaction to create brittle, glassy ionogels. Here, both the range of products that can be accomplished through sol-gel processing and the understanding of interactions between ILs and the sol-gel reaction network are greatly expanded. This work introduces novel ionogel materials, including soft and compliant silica-supported ionogels and PDMS-supported ionogels. The impacts of the reactive formulation, IL identity, and casting time are detailed. It is demonstrated that variations in formulation can lead to rapid gelation and open pore structures in the silica scaffold or slow gelation and more dense silica

  16. Probing Cold Dense Nuclear Matter

    Energy Technology Data Exchange (ETDEWEB)

    Subedi, Ramesh; Shneor, R.; Monaghan, Peter; Anderson, Bryon; Aniol, Konrad; Annand, John; Arrington, John; Benaoum, Hachemi; Benmokhtar, Fatiha; Bertozzi, William; Boeglin, Werner; Chen, Jian-Ping; Choi, Seonho; Cisbani, Evaristo; Craver, Brandon; Frullani, Salvatore; Garibaldi, Franco; Gilad, Shalev; Gilman, Ronald; Glamazdin, Oleksandr; Hansen, Jens-Ole; Higinbotham, Douglas; Holmstrom, Timothy; Ibrahim, Hassan; Igarashi, Ryuichi; De Jager, Cornelis; Jans, Eddy; Jiang, Xiaodong; Kaufman, Lisa; Kelleher, Aidan; Kolarkar, Ameya; Kumbartzki, Gerfried; LeRose, John; Lindgren, Richard; Liyanage, Nilanga; Margaziotis, Demetrius; Markowitz, Pete; Marrone, Stefano; Mazouz, Malek; Meekins, David; Michaels, Robert; Moffit, Bryan; Perdrisat, Charles; Piasetzky, Eliazer; Potokar, Milan; Punjabi, Vina; Qiang, Yi; Reinhold, Joerg; Ron, Guy; Rosner, Guenther; Saha, Arunava; Sawatzky, Bradley; Shahinyan, Albert; Sirca, Simon; Slifer, Karl; Solvignon, Patricia; Sulkosky, Vince; Sulkosky, Vincent; Sulkosky, Vince; Sulkosky, Vincent; Urciuoli, Guido; Voutier, Eric; Watson, John; Weinstein, Lawrence; Wojtsekhowski, Bogdan; Wood, Stephen; Zheng, Xiaochao; Zhu, Lingyan

    2008-06-01

    The protons and neutrons in a nucleus can form strongly correlated nucleon pairs. Scattering experiments, in which a proton is knocked out of the nucleus with high-momentum transfer and high missing momentum, show that in carbon-12 the neutron-proton pairs are nearly 20 times as prevalent as proton-proton pairs and, by inference, neutron-neutron pairs. This difference between the types of pairs is due to the nature of the strong force and has implications for understanding cold dense nuclear systems such as neutron stars.

  17. Probing Cold Dense Nuclear Matter

    CERN Document Server

    Subedi, R; Monaghan, P; Anderson, B D; Aniol, K; Annand, J; Arrington, J; Benaoum, H; Benmokhtar, F; Bertozzi, W; Boeglin, W; Chen, J -P; Choi, Seonho; Cisbani, E; Craver, B; Frullani, S; Garibaldi, F; Gilad, S; Gilman, R; Glamazdin, O; Hansen, J -O; Higinbotham, D W; Holmstrom, T; Ibrahim, H; Igarashi, R; De Jager, C W; Jans, E; Jiang, X; Kaufman, L; Kelleher, A; Kolarkar, A; Kumbartzki, G; LeRose, J J; Lindgren, R; Liyanage, N; Margaziotis, D J; Markowitz, P; Marrone, S; Mazouz, M; Meekins, D; Michaels, R; Moffit, B; Perdrisat, C F; Piasetzky, E; Potokar, M; Punjabi, V; Qiang, Y; Reinhold, J; Ron, G; Rosner, G; Saha, A; Sawatzky, B; Shahinyan, A; Širca, S; Slifer, K; Solvignon, P; Sulkosky, V; Urciuoli, G; Voutier, E; Watson, J W; Weinstein, L B; Wojtsekhowski, B; Wood, S; Zheng, X -C; Zhu, L; 10.1126/science.1156675

    2009-01-01

    The protons and neutrons in a nucleus can form strongly correlated nucleon pairs. Scattering experiments, where a proton is knocked-out of the nucleus with high momentum transfer and high missing momentum, show that in 12C the neutron-proton pairs are nearly twenty times as prevalent as proton-proton pairs and, by inference, neutron-neutron pairs. This difference between the types of pairs is due to the nature of the strong force and has implications for understanding cold dense nuclear systems such as neutron stars.

  18. Dilatons in Dense Baryonic Matter

    CERN Document Server

    Lee, Hyun Kyu

    2013-01-01

    We discuss the role of dilaton, which is supposed to be representing a special feature of scale symmetry of QCD, trace anomaly, in dense baryonic matter. The idea that the scale symmetry breaking of QCD is responsible for the spontaneous breaking of chiral symmetry is presented along the similar spirit of Freund-Nambu model. The incorporation of dilaton field in the hidden local symmetric parity doublet model is briefly sketched with the possible role of dilaton at high density baryonic matter, the emergence of linear sigma model in dilaton limit.

  19. Fluid and Electrolyte Nutrition

    Science.gov (United States)

    Lane, Helen W.; Smith, Scott M.; Leach, Carolyn S.; Rice, Barbara L.

    1999-01-01

    Studies of fluid and electrolyte homeostasis have been completed since the early human space flight programs, with comprehensive research completed on the Spacelab Life Sciences missions SLS-1 and SLS-2 flights, and more recently on the Mir 18 mission. This work documented the known shifts in fluids, the decrease in total blood volume, and indications of reduced thirst. Data from these flights was used to evaluate the nutritional needs for water, sodium, and potassium. Interpretations of the data are confounded by the inadequate energy intakes routinely observed during space flight. This in turn results in reduced fluid intake, as food provides approximately 70% water intake. Subsequently, body weight, lean body mass, total body water, and total body potassium may decrease. Given these issues, there is evidence to support a minimum required water intake of 2 L per day. Data from previous Shuttle flights indicated that water intake is 2285 +/- 715 ml/day (mean +/- SD, n=26). There are no indications that sodium intake or homeostasis is compromised during space flight. The normal or low aldosterone and urinary sodium levels suggest adequate sodium intake (4047 +/- 902 mg/day, n=26). Because excessive sodium intake is associated with hypercalciuria, the recommended maximum amount of sodium intake during flight is 3500 mg/day (i.e., similar to the Recommended Dietary Allowance, RDA). Potassium metabolism appears to be more complex. Data indicate loss of body potassium related to muscle atrophy and low dietary intake (2407 +/- 548 mg/day, n=26). Although possibly related to measurement error, the elevations in blood potassium suggest alterations in potassium homeostasis. The space RDA for minimum potassium intake is 3500 mg/day. With the documented inadequate intakes, efforts are being made to increase dietary consumption of potassium.

  20. A general approach toward enhancement of pseudocapacitive performance of conducting polymers by redox-active electrolytes

    KAUST Repository

    Chen, Wei

    2014-12-01

    A general approach is demonstrated where the pseudocapacitive performance of different conducting polymers is enhanced in redox-active electrolytes. The concept is demonstrated using several electroactive conducting polymers, including polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene). As compared to conventional electrolytes, the redox-active electrolytes, prepared by simply adding a redox mediator to the conventional electrolyte, can significantly improve the energy storage capacity of pseudocapacitors with different conducting polymers. The results show that the specific capacitance of conducting polymer based pseudocapacitors can be increased by a factor of two by utilization of the redox-active electrolytes. In fact, this approach gives some of the highest reported specific capacitance values for electroactive conducting polymers. Moreover, our findings present a general and effective approach for the enhancement of energy storage performance of pseudocapacitors using a variety of polymeric electrode materials. © 2014 Elsevier B.V. All rights reserved.

  1. Capacitance of porous carbon electrode in mixed salt non-aqueous electrolytes

    Science.gov (United States)

    Egashira, Minato; Sawada, Nozomu; Ueda, Kazuteru; Yoshimoto, Nobuko; Morita, Masayuki

    Capacitances of a porous carbon electrode in non-aqueous electrolytes containing tetraethylamonium tetrafluoroborate (TEABF 4) and a lithium salt with various compositions have been investigated for the potential use in electric double layer capacitor. In the electrolyte prepared by dissolving TEABF 4 and LiBF 4 into the mixed solvent of ethylene carbonate (EC) with diethyl carbonate (DMC), an activated carbon fiber (ACF) electrode exhibits a larger capacitance than in TEABF 4 single salt electrolyte on cyclic voltammograms. The symmetrical capacitor cell containing the LiBF 4-TEABF 4 mixed salt electrolyte also exhibits larger capacitance on a constant-current test compared with that containing the TEABF 4 single salt electrolyte, while the capacitance degradation is observable for this cell at a significant extent, while the test under controlled potential of the ACF electrode to -0.2 to 1.0 V vs. Ag provides somewhat stable capacitance over 30 cycles.

  2. Conductivity through Polymer Electrolytes and Its Implications in Lithium-Ion Batteries: Real-World Application of Periodic Trends

    Science.gov (United States)

    Compton, Owen C.; Egan, Martin; Kanakaraj, Rupa; Higgins, Thomas B.; Nguyen, SonBinh T.

    2012-01-01

    Periodic conductivity trends are placed in the scope of lithium-ion batteries, where increases in the ionic radii of salt components affect the conductivity of a poly(ethyleneoxide)-based polymer electrolyte. Numerous electrolytes containing varying concentrations and types of metal salts are prepared and evaluated in either one or two laboratory…

  3. Conductivity through Polymer Electrolytes and Its Implications in Lithium-Ion Batteries: Real-World Application of Periodic Trends

    Science.gov (United States)

    Compton, Owen C.; Egan, Martin; Kanakaraj, Rupa; Higgins, Thomas B.; Nguyen, SonBinh T.

    2012-01-01

    Periodic conductivity trends are placed in the scope of lithium-ion batteries, where increases in the ionic radii of salt components affect the conductivity of a poly(ethyleneoxide)-based polymer electrolyte. Numerous electrolytes containing varying concentrations and types of metal salts are prepared and evaluated in either one or two laboratory…

  4. Computational Exploration of the Li-Electrode|Electrolyte Interface in the Presence of a Nanometer Thick Solid-Electrolyte Interphase Layer.

    Science.gov (United States)

    Li, Yunsong; Leung, Kevin; Qi, Yue

    2016-10-18

    A nanometer thick passivation layer will spontaneously form on Li-metal in battery applications due to electrolyte reduction reactions. This passivation layer in rechargeable batteries must have "selective" transport properties: blocking electrons from attacking the electrolytes, while allowing Li(+) ion to pass through so the electrochemical reactions can continue. The classical description of the electrochemical reaction, Li(+) + e → Li(0), occurring at the Li-metal|electrolyte interface is now complicated by the passivation layer and will reply on the coupling of electronic and ionic degrees of freedom in the layer. This passivation layer is called "solid electrolyte interphase (SEI)" and is considered as "the most important but the least understood in rechargeable Li-ion batteries," partly due to the lack of understanding of its structure-property relationship. Predictive modeling, starting from the ab initio level, becomes an important tool to understand the nanoscale processes and materials properties governing the interfacial charge transfer reaction at the Li-metal|SEI|electrolyte interface. Here, we demonstrate pristine Li-metal surfaces indeed dissolve in organic carbonate electrolytes without the SEI layer. Based on joint modeling and experimental results, we point out that the well-known two-layer structure of SEI also exhibits two different Li(+) ion transport mechanisms. The SEI has a porous (organic) outer layer permeable to both Li(+) and anions (dissolved in electrolyte), and a dense (inorganic) inner layer facilitate only Li(+) transport. This two-layer/two-mechanism diffusion model suggests only the dense inorganic layer is effective at protecting Li-metal in electrolytes. This model suggests a strategy to deconvolute the structure-property relationships of the SEI by analyzing an idealized SEI composed of major components, such as Li2CO3, LiF, Li2O, and their mixtures. After sorting out the Li(+) ion diffusion carriers and their diffusion

  5. Dense protective coatings, methods for their preparation and coated articles

    Energy Technology Data Exchange (ETDEWEB)

    Tulyani, Sonia; Bhatia, Tania; Smeggil, John G.

    2015-12-29

    A method for depositing a protective coating on a complex shaped substrate includes the steps of: (1) dipping a complex shaped substrate into a slurry to form a base coat thereon, the slurry comprising an aqueous solution, at least one refractory metal oxide, and at least one transient fluid additive present in an amount of about 0.1 percent to 10 percent by weight of the slurry; (2) curing the dipped substrate; (3) dipping the substrate into a precursor solution to form a top barrier coat thereon; and (4) heat treating the dipped, cured substrate to form a protective coating.

  6. ELECTROLYTIC MEMBRANE DIALYSIS FOR TREATING WASTEWATER STREAMS

    Energy Technology Data Exchange (ETDEWEB)

    Ronald C. Timpe

    2000-04-01

    This project will determine whether electrolytic dialysis has promise in the separation of charged particles in an aqueous solution. The ability to selectively move ions from one aqueous solution to another through a semipermeable membrane will be studied as a function of emf, amperage, and particle electrical charge. The ions selected for the study are Cl{sup -} and SO{sub 4}{sup 2-}. These ions are of particular interest because of their electrical conduction properties in aqueous solution resulting with their association with the corrosive action of metals. The studies will be performed with commercial membranes on solutions prepared in the laboratory from reagent salts. pH adjustments will be made with dilute reagent acid and base. Specific objectives of the project include testing a selected membrane currently available for electrolytic dialysis, membrane resistance to extreme pH conditions, the effectiveness of separating a mixture of two ions selected on the basis of size, the efficiency of the membranes in separating chloride (Cl{sup 1-}) from sulfate (SO{sub 4}{sup 2-}), and separation efficiency as a function of electromotive force (emf).

  7. Polydioxolane Polymer Electrolyte.

    Science.gov (United States)

    1986-10-18

    similar to those above were prepared and held tinder2. 28 3. 32 34 % vacuum for I hour, the condutivities Observed were the sameasPtnil()vLirf ’The... thermal stability Indicated by -. the reproducibility of conductivities remeasured at lower tempp- eratures, As the PE Is heated It appears to soften at...600C with ~- melting occurring In the range 120-1 300C. At this temperature 6. discoloration occurs. presummably due to the. thermal Instability of

  8. Anion exchange polymer electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yu Seung; Kim, Dae Sik; Lee, Kwan-Soo

    2013-07-23

    Solid anion exchange polymer electrolytes and compositions comprising chemical compounds comprising a polymeric core, a spacer A, and a guanidine base, wherein said chemical compound is uniformly dispersed in a suitable solvent and has the structure: ##STR00001## wherein: i) A is a spacer having the structure O, S, SO.sub.2, --NH--, --N(CH.sub.2).sub.n, wherein n=1-10, --(CH.sub.2).sub.n--CH.sub.3--, wherein n=1-10, SO.sub.2-Ph, CO-Ph, ##STR00002## wherein R.sub.5, R.sub.6, R.sub.7 and R.sub.8 each are independently --H, --NH.sub.2, F, Cl, Br, CN, or a C.sub.1-C.sub.6 alkyl group, or any combination of thereof; ii) R.sub.9, R.sub.10, R.sub.11, R.sub.12, or R.sub.13 each independently are --H, --CH.sub.3, --NH.sub.2, --NO, --CH.sub.nCH.sub.3 where n=1-6, HC.dbd.O--, NH.sub.2C.dbd.O--, --CH.sub.nCOOH where n=1-6, --(CH.sub.2).sub.n--C(NH.sub.2)--COOH where n=1-6, --CH--(COOH)--CH.sub.2--COOH, --CH.sub.2--CH(O--CH.sub.2CH.sub.3).sub.2, --(C.dbd.S)--NH.sub.2, --(C.dbd.NH)--N--(CH.sub.2).sub.nCH.sub.3, where n=0-6, --NH--(C.dbd.S)--SH, --CH.sub.2--(C.dbd.O)--O--C(CH.sub.3).sub.3, --O--(CH.sub.2).sub.n--CH--(NH.sub.2)--COOH, where n=1-6, --(CH.sub.2).sub.n--CH.dbd.CH wherein n=1-6, --(CH.sub.2).sub.n--CH--CN wherein n=1-6, an aromatic group such as a phenyl, benzyl, phenoxy, methylbenzyl, nitrogen-substituted benzyl or phenyl groups, a halide, or halide-substituted methyl groups; and iii) wherein the composition is suitable for use in a membrane electrode assembly.

  9. Influence of potassium pyrophosphate in electrolyte on coated layer of AZ91 Mg alloy formed by plasma electrolytic oxidation

    Institute of Scientific and Technical Information of China (English)

    Jin-Young CHO; Duck-Young HWANG; Dong-Heon LEE; Bongyoung YOO; Dong-Hyuk SHIN

    2009-01-01

    The effect of potassium pyrophosphate in the electrolyte on plasma electrolytic oxidation (PEO) process for AZ91 Mg alloy was investigated. The morphologies and chemical compositions of the coating layer on the AZ91 Mg alloy were evaluated and corrosion resistance was also estimated by potentiodynamic polarization analysis. The coating layer on AZ91 Mg alloy coated from the Bath 2 containing 0.03 mol/L of potassium pyrophosphate for 360 s exhibited considerably dense structure and contained 11%-18% (mass fraction) of phosphorous. The higher content of phosphorous of coating layer coated from Bath 2 could be detected at the bottom of oxide layer, which strongly implied that the phosphorous ion might be concentrated at the barrier layer. Corrosion potential of coating layer of AZ91 Mg alloy increased and corrosion current density decreased with increasing the concentration of potassium pyrophosphate. The polarization resistance (Rp) of coating layer of AZ91 Mg alloy coated from Bath 2 was 4.65×107 Ω/cm2, which was higher than that (Rp=3.56×104 Ω/cm2) of the sample coated from electrolyte without potassium pyrophosphate. The coating layer coated from Bath 2 containing 0.03 mol/L potassium pyrophosphate exhibited the best corrosion resistance.

  10. Viscoelastic behavior of dense microemulsions

    Science.gov (United States)

    Cametti, C.; Codastefano, P.; D'arrigo, G.; Tartaglia, P.; Rouch, J.; Chen, S. H.

    1990-09-01

    We have performed extensive measurements of shear viscosity, ultrasonic absorption, and sound velocity in a ternary system consisting of water-decane-sodium di(2-ethylhexyl)sulfo- succinate(AOT), in the one-phase region where it forms a water-in-oil microemulsion. We observe a rapid increase of the static shear viscosity in the dense microemulsion region. Correspondingly the sound absorption shows unambiguous evidence of a viscoelastic behavior. The absorption data for various volume fractions and temperatures can be reduced to a universal curve by scaling both the absorption and the frequency by the measured static shear viscosity. The sound absorption can be interpreted as coming from the high-frequency tail of the viscoelastic relaxation, describable by a Cole-Cole relaxation formula with unusually small elastic moduli.

  11. Neutrino Oscillations in Dense Matter

    Science.gov (United States)

    Lobanov, A. E.

    2017-03-01

    A modification of the electroweak theory, where the fermions with the same electroweak quantum numbers are combined in multiplets and are treated as different quantum states of a single particle, is proposed. In this model, mixing and oscillations of particles arise as a direct consequence of the general principles of quantum field theory. The developed approach enables one to calculate the probabilities of the processes taking place in the detector at long distances from the particle source. Calculations of higher-order processes, including computation of the contributions due to radiative corrections, can be performed in the framework of the perturbation theory using the regular diagram technique. As a result, the analog to the Dirac-Schwinger equation of quantum electrodynamics describing neutrino oscillations and its spin rotation in dense matter can be obtained.

  12. DPIS for warm dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, K.; Kanesue, T.; Horioka, K.; Okamura, M.

    2010-05-23

    Warm Dense Matter (WDM) offers an challenging problem because WDM, which is beyond ideal plasma, is in a low temperature and high density state with partially degenerate electrons and coupled ions. WDM is a common state of matter in astrophysical objects such as cores of giant planets and white dwarfs. The WDM studies require large energy deposition into a small target volume in a shorter time than the hydrodynamical time and need uniformity across the full thickness of the target. Since moderate energy ion beams ({approx} 0.3 MeV/u) can be useful tool for WDM physics, we propose WDM generation using Direct Plasma Injection Scheme (DPIS). In the DPIS, laser ion source is connected to the Radio Frequency Quadrupole (RFQ) linear accelerator directly without the beam transport line. DPIS with a realistic final focus and a linear accelerator can produce WDM.

  13. Polymer electrolytes composed of lithium tetrakis(pentafluorobenzenethiolato) borate and poly(fluoroalkylcarbon)s

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, Takahiro; Konno, Akinori; Fujinami, Tatsuo [Department of Materials Science and Chemical Engineering, Faculty of Engineering, Shizuoka University, 3-5-1, Johoku, Hamamatsu 432-8561 (Japan)

    2005-08-26

    Lithium ion conducting polymer electrolytes were prepared by mixing insoluble lithium tetrakis(pentafluorobenzenethiolato) borate (LiTPSB) with poly(vinylidene fluoride) (PVDF) or poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP). Their films were prepared by hot pressing and are investigated for ionic conductivity and thermal properties. LiTPSB is insoluble in PVDF. Ionic conductivity was largely dependent on the salt content for LiTPSB-PVDF composite polymer electrolytes, and exhibited higher ionic conductivity than homogeneous LiTFSI-PVDF based polymer electrolytes. Melting point and crystallinity of PVDF were independent on LiTPSB content, resulting in no difference for melting point and crystallinity between pure PVDF and LiTPSB-PVDF. Ionic conductivity was effectively improved by incorporation of 18-crown-6 or kryptofix222 for LiTPSB-PVDF based polymer electrolytes. (author)

  14. Semiconductor electrolyte photovoltaic energy converter

    Science.gov (United States)

    Anderson, W. W.; Anderson, L. B.

    1975-01-01

    Feasibility and practicality of a solar cell consisting of a semiconductor surface in contact with an electrolyte are evaluated. Basic components and processes are detailed for photovoltaic energy conversion at the surface of an n-type semiconductor in contact with an electrolyte which is oxidizing to conduction band electrons. Characteristics of single crystal CdS, GaAs, CdSe, CdTe and thin film CdS in contact with aqueous and methanol based electrolytes are studied and open circuit voltages are measured from Mott-Schottky plots and open circuit photo voltages. Quantum efficiencies for short circuit photo currents of a CdS crystal and a 20 micrometer film are shown together with electrical and photovoltaic properties. Highest photon irradiances are observed with the GaAs cell.

  15. Diabetes mellitus and electrolyte disorders

    Science.gov (United States)

    Liamis, George; Liberopoulos, Evangelos; Barkas, Fotios; Elisaf, Moses

    2014-01-01

    Diabetic patients frequently develop a constellation of electrolyte disorders. These disturbances are particularly common in decompensated diabetics, especially in the context of diabetic ketoacidosis or nonketotic hyperglycemic hyperosmolar syndrome. These patients are markedly potassium-, magnesium- and phosphate-depleted. Diabetes mellitus (DM) is linked to both hypo- and hyper-natremia reflecting the coexistence of hyperglycemia-related mechanisms, which tend to change serum sodium to opposite directions. The most important causal factor of chronic hyperkalemia in diabetic individuals is the syndrome of hyporeninemic hypoaldosteronism. Impaired renal function, potassium-sparing drugs, hypertonicity and insulin deficiency are also involved in the development of hyperkalemia. This article provides an overview of the electrolyte disturbances occurring in DM and describes the underlying mechanisms. This insight should pave the way for pathophysiology-directed therapy, thus contributing to the avoidance of the several deleterious effects associated with electrolyte disorders and their treatment. PMID:25325058

  16. Preparation and characterization of PEO based Li1.5Al0.5Ge1.5(PO4)3 solid composite electrolyte%PEO基Li1.5Al0.5Ge1.5(PO4)3固体复合电解质的制备

    Institute of Scientific and Technical Information of China (English)

    余涛; 谢凯; 韩喻; 王珲

    2015-01-01

    以聚环氧乙烷(PEO)为黏结剂,离子导电性的 Li1.5Al0.5Ge1.5(PO4)3(LAGP)为主相,乙腈为溶剂,按照EO/Li,摩尔比为13,变化LiN(CF3SO2)2(LiTFSI)中Li+与LAGP中Li+的比例,通过溶液浇注法制备得到LAGP-PEO(LiTFSI)固体复合电解质。用X射线衍射、扫描电镜(SEM)和电化学阻抗(EIS)等方法对固体复合电解质的形貌、结构和电导率进行表征。结果表明,LAGP 可与 PEO(LiTFSI)部分络合并均匀分散于PEO(LITFSI)内,整个体系内存有三个主体相,即PEO(LiTFSI)的复合相、LAGP晶相以及PEO与两种锂盐的过渡相。通过阻抗谱图发现,当质量比w(LAGP)∶w(PEO)=6∶4时,LAGP-PEO(LiTFSI)固体复合电解质具有最高的室温电导率,为2.68×10−5S/cm,在333 K时,达到1.86×10−4S/cm,接近LAGP的电导率水平。这说明固体复合电解质中加入LAGP即降低了PEO的结晶度,LAGP自身的电导率也有一定贡献。%PEO-based solid composite electrolyte with the fast ion conductor LAGP(Li1.5Al0.5Ge1.5(PO4)3) as a main ionic conductive component and PEO as the binder were prepared by the solution casting method with fixedn(EO)/n(Li)=13, but varying ratio of LiTFSI to LAGP. The structure and morphology of the solid composite electrolyte were characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM). The conductivity of LAGP-PEO(LiTFSI) electrolyte was analyzed by electrical impedance spectroscopy (EIS). The results show that LAGP is partially complexed with PEO(LiTFSI) and homogeneously distributed in PEO(LiTFSI). Three phases are present, a pure crystalline LAGP phase, amorphous PEO(LiTFSI) phase and a transition phase of the LAGP particles and amorphous PEO(LiTFSI). Withw(LAGP)∶w(PEO)=6∶4, the optimal ionic conductivity for LAGP-PEO(LiTFSI) solid composite electrolyte is 2.68×10−5S/cm at room temperature and 1.86×10−4S/cm at 373 K which is close to the LAGP. It means that the LAGP

  17. Structural and Electrochemical Analysis of PMMA Based Gel Electrolyte Membranes

    Directory of Open Access Journals (Sweden)

    Chithra M. Mathew

    2015-01-01

    Full Text Available New gel polymer electrolytes containing poly(vinylidene chloride-co-acrylonitrile and poly(methyl methacrylate are prepared by solution casting method. With the addition of 60 wt.% of EC to PVdC-AN/PMMA blend, ionic conductivity value 0.398×10-6 S cm−1 has been achieved. XRD and FT-IR studies have been conducted to investigate the structure and complexation in the polymer gel electrolytes. The FT-IR spectra show that the functional groups C=O and C≡N play major role in ion conduction. Thermal stability of the prepared membranes is found to be about 180°C.

  18. High efficiency solid state dye sensitized solar cells with graphene-polyethylene oxide composite electrolytes.

    Science.gov (United States)

    Akhtar, M Shaheer; Kwon, Soonji; Stadler, Florian J; Yang, O Bong

    2013-06-21

    Novel and highly effective composite electrolytes were prepared by combining the two dimensional graphene (Gra) and polyethylene oxide (PEO) for the solid electrolyte of dye sensitized solar cells (DSSCs). Gra sheets were uniformly coated by the polymer layer through the ester carboxylate bonding between oxygenated species on Gra sheets and PEO. The Gra-PEO composite electrolyte showed the large scale generation of iodide ions in a redox couple. From rheological analysis, the decrease in viscosity after the addition of LiI and I2 in the Gra-PEO electrolyte might be explained by the dipolar interactions being severely disrupted by the ionic interactions of Li(+), I(-), and I3(-) ions. A composite electrolyte with 0.5 wt% Gra presented a higher ionic conductivity (3.32 mS cm(-1)) than those of PEO and other composite electrolytes at room temperature. A high overall conversion efficiency (∼5.23%) with a very high short circuit current (JSC) of 18.32 mA cm(-2), open circuit voltage (VOC) of 0.592 V and fill factor (FF) of 0.48 was achieved in DSSCs fabricated with the 0.5 wt% Gra-PEO composite electrolyte. This enhanced photovoltaic performance might be attributed to the large scale formation of iodide ions in the redox electrolyte and the relatively high ionic conductivity.

  19. Lithium bis(fluorosulfonyl)imide based low ethylene carbonate content electrolyte with unusual solvation state

    Science.gov (United States)

    Uchida, Satoshi; Ishikawa, Masashi

    2017-08-01

    We prepared a lithium bis(fluorosulfonyl)imide (LiFSI)-based low ethylene carbonate (EC) content electrolyte as a new electrolyte. LiFSI enough dissociates in mixed solvents containing only a small amount of EC and the LiFSI-based low EC content electrolyte shows a high ionic conductivity comparable to that of a conventional LiPF6-based high EC content electrolyte. In addition, the LiFSI-based low EC content electrolyte has an unusual solvation state of Li ion and we consider that the desolvation process from Li ion in our new electrolyte system is different from that in the conventional high EC content systems. A graphite half-cell assembled with our new electrolyte shows a quite low Li ion transfer resistance and outstanding charge and discharge rate performance compared to the conventional high EC content systems. A graphite/LiNi1/3Mn1/3Co1/3O2 cell assembled with our new electrolyte also shows superior charge and discharge rate performance and excellent long cycle stability.

  20. Lithium Polymer Electrolytes and Solid State NMR

    Science.gov (United States)

    Berkeley, Emily R.

    2004-01-01

    Research is being done at the Glenn Research Center (GRC) developing new kinds of batteries that do not depend on a solution. Currently, batteries use liquid electrolytes containing lithium. Problems with the liquid electrolyte are (1) solvents used can leak out of the battery, so larger, more restrictive, packages have to be made, inhibiting the diversity of application and decreasing the power density; (2) the liquid is incompatible with the lithium metal anode, so alternative, less efficient, anodes are required. The Materials Department at GRC has been working to synthesize polymer electrolytes that can replace the liquid electrolytes. The advantages are that polymer electrolytes do not have the potential to leak so they can be used for a variety of tasks, small or large, including in the space rover or in space suits. The polymers generated by Dr. Mary Ann Meador's group are in the form of rod -coil structures. The rod aspect gives the polymer structural integrity, while the coil makes it flexible. Lithium ions are used in these polymers because of their high mobility. The coils have repeating units of oxygen which stabilize the positive lithium by donating electron density. This aids in the movement of the lithium within the polymer, which contributes to higher conductivity. In addition to conductivity testing, these polymers are characterized using DSC, TGA, FTIR, and solid state NMR. Solid state NMR is used in classifying materials that are not soluble in solvents, such as polymers. The NMR spins the sample at a magic angle (54.7') allowing the significant peaks to emerge. Although solid state NMR is a helpful technique in determining bonding, the process of preparing the sample and tuning it properly are intricate jobs that require patience; especially since each run takes about six hours. The NMR allows for the advancement of polymer synthesis by showing if the expected results were achieved. Using the NMR, in addition to looking at polymers, allows for

  1. Optimization of hybrid polymer electrolytes with the effect of lithium salt concentration in PEO/PVdF-HFP blends

    Energy Technology Data Exchange (ETDEWEB)

    Pradeepa, P.; Edwin raj, S.; Sowmya, G.; Kalaiselvimary, J.; Ramesh Prabhu, M., E-mail: mkram83@gmail.com

    2016-03-15

    Highlights: • Polymer blends based on PVdF-HFP/PEO were prepared for Li-ion battery applications. • Structural and electrochemical studies were carried out on prepared electrolytes. • The electrolytes can be used as electrolyte in the possible device fabrications. - Abstract: Poly(ethylene oxide) (PEO) 6.25 wt%/poly(vinylidene fluoride-co-hexafluoropropylene) [P(VdF-HFP)] 18.75 wt% blend based electrolyte films containing different concentrations (2–10) wt% of lithium salt were prepared. The miscibility studies have been performed by using X-ray diffraction and Fourier transform infrared spectroscopy. The role of interaction between polymer hosts on conductivity is discussed using the results of a.c. impedance studies. A room temperature conductivity of 2.3912 × 10{sup −4} S cm{sup −1} has been obtained for PEO (6.25)–PVdF-HFP (18.75)–LiClO{sub 4} (8)–PC (67) polymer complex. The temperature dependence of the conductivity of polymer electrolyte seems to obey VTF relation. Electrochemical stability (3.3 V) was observed in the prepared polymer electrolyte. Reduction process and oxidation process of the prepared electrolyte system have also been evaluated by means of cyclic voltammetry. Thermogravimetric analysis results indicate thermal stability of PEO/PVdF-HFP lithium salt complexes. Roughness parameter of the sample having maximum ionic conductivity was studied by AFM. The morphology of the polymer complex is investigated by using SEM.

  2. Ceramic-in-polymer versus polymer-in-ceramic polymeric electrolytes - A novel approach

    Energy Technology Data Exchange (ETDEWEB)

    Syzdek, Jaroslaw [Warsaw University of Technology, Faculty of Chemistry, ul. Noakowskiego 3, 00-664 Warszawa (Poland); Universite de Picardie Jules Verne, Laboratoire de Reactivite et de Chimie des Solides, 33 Rue Saint-Leu, F-80039 Amiens Cedex (France); Armand, Michel [Universite de Picardie Jules Verne, Laboratoire de Reactivite et de Chimie des Solides, 33 Rue Saint-Leu, F-80039 Amiens Cedex (France); Gizowska, Magdalena; Marcinek, Marek; Sasim, Elzbieta; Szafran, Mikolaj; Wieczorek, Wladyslaw [Warsaw University of Technology, Faculty of Chemistry, ul. Noakowskiego 3, 00-664 Warszawa (Poland)

    2009-10-20

    A new type of composites, i.e. polymer-in-ceramic (as opposed to the ''classical'' ceramic-in-polymer approach) was introduced into the field of composite polymeric electrolytes. In this work the preparation of porous ceramic samples based on alumina is designed and their properties are characterised by XRD, porosimetry and SEM. Special setup was developed for the preparation of electrolytes in vacuum/controlled atmosphere conditions and it was used for preparing the composites. The studied systems exhibited excellent mechanical properties, high conductivities and good stability vs. Li metal electrodes under prolonged storage. (author)

  3. Synthesis and Characterization of a Novel Polymer Electrolyte for Lithium-ion Battery

    Institute of Scientific and Technical Information of China (English)

    Yan Ping Liang; Hong Zhu MA; Bo WANG

    2004-01-01

    A novel polymer electrolyte with the formula of Li2B4O7-PVA for lithium-ion battery was synthesized and its ion conductivity and mechanical properties were also tested. It is found that the conductivity of the prepared polymer electrolytes is higher than that of LiClO4/PEO or LiClO4/EC-DMC by two or three orders in magnitude and a large delocalized bond formed in Li2B4O7-PVA lead to transportation of Li ion easier, this electrolyte possesses high thermo-stability and can be used under 200°C.

  4. Study on the Ion Association in PVdF-based Gel Polymer Electrolyte

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Gel polymer electrolytes based on the poly (vinylidene fluoride) (PVdF) and the electrolyte of LiClO4 in propylene carbonate (PC) were prepared by the solution casting technique. The ionic conductivity of the gel electrolytes was concentration of lithium salt. Because of the strong coulombiq attractions, the dissolved salt ions might aggregate into ion pairs and multiple ion aggregates. The analysis of DSC and X-ray diffraction revealed that the ions association occurred at higher concentration of lithium salt.

  5. Solid State Multinuclear Magnetic Resonance Investigation of Electrolyte Decomposition Products on Lithium Ion Electrodes

    Science.gov (United States)

    DeSilva, J .H. S. R.; Udinwe, V.; Sideris, P. J.; Smart, M. C.; Krause, F. C.; Hwang, C.; Smith, K. A.; Greenbaum, S. G.

    2012-01-01

    Solid electrolyte interphase (SEI) formation in lithium ion cells prepared with advanced electrolytes is investigated by solid state multinuclear (7Li, 19F, 31P) magnetic resonance (NMR) measurements of electrode materials harvested from cycled cells subjected to an accelerated aging protocol. The electrolyte composition is varied to include the addition of fluorinated carbonates and triphenyl phosphate (TPP, a flame retardant). In addition to species associated with LiPF6 decomposition, cathode NMR spectra are characterized by the presence of compounds originating from the TPP additive. Substantial amounts of LiF are observed in the anodes as well as compounds originating from the fluorinated carbonates.

  6. Influences of Electrolytes on the Soap-free Emulsion Copolymerization of St-MMA-AA

    Institute of Scientific and Technical Information of China (English)

    Rong Long LI; Cheng You KAN; Yi DU; Ze Ping LI

    2006-01-01

    Monodisperse functional polymer microspheres with different particle size and with clean surface were prepared by batch soap-free emulsion polymerization of styrene, methyl methacrylate and acrylic acid in the presence of salts, and the influences of type and amount of electrolytes on polymerization process and particle morphology were investigated. Results showed that there was a critical concentration for different electrolyte to make polymerization process and the resultant emulsion stable, and the particle size increased with the increase of electrolyte concentration. The effect of metal ions was Ca2+>>K+>Na+>Li+, and the effect of haloids was Br->Cl->F-.

  7. Solid State Multinuclear Magnetic Resonance Investigation of Electrolyte Decomposition Products on Lithium Ion Electrodes

    Science.gov (United States)

    DeSilva, J .H. S. R.; Udinwe, V.; Sideris, P. J.; Smart, M. C.; Krause, F. C.; Hwang, C.; Smith, K. A.; Greenbaum, S. G.

    2012-01-01

    Solid electrolyte interphase (SEI) formation in lithium ion cells prepared with advanced electrolytes is investigated by solid state multinuclear (7Li, 19F, 31P) magnetic resonance (NMR) measurements of electrode materials harvested from cycled cells subjected to an accelerated aging protocol. The electrolyte composition is varied to include the addition of fluorinated carbonates and triphenyl phosphate (TPP, a flame retardant). In addition to species associated with LiPF6 decomposition, cathode NMR spectra are characterized by the presence of compounds originating from the TPP additive. Substantial amounts of LiF are observed in the anodes as well as compounds originating from the fluorinated carbonates.

  8. Solid oxide fuel cell electrolytes produced via very low pressure suspension plasma spray and electrophoretic deposition

    OpenAIRE

    Fleetwood, James D

    2014-01-01

    Solid oxide fuel cells (SOFCs) are a promising element of comprehensive energy policies due to their direct mechanism for converting the oxidization of fuel, such as hydrogen, into electrical energy. Both very low pressure plasma spray and electrophoretic deposition allow working with high melting temperature SOFC suspension based feedstock on complex surfaces, such as in non-planar SOFC designs. Dense, thin electrolytes of ideal composition for SOFCs can be fabricated with each of these proc...

  9. Thermoelectricity in confined liquid electrolytes

    CERN Document Server

    Dietzel, Mathias

    2015-01-01

    The electric field in an extended phase of a liquid electrolyte exposed to a temperature gradient is attributed to different thermophoretic mobilities of the ion species. As shown herein, such Soret-type ion thermodiffusion is not required to induce thermoelectricity even in the simplest electrolyte if it is confined between charged walls. The space charge of the electric double layer leads to selective ion diffusion driven by a temperature-dependent electrophoretic ion mobility, which -for narrow channels- may cause thermo-voltages larger in magnitude than for the classical Soret equilibrium.

  10. Studies on Gel Electrolyte Based on Nitrile-Butadiene Copolymers

    Science.gov (United States)

    1993-06-01

    preparation of a hybrid electrolyte, suitable for solid-polymer batteries. Based on the study of ionic conductivity in the presence of LiBF4 of a...lithium salts in different plasticizers showed the highest conductivity for LiBF4 . Conductivity of LiBF4 in different plasticizers decreases in the order...GLASS TRANSITION 53 TEMPERATURE OF VARIOUS NBR COPOLYMERS WITH AND WITHOUT LiBF4 APPENDIX B: ANOMALY IN THE IONIC 63 CONDUCTIVITY-TEMPERATURE STUDIES

  11. Novel, Solvent-Free, Single Ion-Conducting Polymer Electrolytes

    Science.gov (United States)

    2007-10-31

    the selected polymer electrolyte membrane and a LiFePO4 -based composite cathode film. The latter was prepared by blending the LiFePO4 active...following: charge Li+ + FePO4 + e LiFePO4 [1] discharge to which is associate a maximum...as separator in a Li/ LiFePO4 battery. . 1.Experimental. Calixpyrrole (CP, provided by the University of Warsaw), LiBOB (Libby) and PEO

  12. Effect of cerium addition on microstructure and texture of aluminum foil for electrolytic capacitors

    Institute of Scientific and Technical Information of China (English)

    王海燕; 李文学; 任慧平; 黄丽颖; 王向阳

    2010-01-01

    Anode foil of aluminum electrolytic capacitor,which requires large surface area for high capacitance,were prepared by rolling,annealing and electrochemical etching.Effects of cerium addition on the capacitance of aluminum electrolytic capacitors were investigated.Microstructure of the aluminum foil surface was observed by optical microscopy(OM) and scanning electron microscopy(SEM).Electron back scattered diffraction(EBSD) was also employed to reveal texture evolvement of cold-rolled aluminum foil after ann...

  13. 5G Ultra-Dense Cellular Networks

    OpenAIRE

    Ge, Xiaohu; Tu, Song; Mao, Guoqiang; Wang, Cheng-xiang; Han, Tao

    2015-01-01

    Traditional ultra-dense wireless networks are recommended as a complement for cellular networks and are deployed in partial areas, such as hotspot and indoor scenarios. Based on the massive multiple-input multi-output (MIMO) antennas and the millimeter wavecommunication technologies, the 5G ultra-dense cellular network is proposed to deploy in overall cellular scenarios. Moreover, a distribution network architecture is presented for 5G ultra-dense cellular networks. Furthermore, the backhaul ...

  14. Interference Coordination for Dense Wireless Networks

    DEFF Research Database (Denmark)

    Soret, Beatriz; Pedersen, Klaus I.; Jørgensen, Niels T.K.

    2015-01-01

    The promise of ubiquitous and super-fast connectivity for the upcoming years will be in large part fulfilled by the addition of base stations and spectral aggregation. The resulting very dense networks (DenseNets) will face a number of technical challenges. Among others, the interference emerges ...... simply react to an identified interference problem. As an example, we propose two algorithms to apply time domain and frequency domain small cell interference coordination in a DenseNet....

  15. HOW GOOD IS A DENSE SHOP SCHEDULE?

    Institute of Scientific and Technical Information of China (English)

    陈礴; 俞文(鱼此)

    2001-01-01

    In this paper, we study a class of simple and easy-to-construct shop schedules, known as dense schedules. We present tight bounds on the maximum deviation in makespan of dense flow-shop and job-shop schedules from their optimal ones. For dense open-shop schedules, we do the same for the special case of four machines and thus add a stronger supporting case for proving a standing conjecture.

  16. Breaking Dense Structures: Proving Stability of Densely Structured Hybrid Systems

    Directory of Open Access Journals (Sweden)

    Eike Möhlmann

    2015-06-01

    Full Text Available Abstraction and refinement is widely used in software development. Such techniques are valuable since they allow to handle even more complex systems. One key point is the ability to decompose a large system into subsystems, analyze those subsystems and deduce properties of the larger system. As cyber-physical systems tend to become more and more complex, such techniques become more appealing. In 2009, Oehlerking and Theel presented a (de-composition technique for hybrid systems. This technique is graph-based and constructs a Lyapunov function for hybrid systems having a complex discrete state space. The technique consists of (1 decomposing the underlying graph of the hybrid system into subgraphs, (2 computing multiple local Lyapunov functions for the subgraphs, and finally (3 composing the local Lyapunov functions into a piecewise Lyapunov function. A Lyapunov function can serve multiple purposes, e.g., it certifies stability or termination of a system or allows to construct invariant sets, which in turn may be used to certify safety and security. In this paper, we propose an improvement to the decomposing technique, which relaxes the graph structure before applying the decomposition technique. Our relaxation significantly reduces the connectivity of the graph by exploiting super-dense switching. The relaxation makes the decomposition technique more efficient on one hand and on the other allows to decompose a wider range of graph structures.

  17. Kinetic Simulations of Dense Plasma Focus Breakdown

    Science.gov (United States)

    Schmidt, A.; Higginson, D. P.; Jiang, S.; Link, A.; Povilus, A.; Sears, J.; Bennett, N.; Rose, D. V.; Welch, D. R.

    2015-11-01

    A dense plasma focus (DPF) device is a type of plasma gun that drives current through a set of coaxial electrodes to assemble gas inside the device and then implode that gas on axis to form a Z-pinch. This implosion drives hydrodynamic and kinetic instabilities that generate strong electric fields, which produces a short intense pulse of x-rays, high-energy (>100 keV) electrons and ions, and (in deuterium gas) neutrons. A strong factor in pinch performance is the initial breakdown and ionization of the gas along the insulator surface separating the two electrodes. The smoothness and isotropy of this ionized sheath are imprinted on the current sheath that travels along the electrodes, thus making it an important portion of the DPF to both understand and optimize. Here we use kinetic simulations in the Particle-in-cell code LSP to model the breakdown. Simulations are initiated with neutral gas and the breakdown modeled self-consistently as driven by a charged capacitor system. We also investigate novel geometries for the insulator and electrodes to attempt to control the electric field profile. The initial ionization fraction of gas is explored computationally to gauge possible advantages of pre-ionization which could be created experimentally via lasers or a glow-discharge. Prepared by LLNL under Contract DE-AC52-07NA27344.

  18. 自主研发电化学治疗同轴电极与传统针式电极电解效应的对比研究%The electrolytic effect in electrochemotherapy: a comparative study between self-prepared coaxial electrode and conventional needle electrode

    Institute of Scientific and Technical Information of China (English)

    张琳; 黄学全; 王健; 刘凤秀; 胡春芳

    2012-01-01

    目的 用自主研发同轴电极和直针式电极电解含百里香酚蓝琼脂-NaCl胶体系统模拟组织毁损,观察两者的电解效应,探讨自主研发同轴电极的应用价值.方法 采用百里香酚蓝琼脂-NaCl胶体系统模拟组织.在实验中保持同轴电极和针式电极的接触面积、间距一致.随着阴极周围OH-的聚集,pH升高,阴极周围胶体会变为鲜艳的蓝色.将电流分为1.6、5.0、10.0和20 mA 4组进行实验,当电量累积到1、2、4、6、8库仑时测量阴极变色范围.结果 在恒定直流电作用下,各电流组同轴电极和针式电极的阴极周围的蓝色量均随电量增加而增加,各组内同轴电极和针式电极间的作用差异无统计学意义(P >0.05).在给予相同电量时,对各电流组阴极周围的变色体积进行组间比较,差异有统计学意义(P < 0.05),即电流越小作用时间越长,变色范围越大.结论 自制同轴电极与直针式电极具有相近的电解效果,可以替代直针式电极在电化学治疗中的应用.%Objective To evaluate the electrolytic effect of a self-prepared coaxial electrode and the conventional needle electrode, and to discuss the clinical application of the self-prepared coaxial electrode. Methods The agar-NaCl colloid system, which was used as an analogue of organic tissue, was prepared for the experiment. The colloid was destructed by electrolysis by using a self-prepared coaxial electrode or a conventional needle electrode separately. The electrolytic effect of the two different electrodes was determined, and the results were compared. The anode was at the center, while the cathodes were located at the surrounding area. In the experiment, the bare surface area and the distance between the electrodes used in the experiment were the same. With the accumulation of OH- around the cathode, the pH profile rose, and meanwhile the agar-NaCl colloid around the cathodes became bright blue in color. Based on the electric

  19. Evaluation of electrolyte imbalance among tuberculosis patients ...

    African Journals Online (AJOL)

    Adebimpe Wasiu Olalekan

    2015-02-24

    Feb 24, 2015 ... electrolyte and acid-base derangements frequently encountered in AIDS and TB, have ..... tuberculosis. Electrolyte and acid-base balance monitoring in ... National Agency for the Control of HIV/AIDS NACA. Preva- lence of ...

  20. Electrolytic Preparation, Structure Characterization and Electrochemical Performance of NiOOH%羟基氧化镍的电解制备,结构表征和电化学性能研究

    Institute of Scientific and Technical Information of China (English)

    孙艳芝; 潘军青; 万平玉; 许淳淳; 刘小光

    2007-01-01

    NiOOH was prepared by one-step electrolysis of spherical Ni(OH)2 and the effects of electrolysis parameters were examined.The higly pure NiOOH was obtained after electrolysis at a current density of 60mA·g-1 and 30℃ with anodic potential controlled in the range of 1.73-1.85V (vs.Zn/ZnO) for 360min.The NiOOH samples were characterized by X-ray powder diffraction (XRD) and scanning electron microscope (SEM) analysis.Results indicate that the electrolysis product is spherical NiOOH doped with graphite.Charge and discharge tests show that the prepared NiOOH offers a discharge capacity of over 270mAh·g-1 at current density of 30mA·g-1 and can be directly used as cathode material of alkaline Zn/NiOOH batteries.Galvanostatic charge/discharge and cyclic voltammetry (CV) tests reveal good cycling reversibility of the NiOOH electrode.

  1. Electrolytic reduction of mixed (Fe, Ti) oxide using molten calcium chloride electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Panigrahi, Mrutyunjay, E-mail: mp@mail.tagen.tohoku.ac.jp [Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 2-1-1 Katahira, Aobaku, Sendai 980-8577 (Japan); Iizuka, Atsushi; Shibata, Etsuro; Nakamura, Takashi [Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 2-1-1 Katahira, Aobaku, Sendai 980-8577 (Japan)

    2013-02-15

    Highlights: Black-Right-Pointing-Pointer Tan et al. have electrolyzed mixtures of TiO{sub 2} and Fe{sub 2}O{sub 3} to produce alloys containing Fe-Ti intermetallic phases such as FeTi and Fe{sub 2}Ti using the FFC process. However, the produced alloys have a porous structure with many carbon impurities, e.g., titanium carbide (TiC). Most of the carbon contamination could be caused by the presence of carbon particles in the porous alloy structure. They did not mention any obvious ways of excluding carbon and other impurities, and only suggested that the use of mixed oxides with refined structures or using a single phase, namely ilmenite (FeO{center_dot}TiO{sub 2}), were methods of decreasing impurities in the formed alloys. For future industrialization, there is an urgent need for obvious ways of producing purer Fe-Ti alloys with dense structures, rather than porous structures, as these absorb carbon impurities. Black-Right-Pointing-Pointer Finally, we successfully reduced to a highly purified Fe-Ti intermetallic alloy of FeTi and {beta}-Ti (FeTi{sub 4}) phases. FeTi phases of size around 5-10 {mu}m were dispersed in a matrix of the {beta}-Ti (FeTi{sub 4}) phase. The carbon content of the electrolyzed alloy was as low as less than 0.01 mass%. It was suggested that the dense structure of the alloy of FeTi and {beta}-Ti (FeTi{sub 4}) avoided the inclusion of carbon particle impurities, unlike the porous alloy structure. - Abstract: The production of high-purity metals or alloys using effective technologies is critical for future industrialization. With this aim in mind, a fundamental study of electrolysis in molten CaCl{sub 2} electrolytes was conducted to develop a new production process for ferrotitanium (Fe-Ti) intermetallic alloys. Mixed solid oxides of TiO{sub 2} and Fe{sub 2}O{sub 3} were used in a molar ratio of 5.44:1.00. In this composition of Ti and Fe, FeTi and {beta}-Ti containing iron can co-exist in equilibrium. A mixed solid (Fe, Ti) oxide was reduced

  2. Effect of sintering temperature on the microstructure, roughness and electrochemical impedance of electrophoretically deposited YSZ electrolyte for SOFCs

    Energy Technology Data Exchange (ETDEWEB)

    Talebi, Tahereh; Haji, Mohsen; Raissi, Babak [Materials and Energy Research Center, P. Box 14155-4777, Karaj, Tehran (Iran)

    2010-09-15

    In the present work, the microstructures of YSZ electrolyte films, which were sintered at various temperatures in the range of 1300-1600 C, were investigated. First, a suitable and uniform film was deposited on the surface of NiO-YSZ composite by EPD. After the consequence sintering, the surfaces of deposited YSZ films were observed by SEM. In addition, other characteristics of the YSZ electrolyte films such as surface roughness and morphology of the sintered films were investigated by AFM. The ability of ionic transfer and permeability of the YSZ electrolyte was examined by electrochemical impedance spectroscopy at different temperatures. It seems that the YSZ electrolyte sintered at 1400 C was appropriate for SOFCs applications, because this film had the minimum impedance, minimum roughness and the maximum conductivity. Furthermore, the temperature of 1400 C was the minimum temperature in which a dense film of YSZ was formed uniformly on the surface of anode and coated it completely. (author)

  3. Electrolytes for magnesium electrochemical cells

    Energy Technology Data Exchange (ETDEWEB)

    Burrell, Anthony K.; Sa, Niya; Proffit, Danielle Lee; Lipson, Albert; Liao, Chen; Vaughey, John T.; Ingram, Brian J.

    2017-07-04

    An electrochemical cell includes a high voltage cathode configured to operate at 1.5 volts or greater; an anode including Mg.sup.0; and an electrolyte including an ether solvent and a magnesium salt; wherein: a concentration of the magnesium salt in the ether is 1 M or greater.

  4. Preparation of the Solid Electrolytes Li4+xAlxSi1-xO4-y Al2O3 by the Sol-Gel Method and Study of Their Ionic Conductivity

    Institute of Scientific and Technical Information of China (English)

    CHEN,Ru-Fen(陈汝芬); SONG,Xiu-Qin(宋秀芹)

    2002-01-01

    The Li4+xAlxSi1- xO4-yAl2O3(x =0 to 0.5, y =0 to 0.5) ion conductors were prepared by the Sol-Gel method and examined in detail. The powder and sintered samples were characterized by TG-DTA, XRD, SEM, and AC impedance techniques. The experimental results show that the conductivity and sinterability increase with the amount of excess Al2O3 in the silicate. The particle size of the powder samples is about 0. 13 μm. The maximum conductivity at 18 ℃ is 3.057 × 10-5 s/cm for Li4.4Al0.4Si0.6O4-0.3 Al2O3.

  5. Optimal probabilistic dense coding schemes

    Science.gov (United States)

    Kögler, Roger A.; Neves, Leonardo

    2017-04-01

    Dense coding with non-maximally entangled states has been investigated in many different scenarios. We revisit this problem for protocols adopting the standard encoding scheme. In this case, the set of possible classical messages cannot be perfectly distinguished due to the non-orthogonality of the quantum states carrying them. So far, the decoding process has been approached in two ways: (i) The message is always inferred, but with an associated (minimum) error; (ii) the message is inferred without error, but only sometimes; in case of failure, nothing else is done. Here, we generalize on these approaches and propose novel optimal probabilistic decoding schemes. The first uses quantum-state separation to increase the distinguishability of the messages with an optimal success probability. This scheme is shown to include (i) and (ii) as special cases and continuously interpolate between them, which enables the decoder to trade-off between the level of confidence desired to identify the received messages and the success probability for doing so. The second scheme, called multistage decoding, applies only for qudits ( d-level quantum systems with d>2) and consists of further attempts in the state identification process in case of failure in the first one. We show that this scheme is advantageous over (ii) as it increases the mutual information between the sender and receiver.

  6. STAR FORMATION IN DENSE CLUSTERS

    Energy Technology Data Exchange (ETDEWEB)

    Myers, Philip C., E-mail: pmyers@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2011-12-10

    A model of core-clump accretion with equally likely stopping describes star formation in the dense parts of clusters, where models of isolated collapsing cores may not apply. Each core accretes at a constant rate onto its protostar, while the surrounding clump gas accretes as a power of protostar mass. Short accretion flows resemble Shu accretion and make low-mass stars. Long flows resemble reduced Bondi accretion and make massive stars. Accretion stops due to environmental processes of dynamical ejection, gravitational competition, and gas dispersal by stellar feedback, independent of initial core structure. The model matches the field star initial mass function (IMF) from 0.01 to more than 10 solar masses. The core accretion rate and the mean accretion duration set the peak of the IMF, independent of the local Jeans mass. Massive protostars require the longest accretion durations, up to 0.5 Myr. The maximum protostar luminosity in a cluster indicates the mass and age of its oldest protostar. The distribution of protostar luminosities matches those in active star-forming regions if protostars have a constant birthrate but not if their births are coeval. For constant birthrate, the ratio of young stellar objects to protostars indicates the star-forming age of a cluster, typically {approx}1 Myr. The protostar accretion luminosity is typically less than its steady spherical value by a factor of {approx}2, consistent with models of episodic disk accretion.

  7. Star formation in dense clusters

    CERN Document Server

    Myers, Philip C

    2011-01-01

    A model of core-clump accretion with equally likely stopping describes star formation in the dense parts of clusters, where models of isolated collapsing cores may not apply. Each core accretes at a constant rate onto its protostar, while the surrounding clump gas accretes as a power of protostar mass. Short accretion flows resemble Shu accretion, and make low-mass stars. Long flows resemble reduced Bondi accretion and make massive stars. Accretion stops due to environmental processes of dynamical ejection, gravitational competition, and gas dispersal by stellar feedback, independent of initial core structure. The model matches the field star IMF from 0.01 to more than 10 solar masses. The core accretion rate and the mean accretion duration set the peak of the IMF, independent of the local Jeans mass. Massive protostars require the longest accretion durations, up to 0.5 Myr. The maximum protostar luminosity in a cluster indicates the mass and age of its oldest protostar. The distribution of protostar luminosi...

  8. Sn0.95 Ta0.05 P2 O7/PTFE复合电解质的制备及中温电性能%Preparation and Intermediate Temperature Electrical Properties of Polytetrafluoroethylene/Sn0. 95 Ta0. 05 P2 O7 Composite Electrolyte

    Institute of Scientific and Technical Information of China (English)

    王洪涛; 邹影; 王永忠; 韩燕; 吴福芳; 孙林

    2015-01-01

    The Sn0. 95 Ta0. 05 P2 O7 was obtained by a solid-state reaction method. The calculated amount of PTFE was mixed with Sn0. 95 Ta0. 05 P2 O7 according to proper weight ratio to produce new organic-inorganic composite electrolyte Sn0. 95 Ta0. 05 P2 O7/PTFE. XRD showed that the PTFE/Sn0. 95 Ta0. 05 P2 O7 showed a single cubic phase structure in agreement with that of SnP2 O7 in JCPDS ( 00-029-1352 ) , besides, there was an additional peak of polytetrafluoroethylene ( PTFE ) , there were only peaks corresponding well to Sn0. 95 Ta0. 05 P2 O7 and PTFE, without any formation of other substances. SEM images showed that composite electrolyte was sufficiently dense. The intermediate temperature conduction behavior was investigated by AC impedance spectroscopy in the range of 40~200℃. The highest conductivity was observed to be 1. 7 × 10-2 S·cm-1 for Sn0. 95 Ta0. 05 P2 O7/PTFE at 160 ℃.%先采用固相法制备Sn0.95 Ta0.05 P2 O7电解质样品,再与适量聚四氟乙烯( PTFE)进行复合合成了有机-无机复合电解质聚四氟乙烯/Sn0.95 Ta0.05 P2 O7。 XRD测试表明PTFE/Sn0.95 Ta0.05 P2 O7复合电解质衍射图谱与焦磷酸锡的JCPDS标准衍射图谱卡立方相SnP2O7(JCPDS 00-029-1352)相同,还可以看出复合后新增加了PTFE的衍射峰,表明Sn0.95Ta0.05P2O7和PTFE复合没有发生反应生成新物质。 SEM图可以看出样品致密性良好。采用电化学工作站对样品的中温电性能(40~200℃)进行了研究。结果表明, Sn0.95Ta0.05P2O7/PTFE在160℃下,电导率达到最大值为:1.7×10-2 S·cm-1。

  9. Study on rare earth electrolyte of SDC-LSGM

    Institute of Scientific and Technical Information of China (English)

    XU Dan; LIU Xiaomei; ZHU Chengjun; WANG Dejun; YAN Duanting; WANG Deyong; SU Wenhui

    2008-01-01

    Ce0.85Sm0.15O1.925 (SDC) and La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM) were synthesized using Glycine-Nitrate Process (GNP), and the composite electrolytes were prepared by mixing SDC and LSGM. An X-ray diffraction pattern indicated that the mixture of SDC and LSGM consisted of their original phases after heating at 1450 oC for 10 h. The electronic conductivity of SDC-LSGM composite electrolytes were measured by direct current polarization method using Hebb-Wagner ion blocking cell at 700-800 oC in the oxygen partial pressure range of 10-6-10-20 MPa and compared with the results of SDC. Typical polarization curves, which were theoretically predicted, were observed on all the samples. The slopes of lgσe-lgPo2 plot for all the composite electrolytes agreed with the theoretically predicted value of -1/4 at some intermediate oxygen partial pressures and -1/6 at low oxygen partial pressure. The electronic conductivity of SDC-LSGM composite electrolytes decreased with the increase in LSGM content, whereas the ionic transport number ti of all the samples increased with the increase in LSGM content.

  10. Thermophysical properties of warm dense hydrogen

    CERN Document Server

    Holst, Bastian; Desjarlais, Michael P

    2007-01-01

    We study the thermophysical properties of warm dense hydrogen using quantum molecular dynamics simulations. New results are presented for the pair distribution functions, the equation of state, the Hugoniot curve, and the reflectivity. We compare with available experimental data and predictions of the chemical picture. Especially, we discuss the nonmetal-to-metal transition which occurs at about 40 GPa in the dense fluid.

  11. Heavy meson production in hot dense matter

    NARCIS (Netherlands)

    Tolos, Laura; Gamermann, Daniel; Garcia-Recio, Carmen; Molina, Raquel; Nieves, Juan; Oset, Eulogio; Ramos, Angels; Nieves, JM; Oset, E; Vacas, MJV

    2010-01-01

    The properties of charmed mesons in dense matter are studied using a unitary coupled-channel approach in the nuclear medium which takes into account Pauli-blocking effects and meson self-energies in a self-consistent manner. We obtain the open-charm meson spectral functions in this dense nuclear env

  12. Finding dense locations in indoor tracking data

    DEFF Research Database (Denmark)

    Ahmed, Tanvir; Pedersen, Torben Bach; Lu, Hua

    2014-01-01

    Finding the dense locations in large indoor spaces is very useful for getting overloaded locations, security, crowd management, indoor navigation, and guidance. Indoor tracking data can be very large and are not readily available for finding dense locations. This paper presents a graph-based mode...

  13. Conductivity measurements of molten metal oxide electrolytes and their evaluation in a direct carbon fuel cell (DCFC)

    Science.gov (United States)

    Yarlagadda, Venkata Raviteja

    2011-12-01

    material for handling V2O5. Conductivity of TeO2was measured using a quartz crucible since it formed a Al2TeO6 complex by reacting with alumina. Ionic conductivity of TeO2 was almost as high as Bi2O 3. Performance of these molten metal oxides in a DCFC has been evaluated. Dense YSZ solid electrolyte and porous LSM cathode used in the DCFC have been prepared by high temperature sintering. Efficiency of Bi2O 3 based DCFC was mainly limited by unwanted bismuth ion reduction to bismuth metal at the carbon anode oxidation potential. Shorting of the LSM cathode by molten V2O5 leaking out of the crucible at high temperatures was found to be major concern corresponding to the performance of V2O5 and TeO2 based DCFC. Based on these results, several fundamental material issues that need to be resolved have been identified.

  14. Dense image correspondences for computer vision

    CERN Document Server

    Liu, Ce

    2016-01-01

    This book describes the fundamental building-block of many new computer vision systems: dense and robust correspondence estimation. Dense correspondence estimation techniques are now successfully being used to solve a wide range of computer vision problems, very different from the traditional applications such techniques were originally developed to solve. This book introduces the techniques used for establishing correspondences between challenging image pairs, the novel features used to make these techniques robust, and the many problems dense correspondences are now being used to solve. The book provides information to anyone attempting to utilize dense correspondences in order to solve new or existing computer vision problems. The editors describe how to solve many computer vision problems by using dense correspondence estimation. Finally, it surveys resources, code, and data necessary for expediting the development of effective correspondence-based computer vision systems.   ·         Provides i...

  15. CsSnI3-xFx固态电解质的制备及其染料敏化太阳能电池性能%Preparation of CsSnI3-xFx Solid Electrolyte and its Dye-sensitized Solar Cell Performance

    Institute of Scientific and Technical Information of China (English)

    王艳香; 黄杰; 杨志胜; 黄丽群; 李家科; 孙健

    2015-01-01

    CsSnI3-xFx solid electrolyte was prepared via solid sintering method using cesium iodide stannous iodide and tin bifluoride as raw materials. The influence of doping of CsSnI3 with F and SnF2 on the performance of solar cell was studied. The light voltage curve (I-V Curve),electrochemical impedance spectroscopy (EIS) and incident photon-to-current conversion efficiency (IPCE) were used to characterize the performance of the solar cells. The study shows that Cs,Sn,I,and F were evenly distributed within the photoanode. At an optimum molar concentration of 5.00% F and 5.00% SnF2,the cell exhibits the highest efficiency. The photoelectric conversion efficiency was 5.18 %,which was 33.58 % lower than that of liquid electrolyte (7.80 %).%以碘化铯,碘化亚锡和二氟化锡为原料,采用固相烧结法制备固态电解质CsSnI3-xFx,并测试了相应的染料敏化太阳能电池性能.主要研究了F-掺杂取代I-和SnF2负载量等对电池性能的影响.测试分析了电池的光电流和光电压曲线(I-V曲线)、电化学阻抗谱(EIS)、单色光光子-电子转换效率(IPCE).实验结果表明,当配比为CsSnI2.95F0.05外添加5%质量分数的SnF2后在450 ℃下烧成所得的固态电解质电池的性能最优,Cs、Sn、I和F元素在TiO2光阳极分布均匀,电池光电转换效率为5.18%,比液态电解质的效率(7.80%)低33.58%.

  16. A dense transparent polymeric single ion conductor for lithium ion batteries with remarkable long-term stability

    Science.gov (United States)

    Pan, Qiyun; Chen, Yazhou; Zhang, Yunfeng; Zeng, Danli; Sun, Yubao; Cheng, Hansong

    2016-12-01

    We report an outstanding electrochemical performance of a gel type lithium ion battery with long cycle life enabled by a dense transparent polymeric single ion conductor. The polymer electrolyte was synthesized by a side chain grafting method with 4-amino-4'-trifluoromethyl bis(benzene sulfonyl)imide grafted on side chains of poly(ethylene-alt-maleic anhydride) with a grafting ratio of 50%. Blending lithiated iononmers with poly(vinylidene fluoride-co-hexafluoropropylene) via a solution cast method results in a dense transparent film. The fabricated blend polymer electrolyte film has an ionic conductivity of 0.104 mS cm-1 at room temperature, a tensile strength of 15.5 MPa and percent elongation at break of 5%. A gel type single ion conductive polymeric lithium ion battery was assembled using the blend film as the separator as well as the electrolyte, LiFePO4/C mixed with ionomers as the cathode and a lithium foil as the anode. The battery delivers a reversible discharge capacity of 100 mAh g-1 at 1 C under room temperature for 1000 cycles without obvious decay. The stable cyclic imide and comb-like structure of the polymer is largely responsible for the excellent battery performance. The side chain grafted single ion conducting polymer electrolyte is well suited for large-scale production.

  17. Efficient Electrolytes for Lithium-Sulfur Batteries

    Directory of Open Access Journals (Sweden)

    Natarajan eAngulakshmi

    2015-05-01

    Full Text Available This review article mainly encompasses on the state-of-the-art electrolytes for lithium–sulfur batteries. Different strategies have been employed to address the issues of lithium-sulfur batteries across the world. One among them is identification of electrolytes and optimization of their properties for the applications in lithium-sulfur batteries. The electrolytes for lithium-sulfur batteries are broadly classified as (i non-aqueous liquid electrolytes, (ii ionic liquids, (iii solid polymer and (iv glass-ceramic electrolytes. This article presents the properties, advantages and limitations of each type of electrolytes. Also the importance of electrolyte additives on the electrochemical performance of Li-S cells is discussed.

  18. 镁合金表面ZrO2涂层的等离子体电解氧化制备及其放电特性%Preparation of ZrO2 Coatings by Plasma Electrolytic Oxidation on Surface of Magnesium Alloys and Its Discharge Characteristics

    Institute of Scientific and Technical Information of China (English)

    王丽; 付文; 陈砺

    2012-01-01

    采用等离子体电解氧化(plasma electrolytic oxidation,PEO)技术在基础电解液 K2ZrF6中,在 AZ31 镁合金表面制备 ZrO2陶瓷涂层。对 PEO 过程放电特性、等离子体场的成分、ZrO2陶瓷涂层表面及截面形貌、晶相组成、耐腐蚀性能及表面接触角进行了研究。结果表明:制得的 ZrO2陶瓷涂层表面均匀,截面致密,涂层主要由立方相、四方相及单斜相 ZrO2组成。ZrO2涂层耐腐蚀性能相对于基体提高了 6 个数量级。制得的 ZrO2陶瓷涂层表现出疏水性,有利于提高基体材料的耐腐蚀性能。等离子体场内放电火花活性物种主要由 Na、K、Mg、Al、H、O、O2、H2O、H2O+、O+、OI 及ZrO2组成。%The ZlO2 ceramic coatings on the surface of AZ31 magnesium alloy were deposited via plasma electrolytic oxidation (PEO) in a base electrolyte solution of K2ZrFt. The discharge characteristics of the PEO process, the composition of the plasma field, and the surface and cross-section morphologies of the ZrO2 ceramic coatings, the phase composition, the corrosion resistance and the surface contact angle of the coatings were investigated. The results show that the prepared ZrO2 ceramic coatings exhibit a uniform surface morphology and a compact cross section. The coatings were mainly composed of the cubic, tetragonal and monoclinlc ZrO2 phases. The corrosion resistance of the coatings was increased by 6-0rder magnitude, compared to that of the substrate. The ZrO2 ceramic coatings exhibited the hydrophobie characteristics, which could favor the improvement of the corrosion resistance of the substrate material. The active species of discharge sparks in the plasma field were composed of Na, K, Mg, A1, H, O, O2, H2O, H2O+, O+, OI and ZrO2.

  19. MCM41有序介孔SiO2表面接枝PMMA的制备及其对PMMA基聚电解质膜的改性作用研究%Preparation of Poly (methyl methacrylate) grafted Ordered Mesoporous Silica(MCM41) and Its Effect in Modifying PMMA-based Polymer Electrolyte

    Institute of Scientific and Technical Information of China (English)

    徐峰; 徐立新; 陈枫; 杨晋涛; 钟明强

    2012-01-01

    The PMMA-grafted ordered mesoporous silica (MSM41-g-PMMA) was firstly prepared by surface-initiated atom transfer radical polymerization of MMA from both interior and exterior surface of MCM41 particles. A series of PM-MA-based composite polymer electrolyte membrances were then obtained by solution casting method using propylene carbonate (PC) as plasticizer and the MCM41-g-PMMA as filler. The influence of various factors on the ionic conductivi-ty of PMMA-based composite polymer electrolyte was assessed including the loading amount of the MCM41-g-PMMA, surface modification of MCM41 and temperature as well. The results from infrared spectroscopy (IR), thermogravimetry (TGA),high resolution transmittance electron microscopy(HRTEM),small-angle X-ray diffraction(SAXRD), confirmed that the PMMA could be successfully grafted on the surface of MCM41. The results of alternating current (AC) impedance testing and differential scanning calorimetry (DSC) showed that the PMMA-based polymer electrolyte, com-posited with the MCM41-g-PMMA, exhibits higher ionic conductivity and better thermal stability compared to the bare MCM41-filled system.%通过表面引发原子转移自由基聚合技术(SI-ATRP)使聚甲基丙烯酸甲酯(PMMA)接枝于有序介孔氧化硅(MCM41)粒子的孔道内外表面,制得表面PMMA接枝的MCM41复合粒子(MCM41-g-PM-MA).进一步利用增塑剂碳酸丙烯酯(PC)与所得的MCM41-g-PMMA共同对PMMA基聚合物电解质膜进行改性,通过溶液浇铸工艺制得PMMA基复合型聚电解质膜.着重考察了MCM41-g-PMMA填充比例、MCM41表面PMMA接枝以及温度等因素对上述体系离子电导率的影响.红外光谱(FTIIR)、热重(TGA)、高倍透射电镜(HRTEM)、小角X射线衍射(SAXRD)分析结果表明:PMMA已成功接枝于MCM41粒子的孔道内外表面.交流阻抗测试、差示扫描量热分析(DSC)表明:较改性前的MCM41填充体系,MCM41-g-PMMA填充的PMMA膜具有更优的离子电导率,同时具有更佳的热稳定性能.

  20. Preparation of Al-Sr Master Alloy in Aluminum Electrolysis Cell

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Al-Sr master alloy was prepared by using liquid aluminum cathode and a mixture of Na3AlF6- SrCO3 as the basic molten salt electrolyte in a laboratory electrolysis cell.The effects of electrolyte composition,electrolysis temperature,cathodic current density and the electrolytic duration on Sr content of Al-Sr alloy were studied.Through laboratory experiments,the parameters for smooth electrolytic reaction were proposed.

  1. A study of perfluorocarboxylate ester solvents for lithium ion battery electrolytes

    Science.gov (United States)

    Fears, Tyler M.; Sacci, Robert L.; Winiarz, Jeffrey G.; Kaiser, Helmut; Taub, Haskell; Veith, Gabriel M.

    2015-12-01

    Several high-purity methyl perfluorocarboxylates were prepared (>99.5% purity by mole) and investigated as potential fluorine-rich electrolyte solvents in Li-ion batteries. The most conductive electrolyte, 0.1 M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in dimethyl perfluoroglutarate (PF5M2) (ionic conductivity = 1.87 × 10-2 mS cm-1), is investigated in Si thin-film half-cells. The solid-electrolyte-interphase (SEI) formed by the PF5M2 electrolyte is composed of similar organic and inorganic moieties and at comparable concentrations as those formed by ethylene carbonate/dimethyl carbonate electrolytes containing LiPF6 and LiTFSI salts. However, the SEI formed by the PF5M2 electrolyte undergoes reversible electrochemical defluorination, contributing to the reversible capacity of the cell and compensating in part for capacity fade in the Si electrode. While far from ideal these electrolytes provide an opportunity to further develop predictions of suitable fluorinated molecules for use in battery solvents.

  2. Water-based thixotropic polymer gel electrolyte for dye-sensitized solar cells.

    Science.gov (United States)

    Park, Se Jeong; Yoo, Kichoen; Kim, Jae-Yup; Kim, Jin Young; Lee, Doh-Kwon; Kim, Bongsoo; Kim, Honggon; Kim, Jong Hak; Cho, Jinhan; Ko, Min Jae

    2013-05-28

    For the practical application of dye-sensitized solar cells (DSSCs), it is important to replace the conventional organic solvents based electrolyte with environmentally friendly and stable ones, due to the toxicity and leakage problems. Here we report a noble water-based thixotropic polymer gel electrolyte containing xanthan gum, which satisfies both the environmentally friendliness and stability against leakage and water intrusion. For application in DSSCs, it was possible to infiltrate the prepared electrolyte into the mesoporous TiO2 electrode at the fluidic state, resulting in sufficient penetration. As a result, this electrolyte exhibited similar conversion efficiency (4.78% at 100 mW cm(-2)) and an enhanced long-term stability compared to a water-based liquid electrolyte. The effects of water on the photovoltaic properties were examined elaborately from the cyclic voltammetry curves and impedance spectra. Despite the positive shift in the conduction band potential of the TiO2 electrode, the open-circuit voltage was enhanced by addition of water in the electrolyte due to the greater positive shift in the I(-)/I3(-) redox potential. However, due to the dye desorption and decreased diffusion coefficient caused by the water content, the short-circuit photocurrent density was reduced. These results will provide great insight into the development of efficient and stable water-based electrolytes.

  3. Enhancement of ionic conductivity of PEO based polymer electrolyte by the addition of nanosize ceramic powders.

    Science.gov (United States)

    Wang, G X; Yang, L; Wang, J Z; Liu, H K; Dou, S X

    2005-07-01

    The ionic conductivity of polyethylene oxide (PEO) based solid polymer electrolytes (SPEs) has been improved by the addition of nanosize ceramic powders (TiO2 and AL2O3). The PEO based solid polymer electrolytes were prepared by the solution-casting method. Electrochemical measurement shows that the 10 wt% TiO2 PEO-LiClO4 polymer electrolyte has the best ionic conductivity (about 10(-4) S cm(-1) at 40-60 degrees C). The lithium transference number of the 10 wt% TiO2 PEO-LiClO4 polymer electrolyte was measured to be 0.47, which is much higher than that of bare PEO polymer electrolyte. Ac impedance testing shows that the interface resistance of ceramic-added PEO polymer electrolyte is stable. Linear sweep voltammetry measurement shows that the PEO polymer electrolytes are electrochemically stable in the voltage range of 2.0-5.0 V versus a Li/Li+ reference electrode.

  4. A biodegradable gel electrolyte for use in high-performance flexible supercapacitors.

    Science.gov (United States)

    Moon, Won Gyun; Kim, Gil-Pyo; Lee, Minzae; Song, Hyeon Don; Yi, Jongheop

    2015-02-18

    Despite the significant advances in solid polymer electrolytes used for supercapacitors, intractable problems including poor ionic conductivity and low electrochemical performance limit the practical applications. Herein, we report a facile approach to synthesize a NaCl-agarose gel electrolyte for use in flexible supercapacitors. The as-prepared agarose hydrogel consists of a three-dimensional chemically interconnected agarose backbone and oriented interparticular submicropores filled with water. The interconnected agarose matrix acts as a framework that provides mechanical stability to the gel electrolyte and hierarchical porous networks for optimized ion transport. The developed pores with the water filler provide an efficient ionic pathway to the storage sites of electrode. With these properties, the gel electrolyte enables the supercapacitor to have a high specific capacitance of 286.9 F g(-1) and a high rate capability that is 80% of specific capacitance obtained in the case of a liquid electrolyte at 100 mV s(-1). In addition, attributed to the simple procedure and its components, the gel electrolyte is highly scalable, cost-effective, safe, and nontoxic. Thus, the developed gel electrolyte has the potential for use in various energy storage and delivery systems.

  5. Effects of CH3OH Addition on Plasma Electrolytic Oxidation of AZ31 Magnesium Alloys

    Science.gov (United States)

    He, Yongyi; Chen, Li; Yan, Zongcheng; Zhang, Yalei

    2015-09-01

    Plasma electrolytic oxidation (PEO) films on AZ31 magnesium alloys were prepared in alkaline silicate electrolytes (base electrolyte) with the addition of different volume concentrations of CH3OH, which was used to adjust the thickness of the vapor sheath. The compositions, morphologies, and thicknesses of ceramic layers formed with different CH3OH concentrations were determined via X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and scanning electron microscopy (SEM). Corrosion behavior of the oxide films was evaluated in 3.5 wt.% NaCl solution using potentiodynamic polarization tests. PEO coatings mainly comprised Mg, MgO, and Mg2SiO4. The addition of CH3OH in base electrolytes affected the thickness, pores diameter, and Mg2SiO4 content in the films. The films formed in the electrolyte containing 12% CH3OH exhibited the highest thickness. The coatings formed in the electrolyte containing different concentrations of CH3OH exhibited similar corrosion resistance. The energy consumption of PEO markedly decreased upon the addition of CH3OH to the electrolytes. The result is helpful for energy saving in the PEO process. supported by National Natural Science Foundation of China (No. 21376088), the Project of Production, Education and Research, Guangdong Province and Ministry of Education (Nos. 2012B09100063, 2012A090300015), and Guangzhou Science and Technology Plan Projects of China (No. 2014Y2-00042)

  6. La0.8Sr0.2Fe0.8Cu0.2O3-δ as “cobalt-free” cathode for La0.8Sr0.2Ga0.8Mg0.2O3-δ electrolyte

    Science.gov (United States)

    Zurlo, Francesca; Di Bartolomeo, Elisabetta; D'Epifanio, Alessandra; Felice, Valeria; Natali Sora, Isabella; Tortora, Luca; Licoccia, Silvia

    2014-12-01

    A "cobalt-free" cathode material with stoichiometric composition La0.8Sr0.2Fe0.8Cu0.2O3-δ (LSFCu) was specifically developed for use with La0.8Sr0.2Ga0.8Mg0.2O3-δ (LSGM) electrolyte in intermediate temperature solid oxide fuel cell (IT-SOFC) systems. The chemical stability of LSFCu in contact with LSGM electrolyte was investigated by structural and morphological analysis. The electrochemical properties of LSFCu dense pellets were investigated in the temperature range 600-750 °C by electrochemical impedance spectroscopy (EIS). LSFCu|LSGM|LSFCu symmetrical cells were prepared and area specific resistance (ASR) values, directly depending on the rate limiting step of the oxygen reduction reaction, were evaluated. Fuel cells were prepared using LSFCu as cathode material on a LSGM pellet and electrochemical tests were performed in the 700-800 °C temperature range and compared to similar fuel cells prepared by using commercial La0.6Sr0.4Fe0.8Co0.2O3-δ (LSFCo) as a cathode. The maximum current density and power density recorded for LSFCu and LSFCo were similar. This fact demonstrates that Cu can be used as Co substitute in perovskite cathode materials.

  7. Investigation of polymer electrolyte based on agar and ionic liquids

    Directory of Open Access Journals (Sweden)

    M. M. Silva

    2012-12-01

    Full Text Available The possibility to use natural polymer as ionic conducting matrix was investigated in this study. Samples of agarbased electrolytes with different ionic liquids were prepared and characterized by physical and chemical analyses. The ionic liquids used in this work were 1-ethyl-3-methylimidazolium ethylsulfate, [C2mim][C2SO4], 1-ethyl-3-methylimidazolium acetate, [C2mim][OAc] and trimethyl-ethanolammonium acetate, [Ch][OAc]. Samples of solvent-free electrolytes were prepared and characterized by ionic conductivity measurements, thermal analysis, electrochemical stability, X-ray diffraction, scanning electron microscopy and Fourier Transform infrared spectroscopy. Electrolyte samples are thermally stable up to approximately 190°C. All the materials synthesized are semicrystalline. The electrochemical stability domain of all samples is about 2.0 V versus Li/Li+. The preliminary studies carried out with electrochromic devices (ECDs incorporating optimized compositions have confirmed that these materials may perform as satisfactory multifunctional component layers in the field of ‘smart windows’, as well as ECD-based devices.

  8. Thermal stability of the C106 dye in robust electrolytes

    DEFF Research Database (Denmark)

    Lund, Torben; Phuong, Nguyen Tuyet; Pechy, Peter

    Thermal stability of the C106 dye in robust electrolytes. We have investigated the thermal stability and degradation chemistry of the ruthenium dye C106 (Figure 1) at 80 ◦C in the “robust” electrolyte “B” comprised of 1.0 M DMII, 0.03 M I2, 0.5 M NBB, and 0.1 M GuNCS in 3-methoxypropionitrile (3......-MPN) introduced by Gao et al. in 2008. [1]. Figure 1 Thermal degradation of C106 bound to TiO2 at 80 ºC in dark as a function of heating time. ● C106 = RuLL´(NCS)2 ■ RuLL´(NCS)(NBB)+ ▲ RuLL´(NCS)(3-MPN)+ The C106 dye was attached to the surface of TiO2 nano-particles and stable colloidal solutions...... of the particles were prepared in electrolyte mixture B. The solutions were thermally treated at 80 ◦C for 0-2000 hours followed by dye extraction and analysis by HPLC coupled to UV/Vis and electro spray mass spectrometry [2]. Figure 1 shows the concentration profiles of C106 samples prepared under ambient...

  9. Electrochromic Device with Polymer Electrolyte

    Science.gov (United States)

    Solovyev, Andrey A.; Zakharov, Alexander N.; Rabotkin, Sergey V.; Kovsharov, Nikolay F.

    2016-08-01

    In this study a solid-state electrochromic device (ECD) comprised of a WO3 and Prussian blue (Fe4[Fe(CN)6]3) thin film couple with a Li+-conducting solid polymer electrolyte is discussed. WO3 was deposited on K-Glass substrate by magnetron sputtering method, while Prussian blue layer was formed on the same substrate by electrodeposition method. The parameters of the electrochromic device K-Glass/WO3/Li+-electrolyte/PB/K-Glass, such as change of transmittance, response time and stability were successfully tested using coupled optoelectrochemical methods. The device was colored or bleached by the application of +2 V or -2 V, respectively. Light modulation with transmittance variation of up to 59% and coloration efficiency of 43 cm2/C at a wavelength of 550 nm were obtained. Numerous switching of the ECD over 1200 cycles without the observation of significant degradation has been demonstrated.

  10. Composite electrode/electrolyte structure

    Science.gov (United States)

    Visco, Steven J.; Jacobson, Craig P.; DeJonghe, Lutgard C.

    2004-01-27

    Provided is an electrode fabricated from highly electronically conductive materials such as metals, metal alloys, or electronically conductive ceramics. The electronic conductivity of the electrode substrate is maximized. Onto this electrode in the green state, a green ionic (e.g., electrolyte) film is deposited and the assembly is co-fired at a temperature suitable to fully densify the film while the substrate retains porosity. Subsequently, a catalytic material is added to the electrode structure by infiltration of a metal salt and subsequent low temperature firing. The invention allows for an electrode with high electronic conductivity and sufficient catalytic activity to achieve high power density in ionic (electrochemical) devices such as fuel cells and electrolytic gas separation systems.

  11. Electrolyte leakage as an indicator

    Directory of Open Access Journals (Sweden)

    ahmad nezami

    2009-06-01

    Full Text Available In order to evaluate the electrolyte leakage as an indicator of freezing injury in colza (Brassica napus L. genotypes under controlled conditions, a trial carried out at the green house of College of Agriculture, Ferdowsi University of Mashhad. In this study 10 rapeseed genotypes, with 5 temperatures (0, -4, -8, -12 and -16 °C on subplot and acclimation and non acclimation on main plot were evaluated on RCD factorial split plot with two replications. Plants were kept until 3-5 leaf stage in green house condition with 23/16 2 °C (day/night and natural photoperiod. Pots were subjected to acclimation (for three weeks or non acclimation that plants immediately frozen.For acclimation treatment after three weeks freezing was done in thermogradient freezer. The cell membrane integrity was measured through electrolyte leakage and the lethal temperature 50 (LT50 of samples also were determined. There were significant differences (p

  12. New Polymer Electrolyte Cell Systems

    Science.gov (United States)

    Smyrl, William H.; Owens, Boone B.; Mann, Kent; Pappenfus, T.; Henderson, W.

    2004-01-01

    PAPERS PUBLISHED: 1. Pappenfus, Ted M.; Henderson, Wesley A.; Owens, Boone B.; Mann, Kent R.; Smyrl, William H. Complexes of Lithium Imide Salts with Tetraglyme and Their Polyelectrolyte Composite Materials. Journal of the Electrochemical Society (2004), 15 1 (2), A209-A2 15. 2. Pappenfus, Ted M.; Henderson, Wesley A.; Owens, Boone B.; Mann, Kent R.; Smyrl, William H. Ionic-liquidlpolymer electrolyte composite materials for electrochemical device applications. Polymeric Materials Science and Engineering (2003), 88 302. 3. Pappenfus, Ted R.; Henderson, Wesley A.; Owens, Boone B.; Mann, Kent R.; and Smyrl, William H. Ionic Conductivity of a poly(vinylpyridinium)/Silver Iodide Solid Polymer Electrolyte System. Solid State Ionics (in press 2004). 4. Pappenfus Ted M.; Mann, Kent R; Smyrl, William H. Polyelectrolyte Composite Materials with LiPFs and Tetraglyme. Electrochemical and Solid State Letters, (2004), 7(8), A254.

  13. Electrospun PVdF-PVC nanofibrous polymer electrolytes for polymer lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zhong Zheng [Key Laboratory of Environmentally Friendly Chemistry and Applications of Minister of Education, College of Chemistry, Xiangtan University, Xiangtan 411105 (China); Cao Qi, E-mail: wjcaoqi@163.com [Key Laboratory of Environmentally Friendly Chemistry and Applications of Minister of Education, College of Chemistry, Xiangtan University, Xiangtan 411105 (China); Jing Bo; Wang Xianyou; Li Xiaoyun; Deng Huayang [Key Laboratory of Environmentally Friendly Chemistry and Applications of Minister of Education, College of Chemistry, Xiangtan University, Xiangtan 411105 (China)

    2012-01-25

    Highlights: Black-Right-Pointing-Pointer The nanofibrous polymer electrolytes based on PVdF-PVC (8:2, w/w) prepared by electrospinning have an ionic conductivity of 2.25 Multiplication-Sign 10{sup -3} S cm{sup -1} at 25 Degree-Sign C. Black-Right-Pointing-Pointer The nanofibrous polymer electrolytes presented a good electrochemical stability up to 5.1 V (vs. Li/Li{sup +}). Black-Right-Pointing-Pointer The nanofibrous polymer electrolytes showed a very good charge/discharge and cycling performance. - Abstract: Nanofibrous membranes based on Poly (vinyl difluoride) (PVdF)-Poly (vinyl chloride) (PVC) (8:2, w/w) were prepared by electrospinning and then they were soaked in a liquid electrolyte to form polymer electrolytes (PEs). The morphology, thermal stability, function groups and crystallinity of the electrospun membranes were characterized by scanning electron microscope (SEM), thermal analysis (TG), Fourier transform infrared spectra (FT-IR) and differential scanning calorimetry (DSC), respectively. It was found that both electrolyte uptake and ionic conductivity of the composite PEs increased with the addition of PVC. The composite PVdF-PVC PEs had a high ionic conductivity up to 2.25 Multiplication-Sign 10{sup -3} S cm{sup -1} at 25 Degree-Sign C. These results showed that nanofibrous PEs based on PVdF-PVC were of great potential application in polymer lithium-ion batteries.

  14. Hierarchically oriented macroporous anode-supported solid oxide fuel cell with thin ceria electrolyte film.

    Science.gov (United States)

    Chen, Yu; Zhang, Yanxiang; Baker, Jeffrey; Majumdar, Prasun; Yang, Zhibin; Han, Minfang; Chen, Fanglin

    2014-04-09

    Application of anode-supported solid oxide fuel cell (SOFC) with ceria based electrolyte has often been limited by high cost of electrolyte film fabrication and high electrode polarization. In this study, dense Gd0.1Ce0.9O2 (GDC) thin film electrolytes have been fabricated on hierarchically oriented macroporous NiO-GDC anodes by a combination of freeze-drying tape-casting of the NiO-GDC anode, drop-coating GDC slurry on NiO-GDC anode, and co-firing the electrolyte/anode bilayers. Using 3D X-ray microscopy and subsequent analysis, it has been determined that the NiO-GDC anode substrates have a porosity of around 42% and channel size from around 10 μm at the electrolyte side to around 20 μm at the other side of the NiO-GDC (away from the electrolyte), indicating a hierarchically oriented macroporous NiO-GDC microstructure. Such NiO-GDC microstructure shows a tortuosity factor of ∼1.3 along the thickness direction, expecting to facilitate gas diffusion in the anode during fuel cell operation. SOFCs with such Ni-GDC anode, GDC film (30 μm) electrolyte, and La0.6Sr0.4Co0.2Fe0.8O3-GDC (LSCF-GDC) cathode show significantly enhanced cell power output of 1.021 W cm(-2) at 600 °C using H2 as fuel and ambient air as oxidant. Electrochemical Impedance Spectroscopy (EIS) analysis indicates a decrease in both activation and concentration polarizations. This study has demonstrated that freeze-drying tape-casting is a very promising approach to fabricate hierarchically oriented porous substrate for SOFC and other applications.

  15. Room temperature magnesium electrorefining by using non-aqueous electrolyte

    Science.gov (United States)

    Park, Jesik; Jung, Yeojin; Kusumah, Priyandi; Dilasari, Bonita; Ku, Heesuk; Kim, Hansu; Kwon, Kyungjung; Lee, Churl Kyoung

    2016-09-01

    The increasing usage of magnesium inevitably leads to a fast increase in magnesium scrap, and magnesium recycling appears extremely beneficial for cost reduction, preservation of natural resources and protection of the environment. Magnesium refining for the recovery of high purity magnesium from metal scrap alloy (AZ31B composed of magnesium, aluminum, zinc, manganese and copper) at room temperature is investigated with a non-aqueous electrolyte (tetrahydrofuran with ethyl magnesium bromide). A high purity (99.999%) of electrorefined magneisum with a smooth and dense surface is obtained after potentiostatic electrolysis with an applied voltage of 2 V. The selective dissolution of magnesium from magnesium alloy is possible by applying an adequate potential considering the tolerable impurity level in electrorefined magnesium and processing time. The purity estimation method suggested in this study can be useful in evaluating the maximum content of impurity elements.

  16. Layered double hydroxides as an effective additive in polymer gelled electrolyte based dye-sensitized solar cells.

    Science.gov (United States)

    Ho, Hsu-Wen; Cheng, Wei-Yun; Lo, Yu-Chun; Wei, Tzu-Chien; Lu, Shih-Yuan

    2014-10-22

    Layered double hydroxides (LDH), a class of anionic clay materials, were developed as an effective additive for polymer gelled electrolytes for use in dye-sensitized solar cells (DSSC). Carbonate and chloride intercalated Zn-Al LDHs, ZnAl-CO3 LDH, and ZnAl-Cl LDH were prepared with coprecipitation methods. The addition of the two LDHs significantly improved, in terms of power conversion efficiency (PCE), over the plain poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) gelled electrolyte and competed favorably with the liquid electrolyte based DSSCs, 8.13% for the liquid electrolyte, 7.48% for the plain PVDF-HFP gelled electrolyte, 8.11% for the ZnAl-CO3 LDH/PVDF-HFP gelled electrolyte, and 8.00% for the ZnAl-Cl LDH/PVDF-HFP gelled electrolyte based DSSCs. The good performance in PCEs achieved by the LDH-loaded DSSCs came mainly from the significant boost in open circuit voltages (Voc), from 0.74 V for both the liquid electrolyte and PVDF-HFP gelled electrolyte based DSSCs to 0.79 V for both the ZnAl-CO3 LDH/PVDF-HFP and ZnAl-Cl LDH/PVDF-HFP gelled electrolyte based DSSCs. The boost in Voc was contributed mainly by the positive shift in redox potential of the redox couple, I(-)/I3(-), as revealed from cyclic voltammetry analyses. As for the long-term stability, PCE retention rates of 96 and 99% after 504 h were achieved by the ZnAl-CO3 LDH/PVDF-HFP and ZnAl-Cl LDH/PVDF-HFP gelled electrolyte based DSSCs, respectively, appreciably better than 92% achieved by the liquid electrolyte based one after 480 h.

  17. Superconductivity in dense MgB2 wires.

    Science.gov (United States)

    Canfield, P C; Finnemore, D K; Bud'ko, S L; Ostenson, J E; Lapertot, G; Cunningham, C E; Petrovic, C

    2001-03-12

    MgB2 becomes superconducting just below 40 K. Whereas porous polycrystalline samples of MgB2 can be synthesized from boron powders, in this Letter we demonstrate that dense wires of MgB2 can be prepared by exposing boron filaments to Mg vapor. The resulting wires have a diameter of 160 microm, are better than 80% dense, and manifest the full chi = -1/4pi shielding in the superconducting state. Temperature-dependent resistivity measurements indicate that MgB2 is a highly conducting metal in the normal state with rho(40 K) = 0.38 microOmega cm. By using this value, an electronic mean-free path, l approximately 600 A can be estimated, indicating that MgB2 wires are well within the clean limit. Tc, Hc2(T), and Jc data indicate that MgB2 manifests comparable or better superconducting properties in dense wire form than it manifests as a sintered pellet.

  18. Novel polymer electrolyte from poly(carbonate-ether) and lithium tetrafluoroborate for lithium-oxygen battery

    Science.gov (United States)

    Lu, Qi; Gao, Yonggang; Zhao, Qiang; Li, Ji; Wang, Xianhong; Wang, Fosong

    2013-11-01

    Novel polymer electrolyte based on low-molecular weight poly(carbonate-ether) and lithium tetrafluoroborate has been prepared and used in lithium-oxygen battery for the first time, the electrolyte with approximate 17% of LiBF4 showed ionic conductivity of 1.57 mS cm-1. Infrared spectra analysis indicates that obvious interaction between the lithium ions and partial oxygen atoms in the host polymer exists, and the lithium salt and the host polymer have good miscibility. The lithium-oxygen battery from this polymer electrolyte shows similar cyclic stability to traditional liquid electrolyte observed by FT-IR, AFM and electrochemical measurements, which may provide a new choice for fabrication of all-solid-state high-capacity rechargeable lithium-oxygen battery with better safety.

  19. High-performance gel electrolytes with tetra-armed polymer network for Li ion batteries

    Science.gov (United States)

    Hazama, Taisuke; Fujii, Kenta; Sakai, Takamasa; Aoki, Masahiro; Mimura, Hideyuki; Eguchi, Hisao; Todorov, Yanko; Yoshimoto, Nobuko; Morita, Masayuki

    2015-07-01

    An organo gel with only 6 wt % tetra-armed poly(ethylene glycol), TetraPEG, was prepared and applied as a novel gel electrolyte for Li ion batteries (LIBs). The TetraPEG gel electrolyte containing 1.0 M LiPF6 in binary or ternary mixtures, i.e., EC + DEC and EC + DEC + TFEP (EC: ethylene carbonate, DEC: diethyl carbonate and TFEP: tris(2,2,2-trifluoroethyl)phosphate showed high ionic conductivity required for the use in LIB systems. The TetraPEG gel based on ternary EC + DEC + TFEP system acts as a nonflammable gel electrolyte at the TFEP content higher than 20 vol%. In cyclic voltammetry and charge/discharge cycling tests, the TetraPEG gel electrolytes showed good reversibility for a graphite negative electrode.

  20. Effect of complexing salt on conductivity of PVC/PEO polymer blend electrolytes

    Indian Academy of Sciences (India)

    S Rajendran; Ravi Shanker Babu; M Usha Rani

    2011-12-01

    Solid polymer electrolyte membrane comprising poly(vinyl chloride) (PVC), poly(ehylene oxide) (PEO) and different lithium salts (LiClO4, LiBF4 and LiCF3SO3) were prepared by the solution casting technique. The effect of complexing salt on the ionic conductivity of the PVC/PEO host polymer is discussed. Solid polymer electrolyte films were characterized by X-ray diffraction, FTIR spectroscopy, TG/DTA and ac impedance spectroscopic studies. The conductivity studies of these solid polymer electrolyte (SPE) films are carried out as a function of frequency at various temperatures ranging from 302 K to 353 K. The maximum room temperature ionic conductivity is found to be 0.079 × 10-4 S cm-1 for the film containing LiBF4 as the complexing salt. The temperature dependence of the conductivity of polymer electrolyte films seems to obey the Vogel–Tamman–Fulcher (VTF) relation.

  1. FTIR AND IONIC CONDUCTIVITY STUDIES ON BLEND POLYMER ELECTROLYTES

    Directory of Open Access Journals (Sweden)

    J. Senthil

    2011-08-01

    Full Text Available Investigations on structural and conductivity properties of solid polymer complexes have attracted a high degree of attention. The main applications of solid polymer electrolytes (SPEs are found in varioussecondary batteries and energy conversion units. In view of the abundant resources, low costs and relatively low reactivity of magnesium, solid-state batteries using magnesium metal are worthy of investigations. The polymer electrolytes were prepared using poly methyl methacrylate (PMMA, poly vinyl chloride (PVC and magnesium chloride (MgCl2 by solvent casting technique. The complex formation and ionic conductivity were characterized by Fourier Transform Infra Red spectroscopy (FTIR and impedance spectroscopy respectively.The FTIR studies provide the evidence of interaction of cation Mg2+ with the polymers. The maximum conductivity found for PMMA-MgCl2 is 0.57 x 10-7 Scm-1 at room temperature.

  2. Synthesis of tetramethyl ammonium hydroxide by cell diaphragm electrolytic method

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Under the conditions of tetramethyl ammonia chloride (TMAC) used as starting material, Ti-based Dimensionally Stable Anode (DSA), stainless steel used as cathode and Nafion 900 cation membrane as cell diaphragm, this paper studies the synthesis of tetramethyl ammonium hydroxide (TMAH) by cell diaphragm electrolytic method, examining not only the effects of current density, concentration of starting material and cell temperature, on the product purity and current efficiency, but also the effects of electrolyte circulation rate on the service life of Ti-based DSA.The experiment puts forward an optimum processing condition, and experimental findings show that preparing TMAH by using this technique can obtain a current efficiency 74.7 % and get product with a purity greater than 99.9%.

  3. Increasing the performance of tritium analysis by electrolytic enrichment.

    Science.gov (United States)

    Groning, M; Auer, R; Brummer, D; Jaklitsch, M; Sambandam, C; Tanweer, A; Tatzber, H

    2009-06-01

    Several improvements are described for the existing tritium enrichment system at the Isotope Hydrology Laboratory of the International Atomic Energy Agency for processing natural water samples. The improvements include a simple method for pretreatment of electrolytic cells to ensure a high tritium separation factor, an improved design of the exhaust system for explosive gases, and a vacuum distillation line for faster initial preparation of water samples for electrolytic enrichment and for tritium analysis. Achievements included the reduction of variation of individual enrichment parameters of all cells to less than 1% and an improvement of 50% of the stability of the background mean. It resulted in an improved detection limit of less than 0.4 TU (at 2s), important for application of tritium measurements in the future at low concentration levels, and resulted in measurement precisions of+/-0.2 TU and+/-0.15 TU for liquid scintillation counting and for gas proportional counting, respectively.

  4. A Suitable Polysulfide Electrolyte for CdSe Quantum Dot-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    H. K. Jun

    2013-01-01

    Full Text Available A polysulfide liquid electrolyte is developed for the application in CdSe quantum dot-sensitized solar cells (QDSSCs. A solvent consisting of ethanol and water in the ratio of 8 : 2 by volume has been found as the optimum solvent for preparing the liquid electrolytes. This solvent ratio appears to give higher cell efficiency compared to pure ethanol or water as a solvent. Na2S and S give rise to a good redox couple in the electrolyte for QDSSC operation, and the optimum concentrations required are 0.5 M and 0.1 M, respectively. Addition of guanidine thiocyanate (GuSCN to the electrolyte further enhances the performance. The QDSSC with CdSe sensitized electrode prepared using 7 cycles of successive ionic layer adsorption and reaction (SILAR produces an efficiency of 1.41% with a fill factor of 44% on using a polysulfide electrolyte of 0.5 M Na2S, 0.1 M S, and 0.05 M GuSCN in ethanol/water (8 : 2 by volume under the illumination of 100 mW/cm2 white light. Inclusion of small amount of TiO2 nanoparticles into the electrolyte helps to stabilize the polysulfide electrolyte and thereby improve the stability of the CdSe QDSSC. The CdSe QDs are also found to be stable in the optimized polysulfide liquid electrolyte.

  5. Corrosion behavior of Ni-based structural materials for electrolytic reduction in lithium molten salt

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Soo Haeng, E-mail: nshcho1@kaeri.re.kr [Korea Atomic Energy Research Institute, 1045 Daedeokdaero Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Park, Sung Bin [Korea Atomic Energy Research Institute, 1045 Daedeokdaero Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Lee, Jong Hyeon, E-mail: jonglee@cnu.ac.kr [Graduate School of Green Energy Technology, Chungnam National University, 79 Daehak-ro, Yuseong-gu, Daejeon 305-764 (Korea, Republic of); Hur, Jin Mok; Lee, Han Soo [Korea Atomic Energy Research Institute, 1045 Daedeokdaero Yuseong-gu, Daejeon 305-353 (Korea, Republic of)

    2011-05-01

    In this study, the corrosion behavior of new Ni-based structural materials was studied for electrolytic reduction after exposure to LiCl-Li{sub 2}O molten salt at 650 deg. C for 24-216 h under an oxidizing atmosphere. The new alloys with Ni, Cr, Al, Si, and Nb as the major components were melted at 1700 deg. C under an inert atmosphere. The melt was poured into a preheated metallic mold to prepare an as-cast alloy. The corrosion products and fine structures of the corroded specimens were characterized by scanning electron microscope (SEM), Energy Dispersive X-ray Spectroscope (EDS), and X-ray diffraction (XRD). The corrosion products of as cast and heat treated low Si/high Ti alloys were Cr{sub 2}O{sub 3}, NiCr{sub 2}O{sub 4}, Ni, NiO, and (Al,Nb,Ti)O{sub 2}; those of as cast and heat treated high Si/low Ti alloys were Cr{sub 2}O{sub 3}, NiCr{sub 2}O{sub 4}, Ni, and NiO. The corrosion layers of as cast and heat treated low Si/high Ti alloys were continuous and dense. However, those of as cast and heat treated high Si/low Ti alloys were discontinuous and cracked. Heat treated low Si/high Ti alloy showed the highest corrosion resistance among the examined alloys. The superior corrosion resistance of the heat treated low Si/high Ti alloy was attributed to the addition of an appropriate amount of Si, and the metallurgical evaluations were performed systematically.

  6. Electrospun PVdF-based fibrous polymer electrolytes for lithium ion polymer batteries

    Energy Technology Data Exchange (ETDEWEB)

    Jeong Rae Kim [Hanyang University, Seoul (France). Applied Chemical Engineering Division; Korea Institute of Science and Technology, Seoul (Korea). Polymer Hybrid Research Center; Sung Won Choi [Yonsei University, Seoul (Korea). Department of Chemistry; Seong Mu Jo; Wha Seop Lee [Korea Institute of Science and Technology, Seoul (Korea). Polymer Hybrid Research Center; Byung Chul Kim [Hanyang University, Seoul (France). Applied Chemical Engineering Division

    2004-11-15

    This paper discusses the preparation of microporous fibrous membranes from PVdF solutions with different polymer contents, using the electrospinning technique. Electrospun PVdF-based fibrous membranes with average fiber diameters (AFD's) of 0.45-1.38 {mu}m have an apparent porosity and a mean pore size (MPS) of 80-89% and 1.1-4.3 {mu}m, respectively. They exhibited a high uptake of the electrolyte solution (320-350%) and a high ionic conductivity of above 1 x 10{sup -3} s/cm at room temperature. Their ionic conductivity increased with the decrease in the AFD of the fibrous membrane due to its high electrolyte uptake. The interaction between the electrolyte molecules and the PVdF with a high crystalline content may have had a minor effect on the lithium ion transfer in the fibrous polymer electrolyte, unlike in a nanoporous gel polymer electrolyte. The fibrous polymer electrolyte that contained a 1 M LiPF{sub 6}-EC/DMC/DEC (1/1/1 by weight) solution showed a high electrochemical stability of above 5.0 V, which increased with the decrease in the AFD. The interfacial resistance (R{sub i}) between the polymer electrolyte and the lithium electrode slightly increased with the storage time, compared with the higher increase in the interfacial resistance of other gel polymer electrolytes. The prototype cell (MCMB/PVdF-based fibrous electrolyte/LiCoO{sub 2}) showed a very stable charge-discharge behavior with a slight capacity loss under constant current and voltage conditions at the C/2-rate of 20 and 60 {sup o}C. (author)

  7. Electrospun PVdF-based fibrous polymer electrolytes for lithium ion polymer batteries

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Rae [Applied Chemical Engineering Division, Hanyang University, 17, Haengdang-dong, Seongdong-Ku, Seoul 133-791 (Korea, Republic of); Polymer Hybrid Research Center, Korea Institute of Science and Technology, 39-1, Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Choi, Sung Won [Department of Chemistry, Yonsei University, 134, Sinchon-dong, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Polymer Hybrid Research Center, Korea Institute of Science and Technology, 39-1, Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Jo, Seong Mu [Polymer Hybrid Research Center, Korea Institute of Science and Technology, 39-1, Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of)]. E-mail: smjo@kist.re.kr; Lee, Wha Seop [Polymer Hybrid Research Center, Korea Institute of Science and Technology, 39-1, Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Kim, Byung Chul [Applied Chemical Engineering Division, Hanyang University, 17, Haengdang-dong, Seongdong-Ku, Seoul 133-791 (Korea, Republic of)

    2004-11-15

    This paper discusses the preparation of microporous fibrous membranes from PVdF solutions with different polymer contents, using the electrospinning technique. Electrospun PVdF-based fibrous membranes with average fiber diameters (AFD's) of 0.45-1.38 {mu}m have an apparent porosity and a mean pore size (MPS) of 80-89% and 1.1-4.3 {mu}m, respectively. They exhibited a high uptake of the electrolyte solution (320-350%) and a high ionic conductivity of above 1 x 10{sup -3} s/cm at room temperature. Their ionic conductivity increased with the decrease in the AFD of the fibrous membrane due to its high electrolyte uptake. The interaction between the electrolyte molecules and the PVdF with a high crystalline content may have had a minor effect on the lithium ion transfer in the fibrous polymer electrolyte, unlike in a nanoporous gel polymer electrolyte. The fibrous polymer electrolyte that contained a 1 M LiPF{sub 6}-EC/DMC/DEC (1/1/1 by weight) solution showed a high electrochemical stability of above 5.0 V, which increased with the decrease in the AFD The interfacial resistance (R{sub i}) between the polymer electrolyte and the lithium electrode slightly increased with the storage time, compared with the higher increase in the interfacial resistance of other gel polymer electrolytes. The prototype cell (MCMB/PVdF-based fibrous electrolyte/LiCoO{sub 2}) showed a very stable charge-discharge behavior with a slight capacity loss under constant current and voltage conditions at the C/2-rate of 20 and 60 deg. C.

  8. Improved ionic conductivity of lithium-zinc-tellurite glass-ceramic electrolytes

    Science.gov (United States)

    Widanarto, W.; Ramdhan, A. M.; Ghoshal, S. K.; Effendi, M.; Cahyanto, W. T.; Warsito

    An enhancement in the secondary battery safety demands the optimum synthesis of glass-ceramics electrolytes with modified ionic conductivity. To achieve improved ionic conductivity and safer operation of the battery, we synthesized Li2O included zinc-tellurite glass-ceramics based electrolytes of chemical composition (85-x)TeO2·xLi2O·15ZnO, where x = 0, 5, 10, 15 mol%. Samples were prepared using the melt quenching method at 800 °C followed by thermal annealing at 320 °C for 3 h and characterized. The effects of varying temperature, alternating current (AC) frequency and Li2O concentration on the structure and ionic conductivity of such glass-ceramics were determined. The SEM images of the annealed glass-ceramic electrolytes displayed rough surface with a uniform distribution of nucleated crystal flakes with sizes less than 1 μm. X-ray diffraction analysis confirmed the well crystalline nature of achieved electrolytes. Incorporation of Li2O in the electrolytes was found to generate some new crystalline phases including hexagonal Li6(TeO6), monoclinic Zn2Te3O8 and monoclinic Li2Te2O5. The estimated crystallite size of the electrolyte was ranged from ≈40 to 80 nm. AC impedance measurement revealed that the variation in the temperatures, Li2O contents, and high AC frequencies have a significant influence on the ionic conductivity of the electrolytes. Furthermore, electrolyte doped with 15 mol% of Li2O exhibited the optimum performance with an ionic conductivity ≈2.4 × 10-7 S cm-1 at the frequency of 54 Hz and in the temperature range of 323-473 K. This enhancement in the conductivity was attributed to the sizable alteration in the ions vibration and ruptures of covalent bonds in the electrolytes network structures.

  9. Anion selective membrane. [ion exchange resins and ion exchange membrane electrolytes for electrolytic cells

    Science.gov (United States)

    Alexander, S. S.; Geoffroy, R. R.; Hodgdon, R. B.

    1975-01-01

    Experimental anion permselective membranes were prepared and tested for their suitability as cell separators in a chemical redox power storage system being developed at NASA-Lewis Research Center. The goals of long-term (1000 hr) oxidative and thermal stability at 80 C in FeCl3 and CrCl3 electrolytes were met by most of the weak base and strong base amino exchange groups considered in the program. Good stability is exhibited by several of the membrane substrate resins. These are 'styrene' divinylbenzene copolymer and PVC film. At least four membrane systems produce strong flexible films with electrochemical properties (resistivity, cation transfer) superior to those of the 103QZL, the most promising commercial membrane. The physical and chemical properties of the resins are listed.

  10. Kinetic chemistry of dense interstellar clouds

    Energy Technology Data Exchange (ETDEWEB)

    Graedel, T.E.; Langer, W.D.; Frerking, M.A.

    1982-03-01

    A detailed model of the time-dependent chemistry of dense interstellar clouds has been developed to study the dominant chemical processes in carbon and oxygen isotope fractionation, formation of nitrogen-containing molecules, evolution of product molecules as a function of cloud density and temperature, and other topics of interest. The full computation involves 328 individual reactions (expanded to 1067 to study carbon and oxygen isotope chemistry); photodegradation processes are unimportant in these dense clouds and are excluded.

  11. Electrolytic hydrogen fuel production with solid polymer electrolyte technology.

    Science.gov (United States)

    Titterington, W. A.; Fickett, A. P.

    1973-01-01

    A water electrolysis technology based on a solid polymer electrolyte (SPE) concept is presented for applicability to large-scale hydrogen production in a future energy system. High cell current density operation is selected for the application, and supporting cell test performance data are presented. Demonstrated cell life data are included to support the adaptability of the SPE system to large-size hydrogen generation utility plants as needed for bulk energy storage or transmission. The inherent system advantages of the acid SPE electrolysis technology are explained. System performance predictions are made through the year 2000, along with plant capital and operating cost projections.

  12. Nanocomposite polymer electrolyte for rechargeable magnesium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Yuyan; Rajput, Nav Nidhi; Hu, Jian Z.; Hu, Mary Y.; Liu, Tianbiao L.; Wei, Zhehao; Gu, Meng; Deng, Xuchu; Xu, Suochang; Han, Kee Sung; Wang, Jiulin; Nie, Zimin; Li, Guosheng; Zavadil, K.; Xiao, Jie; Wang, Chong M.; Henderson, Wesley A.; Zhang, Jiguang; Wang, Yong; Mueller, Karl T.; Persson, Kristin A.; Liu, Jun

    2014-12-28

    Nanocomposite polymer electrolytes present new opportunities for rechargeable magnesium batteries. However, few polymer electrolytes have demonstrated reversible Mg deposition/dissolution and those that have still contain volatile liquids such as tetrahydrofuran (THF). In this work, we report a nanocomposite polymer electrolyte based on poly(ethylene oxide) (PEO), Mg(BH4)2 and MgO nanoparticles for rechargeable Mg batteries. Cells with this electrolyte have a high coulombic efficiency of 98% for Mg plating/stripping and a high cycling stability. Through combined experiment-modeling investigations, a correlation between improved solvation of the salt and solvent chain length, chelation and oxygen denticity is established. Following the same trend, the nanocomposite polymer electrolyte is inferred to enhance the dissociation of the salt Mg(BH4)2 and thus improve the electrochemical performance. The insights and design metrics thus obtained may be used in nanocomposite electrolytes for other multivalent systems.

  13. Electrolyte Additives for Phosphoric Acid Fuel Cells

    DEFF Research Database (Denmark)

    Gang, Xiao; Hjuler, H.A.; Olsen, C.A.

    1993-01-01

    Electrochemical characteristics of a series of modified phosphoric acid electrolytes containing fluorinated car on compounds and silicone fluids as additives are presented. When used in phosphoric acid fuel cells, the modified electrolytes improve the performance due to the enhanced oxygen...... reduction rate. Among useful additives we found potassium perfluorohexanesulfonate (C6F13SO3K), potassium nonafluorobutanesulfonate (C4F9SO3K), perfluorotributylamine [(C4F9)3N], and polymethylsiloxanes [(-Si(CH3)2O-)n]. The wettability of the electrodes by the modified electrolytes also is discussed......, as a fuel-cell performance with the modified electrolytes. Specific conductivity measurements of some of the modified phosphoric acid electrolytes are reported. At a given temperature, the conductivity of the C4F9SO3K-modified electrolyte decreases with an increasing amount of the additive; the conductivity...

  14. Preparation and Characterization of Nanocrystalline Thin Films of Al2O3 or TiO2 Doped Scandia Stabilized Zirconia Solid Electrolytes%Al2O3或TiO2掺杂的ScSZ固体电解质纳米晶薄膜的制备及表征

    Institute of Scientific and Technical Information of China (English)

    张亚文; 杨宇; 金舒; 田曙坚; 李国宝; 贾江涛; 廖春生; 严纯华

    2001-01-01

    Dense,crack-free and uniform nanocrystalline (Al2O3)0.10(Sc2O3)0.08(ZrO2)0.82and (Sc2O3)0.125(TiO2)0.175(ZrO2)0.70 thin films with thickness of 0.31 μm and 0.36 μm respectively on Si(100) substrate,have been successfully prepared by a Sol\\|Gel spin coating method.Cubic nanocrystals can be obtained at relatively low sintering temperature with an average grain size of about 47 nm and 51 nm respectively.The aluminia-doped ScSZ thins film are the same dense as the ScSZ thin films.However,there are a small amount of pinholes found in the microstructure of the titania-doped ScSZ films.%利用溶胶-凝胶旋涂法,在单晶硅基片(100)上分别制得了厚度约为0.31 μm的(Al2O3)0.10(Sc2O3)0.08(ZrO2)0.82和0.36 μm的(Sc2O3)0.125(TiO2)0.175(ZrO2)0.70固体电解质纳米晶薄膜。烧结实验结果表明,两种薄膜均在650℃以上开始晶化,温度越高,晶化越完全,在800℃可完全晶化;所得纳米晶颗粒呈纯的萤石结构立方相;铝和钛掺杂的纳米晶颗粒的平均大小分别为47和51 nm。铝掺杂的薄膜非常均匀致密,然而,钛掺杂的薄膜存在少量微气孔。

  15. Chemical stability of γ-butyrolactone-based electrolytes for aluminum electrolytic capacitors

    Science.gov (United States)

    Ue, Makoto; Takeda, Masayuki; Suzuki, Yoko; Mori, Shoichiro

    γ-Butyrolactone-based electrolytes have been used as the operating electrolytes for aluminum electrolytic capacitors. The chemical stability of these electrolytes at elevated temperatures has been examined by monitoring the decrease in their electrolytic conductivities. The deteriorated electrolytes were analyzed by gas and liquid chromatography and the conductivity decrease was directly correlated with the loss of acid components. In quaternary ammonium hydrogen maleate/γ-butyrolactone electrolytes, the maleate anion decomposed by decarboxylation resulting in a complex polymer containing polyester and polyacrylate structures. Quaternary ammonium benzoate/γ-butyrolactoneelectrolytes decomposed by SN2 reactions giving alkyi benzoates and trialkylamines. The deterioration of the carboxylate salt/γ-butyrolactone electrolytes was accelerated by electrolysis.

  16. Lithium ion conducting solid polymer blend electrolyte based on bio-degradable polymers

    Indian Academy of Sciences (India)

    Natarajan Rajeswari; Subramanian Selvasekarapandian; Moni Prabu; Shunmugavel Karthikeyan; C Sanjeeviraja

    2013-04-01

    Lithium ion conducting polymer blend electrolyte films based on poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) with different Mwt% of lithium nitrate (LiNO3) salt, using a solution cast technique, have been prepared. The polymer blend electrolyte has been characterized by XRD, FTIR, DSC and impedance analyses. The XRD study reveals the amorphous nature of the polymer electrolyte. The FTIR study confirms the complex formation between the polymer and salt. The shifts in g values of 70 PVA–30 PVP blend and 70 PVA–30 PVP with different Mwt% of LiNO3 electrolytes shown by DSC thermograms indicate an interaction between the polymer and the salt. The dependence of g and conductivity upon salt concentration has been discussed. The ion conductivity of the prepared polymer electrolyte has been found by a.c. impedance spectroscopic analysis. The PVA–PVP blend system with a composition of 70 wt% PVA: 30 wt% PVP exhibits the highest conductivity of 1.58 × 10-6 Scm-1 at room temperature. Polymer samples of 70 wt% PVA–30 wt% PVP blend with different molecular weight percentage of lithium nitrate with DMSO as solvent have been prepared and studied. High conductivity of 6.828 × 10-4 Scm-1 has been observed for the composition of 70 PVA:30 PVP:25 Mwt% of LiNO3 with low activation energy 0.2673 eV. The conductivity is found to increase with increase in temperature. The temperature dependent conductivity of the polymer electrolyte follows the Arrhenius relationship which shows hopping of ions in the polymer matrix. The relaxation parameters () and () of the complexes have been calculated by using loss tangent spectra. The mechanical properties of polymer blend electrolyte such as tensile strength, elongation and degree of swelling have been measured and the results are presented.

  17. Morphology and conductivity of in-situ PEO-LiClO4-TiO2 composite polymer electrolyte

    Institute of Scientific and Technical Information of China (English)

    PAN Chun-yue; FENG Qing; WANG Li-jun; ZHANG Qian; CHAO Meng

    2007-01-01

    PEO-LiClO4-TiO2 composite polymer electrolyte films were prepared. TiO2 was formed directly in matrix by hydrolysis and condensation reaction of tetrabutyl titanate. The crystallinity, morphology and ionic conductivity of composite polymer electrolyte films were examined by differential scanning calorimetry, scanning electron microscopy, atom force microscopy and alternating current impedance spectroscopy, respectively. The glass transition temperature and the crystallinity of composite polymer electrolytes are decreased compared with those of PEO-LiClO4 polymer electrolyte film. The results show that TiO2 particles are uniformly dispersed in PEO-LiClO4-5%TiO2 composite polymer electrolyte film. The maximal conductivity of 5.5×10-5 S/cm at 20 ℃ of PEO-LiClO4-TiO2 film is obtained at 5% mass fraction of TiO2.

  18. Influence of Al2O3 on the ionic conductivity of plasticized PVC-PEG blend polymer electrolytes

    Science.gov (United States)

    Ravindran, D.; Vickraman, P.

    2016-05-01

    Polymer electrolytes with PVC-PEG blend as host matrix and LiClO4 as dopant salt was prepared through conventional solution casting method. To enhance the conductivity propylene carbonate (PC) was used as plasticizer. The influence of ceramic filler Al2O3 on the conductivity of the electrolyte films were studied by varying the (PVC: Al2O3) ratio. The films were subjected to XRD, complex impedance analysis and SEM analysis. The XRD studies reveal a marginal increase in the amorphous phase of the electrolyte films due to the incorporation of filler. The AC impedance analysis shows the dependency of ionic conductivity on the content (wt %) of filler and exhibit a maximum at 4 wt% filler. The SEM analysis depicts the occurrence of phase separation in electrolyte which is attributed to the poor solubility of polymer PVC in the liquid electrolyte.

  19. Investigation of electrolyte electric discharge characteristics

    Science.gov (United States)

    Kirko, D. L.; Savjolov, A. S.

    2016-09-01

    The most important electrical characteristics of electrolyte electric discharge were investigated. The electric burning discharge was obtained with the help of different electrolytes. The spectral composition of the electric discharge electromagnetic radiation was determined, the plasma temperature was determined. The spectrum of the electric discharge high-frequency oscillations was calculated in the region v=10 kHz-80 MHz. The most appropriate modes of the electric burning discharge in different electrolytes were proposed.

  20. Solid electrolytes general principles, characterization, materials, applications

    CERN Document Server

    Hagenmuller, Paul

    1978-01-01

    Solid Electrolytes: General Principles, Characterization, Materials, Applications presents specific theories and experimental methods in the field of superionic conductors. It discusses that high ionic conductivity in solids requires specific structural and energetic conditions. It addresses the problems involved in the study and use of solid electrolytes. Some of the topics covered in the book are the introduction to the theory of solid electrolytes; macroscopic evidence for liquid nature; structural models; kinetic models; crystal structures and fast ionic conduction; interstitial motion in

  1. Fuel cell assembly with electrolyte transport

    Science.gov (United States)

    Chi, Chang V.

    1983-01-01

    A fuel cell assembly wherein electrolyte for filling the fuel cell matrix is carried via a transport system comprising a first passage means for conveying electrolyte through a first plate and communicating with a groove in a second plate at a first point, the first and second plates together sandwiching the matrix, and second passage means acting to carry electrolyte exclusively through the second plate and communicating with the groove at a second point exclusive of the first point.

  2. Solid-oxide fuel cell electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Bloom, I.D.; Hash, M.C.; Krumpelt, M.

    1991-12-31

    This invention is comprised of a solid-oxide electrolyte operable at between 600{degrees}C and 800{degrees}C and a method of producing the solid-oxide electrolyte. The solid-oxide electrolyte comprises a combination of a compound having a weak metal-oxygen interactions with a compound having stronger metal-oxygen interactions whereby the resulting combination has both strong and weak metal-oxygen interaction properties.

  3. Novel Electrolytes for Lithium Ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Lucht, Brett L. [Univ. of Rhode Island, Kingston, RI (United States). Dept. of Chemistry

    2014-12-12

    We have been investigating three primary areas related to lithium ion battery electrolytes. First, we have been investigating the thermal stability of novel electrolytes for lithium ion batteries, in particular borate based salts. Second, we have been investigating novel additives to improve the calendar life of lithium ion batteries. Third, we have been investigating the thermal decomposition reactions of electrolytes for lithium-oxygen batteries.

  4. U(Ⅳ) Preparation by Method of Electrolysis

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    U(Ⅳ) is prepared by electrolysis of U(Ⅵ) in nitric acid, as showed in Fig. 1. A circular-sheet osmotic film is fixed at the middle of electrolytic cell. Osmotic film can urge the electron transfering from one pole to another, but electrolyte

  5. Rebalancing electrolytes in redox flow battery systems

    Science.gov (United States)

    Chang, On Kok; Pham, Ai Quoc

    2014-12-23

    Embodiments of redox flow battery rebalancing systems include a system for reacting an unbalanced flow battery electrolyte with a rebalance electrolyte in a first reaction cell. In some embodiments, the rebalance electrolyte may contain ferrous iron (Fe.sup.2+) which may be oxidized to ferric iron (Fe.sup.3+) in the first reaction cell. The reducing ability of the rebalance reactant may be restored in a second rebalance cell that is configured to reduce the ferric iron in the rebalance electrolyte back into ferrous iron through a reaction with metallic iron.

  6. [FTIR investigation of new polymer solid electrolytes].

    Science.gov (United States)

    Yang, Shu-ting; Chen, Hong-jun; Dong, Hong-yu; Jia, Jun-hua; Cao, Zhao-xia

    2004-04-01

    The conductivity of the porous polymer solid electrolyte blended with PVDF and PMMA, which was made by a micro-wave hot-cross-linking method, reached 2.05 x 10(-3) S x cm(-1) at room temperature. The polymer solid electrolyte was analyzed and investigated by FTIR. The results show that the PVDF, PMMA and LiClO4 in the polymer solid electrolyte were not simply blended, but certain kind of effect existed which was strengthened only when the polymer solid electrolyte came into being.

  7. Electrodeposition of Fe powder from acid electrolytes

    Directory of Open Access Journals (Sweden)

    VESNA M. MAKSIMOVIC

    2008-08-01

    Full Text Available Polarization characteristics of the electrodeposition processes of Fe powders from sulfate and chloride electrolytes and the morphology of the obtained powders were investigated. The morphology depended on the anion presence in the electrolyte but not on the current density in the investigated range. A characteristic feature of the dendritic powder with cauliflower endings obtained from sulfate electrolyte is the presence of cone-like cavities and the crystallite morphology of the powders surface. On the other hand, Fe powders electrodeposited from chloride electrolyte appear in the form of agglomerates. A soap solution treatment applied as a method of washing and drying provides good protection from oxidation of the powders.

  8. Drug delivery device including electrolytic pump

    KAUST Repository

    Foulds, Ian G.

    2016-03-31

    Systems and methods are provided for a drug delivery device and use of the device for drug delivery. In various aspects, the drug delivery device combines a “solid drug in reservoir” (SDR) system with an electrolytic pump. In various aspects an improved electrolytic pump is provided including, in particular, an improved electrolytic pump for use with a drug delivery device, for example an implantable drug delivery device. A catalytic reformer can be incorporated in a periodically pulsed electrolytic pump to provide stable pumping performance and reduced actuation cycle.

  9. Electrolytic Passivation of Nitinol Shape Memory Alloy in Different Electrolytes

    Institute of Scientific and Technical Information of China (English)

    SU Xiang-dong; WANG Tian-min; HAO Wei-chang; HE Li

    2006-01-01

    The corrosion behavior of the nitinol alloy was studied in various corrosion media of different Cl- ion concentrations. The results demonstrate that the Cl- ion concentration has significant influences on the corrosion behavior of the nitinol alloy. In order to enhance the corrosion resistance, protective films were generated on the surface of the nitinol alloy by means of the electrochemical passivation method, for which five different electrolytic solutions were investigated. The surface analysis indicates full growth of all samples passivated in the different electrolytic solutions with layers, however, showing different morphological features. Without any defects like micro-cracks and pores, the surface of the samples passivated in the molybdate solution turns out smoother and denser than those passivated in other solutions. It is shown that the electro-chemical passivation will reduce Ni content but increase Ti content in the surface, reaching the Mole ratio of Ti:Ni = 9.01:1 on the outermost surface. Potentiodynamic polarization test demonstrates that the samples electrochemically passivated in the molybdate solution present a significant increase in breakdown potential due to titanium enrichment on the outermost surface.

  10. Interfacial behavior of polymer electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, John; Kerr, John B.; Han, Yong Bong; Liu, Gao; Reeder, Craig; Xie, Jiangbing; Sun, Xiaoguang

    2003-06-03

    Evidence is presented concerning the effect of surfaces on the segmental motion of PEO-based polymer electrolytes in lithium batteries. For dry systems with no moisture the effect of surfaces of nano-particle fillers is to inhibit the segmental motion and to reduce the lithium ion transport. These effects also occur at the surfaces in composite electrodes that contain considerable quantities of carbon black nano-particles for electronic connection. The problem of reduced polymer mobility is compounded by the generation of salt concentration gradients within the composite electrode. Highly concentrated polymer electrolytes have reduced transport properties due to the increased ionic cross-linking. Combined with the interfacial interactions this leads to the generation of low mobility electrolyte layers within the electrode and to loss of capacity and power capability. It is shown that even with planar lithium metal electrodes the concentration gradients can significantly impact the interfacial impedance. The interfacial impedance of lithium/PEO-LiTFSI cells varies depending upon the time elapsed since current was turned off after polarization. The behavior is consistent with relaxation of the salt concentration gradients and indicates that a portion of the interfacial impedance usually attributed to the SEI layer is due to concentrated salt solutions next to the electrode surfaces that are very resistive. These resistive layers may undergo actual phase changes in a non-uniform manner and the possible role of the reduced mobility polymer layers in dendrite initiation and growth is also explored. It is concluded that PEO and ethylene oxide-based polymers are less than ideal with respect to this interfacial behavior.

  11. Uso do processo sol-gel na obtenção de materiais híbridos organo-inorgânicos: preparação, caracterização e aplicação em eletrólitos de estado sólido Utilization of the sol-gel process to obtain organic-inorganic hybrid materials: preparation, characterization and application as solid state electrolytes

    Directory of Open Access Journals (Sweden)

    Rita A Zoppi

    1997-12-01

    Full Text Available Neste trabalho é descrita a preparação de materiais híbridos constituídos de um copolímero orgânico contendo segmentos óxido de etileno e de sílica. A rede inorgânica foi formada na solução polimérica a partir da hidrólise e condensação do tetraetoxisilano, TEOS. Como copolímero foi utilizado o poli(óxido de etileno-b-amida-6, PEBAX. Foram preparados também híbridos contendo perclorato de lítio, denominados aqui híbridos eletrólitos. Os materiais foram caracterizados por microscopia eletrônica de transmissão, ensaios de tensão-deformação, análise dinâmico-mecânica e difratometria de raios-X. Os sistemas PEBAX/TEOS/LiClO foram também caracterizados por espectroscopia de impedância eletroquímica e voltametria cíclica para avaliação de suas propriedades como eletrólito de estado sólido.In this work it was described the preparation of hybrid materials constituted by a organic copolymer, which contains ethylene oxide blocks, and silica. The inorganic network was formed by the hydrolysis and condensation of tetraethoxysilane, TEOS, into the polymeric solution. As a copolymer, it was used poly(ethylene oxide-b-amide-6, PEBAX. Hybrids containing lithium perchlorate, known as hybrid electrolytes, were also prepared. The materials were characterized by transmission electron microscopy, stress-strain tests, dynamic-mechanical analysis and X-ray diffractometry. The PEBAX/TEOS/LiClO4 systems were also characterized by electrochemical impedance spectroscopy and cyclic voltammetry to evaluate their properties as a solid state electrolyte.

  12. Ambient Temperature Hybrid Polymer Electrolyte Based on Pvk + Pvdf-Hfp for Lithium Batteries

    Science.gov (United States)

    Michael, M. S.; Prabaharan, S. R. S.

    2002-12-01

    Proposed herein is a new ambient temperature Li+ conducting PVDF-HFP-co-polymer based hybrid polymer electrolyte with polyvinyl carbozole (PVK) as additive. The addition of the latter provides high ambient temperature electrolytic conductivity (σi) 0.7 × 10-3S/cm with an ionic transference number of 0.6, besides providing the thermoplastic flexibility to the whole matrix. The membrane is found to exhibit a wide electrochemical potential window, >4.5V against Li/Li+. When prepared properly, the membrane is dry and free standing, yet totally suitable for lithium polymer rechargeable batteries. This paper presents the preparation, microstructure and electrochemical characteristics of this new hybrid polymeric membrane. Finally, the dry polymeric electrolyte membrane has been employed in a lithium polymer cell against LT-LiCo0.8Ni0.2O2 as positive electrode and its interfacial behavior and electrochemical cycling results are presented.

  13. Facile synthesis of polypyrrole nanofiber and its enhanced electrochemical performances in different electrolytes

    Directory of Open Access Journals (Sweden)

    C. K. Das

    2012-12-01

    Full Text Available A porous nanocomposite based on polypyrrole (PPy and sodium alginate (SA has been synthesized by easy, inexpensive, eco-friendly method. As prepared nanocomposite showed fibrillar morphology in transmission electron microscopic (TEM analysis. The average diameter of ~100 nm for the nanofibers was observed from scanning electron microscopic (SEM analysis. As prepared nanofiber, was investigated as an electrode material for supercapacitor application in different aqueous electrolyte solutions. PPy nanofiber showed enhanced electrochemical performances in 1M KCl solution as compared to 1M Na2SO4 solution. Maximum specific capacitance of 284 F/g was found for this composite in 1 M KCl electrolyte. It showed 76% specific capacitance retention after 600 cycles in 1 M KCl solution. Electrochemical Impedance Spectra showed moderate capacitive behavior of the composite in both the electrolytes. Further PPy nanofiber demonstrated higher thermal stability as compared to pure PPy.

  14. PE-g-MMA polymer electrolyte membrane for lithium polymer battery

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Kun; Hu, Xinguo; Yi, Tingfeng; Dai, Changsong [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)

    2006-10-25

    PE-g-MMA membranes with different degrees of grafting (DG) were prepared by electron beam radiation-induced graft copolymerization of methylmethacrylate (MMA) monomer onto polyethylene (PE) separator. The grafted membranes (GMs) were characterized using SEM, FTIR. The new polymer electrolytes based on GMs were prepared through immersion in a solution of LiPF{sub 6}-EC/DMC (1:1 by volume). It was found that the GMs with different DG exhibited the different uptake and retention ability of liquid electrolyte. Moreover, the ion conductivities of activated polymer electrolytes (APEs) were also found to vary with the different DG and reached a magnitude of 10{sup -3}Scm{sup -1} at the DG of 42%. Compared with those containing PE separators, the LiCoO{sub 2}-MCMB coin cells containing GMs demonstrated better cycle life and excellent rate performance. (author)

  15. PE-g-MMA polymer electrolyte membrane for lithium polymer battery

    Energy Technology Data Exchange (ETDEWEB)

    Gao Kun [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)]. E-mail: gaokun@hit.edu.cn; Hu Xinguo [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Yi Tingfeng [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Dai Changsong [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)

    2006-10-25

    PE-g-MMA membranes with different degrees of grafting (DG) were prepared by electron beam radiation-induced graft copolymerization of methylmethacrylate (MMA) monomer onto polyethylene (PE) separator. The grafted membranes (GMs) were characterized using SEM, FTIR. The new polymer electrolytes based on GMs were prepared through immersion in a solution of LiPF{sub 6}-EC/DMC (1:1 by volume). It was found that the GMs with different DG exhibited the different uptake and retention ability of liquid electrolyte. Moreover, the ion conductivities of activated polymer electrolytes (APEs) were also found to vary with the different DG and reached a magnitude of 10{sup -3} S cm{sup -1} at the DG of 42%. Compared with those containing PE separators, the LiCoO{sub 2}-MCMB coin cells containing GMs demonstrated better cycle life and excellent rate performance.

  16. Conductivity improvement of Ce0.8Gd0.2O19 solid electrolyte

    Institute of Scientific and Technical Information of China (English)

    Sebastian Molin; Maria Gazda; Piotr Jasinski

    2009-01-01

    Solid oxide fuel cells based on doped ceria electrolytes offer operating temperatures of ~600 ℃.During recent years much attention was aimed at successful powder preparation with high sinter activity and high conductivity.The properties of ceria electrolyte are very sensitive to impurities introduced during powder and electrolyte fabrication.One of the most successful and commercially available processes for the production of clean powders is based on the addition of several percent metallic cations that will react with impurities and segnegate into the triple points of grain boundaries.In this work the results obtained from doping of CGO20 by 2% Ca and prepared by different routes were presented.The way of introducing Ca seemed to play an important role.

  17. Impedance studies of a green blend polymer electrolyte based on PVA and Aloe-vera

    Science.gov (United States)

    Selvalakshmi, S.; Mathavan, T.; Vijaya, N.; Selvasekarapandian, Premalatha, M.; Monisha, S.

    2016-05-01

    The development of polymer electrolyte materials for energy generating and energy storage devices is a challenge today. A new type of blended green electrolyte based on Poly-vinyl alcohol (PVA) and Aloe-vera has been prepared by solution casting technique. The blending of polymers may lead to the increase in stability due to one polymer portraying itself as a mechanical stiffener and the other as a gelled matrix supported by the other. The prepared blend electrolytes were subjected to Ac impedance studies. It has been found out that the polymer film in which 1 gm of PVA was dissolved in 40 ml of Aloe-vera extract exhibits highest conductivity and its value is 3.08 × 10-4 S cm-1.

  18. Dense Nanostructured t-ZrO2 Coatings at Low Temperatures via Modified Emulsion Precipitation

    NARCIS (Netherlands)

    Woudenberg, F.C.M.; Sager, W.F.C.; Sibelt, N.G.M.; Verweij, H.

    2001-01-01

    Nanostructured coatings on metals, plastics, and textiles have numerous applications, for example, as antifogging and self-cleaning coatings as well as protective coatings against corrosion, heat, or wear. Here the preparation at low temperature of dense nanostructured tetragonal ZrO2 coatings via a

  19. Improved power conversion efficiency of dye-sensitized solar cells using side chain liquid crystal polymer embedded in polymer electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Woosum [Department of Chemistry Education, and Department of Frontier Materials Chemistry, and Institute for Plastic Information and Energy Materials, Pusan National University, Busan 609-735 (Korea, Republic of); Lee, Jae Wook, E-mail: jlee@donga.ac.kr [Department of Chemistry, Dong-A University, Busan 604-714 (Korea, Republic of); Gal, Yeong-Soon [Polymer Chemistry Lab, College of General Education, Kyungil University, Hayang 712-701 (Korea, Republic of); Kim, Mi-Ra, E-mail: mrkim2@pusan.ac.kr [Department of Polymer Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Jin, Sung Ho, E-mail: shjin@pusan.ac.kr [Department of Chemistry Education, and Department of Frontier Materials Chemistry, and Institute for Plastic Information and Energy Materials, Pusan National University, Busan 609-735 (Korea, Republic of)

    2014-02-14

    Side chain liquid crystal polymer (SCLCP) embedded in poly(vinylidenefluoride-co-hexafluoropropylene) (PVdF-co-HFP)-based polymer electrolytes (PVdF-co-HFP:side chain liquid crystal polymer (SCLCP)) was prepared for dye-sensitized solar cell (DSSC) application. The polymer electrolytes contained tetrabutylammonium iodide (TBAI), iodine (I{sub 2}), and 8 wt% PVdF-co-HFP in acetonitrile. DSSCs comprised of PVdF-co-HFP:SCLCP-based polymer electrolytes displayed enhanced redox couple reduction and reduced charge recombination in comparison to those of the conventional PVdF-co-HFP-based polymer electrolyte. The significantly increased short-circuit current density (J{sub sc}, 10.75 mA cm{sup −2}) of the DSSCs with PVdF-co-HFP:SCLCP-based polymer electrolytes afforded a high power conversion efficiency (PCE) of 5.32% and a fill factor (FF) of 0.64 under standard light intensity of 100 mW cm{sup −2} irradiation of AM 1.5 sunlight. - Highlights: • We developed the liquid crystal polymer embedded on polymer electrolyte for DSSCs. • We fabricated the highly efficient DSSCs using polymer electrolyte. • The best PCE achieved for P1 is 5.32% using polymer electrolyte.

  20. Thiourea incorporated poly(ethylene oxide) as transparent gel polymer electrolyte for dye sensitized solar cell applications

    Science.gov (United States)

    Pavithra, Nagaraj; Velayutham, David; Sorrentino, Andrea; Anandan, Sambandam

    2017-06-01

    A new series of transparent gel polymer electrolytes are prepared by adding various weight percent of thiourea coupled with poly(ethylene oxide) for the application of dye-sensitized solar cells. Coupling of thiourea in the presence of iodine undergoes dimerization reaction to produce formamidine disulfide. Fourier Transform Infrared spectroscopy shows that the interactions of thiourea and formamidine disulfide with electronegative ether linkage of poly(ethylene oxide) results in conformational changes of gel polymer electrolytes. Electrochemical impedance spectroscopy and linear sweep voltammetry experiments reveal an increment in ionic conductivity and tri-iodide diffusion coefficient, for thiourea modified gel polymer electrolytes. Finally, the prepared electrolytes are used as a redox mediator in dye-sensitized solar cells and the photovoltaic properties were studied. Apart from transparency, the gel polymer electrolytes with thiorurea show higher photovoltaic properties compared to bare gel polymer electrolyte and a maximum photocurrent efficiency of 7.17% is achieved for gel polymer electrolyte containing 1 wt% of thiourea with a short circuit current of 11.79 mA cm-2 and open circuit voltage of 834 mV. Finally, under rear illumination, almost 90% efficiency is retained upon compared to front illumination.

  1. Dye-sensitized solar cells assembled with composite gel polymer electrolytes containing nanosized Al2O3 particles.

    Science.gov (United States)

    Jeon, Nawon; Kim, Dong-Won

    2013-12-01

    Polymeric ionic liquid, poly(1-methyl 3-(2-acryloyloxy propyl) imidazolium iodide) (PMAPII) containing iodide ions is synthesized and used as a matrix polymer for preparing the composite polymer electrolytes. The composite gel polymer electrolytes are prepared by utilizing PMAPII, organic solvent containing redox couple and aluminum oxide nanoparticle for application in dye-sensitized solar cells (DSSCs). PMAPII is highly compatible with organic solvents and thus there is no phase separation between the PMAPII and organic solvents. This makes it be possible to directly solidify the liquid electrolyte in the cell and maintain good interfacial contacts between the electrolyte and electrodes. The addition of 10 wt.% Al2O3 nanoparticle to gel polymer electrolyte provides the most desirable environment for ionic transport, resulting in the improvement of the photovoltaic performance of DSSC. The quasi-solid-state DSSC assembled with optimized composite gel polymer electrolyte containing 10 wt.% Al2O3 nanoparticle exhibits a relatively high conversion efficiency of 6.51% under AM 1.5 illumination at 100 mA cm(-2) and better stability than DSSC with liquid electrolyte.

  2. Investigation on poly (vinylidene fluoride) based gel polymer electrolytes

    Indian Academy of Sciences (India)

    S Rajendran; P Sivakumar; Ravi Shanker Babu

    2006-12-01

    An investigation is carried out on gel polymer electrolytes consisting of poly (vinylidene fluoride) (PVdF) as a host polymer, lithium perchlorate (LiClO4), lithium triflate (LiCF3SO3) as salts and mixture of ethylene carbonate (EC) and propylene carbonate (PC) as plasticizers. Polymer thin films were prepared by solvent casting technique and the obtained films were subjected to different characterizations, to confirm their structure, complexation and thermal changes. X-ray diffraction revealed that the salts and plasticizers disrupted the crystalline nature of PVdF based polymer electrolytes and converted them into an amorphous phase. TG/DTA studies showed the thermal stability of the polymer electrolytes. The role of interaction between polymer hosts on conductivity is discussed using the results of a.c. impedance studies. Room temperature (28°C) conductivity of 2.786 × 10-3 Scm-1 was observed in PVdF (24)–EC/PC (68)–LiCF3SO3 (2)/LiClO4 (6) polymer system.

  3. Electrochemical behaviors of novel composite polymer electrolytes for lithium batteries

    Institute of Scientific and Technical Information of China (English)

    Guorong Chen; Pengfei Shi; Yongping Bai; Taibing Fan

    2004-01-01

    A novel composite polymer electrolyte was prepared by blending an appropriate amount of LiClO4 and 10% (mass fraction)fumed SiO2 with the block copolymer of poly (ethylene oxide) (PEO) synthesized by poly (ethylene glycol) (PEG) 400 and CH2Cl2.The ionic conductivity, electrochemical stability, interfacial characteristic and thermal behavior of the composite polymer electrolytewere studied by the measurements of AC impedance spectroscopy, linear sweep voltammetry and differential scanning calorimetry(DSC), respectively. The glass transition temperature acts as a function of salt concentration, which increases with the LiClO4 content.Lewis acid-base model interaction mechanism was introduced to interpret the interactive relation between the filled fumed SiO2 andthe lithium salt in the composite polymer electrolyte. Over the salt concentration range and the measured temperature, the maximumionic conductivity of the composite polymer electrolyte (10-4.41 S/cm) appeared at EO/Li=25 (mole ratio) and 30℃, and the begin-ning oxidative degradation potential versus Li beyond 5 V.

  4. Advanced Polymer Electrolytes for High-energy-density Power Sources

    Institute of Scientific and Technical Information of China (English)

    D. Golodnitsky; E. Livshits; R. Kovarsky; E. Peled

    2005-01-01

    @@ 1Introduction The preparation of highly controlled thin films of lithium ion conducting organic materials is becoming a challenging but rewarding goal in view of obtaining high-performance technological devices like solid-state polymer batteries and capacitors. The classical polymer electrolyte consists of organic macromolecules (usually polyether polymer) that are doped with inorganic (typically lithium) salts. Poly(ethylene oxide) (PEO) is the most commonly employed polymer in PEs because of the peculiar array in the (-CH2-CH2-O-)n chain providing the ability to solvate low-lattice-energy lithium salts. For three decades the major research attention was focused on amorphous polymer electrolytes in the belief that ionic conductivity occurs in a manner somewhat analogous to gas diffusion through polymer membranes. Segmental motion of the polymer chains continuously creates free volume, into which the ions migrate, and this process allows ions to progress across the electrolyte. Such a view was established by a number of experiments, and denied the possibility of ionic conductivity in crystalline polymer phases. This concept has been recently overturned by our group, demonstrating that conductivity comes about as a result of permanent conducting pathways for the movement of ions.

  5. Plasma electrolytic oxidation of AMCs

    Science.gov (United States)

    Morgenstern, R.; Sieber, M.; Lampke, T.

    2016-03-01

    Aluminum Matrix Composites (AMCs) consisting of high-strength alloys and ceramic reinforcement phases exhibit a high potential for security relevant lightweight components due to their high specific mechanical properties. However, their application as tribologically stressed components is limited because of their susceptibility against fatigue wear and delamination wear. Oxide ceramic protective coatings produced by plasma electrolytic oxidation (PEO) can solve these problems and extend the possible applications of AMCs. The substrate material was powder metallurgically processed using alloy EN AW 2017 and SiC or Al2O3 particles. The influence of material properties like particle type, size and volume fraction on coating characteristics is clarified within this work. An alkaline silicate electrolyte was used to produce PEO coatings with technically relevant thicknesses under bipolar-pulsed current conditions. Coating properties were evaluated with regard to morphology, chemical composition, hardness and wear resistance. The particle type proved to have the most significant effect on the coating properties. Whereas compactness and thickness are not deteriorated by the incorporation of thermodynamically stable alumina particles, the decomposition of silica particles during the PEO processes causes an increase of the porosity. The higher silica particle content decreases also the coating thickness and hardness, which leads in particular to reduction of the wear resistance of the PEO coatings. Finally, different approaches for the reduction of the coating porosity of silica reinforced AMCs are discussed.

  6. Plasma electrolytic oxidation of metals

    Directory of Open Access Journals (Sweden)

    Stojadinović Stevan

    2013-01-01

    Full Text Available In this lecture results of the investigation of plasma electrolytic oxidation (PEO process on some metals (aluminum, titanium, tantalum, magnesium, and zirconium were presented. Whole process involves anodizing metals above the dielectric breakdown voltage where numerous micro-discharges are generated continuously over the coating surface. For the characterization of PEO process optical emission spectroscopy and real-time imaging were used. These investigations enabled the determination of electron temperature, electron number density, spatial density of micro-discharges, the active surface covered by micro-discharges, and dimensional distribution of micro-discharges at various stages of PEO process. Special attention was focused on the results of the study of the morphology, chemical, and phase composition of oxide layers obtained by PEO process on aluminum, tantalum, and titanium in electrolytes containing tungsten. Physicochemical methodes: atomic force microscopy (AFM, scanning electron microscopy (SEM-EDS, x-ray diffraction (XRD, x-ray photoelectron spectroscopy (XPS, and Raman spectroscopy served as tools for examining obtained oxide coatings. Also, the application of the obtained oxide coatings, especially the application of TiO2/WO3 coatings in photocatalysis, were discussed.

  7. O electrolyte for bio-application

    Science.gov (United States)

    Naddaf, M.; Almariri, A.

    2014-09-01

    Porous silicon (PS) has been prepared in the dark by anodic etching of n+-type (111) silicon substrate in a HF:HCl:C2H5OH:H2O2:H2O electrolyte. The processed PS layer is characterized by means of photoluminescence (PL) spectroscopy, scanning electron microscope (SEM), water contact angle (CA) measurements, Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and micro-Raman scattering. The CA of fresh PS layer is found to be ~142°. On aging at ambient conditions, the CA decreases gently to reach ~133° after 3 month, and then it is stabilized for a prolonged time of aging. The visible PL emission from the PS layer also exhibits a good stability against aging time. The FTIR and XPS measurements and analysis show that the stable aged PS layer has rather SiO2-rich surface. The micro/nanostructure nature of the PS layer is revealed from SEM and micro-Raman results and correlated to CA results. Stable hydrophobic surface of oxidized PS layer is attractive for bio-applications. The efficiency of the produced PS layers as an entrapping template for specific immobilization of IgG2a antibody via physical absorption process is demonstrated.

  8. Ion Transport and Discharge Characteristics of Polymer Blend (PVP/PVA) Electrolyte Films Doped with Potassium Iodide

    Science.gov (United States)

    Umadevi, C.; Mohan, K. R.; Achari, V. B. S.; Sharma, A. K.; Rao, V. V. R. N.

    2010-12-01

    Solid polymer blend electrolyte films based on PVP/PVA complexed with KI were prepared by the solution cast technique. Various experimental techniques such as electrical conductivity and transport number measurement were used to characterize the polymer electrolyte films. Electrochemical cells with the polymer electrolytes (PVP+PVA+KI) were fabricated in the configuration K/(PVP+PVA+KI)/ (I2+C+electrode). The discharge characteristics of the cells were studied under a constant load of 100 KΩ. The open-circuit voltage, short-circuit current and discharge time for the plateau region are measured. Several other cell parameters were evaluated and are reported.

  9. Ionic conductivity and transport properties of poly(vinylidene fluoride-co-hexafluoropropylene)-based solid polymer electrolytes

    Science.gov (United States)

    Abreha, Merhawi; Subrahmanyam, A. R.; Siva Kumar, J.

    2016-08-01

    Polymer electrolytes containing poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) and various concentrations of lithium triflate were prepared to determine the optimal polymer-salt composition for maximum ionic conductivity. Complex formation was ascertained from X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) studies. The conductivity measurements reveal that the ionic conductivity of the polymer electrolytes containing various salt concentrations increases with temperature and obeys the Arrhenius rule. It is found that the electrolyte containing 25 wt.% of lithium triflate exhibits the highest room temperature conductivity. Moreover, Ionic transference measurements show predominance of ionic motion.

  10. Effect of The Addition of PEG and PVA Polymer for Gel Electrolytes in Dye-Sensitized Solar Cell (DSSC) with Chlorophyll as Dye Sensitizer

    Science.gov (United States)

    Seni, Ramadhanti S.; Puspitasari, Nurrisma; Endarko

    2017-07-01

    Dye-sensitized Solar Cell (DSSC) is a third-generation solar cell that consists of a working electrode, electrolyte and counter electrode. One of the most important parts of DSSC is an electrolyte that roles as a medium and regenerates the electron transport of electrons in the dye. However, the liquid electrolyte has a lack of stability in long-term use and easily evaporate or leak in DSSC. Therefore, this study aims to investigate an effect of the addition of polymer material such as PEG 1000, 4000 and PVA 60000 for fabricating a gel electrolyte to solve the problems of liquid electrolyte. The synthesized TiO2 nanoparticles used in this study was prepared using co-precipitation (CPT) method which produces TiO2 anatase phase with a crystal size of 11.1 nm. DSSC has been successfully conducted and analyzed to evaluate its performance. The results showed that the efficiency of DSSC cells using gel electrolyte prepared with PVA 60000 was better than a liquid electrolyte, PEG 1000, 4000, with the efficiency could be obtained at 0.083, 0.018, 0.033, and 0.054%, respectively. The results demonstrated that the addition PEG and/or PVA could be enhanced the performance of DSSC due to gel electrolyte produced current and voltage more stable compared to the liquid electrolyte.

  11. Capacitance of Ti3C2Tx MXene in ionic liquid electrolyte

    Science.gov (United States)

    Lin, Zifeng; Barbara, Daffos; Taberna, Pierre-Louis; Van Aken, Katherine L.; Anasori, Babak; Gogotsi, Yury; Simon, Patrice

    2016-09-01

    Ti3C2Tx MXene, a two-dimensional (2D) early transition metal carbide, has shown an extremely high volumetric capacitance in aqueous electrolytes, but in a narrow voltage window (less than 1.23 V). The utilization of MXene materials in ionic liquid electrolytes with a large voltage window has never been addressed. Here, we report the preparation of the Ti3C2Tx MXene ionogel film by vacuum filtration for use as supercapacitor electrodes operating in 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TFSI) neat ionic liquid electrolyte. Due to the disordered structure of the Ti3C2Tx hydrogel film and a stable spacing after vacuum drying, achieved through ionic liquid electrolyte immersion of the Ti3C2Tx hydrogel film, the Ti3C2Tx surface became accessible to EMI+ and TFSI- ions. A capacitance of 70 F g-1 together with a large voltage window of 3 V was obtained at a scan rate of 20 mV s-1 in neat EMI-TFSI electrolyte. The electrochemical signature indicates a capacitive behavior even at a high scan rate (500 mV s-1) and a high power performance. This work opens up the possibilities of using MXene materials with various ionic liquid electrolytes.

  12. Gelation Behavior of Poly (Vinylidene Fluoride )-based Gel Polymer Electrolyte

    Institute of Scientific and Technical Information of China (English)

    WANG Biao-bing; GU Li-xia

    2006-01-01

    Poly ( vinylidene fluoride ) ( PVdF )-based gel polymer electrolytes with various compositions were prepared by solution casting technique. The kinetics of gelation was analyzed via the correlation between the apparent gelation rate and concentration of PVdF at a given temperature.Combination the results of the kinetics of gelation and the DSC study, it revealed that the phase separation was the major behavior and the fibrils were the major junction joints of the three-dimensional network even in the ease the concentration of PVdF was higher than 25 wt%. The porous surface observed by ESEM also reflected that the phase separation took place during the gelation.

  13. Conductivity Studies of the Plasticized-Poly(methylmethacrylate) Polymer Electrolytes

    Institute of Scientific and Technical Information of China (English)

    A.Ahmad; Z.Osman

    2007-01-01

    1 Results In this work,five systems of polymethylmethacrylate (PMMA)-based polymer electrolytes films have been prepared by the solution casting technique.The five systems are the (PMMA-EC) system,the (PMMA + PC) system,the (PMMA+LiCF3SO3) system,the ([PMMA+EC]+LiCF3SO3) system and the ([PMMA+PC]+LiCF3SO3) system.The conductivity for each system is characterized using impedance spectroscopy.The conductivity of the pure PMMA,the (PMMA+EC) system and the (PMMA+PC) system at room temperature is 2.37×10-9,3...

  14. Progress on the Electrolytes for Dye-sensitized Solar Cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    1 Results The development of a new type of solar cell has been promoted by public concern about pollution and energy consumption.Since the prototype of a dye-sensitized solar cell (DSC) was reported in 1991 by M.Gratzel,it has aroused intensive interest over the past decade due to its low cost and simple preparation procedure.The typical cell is a sandwiched structure consisting of a dye-sensitized TiO2 electrode,a platinized counter electrode and a filled redox couple electrolyte between the electrodes...

  15. Nuclear Probing of Dense Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Richard Petrasso

    2007-02-14

    The object of inertial confinement fusion (ICF) is to compress a fuel capsule to a state with high enough density and temperature to ignite, starting a self-sustaining fusion burn that consumes much of the fuel and releases a large amount of energy. The national ICF research program is trying to reach this goal, especially through experiments at the OMEGA laser facility of the University of Rochester Laboratory of Laser Energetics (LLE), planned experiments at the National Ignition Facility (NIF) under construction at the Lawrence Livermore National Laboratory (LLNL), and experimental and theoretical work at other national laboratories. The work by MIT reported here has played several important roles in this national program. First, the development of new and improved charged-particle-based plasma diagnostics has allowed the gathering of new and unique diagnostic information about the implosions of fuel capsules in ICF experiments, providing new means for evaluating experiments and for studying capsule implosion dynamics. Proton spectrometers have become the standard for evaluating the mass assembly in compressed capsules in experiments at OMEGA; the measured energy downshift of either primary or secondary D3He fusion protons to determines the areal density, or ?R, of imploded capsules. The Proton Temporal Diagnostic measures the time history of fusion burn, and multiple proton emission imaging cameras reveal the 3-D spatial distribution of fusion burn. A new compact neutron spectrometer, for measuring fusion yield, is described here for the first time. And of especially high importance to future work is the Magnetic Recoil Spectrometer (MRS), which is a neutron spectrometer that will be used to study a range of important performance parameters in future experiments at the NIF. A prototype is currently being prepared for testing at OMEGA, using a magnet funded by this grant. Second, MIT has used these diagnostic instruments to perform its own physics experiments

  16. Dense Membranes for Anode Supported all Perovskite IT-SOFCs

    Energy Technology Data Exchange (ETDEWEB)

    Rambabu Bobba

    2006-09-14

    determine the % of solubility in the crystal lattice of perovskite, apatites. Various electrode and electrolyte material compositions were prepared and characterized by XRD, SEM, XPS and electron microprobe. The material compositions were selected based on their thermo-physical properties to achieve compatibility with each other in ideal fuel cell operating conditions. The series of electrode materials investigated are LaGa{sub 1-x}M{sub x}O{sub 3} (M = Mn, Mg, x = 0.1), LaCr{sub 1-x}M{sub x}O{sub 3} (M = Mn, Mg, Co, x=0.1), LaNi{sub 1-x}Fe{sub x}O{sub 3} (0 < x < 0.6) and Gd{sub 1-x}M{sub x}CoO{sub 3} (M=Ca, x=0.1). Attempts were made to prepare proton-conducting perovskites of SrCe{sub 1-x} M{sub x}O{sub 3} (M= Dy, Eu, Er, Tb, x=0.1) by using sonochemical and hydrothermal technique followed by microwave sintering processes. These compositions were prepared characterized by XRD, TEM, SEM and electrical conductivity of the pellets was measured. The interest of low temperature proton conducting electrolyte is to replace the well known oxide ion conducting solid electrolyte in SOFCs, thereby reducing the operating temperature of SOFC to lower temperature (i.e 400-600 C) and named it as PC-SOFC (proton conducting-solid oxide fuel cell).

  17. Modeling for CVD of Solid Oxide Electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Starr, T.L.

    2002-09-18

    Because of its low thermal conductivity, high thermal expansion and high oxygen ion conductivity yttria-stabilized zirconia (YSZ) is the material of choice for high temperature electrolyte applications. Current coating fabrication methods have their drawbacks, however. Air plasma spray (APS) is a relatively low-cost process and is suitable for large and relatively complex shapes. it is difficult to produce uniform, relatively thin coatings with this process, however, and the coatings do not exhibit the columnar microstructure that is needed for reliable, long-term performance. The electron-beam physical vapor deposition (EB-PVD) process does produce the desirable microstructure, however, the capital cost of these systems is very high and the line-of-sight nature of the process limits coating uniformity and the ability to coat large and complex shapes. The chemical vapor deposition (CVD) process also produces the desirable columnar microstructure and--under proper conditions--can produce uniform coatings over complex shapes. CVD has been used for many materials but is relatively undeveloped for oxides, in general, and for zirconia, in particular. The overall goal of this project--a joint effort of the University of Louisville and Oak Ridge National Laboratory (ORNL)--is to develop the YSZ CVD process for high temperature electrolyte applications. This report describes the modeling effort at the University of Louisville, which supports the experimental work at ORNL. Early work on CVD of zirconia and yttria used metal chlorides, which react with water vapor to form solid oxide. Because of this rapid gas-phase reaction the water generally is formed in-situ using the reverse water-gas-shift reaction or a microwave plasma. Even with these arrangements gas-phase nucleation and powder formation are problems when using these precursors. Recent efforts on CVD of zirconia and YSZ have focused on use of metal-organic precursors (MOCVD). These are more stable in the gas

  18. Structure and electrochemical properties of composite polymer electrolyte based on poly vinylidene fluoride-hexafluoropropylene/titania-poly(methyl methacrylate) for lithium-ion batteries

    Science.gov (United States)

    Cao, Jiang; Wang, Li; Fang, Mou; He, Xiangming; Li, Jianjun; Gao, Jian; Deng, Lingfeng; Wang, Jianlong; Chen, Hong

    2014-01-01

    Titania-poly(methyl methacrylate) (PMMA) organic-inorganic hybrid material is synthesized via in situ polymerization. The hybrid material is employed to prepare poly vinylidene fluoride-hexafluoropropylene (PVdF-HFP) composite polymer electrolyte. The effect of the hybrid material is investigated by SEM, TG-DSC, AC impedance and charge/discharge cycling tests. The results demonstrate that the inorganic-organic hybrid material as additive increases the porosity, pore size and electrolyte uptake of the PVdF-HFP composite polymer electrolyte membrane, so that the ionic conductivity of the composite polymer electrolyte membrane is improved. The performance enhancement of the composite polymer electrolyte is confirmed by an electrochemical test using LiCoO2/Li cells in the voltage range of 2.75-4.4 V. This study shows that titania-PMMA hybrid material is a promising additive for PVDF-HFP composite polymer electrolyte for Li-ion batteries.

  19. Structural and ionic conductivity studies of electrospun polymer blend P(VdF-co-HFP)/PMMA electrolyte membrane for lithium battery application

    Energy Technology Data Exchange (ETDEWEB)

    Padmaraj, O.; Satyanarayana, N., E-mail: nallanis2011@gmail.com [Department of Physics, Pondicherry University, Pondicherry 605 014 (India); Venkateswarlu, M. [R& D, Amara Raja Batteries Ltd., Karakambadi 517 520 (India)

    2015-06-24

    A novel fibrous polymer blend [(100-x) % P(VdF-co-HFP)/x % PMMA, x = 10, 20, 30, 40, 50] electrolyte membranes were prepared by electrospinning technique. Structural, thermal and surface morphology of all the compositions of electrospun polymer blend membranes were studied by using XRD, DSC & SEM. The newly developed five different compositions of polymer blend fibrous electrolyte membranes were obtained by soaking in an electrolyte solution contains 1M LiPF{sub 6} in EC: DEC (1:1,v/v). The wet-ability and conductivity of all the compositions of polymer blend electrolyte membranes are evaluated through electrolyte uptake and impedance measurements. The polymer blend [90% P(VdF-co-HFP)/10% PMMA] electrolyte membrane showed good wet-ability and high conductivity (1.788 × 10{sup −3} Scm{sup −1}) at room temperature.

  20. Fabrication of anode-supported zirconia thin film electrolyte based core-shell particle structure for intermediate temperature solid oxide fuel cells

    Institute of Scientific and Technical Information of China (English)

    Peng Li; John T.S.Irvinen

    2013-01-01

    With a view to produce intermediate temperature SOFCs, yttria and scandia doped zirconia with a core-shell structure was prepared, then an anode supported fuel cell was fabricated by a spray method. The influences of the scandia content in the electrolyte and atmosphere conditions used in the testing experiments on phase composition, microstructure and fuel cell performance were investigated. The electrolyte was composed of cubic and tetragonal phases and SEM pictures revealed very fine grain sizes and a smooth surface of the electrolyte film, though some defects were observed in samples with high Scandia content. Coating scandia on partially stabilized zirconium particles improves both ionic conductivity of the electrolyte and power density of the fuel cell distinctly below 750 1C. Anodes were pre-sintered at 1200 1C before co-sintering with the electrolyte film to ensure that the shrinkage percentage was close to that of the electrolyte during co-sintering, avoiding warping of cell.

  1. Synthesis of polymer electrolyte membranes from cellulose acetate/poly(ethylene oxide)/LiClO{sub 4} for lithium ion battery application

    Energy Technology Data Exchange (ETDEWEB)

    Nurhadini,, E-mail: nur-chem@yahoo.co.id; Arcana, I Made, E-mail: arcana@chem.itb.ac.id [Inorganic and Physical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Institiut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132 (Indonesia)

    2015-09-30

    This study was conducted to determine the effect of cellulose acetate on poly(ethylene oxide)-LiClO{sub 4} membranes as the polymer electrolyte. Cellulose acetate is used as an additive to increase ionic conductivity and mechanical property of polymer electrolyte membranes. The increase the percentage of cellulose acetate in membranes do not directly effect on the ionic conductivity, and the highest ionic conductivity of membranes about 5,7 × 10{sup −4} S/cm was observed in SA/PEO/LiClO{sub 4} membrane with cellulose ratio of 10-25% (w/w). Cellulose acetate in membranes increases mechanical strength of polymer electrolyte membranes. Based on TGA analysis, this polymer electrolyte thermally is stable until 270 °C. The polymer electrolyte membrane prepared by blending the cellulose acetate, poly(ethylene oxide), and lithium chlorate could be potentially used as a polymer electrolyte for lithium ion battery application.

  2. Synthesis of polymer electrolyte membranes from cellulose acetate/poly(ethylene oxide)/LiClO4 for lithium ion battery application

    Science.gov (United States)

    Nurhadini, Arcana, I. Made

    2015-09-01

    This study was conducted to determine the effect of cellulose acetate on poly(ethylene oxide)-LiClO4 membranes as the polymer electrolyte. Cellulose acetate is used as an additive to increase ionic conductivity and mechanical property of polymer electrolyte membranes. The increase the percentage of cellulose acetate in membranes do not directly effect on the ionic conductivity, and the highest ionic conductivity of membranes about 5,7 × 10-4 S/cm was observed in SA/PEO/LiClO4 membrane with cellulose ratio of 10-25% (w/w). Cellulose acetate in membranes increases mechanical strength of polymer electrolyte membranes. Based on TGA analysis, this polymer electrolyte thermally is stable until 270 °C. The polymer electrolyte membrane prepared by blending the cellulose acetate, poly(ethylene oxide), and lithium chlorate could be potentially used as a polymer electrolyte for lithium ion battery application.

  3. The charge transport in polymeric gel electrolytes

    CERN Document Server

    Reiche, A

    2001-01-01

    The aim of the present thesis consisted in the study of the charge transport in gel electrolytes, which were obtained by photopolymerization of oligo(ethylene glycol) sub n -dimethacrylates with n=3, 9, and 23, and the survey of structure and property relations for the optimization of the electrolyte composition. The pressure dependence of the electric conductivity was measured. (HSI)

  4. Microporous polymer electrolyte based on PVDF-PEO

    Institute of Scientific and Technical Information of China (English)

    LI Jian; XI Jingyu; SONG Qing; TANG Xiaozhen

    2005-01-01

    @@ Since Wright et al.[1] found that the complex of PEO/alkali metals salt had the ability of ionic conductivity in 1973, in-depth studies have been carried out about various polymer electrolytes, which were applied to replacing the liquid electrolytes in lithium ion battery[2,3]. At present, polymer electrolytes mainly include three kinds: dry polymer electrolytes, gel polymer electrolytes and microporous polymer electrolytes.

  5. Polybenzimidazole and sulfonated polyhedral oligosilsesquioxane composite membranes for high temperature polymer electrolyte membrane fuel cells

    DEFF Research Database (Denmark)

    Aili, David; Allward, Todd; Alfaro, Silvia Martinez

    2014-01-01

    Composite membranes based on poly(2,2′(m-phenylene)-5,5́bibenzimidazole) (PBI) and sulfonated polyhedral oligosilsesquioxane (S-POSS) with S-POSS contents of 5 and 10wt.% were prepared by solution casting as base materials for high temperature polymer electrolyte membrane fuel cells. With membranes...

  6. Characterization of plasticized PMMA–LiBF4 based solid polymer electrolytes

    Indian Academy of Sciences (India)

    S Rajendran; T Uma

    2000-02-01

    Polymer electrolyte films prepared from poly(methyl methacrylate) and LiBF4 with different concentrations of plasticizer (DBP) are described. The formation of polymer–salt complex has been confirmed by FTIR spectral studies. The temperature dependence of conductivity of polymer films seems to obey the VTF relation. Values of conductivities of the polymer complexes are presented and discussed.

  7. Injection of photoelectrons into dense argon gas

    CERN Document Server

    Borghesani, A F

    2010-01-01

    The injection of photoelectrons in a gaseous or liquid sample is a widespread technique to produce a cold plasma in a weakly--ionized system in order to study the transport properties of electrons in a dense gas or liquid. We report here the experimental results of photoelectron injection into dense argon gas at the temperatureT=142.6 K as a function of the externally applied electric field and gas density. We show that the experimental data can be interpreted in terms of the so called Young-Bradbury model only if multiple scattering effects due to the dense environment are taken into account when computing the scattering properties and the energetics of the electrons.

  8. Atomic Layer Deposition of the Solid Electrolyte Garnet Li7La3Zr2O12

    Energy Technology Data Exchange (ETDEWEB)

    Kazyak, Eric; Chen, Kuan-Hung; Wood, Kevin N.; Davis, Andrew L.; Thompson, Travis; Bielinski, Ashley R.; Sanchez, Adrian; Wang, Xiang; Wang, Chongmin; Sakamoto, Jeff S.; Dasgupta, Neil P.

    2017-04-25

    Lithium solid electrolytes are a promising platform for achieving high energy density, long-lasting, and safe rechargeable batteries, which could have widespread societal impact. In particular, the ceramic oxide garnet Li7La3Zr2O12 (LLZO) has been shown to be a promising electrolyte due to its stability and high ionic conductivity. Two major challenges for commercialization are manufacturing of thin layers and creating stable, low-impedance, interfaces with both anode and cathode materials. Atomic Layer Deposition (ALD) has recently been shown as a potential method for depositing both solid electrolytes and interfacial layers to improve the stability and performance at electrode-electrolyte interfaces in battery systems. Herein we present the first reported ALD process for LLZO, demonstrating the ability to tune composition within the amorphous film and anneal to achieve the desired cubic garnet phase. Formation of the cubic phase was observed at temperatures as low as 555°C, significantly lower than is required for bulk processing. Additionally, challenges associated with achieving a dense garnet phase due to substrate reactivity, morphology changes and Li loss under the necessary high temperature annealing are quantified via in situ synchrotron diffraction.

  9. Proton Conducting Polymer Electrolytes and Its Applications

    Institute of Scientific and Technical Information of China (English)

    S. Selvasekarapandian; G. Hirankumar; R. Baskaran; M.S. Bhuvaneswari

    2005-01-01

    @@ 1Introduction Proton conducting solid polymer electrolytes have been extensively studied due to their potential applications in electrochemical devices such as batteries, super capacitors, electrochromic windows, sensors etc[1,2]Many researchers have studied the behaviour of inorganic based polymer electrolytes as proton conductors and their applications in solid state devices at room temperature[3]. But, inorganic acid doped electrolytes have some serious disadvantages like corrosion towards the electrode and hazardous. Hence, there is need for searching new electrolyte which is stable towards the electrode. It has been reported that the ammonium salts which behaves like alkali metal salt are good dopant to the polymer matrix[4, 5] for the development of proton conducting polymer electrolyte. The proton conductors based on poly (ethylene oxide)[6], poly (ethylene succinate)[7], poly (ethylene glycol)[8], as host matrix doped with ammonium salt have already been reported.

  10. The Interplay of Al and Mg Speciation in Advanced Mg Battery Electrolyte Solutions.

    Science.gov (United States)

    See, Kimberly A; Chapman, Karena W; Zhu, Lingyang; Wiaderek, Kamila M; Borkiewicz, Olaf J; Barile, Christopher J; Chupas, Peter J; Gewirth, Andrew A

    2016-01-13

    Mg batteries are an attractive alternative to Li-based energy storage due to the possibility of higher volumetric capacities with the added advantage of using sustainable materials. A promising emerging electrolyte for Mg batteries is the magnesium aluminum chloride complex (MACC) which shows high Mg electrodeposition and stripping efficiencies and relatively high anodic stabilities. As prepared, MACC is inactive with respect to Mg deposition; however, efficient Mg electrodeposition can be achieved following an electrolytic conditioning process. Through the use of Raman spectroscopy, surface enhanced Raman spectroscopy, (27)Al and (35)Cl nuclear magnetic resonance spectroscopy, and pair distribution function analysis, we explore the active vs inactive complexes in the MACC electrolyte and demonstrate the codependence of Al and Mg speciation. These techniques report on significant changes occurring in the bulk speciation of the conditioned electrolyte relative to the as-prepared solution. Analysis shows that the active Mg complex in conditioned MACC is very likely the [Mg2(μ-Cl)3·6THF](+) complex that is observed in the solid state structure. Additionally, conditioning creates free Cl(-) in the electrolyte solution, and we suggest the free Cl(-) adsorbs at the electrode surface to enhance Mg electrodeposition.

  11. Investigation on the corrosion behaviour and microstructure of 2024-T3 Al alloy treated via plasma electrolytic oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Fadaee, Hossein; Javidi, Mehdi, E-mail: mjavidi@yahoo.com

    2014-08-01

    Highlights: • Plasma electrolytic oxidation used to improve corrosion resistance of 2024-T3 alloy. • A conventional DC source with low applied voltage was considered for PEO. • Use of glycerin was effective in enhancement of corrosion resistance. • The surface morphology indicated coatings have a dense structure without cracking. • Degradation of coatings with immersion time was investigated. - Abstract: Plasma electrolytic oxidation treatment was performed on 2024-T3 aluminium alloy in a simple and inexpensive electrolyte. It was found that treatment time of 30 min resulted in the most noble corrosion potential and lowest corrosion current density. The surface and cross-sectional morphology indicated that the coating has a dense structure without any cracking. Furthermore, the result of X-ray diffraction analysis indicated that the coating was formed mainly from α-Al{sub 2}O{sub 3}, γ-Al{sub 2}O{sub 3}, Al{sub 3.21}Si{sub 0.47} and small amounts of amorphous phases. The presence of glycerine in the electrolyte composition resulted in not only stabilising the solution but also improving the corrosion resistance.

  12. Solid polymer electrolyte from phosphorylated chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Fauzi, Iqbal, E-mail: arcana@chem.itb.ac.id; Arcana, I Made, E-mail: arcana@chem.itb.ac.id [Inorganic and Physical Chemistry Research Groups, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    2014-03-24

    Recently, the need of secondary battery application continues to increase. The secondary battery which using a liquid electrolyte was indicated had some weakness. A solid polymer electrolyte is an alternative electrolytes membrane which developed in order to replace the liquid electrolyte type. In the present study, the effect of phosphorylation on to polymer electrolyte membrane which synthesized from chitosan and lithium perchlorate salts was investigated. The effect of the component’s composition respectively on the properties of polymer electrolyte, was carried out by analyzed of it’s characterization such as functional groups, ion conductivity, and thermal properties. The mechanical properties i.e tensile resistance and the morphology structure of membrane surface were determined. The phosphorylation processing of polymer electrolyte membrane of chitosan and lithium perchlorate was conducted by immersing with phosphoric acid for 2 hours, and then irradiated on a microwave for 60 seconds. The degree of deacetylation of chitosan derived from shrimp shells was obtained around 75.4%. Relative molecular mass of chitosan was obtained by viscometry method is 796,792 g/mol. The ionic conductivity of chitosan membrane was increase from 6.33 × 10{sup −6} S/cm up to 6.01 × 10{sup −4} S/cm after adding by 15 % solution of lithium perchlorate. After phosphorylation, the ionic conductivity of phosphorylated lithium chitosan membrane was observed 1.37 × 10{sup −3} S/cm, while the tensile resistance of 40.2 MPa with a better thermal resistance. On the strength of electrolyte membrane properties, this polymer electrolyte membrane was suggested had one potential used for polymer electrolyte in field of lithium battery applications.

  13. Surface Morphology and Microstructure of Zinc Deposit From Imidazole with Zinc Chloride Low Temperature Molten Salt Electrolyte in The Presence of Aluminium Chloride

    Directory of Open Access Journals (Sweden)

    Shanmugasigamani Srinivasan, M. Selvam

    2013-07-01

    Full Text Available Low temperature molten salts have variety of applications in organic synthesis, catalytic processing, batteries and electrode position due to their air and water stability. They have wide potential window for their applications in voltage and temperature and hence there is a possibility to deposit metals which could not be deposited from aqueous electrolytes. Our aim and scope of our research was to deposit zinc from low temperature molten salt electrolyte (LTMS containing zinc salt in the presence of aluminium chloride at different current densities and to qualify the nature of deposits. We could identify the effect of current density on the deposit at low temperature molten salt electrolyte by analysing the nature of deposits using different instrumental techniques. Compact, adherent, dense fine grained deposits of zinc with average grain size of 40-150 nm could be obtained from low temperature molten salt electrolyte. (LTMS

  14. Enhancing Chemical Stability of Electroplated Cu Films by Engineering Electrolyte Chemistry and Twinning Structure

    Science.gov (United States)

    Yang, Chih-Jie; Huang, Chun-Lung; Liao, Chien-Neng

    2015-07-01

    The effects of an electrolyte additive and twinning structure on the corrosion characteristics of electroplated Cu films have been investigated. Four different Cu films were individually deposited with and without benzotriazole (BTA) in the electrolyte using the direct-current (DC) and pulsed-current (PC) plating techniques. The Cu films plated with BTA additive showed improved corrosion resistance according to electrochemical polarization testing and postetching morphological inspection. Moreover, the PC-plated films that had dense nanoscale twin boundaries appeared to have higher chemical stability than the DC-plated ones. It is proposed that the presence of twin-modified grain boundary segments suppresses corrosion along the grain boundary network and improves the corrosion resistance of electroplated Cu films.

  15. High rate lithium-sulfur battery enabled by sandwiched single ion conducting polymer electrolyte

    Science.gov (United States)

    Sun, Yubao; Li, Gai; Lai, Yuanchu; Zeng, Danli; Cheng, Hansong

    2016-02-01

    Lithium-sulfur batteries are highly promising for electric energy storage with high energy density, abundant resources and low cost. However, the battery technologies have often suffered from a short cycle life and poor rate stability arising from the well-known “polysulfide shuttle” effect. Here, we report a novel cell design by sandwiching a sp3 boron based single ion conducting polymer electrolyte film between two carbon films to fabricate a composite separator for lithium-sulfur batteries. The dense negative charges uniformly distributed in the electrolyte membrane inherently prohibit transport of polysulfide anions formed in the cathode inside the polymer matrix and effectively blocks polysulfide shuttling. A battery assembled with the composite separator exhibits a remarkably long cycle life at high charge/discharge rates.

  16. Electrolyte and glucose contents of ripe and unripe coconut liquid as source of oral rehydration solution

    Directory of Open Access Journals (Sweden)

    A O Adegoke

    2012-04-01

    Full Text Available Summary: Electrolyte and glucose contents of 20 ripe and 20 unripe coconuts were analysed along with a commercially prepared oral rehydration solution using flame photometry for sodium, potassium and back titration method for bicarbonate estimation while glucose oxidase method was carried out for glucose estimation. The unripe coconut liquid had mean+ SEM of sodium (mmol/L 40.08 + 3.21, potassium (mmol/l 24.06 + 0.89, bicarbonate (mmol/l 1.48 + 0.20 and glucose (mmol/l 26.30 + 0.21 while the ripe coconut liquidhad sodium (mmol/l 24.60+ 1.36, Potassium (mmol/l 15.48 + 0.23, bicarbonate (mmol/l 0.80 + 0.18 and glucose concentration (mmol/l of 1.68 + 0.51 respectively. There was significant difference in the electrolyte content of the ripe and unripe coconut liquid (P< 0.05. The commercially prepared ORS had sodium (mmol/l 90.00 + 0.1, Potassium (mmol/l 20.00 + 0.1, bicarbonate (mmol/l 29.00 + 0.1 and glucose concentration (mmol/l of 111.00 + 0.1 respectively. The electrolyte and glucose contents of the ripe coconut was found not to meet minimum WHO standard of glucose concentration of 111mmol/l, sodium 90mmol/l, Potassium 20mmol/l and bicarbonate concentration of 30mmol/l for ORS. The Potassium concentration of the unripe coconut was higher than minimum WHO standard for ORS. However, the use of coconut liquid for rehydration cannot be recommended on the basis of its glucose and electrolyte composition.Industrial relevance: Coconut water is often used as an alternative solution for oral rehydration, particularly in regions where mothers' knowledge of oral rehydration is lacking. There has been no differentiation in the type of coconut water used for the purpose of replacing lost electrolytes; hence the electrolytes lost due to dehydration will not be replaced if the source of rehydration doesn’t contain the proper concentration of electrolytes. The study highlighted the deficiencies in the ripe and unripe coconut water as a rehydration source

  17. Electrolytic exfoliation of graphite in water with multifunctional electrolytes: en route towards high quality, oxide-free graphene flakes.

    Science.gov (United States)

    Munuera, J M; Paredes, J I; Villar-Rodil, S; Ayán-Varela, M; Martínez-Alonso, A; Tascón, J M D

    2016-02-07

    Electrolytic--usually referred to as electrochemical--exfoliation of graphite in water under anodic potential holds enormous promise as a simple, green and high-yield method for the mass production of graphene, but currently suffers from several drawbacks that hinder its widespread adoption, one of the most critical being the oxidation and subsequent structural degradation of the carbon lattice that is usually associated with such a production process. To overcome this and other limitations, we introduce and implement the concept of multifunctional electrolytes. The latter are amphiphilic anions (mostly polyaromatic hydrocarbons appended with sulfonate groups) that play different relevant roles as (1) an intercalating electrolyte to trigger exfoliation of graphite into graphene flakes, (2) a dispersant to afford stable aqueous colloidal suspensions of the flakes suitable for further use, (3) a sacrificial agent to prevent graphene oxidation during exfoliation and (4) a linker to promote nanoparticle anchoring on the graphene flakes, yielding functional hybrids. The implementation of this strategy with some selected amphiphiles even furnishes anodically exfoliated graphenes of a quality similar to that of flakes produced by direct, ultrasound- or shear-induced exfoliation of graphite in the liquid phase (i.e., almost oxide- and defect-free). These high quality materials were used for the preparation of catalytically efficient graphene-Pt nanoparticle hybrids, as demonstrated by model reactions (reduction of nitroarenes). The multifunctional performance of these electrolytes is also discussed and rationalized, and a mechanistic picture of their oxidation-preventing ability is proposed. Overall, the present results open the prospect of anodic exfoliation as a competitive method for the production of very high quality graphene flakes.

  18. Effect of Mg doping and sintering temperature on structural and morphological properties of samarium-doped ceria for IT-SOFC electrolyte

    Science.gov (United States)

    Ahmad, Syed Ismail; Mohammed, Tasneem; Bahafi, Amal; Suresh, Madireddy Buchi

    2017-06-01

    Samples of Sm and Mg co-doped ceria electrolyte of Ce1- x Sm x- y Mg y O2- δ ( x = 0.2; y = 0.00, 0.05, 0.1, 0.15, and 0.175) were synthesized by sol-gel process. The prepared samples were sintered at 1100 and 1400 °C for 4 h. The bulk densities were measured by Archimedes method. XRD measurements indicate that the synthesized samples were in single-phase cubic fluorite structure (space group Fm3m). The cell parameters decrease with the concentration of Mg, and 2 θ values slightly shift towards right. The particle sizes obtained were between 7.14 and 17.44 nm. The sintered sample achieved 95% of theoretical density. FTIR spectra of samples sintered at 1400 °C indicates weak interactions between 3550-3400 cm-1 and 1600-1300 cm-1 are attributed to O-H stretching modes and strong bonds 850-450 cm-1 are assigned to characteristic Ce-O vibrations. The surface morphology and chemical composition were analyzed by SEM and EDS, SEM micrographs show spherical faceted grains, and the samples were crack free, dense material with some pores on surface which are inconsistent with density results. The average grain size obtained was 0.5 μm. Particle size obtained by TEM was in agreement with that obtained by XRD. The high-density ceria co-doped ceramic can be used as electrolyte in SOFC.

  19. High Performance Cathodes for Solid Oxide Fuel Cells Prepared by Infiltration of La0.6Sr0.4CoO32d into Gd-Doped Ceria

    DEFF Research Database (Denmark)

    Samson, Alfred Junio; Søgaard, Martin; Knibbe, Ruth

    2011-01-01

    Cathodes prepared by infiltration of La0.6Sr0.4CoO3d (LSC40) into a porous Ce0.9Gd0.1O1.95 (CGO10) backbone have been developed for low temperature solid oxide fuel cells. The CGO10 backbone has been prepared by screen printing a CGO10 ink on both sides of a 180 m dense CGO10 electrolyte...... and the number of infiltrations. The cathode polarization resistance was measured using electrochemical impedance spectroscopy on symmetrical cells in ambient air, while the resulting structures were characterized by scanning electron microscopy (SEM) and high temperature X-ray diffraction (HT-XRD). The firing...

  20. Electrolytic exfoliation of graphite in water with multifunctional electrolytes: en route towards high quality, oxide-free graphene flakes

    Science.gov (United States)

    Munuera, J. M.; Paredes, J. I.; Villar-Rodil, S.; Ayán-Varela, M.; Martínez-Alonso, A.; Tascón, J. M. D.

    2016-01-01

    Electrolytic - usually referred to as electrochemical - exfoliation of graphite in water under anodic potential holds enormous promise as a simple, green and high-yield method for the mass production of graphene, but currently suffers from several drawbacks that hinder its widespread adoption, one of the most critical being the oxidation and subsequent structural degradation of the carbon lattice that is usually associated with such a production process. To overcome this and other limitations, we introduce and implement the concept of multifunctional electrolytes. The latter are amphiphilic anions (mostly polyaromatic hydrocarbons appended with sulfonate groups) that play different relevant roles as (1) an intercalating electrolyte to trigger exfoliation of graphite into graphene flakes, (2) a dispersant to afford stable aqueous colloidal suspensions of the flakes suitable for further use, (3) a sacrificial agent to prevent graphene oxidation during exfoliation and (4) a linker to promote nanoparticle anchoring on the graphene flakes, yielding functional hybrids. The implementation of this strategy with some selected amphiphiles even furnishes anodically exfoliated graphenes of a quality similar to that of flakes produced by direct, ultrasound- or shear-induced exfoliation of graphite in the liquid phase (i.e., almost oxide- and defect-free). These high quality materials were used for the preparation of catalytically efficient graphene-Pt nanoparticle hybrids, as demonstrated by model reactions (reduction of nitroarenes). The multifunctional performance of these electrolytes is also discussed and rationalized, and a mechanistic picture of their oxidation-preventing ability is proposed. Overall, the present results open the prospect of anodic exfoliation as a competitive method for the production of very high quality graphene flakes.Electrolytic - usually referred to as electrochemical - exfoliation of graphite in water under anodic potential holds enormous promise