WorldWideScience

Sample records for anodic materials

  1. Anodic Materials for Electrocatalytic Ozone Generation

    OpenAIRE

    Yun-Hai Wang; Qing-Yun Chen

    2013-01-01

    Ozone has wide applications in various fields. Electrocatalytic ozone generation technology as an alternative method to produce ozone is attractive. Anodic materials have significant effect on the ozone generation efficiency. The research progress on anodic materials for electrocatalytic ozone generation including the cell configuration and mechanism is addressed in this review. The lead dioxide and nickel-antimony-doped tin dioxide anode materials are introduced in detail, including their st...

  2. New High-Energy Nanofiber Anode Materials

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiangwu; Fedkiw, Peter; Khan, Saad; Huang, Alex; Fan, Jiang

    2013-11-15

    The overall goal of the proposed work was to use electrospinning technology to integrate dissimilar materials (lithium alloy and carbon) into novel composite nanofiber anodes, which simultaneously had high energy density, reduced cost, and improved abuse tolerance. The nanofiber structure allowed the anodes to withstand repeated cycles of expansion and contraction. These composite nanofibers were electrospun into nonwoven fabrics with thickness of 50 μm or more, and then directly used as anodes in a lithium-ion battery. This eliminated the presence of non-active materials (e.g., conducting carbon black and polymer binder) and resulted in high energy and power densities. The nonwoven anode structure also provided a large electrode-electrolyte interface and, hence, high rate capacity and good lowtemperature performance capability. Following are detailed objectives for three proposed project periods. • During the first six months: Obtain anodes capable of initial specific capacities of 650 mAh/g and achieve ~50 full charge/discharge cycles in small laboratory scale cells (50 to 100 mAh) at the 1C rate with less than 20 percent capacity fade; • In the middle of project period: Assemble, cycle, and evaluate 18650 cells using proposed anode materials, and demonstrate practical and useful cycle life (750 cycles of ~70% state of charge swing with less than 20% capacity fade) in 18650 cells with at least twice improvement in the specific capacity than that of conventional graphite electrodes; • At the end of project period: Deliver 18650 cells containing proposed anode materials, and achieve specific capacities greater than 1200 mAh/g and cycle life longer than 5000 cycles of ~70% state of charge swing with less than 20% capacity fade.

  3. Anodic titania films as anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Titania thin films were prepared through the anodisation of titanium metal in a 1.0 M sulphuric acid solution at 80 oC utilising a series of pulsed dc constant currents of increasing magnitude. Films were then tested as a potential anode material for lithium batteries using a variety of techniques. Electrochemical testing revealed that the films (3.8 cm2) offered good rate capabilities affording a constant capacity of 48 μAh for a constant current of 10 μA which decreased to 25 μAh on increasing the current to 1250 μA. Cyclic voltammetry was conducted over a range of scan rates from which capacitive currents were examined and rate constants, transfer coefficients and diffusion coefficients calculated. Electrochemical impedance spectroscopy was conducted over six potentials in the range 0.1-2.7 V with the experimental data successfully modelled using an equivalent circuit with the notation R(Q(RW))C. TEM observation of focussed ion beam milled cross-sections showed significant structural differences between the as-anodised film and those cycled in a lithium battery. Raman spectroscopy showed that the films had an anatase character that transformed into an unidentified lithium-containing, titanate phase on cycling. Based on a film thickness of 100 nm, and assuming density of 4 g cm-3 such films offered a stable capacity of 316 mAh g-1

  4. Reactivity of Anode Raw  Materials and Anodes for Production of Aluminium

    OpenAIRE

    Engvoll, Marianne Aanvik

    2002-01-01

    In the Hall-Héroult process for primary production of aluminium, a considerable amount of anode carbon is lost through unwanted gasification in air and CO2. The carbon gasification reactions are catalyzed by a number of inorganic impurities normally present in the anodes. Some of these impurities follow the anode raw materials while others are introduced during the anode manufacturing process.The aim of this work is to obtain a fundamental knowledge of how the bath compounds: AlF3, Al2O3, NaF...

  5. Nanocomposite anode materials for sodium-ion batteries

    Science.gov (United States)

    Manthiram, Arumugam; Kim Il, Tae; Allcorn, Eric

    2016-06-14

    The disclosure relates to an anode material for a sodium-ion battery having the general formula AO.sub.x--C or AC.sub.x--C, where A is aluminum (Al), magnesium (Mg), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), zirconium (Zr), molybdenum (Mo), tungsten (W), niobium (Nb), tantalum (Ta), silicon (Si), or any combinations thereof. The anode material also contains an electrochemically active nanoparticles within the matrix. The nanoparticle may react with sodium ion (Na.sup.+) when placed in the anode of a sodium-ion battery. In more specific embodiments, the anode material may have the general formula M.sub.ySb-M'O.sub.x--C, Sb-MO.sub.x--C, M.sub.ySn-M'C.sub.x--C, or Sn-MC.sub.x--C. The disclosure also relates to rechargeable sodium-ion batteries containing these materials and methods of making these materials.

  6. Na-Ion Battery Anodes: Materials and Electrochemistry.

    Science.gov (United States)

    Luo, Wei; Shen, Fei; Bommier, Clement; Zhu, Hongli; Ji, Xiulei; Hu, Liangbing

    2016-02-16

    The intermittent nature of renewable energy sources, such as solar and wind, calls for sustainable electrical energy storage (EES) technologies for stationary applications. Li will be simply too rare for Li-ion batteries (LIBs) to be used for large-scale storage purposes. In contrast, Na-ion batteries (NIBs) are highly promising to meet the demand of grid-level storage because Na is truly earth abundant and ubiquitous around the globe. Furthermore, NIBs share a similar rocking-chair operation mechanism with LIBs, which potentially provides high reversibility and long cycling life. It would be most efficient to transfer knowledge learned on LIBs during the last three decades to the development of NIBs. Following this logic, rapid progress has been made in NIB cathode materials, where layered metal oxides and polyanionic compounds exhibit encouraging results. On the anode side, pure graphite as the standard anode for LIBs can only form NaC64 in NIBs if solvent co-intercalation does not occur due to the unfavorable thermodynamics. In fact, it was the utilization of a carbon anode in LIBs that enabled the commercial successes. Anodes of metal-ion batteries determine key characteristics, such as safety and cycling life; thus, it is indispensable to identify suitable anode materials for NIBs. In this Account, we review recent development on anode materials for NIBs. Due to the limited space, we will mainly discuss carbon-based and alloy-based anodes and highlight progress made in our groups in this field. We first present what is known about the failure mechanism of graphite anode in NIBs. We then go on to discuss studies on hard carbon anodes, alloy-type anodes, and organic anodes. Especially, the multiple functions of natural cellulose that is used as a low-cost carbon precursor for mass production and as a soft substrate for tin anodes are highlighted. The strategies of minimizing the surface area of carbon anodes for improving the first-cycle Coulombic efficiency are

  7. Carbon Fiber as Anode Material for Cathodic Prevention in Cementitious Materials

    OpenAIRE

    Zhang, Emma Qingnan; Tang, Luping; Zack, Thomas

    2016-01-01

    Cathodic prevention (CPre) technique is a promising method and has been used for the past two decades to prevent steel from corrosion in concrete structures. However, wide application of this technique has been restricted due to high costs of anode materials. In order to lower the cost and further improve this technique, carbon fiber composite anode has been introduced as an alternative anode material with affordable price and other outstanding properties. This paper presents the study of usi...

  8. Carbon Cryogel Silicon Composite Anode Materials for Lithium Ion Batteries

    Science.gov (United States)

    Woodworth James; Baldwin, Richard; Bennett, William

    2010-01-01

    A variety of materials are under investigation for use as anode materials in lithium-ion batteries, of which, the most promising are those containing silicon. 10 One such material is a composite formed via the dispersion of silicon in a resorcinol-formaldehyde (RF) gel followed by pyrolysis. Two silicon-carbon composite materials, carbon microspheres and nanofoams produced from nano-phase silicon impregnated RF gel precursors have been synthesized and investigated. Carbon microspheres are produced by forming the silicon-containing RF gel into microspheres whereas carbon nano-foams are produced by impregnating carbon fiber paper with the silicon containing RF gel to create a free standing electrode. 1-4,9 Both materials have demonstrated their ability to function as anodes and utilize the silicon present in the material. Stable reversible capacities above 400 mAh/g for the bulk material and above 1000 mAh/g of Si have been observed.

  9. Nanocomposite anode materials for sodium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Manthiram, Arumugam; Kim Il, Tae; Allcorn, Eric

    2016-06-14

    The disclosure relates to an anode material for a sodium-ion battery having the general formula AO.sub.x--C or AC.sub.x--C, where A is aluminum (Al), magnesium (Mg), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), zirconium (Zr), molybdenum (Mo), tungsten (W), niobium (Nb), tantalum (Ta), silicon (Si), or any combinations thereof. The anode material also contains an electrochemically active nanoparticles within the matrix. The nanoparticle may react with sodium ion (Na.sup.+) when placed in the anode of a sodium-ion battery. In more specific embodiments, the anode material may have the general formula M.sub.ySb-M'O.sub.x--C, Sb-MO.sub.x--C, M.sub.ySn-M'C.sub.x--C, or Sn-MC.sub.x--C. The disclosure also relates to rechargeable sodium-ion batteries containing these materials and methods of making these materials.

  10. Optimization and Domestic Sourcing of Lithium Ion Battery Anode Materials

    Energy Technology Data Exchange (ETDEWEB)

    Wood, III, D. L.; Yoon, S. [A123 Systems, Inc.

    2012-10-25

    The purpose of this Cooperative Research and Development Agreement (CRADA) between ORNL and A123Systems, Inc. was to develop a low-temperature heat treatment process for natural graphite based anode materials for high-capacity and long-cycle-life lithium ion batteries. Three major problems currently plague state-of-the-art lithium ion battery anode materials. The first is the cost of the artificial graphite, which is heat-treated well in excess of 2000°C. Because of this high-temperature heat treatment, the anode active material significantly contributes to the cost of a lithium ion battery. The second problem is the limited specific capacity of state-of-the-art anodes based on artificial graphites, which is only about 200-350 mAh/g. This value needs to be increased to achieve high energy density when used with the low cell-voltage nanoparticle LiFePO4 cathode. Thirdly, the rate capability under cycling conditions of natural graphite based materials must be improved to match that of the nanoparticle LiFePO4. Natural graphite materials contain inherent crystallinity and lithium intercalation activity. They hold particular appeal, as they offer huge potential for industrial energy savings with the energy costs essentially subsidized by geological processes. Natural graphites have been heat-treated to a substantially lower temperature (as low as 1000-1500°C) and used as anode active materials to address the problems described above. Finally, corresponding graphitization and post-treatment processes were developed that are amenable to scaling to automotive quantities.

  11. High capacity anode materials for lithium ion batteries

    Science.gov (United States)

    Lopez, Herman A.; Anguchamy, Yogesh Kumar; Deng, Haixia; Han, Yongbon; Masarapu, Charan; Venkatachalam, Subramanian; Kumar, Suject

    2015-11-19

    High capacity silicon based anode active materials are described for lithium ion batteries. These materials are shown to be effective in combination with high capacity lithium rich cathode active materials. Supplemental lithium is shown to improve the cycling performance and reduce irreversible capacity loss for at least certain silicon based active materials. In particular silicon based active materials can be formed in composites with electrically conductive coatings, such as pyrolytic carbon coatings or metal coatings, and composites can also be formed with other electrically conductive carbon components, such as carbon nanofibers and carbon nanoparticles. Additional alloys with silicon are explored.

  12. Porous graphene for high capacity lithium ion battery anode material

    Science.gov (United States)

    Wang, Yusheng; Zhang, Qiaoli; Jia, Min; Yang, Dapeng; Wang, Jianjun; Li, Meng; Zhang, Jing; Sun, Qiang; Jia, Yu

    2016-02-01

    Based on density functional theory calculations, we studied the Li dispersed on porous graphene (PG) for its application as Li ion battery anode material. The hybridization of Li atoms and the carbon atoms enhanced the interaction between Li atoms and the PG. With holes of specific size, the PG can provide excellent mobility with moderate barriers of 0.37-0.39 eV. The highest Li storage composite can be LiC0.75H0.38 which corresponds to a specific capacity of 2857.7 mA h/g. Both specific capacity and binding energy are significantly larger than the corresponding value of graphite, this makes PG a promising candidate for the anode material in battery applications. The interactions between the Li atoms and PG can be easily tuned by an applied strain. Under biaxial strain of 16%, the binding energy of Li to PG is increased by 17% compared to its unstrained state.

  13. ANODE CATALYST MATERIALS FOR USE IN FUEL CELLS

    DEFF Research Database (Denmark)

    2002-01-01

    Catalyst materials having a surface comprising a composition M¿x?/Pt¿3?/Sub; wherein M is selected from the group of elements Fe, Co, Rh and Ir; or wherein M represent two different elements selected from the group comprising Fe, CO, Rh, Ir, Ni, Pd, CU, Ag, Au and Sn; and wherein Sub represents a...... substrate material selected from Ru and Os; the respective components being present within specific ranges, display improved properties for use inanodes for low-temperature fuel cell anodes for PENFC fuel cells and direct methanol fuel cells....

  14. Graphene composites as anode materials in lithium-ion batteries

    Science.gov (United States)

    Mazar Atabaki, M.; Kovacevic, R.

    2013-03-01

    Since the world of mobile phones and laptops has significantly altered by a big designer named Steve Jobs, the electronic industries have strived to prepare smaller, thinner and lower weight products. The giant electronic companies, therefore, compete in developing more efficient hardware such as batteries used inside the small metallic or polymeric frame. One of the most important materials in the production lines is the lithium-based batteries which is so famous for its ability in recharging as many times as a user needs. However, this is not an indication of being long lasted, as many of the electronic devices are frequently being used for a long time. The performance, chemistry, safety and above all cost of the lithium ion batteries should be considered when the design of the compounds are at the top concern of the engineers. To increase the efficiency of the batteries a combination of graphene and nanoparticles is recently introduced and it has shown to have enormous technological effect in enhancing the durability of the batteries. However, due to very high electronic conductivity, these materials can be thought of as preparing the anode electrode in the lithiumion battery. In this paper, the various approaches to characterize different types of graphene/nanoparticles and the process of preparing the anode for the lithium-ion batteries as well as their electrical properties are discussed.

  15. Material and Energy Flows in the Production of Cathode and Anode Materials for Lithium Ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States); James, Christine [Michigan State Univ., East Lansing, MI (United States); Gaines, Linda [Argonne National Lab. (ANL), Argonne, IL (United States); Gallagher, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States); Dai, Qiang [Argonne National Lab. (ANL), Argonne, IL (United States); Kelly, Jarod C. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    The Greenhouse gases, Regulated Emissions and Energy use in Transportation (GREET) model has been expanded to include four new cathode materials that can be used in the analysis of battery-powered vehicles: lithium nickel cobalt manganese oxide (LiNi0.4Co0.2Mn0.4O2 [NMC]), lithium iron phosphate (LiFePO4 [LFP]), lithium cobalt oxide (LiCoO2 [LCO]), and an advanced lithium cathode (0.5Li2MnO3∙0.5LiNi0.44Co0.25Mn0.31O2 [LMR-NMC]). In GREET, these cathode materials are incorporated into batteries with graphite anodes. In the case of the LMR-NMC cathode, the anode is either graphite or a graphite-silicon blend. Lithium metal is also an emerging anode material. This report documents the material and energy flows of producing each of these cathode and anode materials from raw material extraction through the preparation stage. For some cathode materials, we considered solid state and hydrothermal preparation methods. Further, we used Argonne National Laboratory’s Battery Performance and Cost (BatPaC) model to determine battery composition (e.g., masses of cathode, anode, electrolyte, housing materials) when different cathode materials were used in the battery. Our analysis concluded that cobalt- and nickel-containing compounds are the most energy intensive to produce.

  16. Pulsed laser deposited Si on multilayer graphene as anode material for lithium ion batteries

    OpenAIRE

    Gouri Radhakrishnan; Paul M. Adams; Brendan Foran; Michael V. Quinzio; Miles J. Brodie

    2013-01-01

    Pulsed laser deposition and chemical vapor deposition were used to deposit very thin silicon on multilayer graphene (MLG) on a nickel foam substrate for application as an anode material for lithium ion batteries. The as-grown material was directly fabricated into an anode without a binder, and tested in a half-cell configuration. Even under stressful voltage limits that accelerate degradation, the Si-MLG films displayed higher stability than Si-only electrodes. Post-cycling images of the anod...

  17. Modified natural graphite as anode material for lithium ion batteries

    Science.gov (United States)

    Wu, Y. P.; Jiang, C.; Wan, C.; Holze, R.

    A concentrated nitric acid solution was used as an oxidant to modify the electrochemical performance of natural graphite as anode material for lithium ion batteries. Results of X-ray photoelectron spectroscopy, electron paramagnetic resonance, thermogravimmetry, differential thermal analysis, high resolution electron microscopy, and measurement of the reversible capacity suggest that the surface structure of natural graphite was changed, a fresh dense layer of oxides was formed. Some structural imperfections were removed, and the stability of the graphite structure increased. These changes impede decomposition of electrolyte solvent molecules, co-intercalation of solvated lithium ions and movement of graphene planes along the a-axis direction. Concomitantly, more micropores were introduced, and thus, lithium intercalation and deintercalation were favored and more sites were provided for lithium storage. Consequently, the reversible capacity and the cycling behavior of the modified natural graphite were much improved by the oxidation. Obviously, the liquid-solid oxidation is advantageous in controlling the uniformity of the products.

  18. Metal carbonates as anode materials for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Lianyi; Ma, Rui; Wu, Kaiqiang; Shui, Miao; Lao, Mengmeng; Wang, Dongjie; Long, Nengbing; Ren, Yuanlong; Shu, Jie, E-mail: sergio_shu@hotmail.com

    2013-12-25

    Highlights: •Metal carbonates are probable anode materials for lithium ion batteries. •CoCO{sub 3}/C composite can deliver an initial discharge capacity of 2096.6 mAh g{sup −1} . •Co, Li{sub 2}CO{sub 3}, Li{sub 2}O, and low-valence carbon are final lithiated products for CoCO{sub 3}. -- Abstract: Six metal carbonates (Li{sub 2}CO{sub 3}, Na{sub 2}CO{sub 3}, SrCO{sub 3}, BaCO{sub 3}, K{sub 2}CO{sub 3}, CoCO{sub 3}) are tested and compared as anode materials for lithium ion batteries. The electrochemical results show that only CoCO{sub 3} is electrochemically active material and can deliver a high initial capacity of 1425.9 mAh g{sup −1}. The lithium storage mechanism in CoCO{sub 3} is studied by ex situ X-ray diffraction technique, ex situ infrared method, ex situ X-ray photoelectron spectroscopy and in situ X-ray diffraction technique. It is found that the electrochemical reactions between CoCO{sub 3} and Li firstly result in the formation of metal Co and Li{sub 2}CO{sub 3}, and then partial Li{sub 2}CO{sub 3} is further reduced into carbon (C{sup 0}), low-valence carbon (C{sup 2+}), and Li{sub 2}O. It also demonstrates that the electrochemical reaction between CoCO{sub 3} and Li is a partially reversible process. Based on these electrochemical results, it is obvious that narrow potential range can acquire a better reversibility for CoCO{sub 3}/Li batteries by suppressing particle pulverization. Besides, the comparison of CoCO{sub 3}, ball-milled CoCO{sub 3} and ball-milled CoCO{sub 3}/C composite also indicates that smaller active particle and carbon buffer are beneficial to obtain better cycling performance and higher reversible capacity.

  19. Pulsed laser deposited Si on multilayer graphene as anode material for lithium ion batteries

    Directory of Open Access Journals (Sweden)

    Gouri Radhakrishnan

    2013-12-01

    Full Text Available Pulsed laser deposition and chemical vapor deposition were used to deposit very thin silicon on multilayer graphene (MLG on a nickel foam substrate for application as an anode material for lithium ion batteries. The as-grown material was directly fabricated into an anode without a binder, and tested in a half-cell configuration. Even under stressful voltage limits that accelerate degradation, the Si-MLG films displayed higher stability than Si-only electrodes. Post-cycling images of the anodes reveal the differences between the two material systems and emphasize the role of the graphene layers in improving adhesion and electrochemical stability of the Si.

  20. Cyclic performance of silicon as anode material in lithium ion batteries

    OpenAIRE

    Kim, Seongseop; Cho, Maenghyo; Zhou, Min

    2014-01-01

    Silicon is a promising anode material owing to its high energy density which is an important aspect of the -performance metric for lithium ion batteries. In this study, the cyclic behavior of silicon as the anode material in lithium ion batteries is investigated. Chemical–mechanical coupling is considered to analyze the interactions between diffusion and factors influencing the mechanical response of materials. Galvanostatic–potentiostatic -charging/discharging cycles are used to investigate ...

  1. Porous Silicon as Anode Material for Li-ion Batteries : Structure and Performance

    OpenAIRE

    Ulvestad, Asbjørn

    2013-01-01

    Silicon has proven to have a great potential as anode material in lithium-ion batteries due to its high theoretical electrochemical capacity. However, silicon anodes deteriorate quickly during cyclic charging and discharging, rendering them useless in only a few cycles. This has been attributed to the stresses induced by the large volume change of the material during cycling. By using finely structured silicon, these stresses can be effectively reduced, in what is aptly called dimensional sta...

  2. Facile synthesis of reduced graphene oxide-porous silicon composite as superior anode material for lithium-ion battery anodes

    Science.gov (United States)

    Jiao, Lian-Sheng; Liu, Jin-Yu; Li, Hong-Yan; Wu, Tong-Shun; Li, Fenghua; Wang, Hao-Yu; Niu, Li

    2016-05-01

    We report a new method for synthesizing reduced graphene oxide (rGO)-porous silicon composite for lithium-ion battery anodes. Rice husks were used as a as a raw material source for the synthesis of porous Si through magnesiothermic reduction process. The as-obtained composite exhibits good rate and cycling performance taking advantage of the porous structure of silicon inheriting from rice husks and the outstanding characteristic of graphene. A considerably high delithiation capacity of 907 mA h g-1 can be retained even at a rate of 16 A g-1. A discharge capacity of 830 mA h g-1 at a current density of 1 A g-1 was delivered after 200 cycles. This may contribute to the further advancement of Si-based composite anode design.

  3. Magnesium Sulphide as Anode Material for Lithium-Ion Batteries

    International Nuclear Information System (INIS)

    Highlights: • A single step preparation method of magnesium sulphide-carbon composite by mechanically milling the elemental mixture is reported. • The as-prepared MgS-carbon composite was investigated as an anode for lithium-ion batteries. • From XRD and electrochemical studies a reversible lithiation/delithiation mechanism of MgS is concluded. • The practicality of MgS-carbon composite anode in full cell using lithium nickel manganese cobalt oxide (LNMC) and lithium iron phosphate (LFP) as cathodes are evaluated. -- Abstract: Herein, we report magnesium sulphide (MgS) as an anode for lithium ion batteries. Magnesium sulphide-carbon composite is directly synthesized by mechanically milling the elemental mixture. A possible lithiation and delithiation mechanism for MgS is proposed based on electrochemical and ex-situ XRD studies. The electrochemical reaction of MgS with lithium results in the formation of Li2S and Mg, the as-formed Mg simultaneously reacts with lithium and forms LixMg alloy further contributing to the capacity. A stable reversible capacity of 530 mAh g−1 was achieved after 100 cycles within the voltage window of 0.001–2.5 V. The compatibility of MgS anode was tested in full cell using lithium nickel manganese cobalt oxide (LNMC) and lithium iron phosphate (LFP) as cathodes

  4. 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...

  5. Investigation of Anode Materials for Lithium Ion Batteries

    OpenAIRE

    Zhong, Lanlan

    2016-01-01

    Lithium ion batteries, Lithium ion batteries (LIBs) have for several years dominated the market for cell phones, laptops, and several other portable electronic devices. In order to match the necessity of increasing need for higher energy density storage devices, for example, hybrid/electric vehicles. Higher energy density lithium ion batteries have to be investigated. Anode as one of the most important components of in LIBs has been intensively studied in recent years. Silicon, tin and metal...

  6. Well-constructed silicon-based materials as high-performance lithium-ion battery anodes

    Science.gov (United States)

    Liu, Lehao; Lyu, Jing; Li, Tiehu; Zhao, Tingkai

    2015-12-01

    Silicon has been considered as one of the most promising anode material alternates for next-generation lithium-ion batteries, because of its high theoretical capacity, environmental friendliness, high safety, low cost, etc. Nevertheless, silicon-based anode materials (especially bulk silicon) suffer from severe capacity fading resulting from their low intrinsic electrical conductivity and great volume variation during lithiation/delithiation processes. To address this challenge, a few special constructions from nanostructures to anchored, flexible, sandwich, core-shell, porous and even integrated structures, have been well designed and fabricated to effectively improve the cycling performance of silicon-based anodes. In view of the fast development of silicon-based anode materials, we summarize their recent progress in structural design principles, preparation methods, morphological characteristics and electrochemical performance by highlighting the material structure. We also point out the associated problems and challenges faced by these anodes and introduce some feasible strategies to further boost their electrochemical performance. Furthermore, we give a few suggestions relating to the developing trends to better mature their practical applications in next-generation lithium-ion batteries.

  7. Well-constructed silicon-based materials as high-performance lithium-ion battery anodes.

    Science.gov (United States)

    Liu, Lehao; Lyu, Jing; Li, Tiehu; Zhao, Tingkai

    2016-01-14

    Silicon has been considered as one of the most promising anode material alternates for next-generation lithium-ion batteries, because of its high theoretical capacity, environmental friendliness, high safety, low cost, etc. Nevertheless, silicon-based anode materials (especially bulk silicon) suffer from severe capacity fading resulting from their low intrinsic electrical conductivity and great volume variation during lithiation/delithiation processes. To address this challenge, a few special constructions from nanostructures to anchored, flexible, sandwich, core-shell, porous and even integrated structures, have been well designed and fabricated to effectively improve the cycling performance of silicon-based anodes. In view of the fast development of silicon-based anode materials, we summarize their recent progress in structural design principles, preparation methods, morphological characteristics and electrochemical performance by highlighting the material structure. We also point out the associated problems and challenges faced by these anodes and introduce some feasible strategies to further boost their electrochemical performance. Furthermore, we give a few suggestions relating to the developing trends to better mature their practical applications in next-generation lithium-ion batteries. PMID:26666682

  8. Nanotemplated platinum fuel cell catalysts and copper-tin lithium battery anode materials for microenergy devices

    Energy Technology Data Exchange (ETDEWEB)

    Rohan, J.F., E-mail: james.rohan@tyndall.ie [Tyndall National Institute, University College Cork, Lee Maltings, Cork (Ireland); Hasan, M.; Holubowitch, N. [Tyndall National Institute, University College Cork, Lee Maltings, Cork (Ireland)

    2011-11-01

    Highlights: > Anodic Aluminum oxide formation on Si substrate. > High density nanotemplated Pt catalyst on Si for integrated energy and electronics. > CuSn alloy deposition from a single, high efficiency methanesulfonate plating bath. > Nanotemplated CuSn Li anode electrodes with high capacity retention. - Abstract: Nanotemplated materials have significant potential for applications in energy conversion and storage devices due to their unique physical properties. Nanostructured materials provide additional electrode surface area beneficial for energy conversion or storage applications with short path lengths for electronic and ionic transport and thus the possibility of higher reaction rates. We report on the use of controlled growth of metal and alloy electrodeposited templated nanostructures for energy applications. Anodic aluminium oxide templates fabricated on Si for energy materials integration with electronic devices and their use for fuel cell and battery materials deposition is discussed. Nanostructured Pt anode catalysts for methanol fuel cells are shown. Templated CuSn alloy anodes that possess high capacity retention with cycling for lithium microbattery integration are also presented.

  9. Dissolution of Plutonium Scrub Alloy and Anode Heel Materials in H-Canyon

    International Nuclear Information System (INIS)

    H-Canyon has a ''gap'' in dissolver operations during the last three months of FY03. One group of material to be processed during the gap is pre-existing scrub alloy material. There are 14 cans of material containing approximately 3.8 kilograms of plutonium. Of the 14 cans, it was anticipated that four cans contain salts, two cans contain anode heel materials, and eight cans contain scrub alloy buttons. H-Canyon desires to process the materials using a flowsheet similar to the SS and C (sand, slag and crucible) dissolution flowsheet used in F-Canyon. The materials will be loaded into carbon steel cans and then placed into aluminum metal charging bundles. Samples were sent to Savannah River Technology Center (SRTC) for characterization and flowsheet testing -- four MSE salts, two anode heels, and seven scrub alloy buttons. SRTC dissolved and characterized each of the samples. Two of them, originally thought to be MSE salts, were found to be graphite mold materials and were unsuitable for processing in H-Canyon. Characterization studies confirmed that the identification of the remaining items as MSE salts, scrub alloy buttons, and anode heel materials was correct. The MSE salts and anode heels solids are comprised primarily of plutonium, potassium, sodium and chloride. Both the MSE salts and anode heels left behind small amounts of residual solids. The scrub alloy buttons are comprised primarily of plutonium and aluminum. The solids dissolve readily with light, effervescent gas generation at the material surface and only trace amounts of NOx generation. Of the seven button samples, four dissolved completely. Two button samples contained small amounts of tantalum that did not dissolve. The last of the seven scrub alloy samples left a trace amount of residual plutonium solids. It is anticipated that the presence of undissolved fissile material is a function of where the sample was located relative to the button surface

  10. Hybrid Direct Carbon Fuel Cell Performance with Anode Current Collector Material

    DEFF Research Database (Denmark)

    Deleebeeck, Lisa; Kammer Hansen, Kent

    2015-01-01

    The influence of the current collector on the performance of a hybrid direct carbon fuel cell (HDCFC), consisting of solid oxide fuel cell (SOFC) with a molten carbonate-carbon slurry in contact with the anode, has been investigated using current-voltage curves. Four different anode current...... collectors were studied: Au, Ni, Ag, and Pt. It was shown that the performance of the direct carbon fuel cell (DCFC) is dependent on the current collector materials, Ni and Pt giving the best performance, due to their catalytic activity. Gold is suggested to be the best material as an inert current collector...

  11. Carbon Cryogel and Carbon Paper-Based Silicon Composite Anode Materials for Lithium-Ion Batteries

    Science.gov (United States)

    Woodworth, James; Baldwin, Richard; Bennett, William

    2010-01-01

    A variety of materials are under investigation for use as anode materials in lithium-ion batteries, of which, the most promising are those containing silicon. 6 One such material is a composite formed via the dispersion of silicon in a resorcinol-formaldehyde (RF) gel followed by pyrolysis. Two silicon-carbon composite materials, carbon microspheres and nanofoams produced from nano-phase silicon impregnated RF gel precursors have been synthesized and investigated. Carbon microspheres are produced by forming the silicon-containing RF gel into microspheres whereas carbon nano-foams are produced by impregnating carbon fiber paper with the silicon containing RF gel to create a free standing electrode. 1-5 Both materials have demonstrated their ability to function as anodes and utilize the silicon present in the material. Stable reversible capacities above 400 mAh/g for the bulk material and above 1000 mAh/g of Si have been observed.

  12. Silicon Composite Anode Materials for Lithium Ion Batteries Based on Carbon Cryogels and Carbon Paper

    Science.gov (United States)

    Woodworth, James; Baldwin, Richard; Bennett, William

    2010-01-01

    A variety of materials are under investigation for use as anode materials in lithium-ion batteries, of which, the most promising are those containing silicon. One such material is a composite formed via the dispersion of silicon in a resorcinol-formaldehyde (RF) gel followed by pyrolysis. Two silicon-carbon composite materials, carbon microspheres and nanofoams produced from nano-phase silicon impregnated RF gel precursors have been synthesized and investigated. Carbon microspheres are produced by forming the silicon-containing RF gel into microspheres whereas carbon nanofoams are produced by impregnating carbon fiber paper with the silicon containing RF gel to create a free standing electrode. Both materials have demonstrated their ability to function as anodes and utilize the silicon present in the material. Stable reversible capacities above 400 mAh/g for the bulk material and above 1000 mAh/g of Si have been observed.

  13. Lithium alloys and metal oxides as high-capacity anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: •Progress in lithium alloys and metal oxides as anode materials for lithium-ion batteries is reviewed. •Electrochemical characteristics and lithium storage mechanisms of lithium alloys and metal oxides are summarized. •Strategies for improving electrochemical lithium storage properties of lithium alloys and metal oxides are discussed. •Challenges in developing lithium alloys and metal oxides as commercial anodes for lithium-ion batteries are pointed out. -- Abstract: Lithium alloys and metal oxides have been widely recognized as the next-generation anode materials for lithium-ion batteries with high energy density and high power density. A variety of lithium alloys and metal oxides have been explored as alternatives to the commercial carbonaceous anodes. The electrochemical characteristics of silicon, tin, tin oxide, iron oxides, cobalt oxides, copper oxides, and so on are systematically summarized. In this review, it is not the scope to retrace the overall studies, but rather to highlight the electrochemical performances, the lithium storage mechanism and the strategies in improving the electrochemical properties of lithium alloys and metal oxides. The challenges and new directions in developing lithium alloys and metal oxides as commercial anodes for the next-generation lithium-ion batteries are also discussed

  14. Study of Silicon Oxycarbide(SiOC) as Anode Materials for Li-ion Batteries

    OpenAIRE

    Vallachira Warriam Sasikumar Pradeep, Pradeep

    2013-01-01

    The principal object of this thesis is the investigation of silicon oxycarbide (SiOC) ceramics as anode material for Li-ion batteries. The investigated materials are prepared by cross linking commercial polymer siloxanes via hydrosylilation reactions or hybrid alkoxide precursors via sol-gel. The cross linked polymer networks are then converted in to ceramic materials by a pyrolysis process in controlled argon atmosphere at 800-1300 °C. In details the influence of carbon content on lithium...

  15. A novel mesoporous carbon-silica-titania nanocomposite as a high performance anode material in lithium ion batteries.

    Science.gov (United States)

    Zhou, Yuanyuan; Kim, Younghun; Jo, Changshin; Lee, Jinwoo; Lee, Chul Wee; Yoon, Songhun

    2011-05-01

    An ordered mesoporous carbon-silica-titania material was prepared using the tetra-constituents co-assembly method. As regards its anode performance in lithium ion batteries, the composite material anode exhibited a high capacity (875 mAh g(-1)), a higher initial efficiency (56%) and an improved rate. PMID:21424009

  16. Submicron organic nanofiber devices with different anode-cathode materials: A simple approach

    DEFF Research Database (Denmark)

    Henrichsen, Henrik Hartmann; Sturm, Heinz; Bøggild, Peter;

    2010-01-01

    The authors present a simple general method for simultaneously producing tens of submicron electrode gaps with different cathode and anode materials on top of nanofibers, nanowires, and nanotubes, with an optional gap size variation. Using this method, an ensemble of para-hexaphenylene (p6P) nano...

  17. Tantalum carbide as a novel support material for anode electrocatalysts in polymer electrolyte membrane water electrolysers

    OpenAIRE

    Polonský, Jakub; Petrushina, Irina; Christensen, Erik; Bouzek, K.; Prag, Carsten Brorson; Andersen, Jens Enevold Thaulov; Bjerrum, Niels

    2012-01-01

    Iridium oxide (IrO2) currently represents a state of the art electrocatalyst for anodic oxygen evolution. Since iridium is both expensive and scarce, the future practical application of this process makes it essential to reduce IrO2 loading on the anodes of PEM water electrolysers. In the present study an approach to utilising a suitable electrocatalyst support was followed. Of the materials selected from a literature review, TaC has proved to be stable under the conditions of the accelerated...

  18. SiCN based Anode Materials for Lithium-Ion Batteries

    OpenAIRE

    Reinold, Lukas Mirko

    2016-01-01

    This thesis deals with the investigation of polymer-derived silicon carbonitride based anode materials for their application in lithium-ion batteries. Carbon-rich silicon carbonitrides are obtained by a pyrolysis of different organosilicon precursors, namely poly(phenylvinylsilylcarbodiimide), poly(phenylvinylsilazane), poly(diphenylsilylcarbodiimide), poly(phenylsilsesquicarbodiimide) and poly(phenylsilsesquiazane). The materials are characterized by means of Raman spectroscopy, elemental an...

  19. Review on recent progress of nanostructured anode materials for Li-ion batteries

    KAUST Repository

    Goriparti, Subrahmanyam

    2014-07-01

    This review highlights the recent research advances in active nanostructured anode materials for the next generation of Li-ion batteries (LIBs). In fact, in order to address both energy and power demands of secondary LIBs for future energy storage applications, it is required the development of innovative kinds of electrodes. Nanostructured materials based on carbon, metal/semiconductor, metal oxides and metal phosphides/nitrides/sulfides show a variety of admirable properties for LIBs applications such as high surface area, low diffusion distance, high electrical and ionic conductivity. Therefore, nanosized active materials are extremely promising for bridging the gap towards the realization of the next generation of LIBs with high reversible capacities, increased power capability, long cycling stability and free from safety concerns. In this review, anode materials are classified, depending on their electrochemical reaction with lithium, into three groups: intercalation/de-intercalation, alloy/de-alloy and conversion materials. Furthermore, the effect of nanoscale size and morphology on the electrochemical performance is presented. Synthesis of the nanostructures, lithium battery performance and electrode reaction mechanisms are also discussed. To conclude, the main aim of this review is to provide an organic outline of the wide range of recent research progresses and perspectives on nanosized active anode materials for future LIBs.

  20. Anodized titania: Processing and characterization to improve cell-materials interactions for load bearing implants

    Science.gov (United States)

    Das, Kakoli

    The objective of this study is to investigate in vitro cell-materials interactions using human osteoblast cells on anodized titanium. Titanium is a bioinert material and, therefore, gets encapsulated after implantation into the living body by a fibrous tissue that isolates them from the surrounding tissues. In this work, bioactive nonporous and nanoporous TiO2 layers were grown on commercially pure titanium substrate by anodization process using different electrolyte solutions namely (1) H3PO 4, (2) HF and (3) H2SO4, (4) aqueous solution of citric acid, sodium fluoride and sulfuric acid. The first three electrolytes produced bioactive TiO2 films with a nonporous structure showing three distinctive surface morphologies. Nanoporous morphology was obtained on Ti-surfaces from the fourth electrolyte at 20V for 4h. Cross-sectional view of the nanoporous surface reveals titania nanotubes of length 600 nm. It was found that increasing anodization time initially increased the height of the nanotubes while maintaining the tubular array structure, but beyond 4h, growth of nanotubes decreased with a collapsed array structure. Human osteoblast (HOB) cell attachment and growth behavior were studied using an osteoprecursor cell line (OPC 1) for 3, 7 and 11 days. Colonization of the cells was noticed with distinctive cell-to-cell attachment on HF anodized surfaces. TiO2 layer grown in H2SO4 electrolyte did not show significant cell growth on the surface, and some cell death was also noticed. Good cellular adherence with extracellular matrix extensions in between the cells was noticed for samples anodized with H3PO 4 electrolyte and nanotube surface. Cell proliferation was excellent on anodized nanotube surfaces. An abundant amount of extracellular matrix (ECM) between the neighboring cells was also noticed on nanotube surfaces with filopodia extensions coming out from cells to grasp the nanoporous surface for anchorage. To better understand and compare cell-materials interactions

  1. Porous silicon based anode material formed using metal reduction

    Energy Technology Data Exchange (ETDEWEB)

    Anguchamy, Yogesh Kumar; Masarapu, Charan; Deng, Haixia; Han, Yongbong; Venkatachalam, Subramanian; Kumar, Sujeet; Lopez, Herman A.

    2015-09-22

    A porous silicon based material comprising porous crystalline elemental silicon formed by reducing silicon dioxide with a reducing metal in a heating process followed by acid etching is used to construct negative electrode used in lithium ion batteries. Gradual temperature heating ramp(s) with optional temperature steps can be used to perform the heating process. The porous silicon formed has a high surface area from about 10 m.sup.2/g to about 200 m.sup.2/g and is substantially free of carbon. The negative electrode formed can have a discharge specific capacity of at least 1800 mAh/g at rate of C/3 discharged from 1.5V to 0.005V against lithium with in some embodiments loading levels ranging from about 1.4 mg/cm.sup.2 to about 3.5 mg/cm.sup.2. In some embodiments, the porous silicon can be coated with a carbon coating or blended with carbon nanofibers or other conductive carbon material.

  2. Manganese pyridinedicarboxylates: New anode materials for lithium-ion batteries with good cycling performance

    International Nuclear Information System (INIS)

    Highlights: • Manganese 2,3-pyridinedicarboxylate and 2,5-pyridinedicarboxylate. • Firstly tested as anode materials. • High capacity and good cycle stability. - Abstract: It is significant to discover new environmental friendly, sustainable and renewable electrode materials for lithium-ion batteries. Manganese dicarboxylate [Mn2(pdc)2(H2O)3]n⋅2nH2O (pdc = pyridine-2,3-dicarboxylate) is firstly found to be a high-energy anode material for lithium-ion batteries. It shows a high discharge capacity of 573.7 mA h g−1 for the second cycle between a 0.05 and 3.0 V voltage limit at a discharge current density of 500 mA g−1. The reversible capacity of 457.2 mA h g−1 is remained after 100 cycles with a capacity retention being 79.6%. In addition, it is found that Mn 2,5-pyridinedicarboxyle was also stable anode materials with high capacity

  3. Phase wettability and microstructural evolution in solid oxide fuel cell anode materials

    International Nuclear Information System (INIS)

    Recent experimental and theoretical findings suggest that high-temperature solid oxide fuel cells (SOFCs) often suffer from performance degradation due to coarsening of the metallic-phase particles within the anode. In this study, we explore the feasibility of improving the microstructural stability of SOFC anode materials by tuning the contact angle between the metallic phase and electrolyte particles. To this end, a continuum diffuse-interface model is employed to capture the coarsening behavior of the metallic phase and simulate a range of equilibrium contact angles. The evolution of performance-critical, microstructural features is presented for varying degrees of phase wettability. It is found that both the density of electrochemically active triple- phase regions and contiguity of the electron-conducting phase display undesirable minima near the contact angle of conventional SOFC materials. Our results suggest that tailoring the interfacial properties of the constituent phases could lead to a significant increase in the performance and lifetime of SOFCs

  4. Facile synthesis of one-dimensional zinc vanadate nanofibers for high lithium storage anode material

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Lei [Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122 (China); International Joint Research Laboratory for Advanced Functional Textile Materials, Jiangnan University, Wuxi 214122 (China); Fei, Yaqian; Chen, Ke; Li, Dawei; Wang, Xin [Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122 (China); Wang, Qingqing [Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122 (China); International Joint Research Laboratory for Advanced Functional Textile Materials, Jiangnan University, Wuxi 214122 (China); Wei, Qufu, E-mail: qfwei@jiangnan.edu.cn [Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122 (China); International Joint Research Laboratory for Advanced Functional Textile Materials, Jiangnan University, Wuxi 214122 (China); Qiao, Hui [Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122 (China)

    2015-11-15

    One-dimensional (1D) zinc vanadate (α-Zn{sub 2}V{sub 2}O{sub 7}) nanofibers have been synthesized through electrospinning combined with an annealing process. When used as anode material for lithium-ion batteries (LIBs), electrospun 1D α-Zn{sub 2}V{sub 2}O{sub 7} nanofibers exhibit a reversible capacity of ∼708 mAh g{sup −1} after 100 cycles at a current density of 50 mA g{sup −1}. A good rate capability is also achieved even at higher current densities. When cycled at a current density of 2000 mA g{sup −1}, the electrode can still show a reversible capacity of ∼311 mAh g{sup −1}. The excellent cycle performance and rate capability may be due to the 1D nanofiber architectures, mesoporous structures, and relatively large specific surface area, which can provide a short ion diffusion path and continuous electron transportation. Therefore, this work presents a simple and efficient approach for fabrication of 1D α-Zn{sub 2}V{sub 2}O{sub 7} nanofibers, which are promising high-performance anode materials for LIBs. - Highlights: • Electrospun 1D α-Zn{sub 2}V{sub 2}O{sub 7} nanofibers are first synthesized for anode material. • The electrochemical reaction mechanism of this material is discussed. • A reversible capacity of ∼708 mAh g{sup −1} is obtained after 100 cycles at 50 mA g{sup −1}. • 1D α-Zn{sub 2}V{sub 2}O{sub 7} nanofiber anodes show excellent rate capability for LIBs.

  5. Facile synthesis of one-dimensional zinc vanadate nanofibers for high lithium storage anode material

    International Nuclear Information System (INIS)

    One-dimensional (1D) zinc vanadate (α-Zn2V2O7) nanofibers have been synthesized through electrospinning combined with an annealing process. When used as anode material for lithium-ion batteries (LIBs), electrospun 1D α-Zn2V2O7 nanofibers exhibit a reversible capacity of ∼708 mAh g−1 after 100 cycles at a current density of 50 mA g−1. A good rate capability is also achieved even at higher current densities. When cycled at a current density of 2000 mA g−1, the electrode can still show a reversible capacity of ∼311 mAh g−1. The excellent cycle performance and rate capability may be due to the 1D nanofiber architectures, mesoporous structures, and relatively large specific surface area, which can provide a short ion diffusion path and continuous electron transportation. Therefore, this work presents a simple and efficient approach for fabrication of 1D α-Zn2V2O7 nanofibers, which are promising high-performance anode materials for LIBs. - Highlights: • Electrospun 1D α-Zn2V2O7 nanofibers are first synthesized for anode material. • The electrochemical reaction mechanism of this material is discussed. • A reversible capacity of ∼708 mAh g−1 is obtained after 100 cycles at 50 mA g−1. • 1D α-Zn2V2O7 nanofiber anodes show excellent rate capability for LIBs

  6. Enhancement of Electrochemical Stability about Silicon/Carbon Composite Anode Materials for Lithium Ion Batteries

    OpenAIRE

    Wei Xiao; Chang Miao; Xuemin Yan; Qing Sun; Ping Mei

    2015-01-01

    Silicon/carbon (Si/C) composite anode materials are successfully synthesized by mechanical ball milling followed by pyrolysis method. The structure and morphology of the composite are characterized by X-ray diffraction and scanning electron microscopy and transmission electron microscope, respectively. The results show that the composite is composed of Si, flake graphite, and phenolic resin-pyrolyzed carbon, and Si and flake graphite are enwrapped by phenolic resin-pyrolyzed carbon, which can...

  7. A Chemo-Mechanical model of delithiation in high-capacity anode materials

    OpenAIRE

    Yang, Hui; Zhang, Sulin

    2014-01-01

    We present a chemo-mechanical model to investigate the delithiation-induced phase transformation, morphological evolution, stress generation, void nucleation, and growth in high-capacity anode materials such as silicon (Si) and germanium (Ge). The model couples lithium (Li) diffusion with large elasto-plastic deformation by solving a set of coupled phase field and mechanical equilibrium equations using the finite element method, which leads to the coevolution of the Li concentration, stress d...

  8. Enhancement of Electrochemical Stability about Silicon/Carbon Composite Anode Materials for Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Wei Xiao

    2015-01-01

    Full Text Available Silicon/carbon (Si/C composite anode materials are successfully synthesized by mechanical ball milling followed by pyrolysis method. The structure and morphology of the composite are characterized by X-ray diffraction and scanning electron microscopy and transmission electron microscope, respectively. The results show that the composite is composed of Si, flake graphite, and phenolic resin-pyrolyzed carbon, and Si and flake graphite are enwrapped by phenolic resin-pyrolyzed carbon, which can provide not only a good buffering matrix but also a conductive network. The Si/C composite also shows good electrochemical stability, in which the composite anode material exhibits a high initial charge capacity of 805.3 mAh g−1 at 100 mA g−1 and it can still deliver a high charge capacity of 791.7 mAh g−1 when the current density increases to 500 mA g−1. The results indicate that it could be used as a promising anode material for lithium ion batteries.

  9. Bismuth Nanoparticles Embedded in Carbon Spheres as Anode Materials for Sodium/Lithium-Ion Batteries.

    Science.gov (United States)

    Yang, Fuhua; Yu, Fan; Zhang, Zhian; Zhang, Kai; Lai, Yanqing; Li, Jie

    2016-02-12

    Sodium-ion batteries (SIBs) are regarded as an attractive alternative to lithium-ion batteries (LIBs) for large-scale commercial applications, because of the abundant terrestrial reserves of sodium. Exporting suitable anode materials is the key to the development of SIBs and LIBs. In this contribution, we report on the fabrication of Bi@C microspheres using aerosol spray pyrolysis technique. When used as SIBs anode materials, the Bi@C microsphere delivered a high capacity of 123.5 mAh g(-1) after 100 cycles at 100 mA g(-1) . The rate performance is also impressive (specific capacities of 299, 252, 192, 141, and 90 mAh g(-1) are obtained under current densities of 0.1, 0.2, 0.5, 1, and 2 A g(-1) , respectively). Furthermore, the Bi@C microsphere also proved to be suitable LIB anode materials. The excellent electrochemical performance for both SIBs and LIBs can attributed to the Bi@C microsphere structure with Bi nanoparticles uniformly dispersed in carbon spheres. PMID:26757402

  10. Monolithic Graphene Trees as Anode Material for Lithium Ion Batteries with High C-Rates.

    Science.gov (United States)

    Jeong, Seung Yol; Yang, Sunhye; Jeong, Sooyeon; Kim, Ick Jun; Jeong, Hee Jin; Han, Joong Tark; Baeg, Kang-Jun; Lee, Geon-Woong

    2015-06-01

    Monolithically structured reduced graphene oxide (rGO), prepared from a highly concentrated and conductive rGO paste, is introduced as an anode material for lithium ion batteries with high rate capacities. This is achieved by a mixture of rGO paste and the water-soluble polymer sodium carboxymethylcellulose (SCMC) with freeze drying. Unlike previous 3D graphene porous structures, the monolithic graphene resembles densely branched pine trees and has high mechanical stability with strong adhesion to the metal electrodes. The structures contain numerous large surface area open pores that facilitate lithium ion diffusion, while the strong hydrogen bonding between the graphene layers and SCMC provides high conductivity and reduces the volume changes that occur during cycling. Ultrafast charge/discharge rates are obtained with outstanding cycling stability and the capacities are higher than those reported for other anode materials. The fabrication process is simple and straightforward to adjust and is therefore suitable for mass production of anode electrodes for commercial applications. PMID:25656352

  11. Carbon matrix/SiNWs heterogeneous block as improved reversible anodes material for lithium ion batteries

    Institute of Scientific and Technical Information of China (English)

    Yao; Wang; Long; Ren; Yundan; Liu; Xuejun; Liu; Kai; Huang; Xiaolin; Wei; Jun; Li; Xiang; Qi; Jianxin; Zhong

    2014-01-01

    A novel carbon matrix/silicon nanowires(SiNWs) heterogeneous block was successfully produced by dispersing SiNWs into templated carbon matrix via a modified evaporation induced self-assembly method. The heterogeneous block was determined by X-ray diffraction, Raman spectra and scanning electron microscopy. As an anode material for lithium batteries, the block was investigated by cyclic voltammograms(CV), charge/discharge tests, galvanostatic cycling performance and A. C. impedance spectroscopy. We show that the SiNWs disperse into the framework, and are nicely wrapped by the carbon matrix. The heterogeneous block exhibits superior electrochemical reversibility with a high specific capacity of 529.3 mAh/g in comparison with bare SiNWs anode with merely about 52.6 mAh/g capacity retention. The block presents excellent cycle stability and capacity retention which can be attributed to the improvement of conductivity by the existence of carbon matrix and the enhancement of ability to relieve the large volume expansion of SiNWs during the lithium insertion/extraction cycle. The results indicate that the as-prepared carbon matrix/SiNWs heterogeneous block can be an attractive and potential anode material for lithium-ion battery applications.

  12. Electrolytic deposition of Sn-coated mesocarbon microbeads as anode material for lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Min-Jen [Department of Materials Engineering, National Chung Hsing University, Taichung 40227, Taiwan (China); Jen-Teh Junior College of Medicine, Nursing and Management, Taiwan (China); Tsai, Du-Cheng [Department of Materials Engineering, National Chung Hsing University, Taichung 40227, Taiwan (China); Ho, Wen-Hsien [Taiwan Textile Research Institute, Taipei 23674, Taiwan (China); Li, Ching-Fei, E-mail: chingfei.li@gmail.com [Phoenix Silicon International Corporation, Hsinchu 30094, Taiwan (China); Shieu, Fuh-Sheng, E-mail: fsshieu@dragon.nchu.edu.tw [Department of Materials Engineering, National Chung Hsing University, Taichung 40227, Taiwan (China); Center of Nanoscience and Nanotechnology, National Chung Hsing University, Taichung 40227, Taiwan (China)

    2013-11-15

    Deposited of crystalline tin (Sn) coatings on mesocarbon microbead (MCMB) powder as anodes of lithium ion (Li-ion) battery was conducted in the SnSO{sub 4} solution by a cathodic electrochemical synthesis. The Sn-coated MCMB specimens were characterized by X-ray diffraction, scanning electron microscopy, and charge/discharge tests. The synthesis condition of Sn-coated MCMB was optimized by considering the agglomeration, size, and adhesion of the samples to the current collectors in the battery. The Sn-coated MCMB electrodes exhibit increased reversible capacity without sacrificing its cycling behavior, compared with bare MCMB electrodes. It is concluded that electrolysis-deposited Sn-coated MCMB electrodes may emerge as a practical and promising anode material for secondary Li-ion batteries.

  13. Electrolytic deposition of Sn-coated mesocarbon microbeads as anode material for lithium ion battery

    International Nuclear Information System (INIS)

    Deposited of crystalline tin (Sn) coatings on mesocarbon microbead (MCMB) powder as anodes of lithium ion (Li-ion) battery was conducted in the SnSO4 solution by a cathodic electrochemical synthesis. The Sn-coated MCMB specimens were characterized by X-ray diffraction, scanning electron microscopy, and charge/discharge tests. The synthesis condition of Sn-coated MCMB was optimized by considering the agglomeration, size, and adhesion of the samples to the current collectors in the battery. The Sn-coated MCMB electrodes exhibit increased reversible capacity without sacrificing its cycling behavior, compared with bare MCMB electrodes. It is concluded that electrolysis-deposited Sn-coated MCMB electrodes may emerge as a practical and promising anode material for secondary Li-ion batteries.

  14. Polymer microsphere embedded Si/graphite composite anode material for lithium rechargeable battery

    International Nuclear Information System (INIS)

    Si/graphite composite materials embedded with polymer microsphere as an elastic inactive phase were prepared by high-energy mechanical milling and investigated as a high capacity anode material for lithium rechargeable battery. Improved capacity retention was achieved with the composite. In situ measurement of the electrode thickness revealed that the swelling of the electrode became smaller with the increase of polymer microsphere content. It is believed that polymer microsphere played a buffering role of accommodating the mechanical strains induced by silicon expansion during lithiation, resulting in the suppression of the volume expansion of the electrode, which improved the cycle performance of the electrode.

  15. Electrospun carbon-cobalt composite nanofiber as an anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Carbon-cobalt (C/Co) composite nanofibers with diameters from 100 to 300 nm were prepared by electrospinning and subsequent heat treatment. They were characterized by X-ray diffraction, scanning electron microscopy, galvanostatic cell cycling and impedance spectroscopy. As a lithium storage material, these fibers exhibit excellent electrochemical properties with high reversible capacity (>750 mA h g-1) and good rate capability (578 mA h g-1 at 1 C rate). These composite fibers are a promising anode material for high-power Li-ion batteries

  16. Blue TiO2 Nanotube Array as an Oxidant Generating Novel Anode Material Fabricated by Simple Cathodic Polarization

    International Nuclear Information System (INIS)

    Graphical abstract: - Abstract: Great interest in anode materials has dramatically emerged with increasing demand for electrochemically generated oxidants in industrial electrochemistry. For the last five decades, these needs have been mostly achieved by the introduction of two well-known anode materials, the dimensional stable anode (DSA®) and boron-doped diamond (BDD) electrodes. Nevertheless, the high cost and complicated process in fabricating these electrodes remains as a big obstacle for further development. Here, we report a novel anode material for the production of oxidants, the dark blue colored TiO2 nanotube array (NTA) (denoted as Blue TiO2 NTA) which has never been successfully achieved with titania-based materials. This titania-based electrocatalyst with irreversible electrochromism and high conductivity was successfully fabricated with simple cathodic polarization of anatase TiO2 NTA and exhibits the excellent electrocatalytic activity in generating chlorine (Cl2) and hydroxyl radical (• OH) which is comparable to the commercial DSA® and BDD electrodes, respectively. Thus, this Blue TiO2 NTA is suggested as a potential cost effective anodic material in industrial electrochemistry. In addition, even in other metal oxides other than titania, the cathodic polarization (accompanied with irreversible electrochromism) method may be applied to explore a new route for low-cost and novel anodic materials

  17. Modified carbons with optimized electrochemical properties as anode material in lithium ion cells

    International Nuclear Information System (INIS)

    Lithium ion cells are widely used rechargeable batteries for applications in laptops or mobile phones. Purpose of this work is the optimization of the commonly used graphite intercalation anodes. During the first charge/discharge cycles electrolyte decomposition takes place at the anode followed by formation of a film, which hinders further decomposition of the electrolyte. This reaction can be controlled by the surface composition of the anodes. In this work the surface composition and structure of different graphites were changed by gas treatment. Referring to the 'dangling bonds' model, the activated graphite surface with free bonds and adsorption places was treated with a reactive gas. The applicability of the obtained modified graphites as electrode materials was tested in charge/discharge studies. The results were correlated with surface properties of the graphites. For this purpose the specific surface area of the differently treated graphites was determined by BET measurements. The chemical composition and the distribution of the surface groups was measured by electron scanning chemical analysis (ESCA). Optical pictures of the surfaces were obtained by scanning electron microscopy (SEM). (author)

  18. Periodic porous silicon thin films with interconnected channels as durable anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    A novel porous Si (PSi) films with interconnected channels and periodic nanostructures are fabricated by a facile electrochemical etching method. The films thus obtained feature highly porous structures with nano-branches connecting pores, possessing periodically varying porosity profiles along the film thickness direction. These periodic porous Si films are found to be promising anode materials for rechargeable lithium ion batteries with a high reversible specific capacity over 2500 mAh g−1 and capacity retention over 83% after 60 cycles, which compares favorably with the conventional Si-based electrodes, including the commercially available Si nanoparticles, sputtered Si thin films, and the normal porous Si films with homogenous porosities. The improved cycling stability achieved on the periodic porous Si film is ascribed to its special nanoporous morphology featuring high surface area, interconnecting nano-branches, and structural periodicity, which helps efficiently accommodate the volume expansion and contraction along both the vertical and the planner directions during lithiation and delithiation. - Highlights: • Free-standing porous Si films with interconnected channels have been fabricated. • These PSi films as anode deliver a high reversible specific capacity over 2500 mAh g−1. • The special porous structure plays an important role in stabilizing the anodes

  19. Interfacial electron transfer and bioelectrocatalysis of carbonized plant material as effective anode of microbial fuel cell

    International Nuclear Information System (INIS)

    ABSTRACT: Effective use of natural materials to fabricate porous carbonaceous structures for anodes of microbial fuel cells (MFCs) has a high potential for substantial cost reduction in MFC. In this study, three kinds of plant materials, i.e. king mushroom, wild mushroom and corn stem, were investigated for fabrication of conductive electrode materials by simple carbonization procedures. Structure–reactivity relationships of these electrodes were systematically studied with electrochemical redox probe ([Fe(CN)6]3−/4−) and biofilm electroactivity. The electrochemical and bioelectrochemical accessibilities of the carbonized electrodes were evaluated by impedance, cyclic voltammetry and chronoamperometry techniques in order to study the electron transfer rate (Kapp), charge transfer resistances, oxidative current density and bioelectroactive moieties. The results showed that the electron transfer resistance (Rct) was 94 Ω for carbonized corn stem electrode with an electron transfer rate (Kapp) of 3.44 × 10−2 cm s−1 for Fe2+/Fe3+ redox probe. Higher bioelectroactivity (9.29 × 10−8 mol cm−2) was found from biofilm on carbonized corn stem (Rbiofilm, 45 Ω) with an electron transfer rate (bacteria-anode) of 63 × 10−5 cm s−1. The maximum bioelectrocatalytic current (imax) of 3.12 mA cm−2 was obtained on carbon electrode derived from corn stem. That is 8 times higher than plain graphite electrode. The porous architecture, high electron transfer rate and high electroactive biofilm growth are attributes that qualify natural-material carbon anodes as low-cost alternative for MFC

  20. Development of high-energy silicon-based anode materials for lithium-ion storage

    Science.gov (United States)

    Yi, Ran

    The emerging markets of electric vehicles (EV) and hybrid electric vehicles (HEV) generate a tremendous demand for low-cost lithium-ion batteries (LIBs) with high energy and power densities, and long cycling life. The development of such LIBs requires development of low cost, high-energy-density cathode and anode materials. Conventional anode materials in commercial LIBs are primarily synthetic graphite-based materials with a capacity of ˜370 mAh/g. Improvements in anode performance, particularly in anode capacity, are essential to achieving high energy densities in LIBs for EV and HEV applications. This dissertation focuses on development of micro-sized silicon-carbon (Si-C) composites as anode materials for high energy and power densities LIBs. First, a new, low-cost, large-scale approach was developed to prepare a micro-sized Si-C composite with excellent performance as an anode material for LIBs. The composite shows a reversible capacity of 1459 mAh/g after 200 cycles at 1 A/g (97.8% capacity retention) and excellent high rate performance of 700 mAh/g at 12.8 A/g, and also has a high tap density of 0.78 g/cm3. The structure of the composite, micro-sized as a whole, features the interconnected nanoscale size of the Si building blocks and the uniform carbon filling, which enables the maximum utilization of silicon even when the micro-sized particles break into small pieces upon cycling. To understand the effects of key parameters in designing the micro-sized Si-C composites on their electrochemical performance and explore how to optimize them, the influence of Si nanoscale building block size and carbon coating on the electrochemical performance of the micro-sized Si-C composites were investigated. It has been found that the critical Si building block size is 15 nm, which enables a high capacity without compromising the cycling stability, and that carbon coating at higher temperature improves the 1st cycle coulombic efficiency (CE) and the rate capability

  1. Influence of Treatment Temperature on Microstructure and Properties of YSZ-NiO Anode Materials.

    Science.gov (United States)

    Podhurska, Viktoriya; Vasyliv, Bogdan; Ostash, Orest; Brodnikovskyi, Yegor; Vasylyev, Oleksandr

    2016-12-01

    The cyclic treatment technique (redox cycling) comprising stages of material exposition in reducing and oxidizing high-temperature environments and intermediate degassing between these stages has been developed to improve the structural integrity of YSZ-NiO ceramic anode substrates for solid oxide fuel cells. A series of specimens were singly reduced in a hydrogenous environment (the Ar-5 vol% Н2 mixture or hydrogen of 99.99 vol% H2 purity) under the pressure of 0.15 MPa or subjected to redox cycling at 600 or 800 °C. The influence of redox cycling at the treatment temperatures of 600 and 800 °C on the structure, strength and electrical conductivity of the material has been analysed. Using the treatment temperature 600 °C, a structure providing improved physical and mechanical properties of the material was formed. However, at the treatment temperature 800 °C, an anode structure with an array of microcracks was formed that significantly reduced the strength and electrical conductivity of the material. PMID:26880730

  2. A new anode material LiMoS2 for use in rechargeable Lithium Ion Batteries

    Institute of Scientific and Technical Information of China (English)

    YANG Shui-jin; AI Chang-chun; LIANG Yong-guang; SUN Ju-tang

    2004-01-01

    The novel applications of molybdenum disulfide in recent research were reviewed, such as in lubricant, catalyst and photoelectrochemical solar cells. Recently, we found that LiMoS2 is a good candidate for new anode materials for lithium ion batteries with high lithium storage capacity.Here, the anode material LiMoS2 was synthesized by a hydrothermal method at 150℃ and the electrochemical characterization as an anode material for lithium ion batteries was examined.put in Teflon-lined stainless steel autoclaves of capacity 40 mL. Distilled water was used to fill the autoclaves to 70 % of the total volume. The autoclaves were maintained at 150℃ for 24 h and then cooled naturally. The resulting dark-gray powders were filled and washed with distilled water,diluted hydrochloric acid and ethanol, successively. The final products were dried at 80℃ for 24 h.The powder X-ray diffraction pattern showed the prepared LiMoS2 was amorphous structure. A test cell using LiMoS2 as the active material was discharged and charged between 3 and 0.01 V with respect to Li metal at a constant current density of C/5 (that is, one lithium per formula unit in 5 hours). During the first discharge, the potential rapidly drops to reach a large plateau at 2.2 V, then slowly drops to the other plateau at 0.8 V, and then continuously decreases down to 0.01V. There is only a plateau at 1.35 V in the subsequent discharge curves. The plateaus of charge potential appear at about 1.9 V.The irreversible loss was 41% in the first cycle. The ratio of discharge and charge is more than 99%in the subsequent cycles. Moreover, the ratio of discharge and charge almost reaches 100% after thedemonstrated that LiMoS2 has a very high capacity and a good cycle-ability as an anode material forlithium ion batteries.

  3. New Insights in to the Lithium Storage Mechanism in Polymer Derived SiOC Anode Materials

    International Nuclear Information System (INIS)

    Highlights: • Polymer-derived SiOC ceramics are studied as anode in Li-ion batteries. • Li insertion capacity and cycling stability are correlated to the structure of SiOC. • First insertion capacity of SiCxO2(1-x) network goes up to 1300 mAhg−1. • The specific capacity of the C-poor SiOC degrades faster than the C-rich SiOC. - Abstract: Polymer derived silicon oxycarbide (SiOC) materials are prepared by the pyrolysis of preceramic polymers obtained from polyhydridomethylsiloxane using 1,3,5,7-tetramethyl1,3,5,7-tetravinyl cyclotetrasiloxane or divinyl benzene as a cross-linking agent. The pyrolysis is carried out in an inert atmosphere at 1000 and 1300 °C. The carbon content of SiOC is varied by changing the amount of starting precursors maintaining the same O/Si atomic ratio of about 1. Electrochemical measurements are performed in order to evaluate the materials in terms of their application as anodes in Li-ion batteries. Detailed structural characterization study is performed using complementary techniques with the aim of correlating the electrochemical behavior with the structure of the SiOC anodes. Results suggest that SiOC anodes behave as a composite material consisting of a disordered silicon oxycarbide phase having a very high first insertion capacity of ca 1300 mAh g−1 and a free C phase. However, the charge irreversible trapped into the amorphous silicon oxycarbide network is also high and therefore the maximum reversible lithium storage capacity of 650mAh g−1 is measured on high-C content SiOCs for which the balance between the two phases, namely the amorphous silicon oxycarbide and the free C phase, is optimal. The high carbon content SiOC show also an excellent cycling stability and performance at high charging/discharging rate: the reversible capacity at 2 C rate being around 200 mAh g−1. Increasing the pyrolysis temperature has an opposite effect on the low-C and high-C materials: for the latter one the reversible capacity

  4. Co3O4 nanowires as high capacity anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Highlights: ► The Co3O4 nanowires are synthesized from decomposition of CoC2O4·2H2O nanowires. ► The synthesis procedure shows us a facile and highly productive strategy. ► The Co3O4 nanowires are suitable as a promising anode material for LIBs. ► High capacity and good cycling stability are achieved for the Co3O4 nanowires. - Abstract: Co3O4 nanowires were synthesized from the decomposition of CoC2O4·2H2O nanowires which were obtained through a polyvinyl alcohol (PVA)-assisted solution-based precipitation process. And the formation mechanism of CoC2O4·2H2O nanowires was discussed. The Co3O4 nanowires had diameters in the range of 30–60 nm and lengths of several micrometers, inheriting the morphology of the CoC2O4·2H2O nanowires. The Co3O4 nanowires as an anode material in lithium-ion batteries exhibited a stable specific discharge/charge capacity of 611 mAh/g and 598 mAh/g after fifty cycles at a current density of 0.11 A/g, which were much higher than that of commercial Co3O4 nanoparticles. In addition, the charge capacity of the as-synthesized Co3O4 nanowires was more than two times higher than that of the commercial Co3O4 nanoparticles at a current density of 1.1 A/g. These results indicate that the as-prepared Co3O4 nanowires have potential to be a promising candidate as high capacity anode material in the next generation lithium-ion batteries.

  5. An Sn-Fe/carbon nanocomposite as an alternative anode material for rechargeable lithium batteries

    International Nuclear Information System (INIS)

    Sn-Fe/carbon nanocomposites were synthesized by the mechanochemical treatment of Sn with various amounts of an Fe/C composite through the pyrolysis of Fe(III) acetylacetonate. The composites were then evaluated as alternative anode materials for rechargeable lithium batteries. Based on the obtained ex situ X-ray diffraction (XRD) data, X-ray absorption spectroscopy (XAS) results, and differential capacity plots (DCPs), a reaction mechanism was suggested. It was found that increasing the amounts of the SnFe phase and pyrolyzed carbon in the composite improved its electrochemical characteristics in terms of its capacity retention

  6. Carbon-coated mesoporous SnO2 nanospheres as anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    In this paper mesoporous SnO2 nanospheres with an average diameter of about 83 nm, composed of many tiny primary particles (∼10 nm) and holes, are synthesized on a large scale by a simple hydrothermal route. The as-prepared mesoporous SnO2 nanospheres were uniformly coated with carbon by a further hydrothermal treatment in glucose aqueous solution. As anode materials for lithium-ion batteries, the core–shell SnO2/C nanocomposites exhibit a markedly improved cycling performance.

  7. Orthorhombic Lithium Titanium Phosphate as an Anode Material for Li-ion Rechargeable Battery

    International Nuclear Information System (INIS)

    Highlights: • Li-rich orthorhombic lithium titanium phosphate (OLTP) has been synthesized via a sol-gel route. • OLTP adopts a different space group from the previously reported rhombohedral lithium titanium phosphate (RLTP) and shows solid-solution charge/discharge curves. • OLTP shows higher Li+ diffusivity and electrical conductivity, which makes it an attractive alternative for RLTP. - Abstract: Rhombohedral lithium titanium phosphate, LiTi2(PO4)3, has been considered a suitable anode material for aqueous lithium-ion batteries. However, the electrochemical behaviors of pure lithium-rich polymorphs have not been described yet even Li-rich phase may show better electrochemical properties than conventional LiTi2(PO4)3 at the expense of somewhat lowered capacity. We have synthesized orthorhombic Li1.5Ti2(PO4)3 (OLTP) and rhombohedral LiTi2(PO4)3 (RLTP) via sol-gel reactions and studied their fundamental electrochemical properties using galvanostatic charge/discharge and cyclic voltammetry (CV). Their feasibility as anode materials in LiFePO4//LixTi2(PO4)3 configurations using aqueous electrolytes were also considered. The faster kinetics of the orthorhombic lithium titanium phosphate in this study were attributed to higher Li+ diffusivity and electrical conductivity, making this material an attractive alternative for conventional rhombohedral LiTi2(PO4)3

  8. SYNTHESIS OF NANO-ZnO PARTICLES FOR ALUMINUM METALLURGY AS INERT ANODE MATERIAL

    Institute of Scientific and Technical Information of China (English)

    A.A.A. Saleh; Y. Fu; X.J. Zhai; Y.C. Zhai; M.M. Elomella; A.L. Zhang

    2004-01-01

    Nano-ZnO particle was produced by evaporating zinc powders in air at air flow-rate from 0.2 to 0.6m3/h. Nano-ZnO particles was formed by the oxidation of the evaporated zinc vapor. X-ray diffraction shows the powders to be ZnO with lattice parameters of a=0.3249nm and c=0.5205nm. The particle size is dependent upon the transit time from the source to the collection area. The size of particles was ranged between 81 to 103nm. The average density resulted was 4.865g/cm3.Normal ZnO and nano-ZnO were investigated to use them in aluminum metallurgy as an inert anode material. A certain amount of both oxides were molded subsequently inserted to the molten cryolite-aluminum oxide to investigate the corrosive behavior of both oxides. When the sintering temperature increased up to 1300 ℃, the weight loss ratio rose to 5.01%-7.33% and up to 7.67%-10.18% for nano-ZnO and normal ZnO, respectively. However, when the samples in the molten cryolite aluminum oxide were put for long time, the corrosive rate was found to be higher. It was found that the corrosive loss weight ratio of nano-ZnO anode was much lower than the normal one made from ordinary-ZnO providing that the nano-ZnO is more possible to be use inert anode material.

  9. Fabrication of highly ordered porous nickel oxide anode materials and their electrochemical characteristics in lithium storage

    International Nuclear Information System (INIS)

    Highlights: • NiO/Si-MCP nanocomposites electrocatalysts as anodes in lithium ion batteries. • Si MCP itself is an excellent support for electrocatalyst. • The structure with high surface to volume ratio endows higher mass NiO nanopatricles. • The ordered channel and mesoporous structure permits liquid electrolyte flow easily. • This research may provide a meaning way in integratable lithium-ion batteries. - Abstract: The structure and electrochemical properties of silicon microchannel plates (MCP)-supported NiO nanocomposites (NiO/Si-MCP) synthesized by silicon micromachining, electroless plating, and thermal annealing are investigated as anodes in lithium ion batteries. Galvanostatic charge and discharge results indicate that the NiO/Si-MCP is capable of delivering a higher capacity than the bare nickel-oxide film. At a 1 C current, the NiO/Si-MCP nanocomposite film shows an enormous first discharge capacity of about 3190 mA g−1 and charge capacity of 1977 mA g−1. After 15 cycles, the NiO/Si-MCP nanocomposite retains a reversible capacity of 1531 mA g−1 with 63.7% of the capacity maintained in the 2nd cycle. The lithium storage capacity is maintained at ∼880 mA h g−1 after 50 discharge/charge cycles and it is much larger than that of NiO and its composites. The enhanced electrochemical performance of the highly ordered three-dimensional materials is attributed to the synergistic effects offered by the silicon microchannel plates in the nickel oxide film subsequently facilitating electrolyte penetration, diffusion, and migration. The structure is promising anode materials in lithium-ion batteries

  10. Hematite nanoflakes as anode electrode materials for rechargeable lithium-ion batteries

    International Nuclear Information System (INIS)

    Hematite (α-Fe2O3) nanoflakes and nanocubes were synthesized by liquid-solid-solution method and their properties as anode electrode materials for rechargeable Li+-ion batteries were measured. When changing the water to ethanol volume ratio in the synthesis system, the nanocrystals can be changed from α-Fe2O3 to α-FeOOH, with shapes being tuned from nanoflakes to nanocubes, non-uniform particles and nanowires. When assembled as the anode electrode materials in rechargeable Li+-ion batteries, the hematite nanoflakes showed one more plateau in the first discharge progress of the voltage-composition curves than hematite nanocrystals with other shapes in the literature. X-ray diffraction, high-resolution transmission electron microscope and electrochemical data showed that this extra plateau came from the formation of Li2Fe3O4 nanoclusters and amorphous Li2O. This experiment showed that like sizes, shapes of nanocrystals may also affect the detailed electrochemical progress.

  11. The electrochemical performance of nickel chromium oxide as a new anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Highlights: • NiCr2O4 is fabricated and used as a new anode material for lithium ion batteries. • NiCr2O4 electrode is prepared via a facile and low cost way. • the NiCr2O4 electrode undergoes a novel electrochemical reconstruction in cycling. • the NiCr2O4 electrode exhibits good electrochemical performance. - Abstract: NiCr2O4 is successfully prepared via hydrothermal pretreatment and subsequent sintering, which shows excellent electrochemical performance as a new anode material for lithium ion batteries with natural graphite adding and sodium alginate binder. At a specific current of 70 mA g−1, it delivers charge and discharge capacities of 465.5 and 919.8 mAh g−1 in the initial cycle, which gradually increases along with cycle number owing to an electrochemical reconstruction in cycling. After 100 cycles, the charge and discharge capacities are 582.9 and 592.5 mAh g−1, respectively. Furthermore, it is testified that natural graphite adding can effectively improve the electronic conductivity of the NiCr2O4 electrode, and an appropriate amount of natural graphite is beneficial to improve the specific capacity and cycle stability of the electrode owing to a coordinated electrochemical reconstruction between NiCr2O4 and natural graphite in cycling

  12. Vacuum arc anode phenomena

    International Nuclear Information System (INIS)

    A brief review of anode phenomena in vacuum arcs is presented. Discussed in succession are: the transition of the arc into the anode spot mode; the temperature of the anode before, during and after the anode spot forms; and anode ions. Characteristically the anode spot has a temperature of the order of the atmospheric boiling point of the anode material and is a copious source of vapor and energetic ions. The dominant mechanism controlling the transition of the vacuum arc into the anode spot mode appears to depend upon the electrode geometry, the electrode material, and the current waveform of the particular vacuum arc being considered. Either magnetic constriction in the gap plasma or gross anode melting can trigger the transition; indeed, a combination of the two is a common cause of anode spot formation

  13. Anode material selection criteria for selective oxidation of inorganic compounds in nitric acid media

    International Nuclear Information System (INIS)

    Significant progress has been made since the 19606 in developing highly effective anode materials for electrochemical processes, The problem areas currently facing electrochemistry researchers include investigating new composite materials obtained by grafting or doping, improving fabrication techniques to extend the lifetime of the materials while maintaining their selectivity, studying their electrochemical properties and relating them to the material structure. Research on materials with high oxygen over-potentials-materials on which water oxidation is kinetically affected, and which open an electro-activity window on high potentials (2.0 VESH or greater) - has opened new avenues such as the use of various metallic oxide deposits. Two oxide classes were identified from a structural standpoint on the basis of their water oxidation properties: chemisorbed active oxygen anodes (e.g. PtOx, IrO2 or RuO2) and physi-sorbed active oxygen anodes (e.g. SnO2 or PbO2). Selective electrochemical generation of powerful oxidants between 1.4 and 2.0 VESH in concentrated nitric acid media is used in the context of the nuclear fuel cycle, and the potential advantages of new materials with a high oxygen over-potential-other than widely used platinum-have attracted attention. The relevant physical, chemical and electrochemical properties of such materials were therefore investigated to assess their selective oxidation performance. The study focused in particular on identifying the specific aspects of concentrated nitric acid media in the processes occurring at the electrode/solution interface, using linear and cyclic voltammetry, imposed-potential electrolysis and impedance spectroscopy. This approach allowed characterization of the electron charge transfer kinetics of the medium (nitric acid, compared with other acids such as methane sulfonic acid) and of the selected redox couple (Ag(II)/Ag(I) in this case). The tests covered a wide range of materials, including IrO2, SnO2, PbO2

  14. Structures, phase stabilities, and electrical potentials of Li-Si battery anode materials

    KAUST Repository

    Tipton, William W.

    2013-05-28

    The Li-Si materials system holds promise for use as an anode in Li-ion battery applications. For this system, we determine the charge capacity, voltage profiles, and energy storage density solely by ab initio methods without any experimental input. We determine the energetics of the stable and metastable Li-Si phases likely to form during the charging and discharging of a battery. Ab initio molecular dynamics simulations are used to model the structure of amorphous Li-Si as a function of composition, and a genetic algorithm coupled to density-functional theory searches the Li-Si binary phase diagram for small-cell, metastable crystal structures. Calculations of the phonon densities of states using density-functional perturbation theory for selected structures determine the importance of vibrational, including zero-point, contributions to the free energies. The energetics and local structural motifs of these metastable Li-Si phases closely resemble those of the amorphous phases, making these small unit cell crystal phases good approximants of the amorphous phase for use in further studies. The charge capacity is estimated, and the electrical potential profiles and the energy density of Li-Si anodes are predicted. We find, in good agreement with experimental measurements, that the formation of amorphous Li-Si only slightly increases the anode potential. Additionally, the genetic algorithm identifies a previously unreported member of the Li-Si binary phase diagram with composition Li5Si2 which is stable at 0 K with respect to previously known phases. We discuss its relationship to the partially occupied Li7Si3 phase. © 2013 American Physical Society.

  15. Li4Ti5O12-coated graphite anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Nano-sized Li4Ti5O12 (LTO)-coated graphite core–shell prepared by sol–gel process. • LTO-coated graphite is used in Li-ion battery to improve the cycle life under 55 °C. • Graphite coated with LTO shows smaller resistance than graphite after cell cycling. • The LTO coating suppress the disorder of SP2 structure in graphite during cycling. • Resistance and structure stabilization results in good cycle life of the Li-ion cell. - Abstract: In this study, we synthesized and characterized Li4Ti5O12 (LTO)-coated graphite as an anode material for Li-batteries. The surface of graphite powders was uniformly coated by the LTO nanoparticles to form a core–shelled structure via a sol–gel process, followed by calcination. The average size of graphite core was 20 μm while the thickness of LTO shell was 60 nm to 100 nm. We found that LTO-coated graphite has better rate-capability and cycle life at RT and 55 °C, compared with the pristine graphite. The electrochemical impedance spectroscopy (EIS) results of the cell with LTO-coated graphite anode showed a significant suppression of the impedance rise after 60 cycles. In addition, the Raman spectrum showed that after 60 charge–discharge cycles at 55 °C, the ID/IG ratio of the LTO-coated graphite electrode increased slightly, while that of the pristine graphite electrode increased significantly. The batteries with LTO-coated graphite anode exhibited excellent cyclic ability and high temperature performance

  16. Microscopic properties of lithium, sodium, and magnesium battery anode materials related to possible dendrite growth

    International Nuclear Information System (INIS)

    Lithium and magnesium exhibit rather different properties as battery anode materials with respect to the phenomenon of dendrite formation which can lead to short-circuits in batteries. Diffusion processes are the key to understanding structure forming processes on surfaces. Therefore, we have determined adsorption energies and barriers for the self-diffusion on Li and Mg using periodic density functional theory calculations and contrasted the results to Na which is also regarded as a promising electrode material in batteries. According to our calculations, magnesium exhibits a tendency towards the growth of smooth surfaces as it exhibits lower diffusion barriers than lithium and sodium, and as an hcp metal it favors higher-coordinated configurations in contrast to the bcc metals Li and Na. These characteristic differences are expected to contribute to the unequal tendencies of these metals with respect to dendrite growth

  17. Preparation and Characterization of Carbon Coated Silicon Nanoparticle as Anode Material for Li-ion Batteries

    Institute of Scientific and Technical Information of China (English)

    T. Zhancg; L.J. Fu; J. Gao; Y. P. Wu; H.Q. Wu

    2005-01-01

    @@ 1Introduction Silicon has been regarded as one of the most promising anode materials for Li-ion batteries. Its theoretical capacity (4 000 mAh/g) is much higher than that of the commercialized graphite (372 mAh/g)[1]. However,the cycle performance of silicon is poor due to the severe volume expansion and shrinkage during Li+ insertion/extraction which results in pulverization of Si particles, eventually losing its Li+ storage ability[2]. To solve this problem, nanosized Si particles were utilized and achieved a partial improvement by reducing the absolute volume change. Nevertheless, a new problem was encountered with nanosized material that small Si particles were aggregated to be larger one during Li+ insertion/extraction, and then pulverized again[3]. In this work, we have succeeded to improve the cycle performance of nanosized Si particles by synthesis of carbon coated silicon nanoparticle.

  18. Electron beam modification of anode materials for high-rate lithium ion batteries

    Science.gov (United States)

    Park, Yiseul; Park, Jung Soo; Baek, Seong-Ho; Kim, Jae Hyun

    2015-11-01

    The rate capability of a Li4Ti5O12 (LTO)-based anode in a lithium ion battery can be easily improved by electron beam (EB) irradiation without the need for complicated synthetic procedures. The electrode prepared with EB-irradiated LTO at a 50 kGy dose has an enhanced rate capability while retaining a discharge capacity of 100 mAh g-1, even at the 20 C-rate. The effect of EB irradiation on the properties of the anode materials (i.e., LTO, poly(vinylidene fluoride) (PVDF), super P carbon) is examined in detail through systematic experiments. Both LTO and PVDF are affected by EB irradiation and dependent on the exposed electron dose, but super P is affected negligibly. EB irradiation partially reduces LTO with forming Tix+ (2 < x < 4) which is attributed to the enhanced electrical conductivity. EB irradiation causes dehydrofluorination and cross-linking in PVDF, resulting in the formation of carbon-carbon double bonds. The conjugated structure of PVDF is formed by the further dehydrofluorination during mixing with LTO via ball-milling, and this is accelerated in the presence of EB-PVDF. This conjugated structure enhances the electrical conductivity and is responsible for the improved rate capability.

  19. Hollow Fe3O4 microspheres as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    In this study, we proposed a unique method for hollow Fe3O4 microspheres and confirmed their electrochemical properties as anode materials for lithium-ion batteries. Poly(MAA/EGDMA)/Fe3O4 core–shell microspheres were prepared by simple ionic attraction between hydrogel microspheres with negative charge and magnetic Fe3O4 nanoparticles under alkaline conditions. The poly(MAA/EGDMA) core spheres were removed by heat treatment in order to form the hollow structure of Fe3O4 microspheres. Their hollow structure prevents cracking of the electrode during the volume change of repetitive Li-ion insertion and extraction reactions and improves the Li-ion transfer during cycling. The morphologies and structure of the hollow Fe3O4 microspheres were confirmed by scanning electron microscopy, focused ion beam-scanning electron microscopy, transmission electron microscopy, optical microscopy and X-ray diffraction. The electrochemical performance of the composite electrode was evaluated by constant current charging and discharging, cyclic voltammetry and cycling performance at various cycling rates. The results showed excellent cycle stability compared with a composite electrode containing bare Fe3O4 nanoparticles. These results indicate that the unique structures of Fe3O4 microspheres contribute to the excellent life and high reversible capacity of the battery when they are used as an anode of a lithium-ion battery.

  20. Composit, Nanoparticle-Based Anode material for Li-ion Batteries Applied in Hybrid Electric (HEV's)

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Malgorzata Gulbinska

    2009-08-24

    Lithium-ion batteries are promising energy storage devices in hybrid and electric vehicles with high specific energy values ({approx}150 Wh/kg), energy density ({approx}400 Wh/L), and long cycle life (>15 years). However, applications in hybrid and electric vehicles require increased energy density and improved low-temperature (<-10 C) performance. Silicon-based anodes are inexpensive, environmentally benign, and offer excellent theoretical capacity values ({approx}4000 mAh/g), leading to significantly less anode material and thus increasing the overall energy density value for the complete battery (>500 Wh/L). However, tremendous volume changes occur during cycling of pure silicon-based anodes. The expansion and contraction of these silicon particles causes them to fracture and lose electrical contact to the current collector ultimately severely limiting their cycle life. In Phase I of this project Yardney Technical Products, Inc. proposed development of a carbon/nano-silicon composite anode material with improved energy density and silicon's cycleability. In the carbon/nano-Si composite, silicon nanoparticles were embedded in a partially-graphitized carbonaceous matrix. The cycle life of anode material would be extended by decreasing the average particle size of active material (silicon) and by encapsulation of silicon nanoparticles in a ductile carbonaceous matrix. Decreasing the average particle size to a nano-region would also shorten Li-ion diffusion path and thus improve rate capability of the silicon-based anodes. Improved chemical inertness towards PC-based, low-temperature electrolytes was expected as an additional benefit of a thin, partially graphitized coating around the active electrode material.

  1. Investigation of Metal Oxide/Carbon Nano Material as Anode for High Capacity Lithium-ion Cells

    Science.gov (United States)

    Wu, James Jianjun; Hong, Haiping

    2014-01-01

    NASA is developing high specific energy and high specific capacity lithium-ion battery (LIB) technology for future NASA missions. Current state-of-art LIBs have issues in terms of safety and thermal stability, and are reaching limits in specific energy capability based on the electrochemical materials selected. For example, the graphite anode has a limited capability to store Li since the theoretical capacity of graphite is 372 mAh/g. To achieve higher specific capacity and energy density, and to improve safety for current LIBs, alternative advanced anode, cathode, and electrolyte materials are pursued under the NASA Advanced Space Power System Project. In this study, the nanostructed metal oxide, such as Fe2O3 on carbon nanotubes (CNT) composite as an LIB anode has been investigated.

  2. Efficient Natural Dye-Sensitized Solar Cells Based on Spin-Coated TiO2 Anode Materials

    Science.gov (United States)

    Yu, Xiao-Hong; Sun, Zhao-Zong; Lian, Jie; Li, Yi-Tan; Chen, Yan-Xue; Gao, Shang; Wang, Xiao; Wang, Ying-Shun; Zhao, Ming-Lin

    2013-11-01

    TiO2 anode materials are prepared on ITO glass by spin-coated method. Dye-sensitized solar cells are assembled with these anodes and natural dyes extracted from radix ophiopogonis by different solvents. The formation and characterization of anode materials are confirmed by field-emission scanning electron microscopy, x-ray diffraction, UV-visible absorption spectroscopy. Photovoltaic testing results show that energy conversion efficiency could reach 1.67% with fill factor of 0.51, open-circuit voltage of 457 mV, and short-circuit photocurrent density of 7.2 mA/cm2. The short-circuit photocurrent density can reach 7.6 mA/cm2 with efficiency of 1.33.

  3. Electrodeposited gold nanoparticles on carbon nanotube-textile: Anode material for glucose alkaline fuel cells

    KAUST Repository

    Pasta, Mauro

    2012-06-01

    In the present paper we propose a new anode material for glucose-gluconate direct oxidation fuel cells prepared by electrodepositing gold nanoparticles onto a conductive textile made by conformally coating single walled carbon nanotubes (SWNT) on a polyester textile substrate. The electrodeposition conditions were optimized in order to achieve a uniform distribution of gold nanoparticles in the 3D porous structure of the textile. On the basis of previously reported studies, the reaction conditions (pH, electrolyte composition and glucose concentration) were tuned in order to achieve the highest oxidation rate, selectively oxidizing glucose to gluconate. The electrochemical characterization was carried out by means of cyclic voltammetry. © 2012 Elsevier B.V. All rights reserved.

  4. Properties and microstructure of NiO/SDC materials for SOFC anode applications

    Institute of Scientific and Technical Information of China (English)

    CHENG Jigui; DENG Liping; ZHANG Benrui; SHI Ping; MENG Guangyao

    2007-01-01

    NiO/SDC composites and Ni/SDC cermets for solid oxide fuel cell (SOFC) anode applications were prepared from nickel oxide (NiO) and samaria doped ceria (SDC) powders by the powder metallurgy process. The physical and mechanical properties, as well as the microstructure of the NiO/SDC composites and the Ni/SDC cermets were investigated. It is shown that the sintering temperature of the NiO/SDC composites and NiO content plays an important role in determining the microstructure and properties of the NiO/SDC composites, which, in turn, influences the microstructure, electrical conductivity, and mechanical properties of the Ni/SDC cermets. The present study demonstrated that composition and tprocess parameters must be appropriately selected to optimize the microstructure and the properties of NiO/SDC materials for solid oxide fuel cell applications.

  5. Dead lithium phase investigation of Sn-Zn alloy as anode materials for lithium ion battery

    Institute of Scientific and Technical Information of China (English)

    HUANG ZhaoWen; HU SheJun; HOU XianHua; RU Qiang; YU HongWen; ZHAO LingZhi; LI WeiShan

    2009-01-01

    In this work, based on First-principle plane wave pseudo-potential method, we have carried out an in-depth study on the possible dead lithium phase of Sn-Zn alloy as anode materials for lithium ion batteries. Through investigation, we found that the phases LixSn4Zn4(x = 2, 4, 6, 8) contributed to reversible capacity, while the phases LixSn4Zns-(x-4)(x = 4.74, 7.72) led to capacity loss due to high formation energy, namely, they were the dead lithium phases during the charge/discharge process. And we come up with a new idea that stable lithium alloy phase with high lithiation formation energy (dead lithium phase) can also result in high loss of active lithium ion, besides the traditional expression that the formation of solid electrolyte interface film leads to high capacity loss.

  6. Mechanism of lithium insertion into NiSi2 anode material for lithium ion batteries

    Institute of Scientific and Technical Information of China (English)

    WEN Zhongsheng; JI Shijun; SUN Juncai; TIAN Feng; TIAN Rujin; XIE Jingying

    2006-01-01

    As a promising high capacity anode material for lithium ion batteries, the lithium insertion performance and possible insertion mechanism of binary alloy of NiSi2 were discussed. The initial lithium insertion of crystal NiSi2 can reach up to 600 mAh·g-1 , but large irreversible capacity occurrs simultaneously for serious structure transformation and the irreversible phase forms. XRD and XPS were employed to detect the crystal structure and composition changes produced by lithium insertion. The lithium insertion-extraction behavior of NiSi2 electrode is similar to that of silicon after the first discharge. The structure stability seems related to the non-stoichimometric Ni-Si compound formed by lithium insertion into NiSi2.

  7. Effect of the synthesis method of SnSb anode materials on their electrochemical properties

    Institute of Scientific and Technical Information of China (English)

    Chaoli Yin; Hailei Zhao; Hong Guo; Xianliang Huang; Weihua Qiu

    2007-01-01

    SnSb alloy powders for the anode of Li-ion batteries were synthesized by two kinds of reduction precipitation methods:solution titration and rapid mixing. Two kinds of SnSb alloy powders showed different phase compositions and particle morphologies although the same starting materials were used. The SnSb alloy electrode synthesized by titration exhibits high reversible specific capacity and good cycling stability, whereas the rapid-mixing sample shows high irreversible capacity and fast capacity fade. The broad particle size distribution of SnSb powders synthesized by titration is considered to be responsible for the improvement of cycling stability. The initial charge-discharge efficiency exceeding 80% has been obtained for the titration sample. The electrochemical reaction process of two kinds of synthesized SnSb composite electrodes was characterized by cyclic voltammetry and AC impedance techniques.

  8. Corrosion rate of construction materials in hot phosphoric acid with the contribution of anodic polarization

    DEFF Research Database (Denmark)

    Kouril, M.; Christensen, Erik; Eriksen, S.;

    2011-01-01

    The paper is focused on selection of a proper material for construction elements of water electrolysers, which make use of a 85% phosphoric acid as an electrolyte at temperature of 150 8C and which might be loaded with anodic polarization up to 2.5 V versus a saturated Ag/AgCl electrode (SSCE......% phosphoric acid at 150 8C and at polarization of 2.5 V/SSCE is tantalum. In that case, even a gentle cathodic polarization is harmful in such an acidic environment. Hydrogen reduction leads to tantalum hydride formation, to loss of mechanical properties and to complete disintegration of the metal. Contrary...... to tantalum, titanium is free of any corrosion resistance in hot phosphoric acid. Its corrosion rate ranges from tens of millimetres to metres per year depending on temperature of the acid. Alloy bonded tantalum coating was recognized as an effective corrosion protection for both titanium and stainless steel...

  9. Nb2O5 hollow nanospheres as anode material for enhanced performance in lithium ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: Nb2O5 hollow nanosphere constructed electrode delivers high capacity of 172 mAh g−1 after 250 cycles and maintains structural integrity and excellent cycling stability. Highlights: ► Nb2O5 hollow nanospheres synthesis was synthesized by soft-template. ► Nb2O5 hollow nanospheres were investigated as anode material in Li-ion battery. ► Nanostructured electrode delivers high capacity of 172 mAh g−1 after 250 cycles. ► The electrode maintains the structural integrity and excellent cycling stability. ► Nanosized shell domain facilitates fast lithium intercalation/deintercalation. -- Abstract: Nb2O5 hollow nanospheres of average diameter ca. ∼29 nm and hollow cavity size ca. 17 nm were synthesized using polymeric micelles with core–shell–corona architecture under mild conditions. The hollow particles were thoroughly characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), infrared spectroscopy (FTIR), thermal (TG/DTA) and nitrogen adsorption analyses. Thus obtained Nb2O5 hollow nanospheres were investigated as anode materials for lithium ion rechargeable batteries for the first time. The nanostructured electrode delivers high capacity of 172 mAh g−1 after 250 cycles of charge/discharge at a rate of 0.5 C. More importantly, the hollow particles based electrodes maintains the structural integrity and excellent cycling stability even after exposing to high current density 6.25 A g−1. The enhanced electrochemical behavior is ascribed to hollow cavity coupled with nanosized Nb2O5 shell domain that facilitates fast lithium intercalation/deintercalation kinetics.

  10. Onion-like carbon coated CuO nanocapsules: A highly reversible anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Onion-like carbon–coated CuO nanocapsules have been synthesized. • Onion-like carbon leads to the improved stability and electric conductivity. • CuO/C nanocapsules maintain a reversible capacity of 628.7 mA h g−1 after 50 cycles. -- Abstract: The synthesis and characterization of CuO/C nanocapsules for application as anode material in lithium ion batteries are reported. Introduction of onion-like carbon shell on the CuO nanoparticles leads to the improved stability, electric conductivity and electrochemical performance. When evaluated as potential anode materials for lithium-ion batteries, the novel CuO/C nanocapsules deliver an initial discharge capacity of 1043.9 mA h g−1 at 100 mA g−1 and maintain a high reversible capacity of 628.7 mA h g−1 after 50 charge–discharge cycles, much higher than those of the CuO nanoparticles. A postmortem analysis of the CuO and CuO/C anodes subjected to prolonged cycling reveals the existence of a lower degree of surface cracking and particle breakage in the CuO/C anode than the CuO anode

  11. Onion-like carbon coated CuO nanocapsules: A highly reversible anode material for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xianguo, E-mail: liuxianguohugh@gmail.com [Anhui Key Laboratory of Metal Materials and Processing, School of Materials Science and Engineering, Anhui University of Technology, Maanshan 243002 (China); Bi, Nannan; Feng, Chao [Anhui Key Laboratory of Metal Materials and Processing, School of Materials Science and Engineering, Anhui University of Technology, Maanshan 243002 (China); Or, Siu Wing [Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Sun, Yuping [Center for Engineering practice and Innovation Education, Anhui University of Technology, Maanshan 243002 (China); Jin, Chuangui; Li, Weihuo; Xiao, Feng [Anhui Key Laboratory of Metal Materials and Processing, School of Materials Science and Engineering, Anhui University of Technology, Maanshan 243002 (China)

    2014-02-25

    Highlights: • Onion-like carbon–coated CuO nanocapsules have been synthesized. • Onion-like carbon leads to the improved stability and electric conductivity. • CuO/C nanocapsules maintain a reversible capacity of 628.7 mA h g{sup −1} after 50 cycles. -- Abstract: The synthesis and characterization of CuO/C nanocapsules for application as anode material in lithium ion batteries are reported. Introduction of onion-like carbon shell on the CuO nanoparticles leads to the improved stability, electric conductivity and electrochemical performance. When evaluated as potential anode materials for lithium-ion batteries, the novel CuO/C nanocapsules deliver an initial discharge capacity of 1043.9 mA h g{sup −1} at 100 mA g{sup −1} and maintain a high reversible capacity of 628.7 mA h g{sup −1} after 50 charge–discharge cycles, much higher than those of the CuO nanoparticles. A postmortem analysis of the CuO and CuO/C anodes subjected to prolonged cycling reveals the existence of a lower degree of surface cracking and particle breakage in the CuO/C anode than the CuO anode.

  12. Sodium Titanium Phosphate as Anode Materials for Aqueous Sodium-ion Batteries

    Science.gov (United States)

    Wu, Wei

    Renewable energy technology has become one of the promising energy solutions in the future. However, limited by their cyclic behavior, large scale energy storage devices are needed to boost their adoptions in the market. The existing energy storage technologies have limitations that inhibit their adoptions for large scale applications. Our group suggests that one reasonable technology that might overcome these issues is the neutral pH aqueous electrolyte sodium-ion battery. One potential anode material is NaTi2(PO4)3, which has a relatively flexible NASICON skeleton structure and is known in general to have stable performance characteristics in extreme environments. In this work, there are four objectives to study this potential anode material: 1) Develop a rapid method to synthesize electrochemically functional NaTi2(PO4)3. In this case "Electrochemically functional" means the material can store usable capacity for practical application in a composite electrode. 2) Quantify the effect of intimate carbon on NaTi2(PO4)3 electrochemical functionality. (Electrochemical functionality regards the capacity and rate capability of electrode materials) 3) Investigate the stability of NaTi2(PO 4)3 in pH and thermal extremes and the mechanism of capacity fading under different cycling conditions. 4) Examine the performance of NaTi 2(PO4)3 in high salt concentration electrolyte and Li+ electrolyte. NaTi2(PO4)3 has been successfully synthesized via a rapid microwave method. The highest specific capacity is around 85mAh/g has been demonstrated. The effect of different carbon materials (namely graphite and carbon nanotubes) and different processes of adding them (pre and post- synthesis) on the electrochemical performance for sodium titanium phosphate has been extensively studied. Graphite coated NaTi2(PO4) 3 with carbon nanotubes composite electrode has demonstrated a specific capacity of 130mAh/g around theoretical value at 0.1C rate. The effect of the electrolyte (with

  13. Green synthesis of boron doped graphene and its application as high performance anode material in Li ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Sahoo, Madhumita; Sreena, K.P.; Vinayan, B.P.; Ramaprabhu, S., E-mail: ramp@iitm.ac.in

    2015-01-15

    Graphical abstract: Boron doped graphene (B-G), synthesized by simple hydrogen induced reduction technique using boric acid as boron precursor, have more uneven surface as a result of smaller bonding distance of boron compared to carbon, showed high capacity and high rate capability compared to pristine graphene as an anode material for Li ion battery application. - Abstract: The present work demonstrates a facile route for the large-scale, catalyst free, and green synthesis approach of boron doped graphene (B-G) and its use as high performance anode material for Li ion battery (LIB) application. Boron atoms were doped into graphene framework with an atomic percentage of 5.93% via hydrogen induced thermal reduction technique using graphite oxide and boric acid as precursors. Various characterization techniques were used to confirm the boron doping in graphene sheets. B-G as anode material shows a discharge capacity of 548 mAh g{sup −1} at 100 mA g{sup −1} after 30th cycles. At high current density value of 1 A g{sup −1}, B-G as anode material enhances the specific capacity by about 1.7 times compared to pristine graphene. The present study shows a simplistic way of boron doping in graphene leading to an enhanced Li ion adsorption due to the change in electronic states.

  14. Dual-carbon enhanced silicon-based composite as superior anode material for lithium ion batteries

    Science.gov (United States)

    Wang, Jie; Liu, Dai-Huo; Wang, Ying-Ying; Hou, Bao-Hua; Zhang, Jing-Ping; Wang, Rong-Shun; Wu, Xing-Long

    2016-03-01

    Dual-carbon enhanced Si-based composite (Si/C/G) has been prepared via employing the widely distributed, low-cost and environmentally friendly Diatomite mineral as silicon raw material. The preparation processes are very simple, non-toxic and easy to scale up. Electrochemical tests as anode material for lithium ion batteries (LIBs) demonstrate that this Si/C/G composite exhibits much improved Li-storage properties in terms of superior high-rate capabilities and excellent cycle stability compared to the pristine Si material as well as both single-carbon modified composites. Specifically for the Si/C/G composite, it can still deliver a high specific capacity of about 470 mAh g-1 at an ultrahigh current density of 5 A g-1, and exhibit a high capacity of 938 mAh g-1 at 0.1 A g-1 with excellent capacity retention in the following 300 cycles. The significantly enhanced Li-storage properties should be attributed to the co-existence of both highly conductive graphite and amorphous carbon in the Si/C/G composite. While the former can enhance the electrical conductivity of the obtained composite, the latter acts as the adhesives to connect the porous Si particulates and conductive graphite flakes to form robust and stable conductive network.

  15. Electrical and Mechanical Performance of Carbon Fiber-Reinforced Polymer Used as the Impressed Current Anode Material

    Directory of Open Access Journals (Sweden)

    Ji-Hua Zhu

    2014-07-01

    Full Text Available An investigation was performed by using carbon fiber-reinforced polymer (CFRP as the anode material in the impressed current cathodic protection (ICCP system of steel reinforced concrete structures. The service life and performance of CFRP were investigated in simulated ICCP systems with various configurations. Constant current densities were maintained during the tests. No significant degradation in electrical and mechanical properties was found for CFRP subjected to anodic polarization with the selected applied current densities. The service life of the CFRP-based ICCP system was discussed based on the practical reinforced concrete structure layout.

  16. Synthesis and characterization of SnO-carbon nanotube composite as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    SnO-carbon nanotube composite was synthesized by a sol-gel method. The electrochemical behavior of the composite using an anode active material in lithium-ion batteries was investigated. It was found that the composite showed enhanced anode performance compared with the unsupported SnO or carbon nanotube (CNT). The capacity fade of the composite electrode was reduced over unsupported SnO or CNT. We attribute the results to the conductivity and ductility of the CNT matrix, and the high dispersion of SnO

  17. Micro-sized cadmium tungstate as a high-performance anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • CdWO4 was obtained by a facile and effective precipitation reaction route. • The application of CdWO4 to a lithium-ion battery anode was firstly reported. • The CdWO4 anode delivered a high initial discharge capacity of 2304.1 mA h g−1. • Electrochemical reaction mechanism of CdWO4 with Li was studied by cyclic voltammetry. - Abstract: The application of cadmium tungstate (CdWO4) to a lithium-ion battery anode was firstly reported in this paper. It was prepared by a facile precipitation reaction process. The CdWO4 sample was characterized using X-ray diffraction and scanning electron microscopy. The electrochemical properties of CdWO4 anode were investigated. The CdWO4 delivered a high initial discharge capacity of 2042.4 mA h g−1. The CdWO4/C composite showed an improved electrochemical performance with an initial discharge capacity of 2304.1 mA h g−1 and achieved a discharge capacity of 305.1 mA h g−1 after 19 cycles. Electrochemical reaction mechanism of CdWO4 with Li was also studied by cyclic voltammetry. It is suggested that CdWO4 can be a promising high-capacity anode material for lithium-ion batteries

  18. Caramel popcorn shaped silicon particle with carbon coating as a high performance anode material for Li-ion batteries.

    Science.gov (United States)

    He, Meinan; Sa, Qina; Liu, Gao; Wang, Yan

    2013-11-13

    Silicon is a very promising anode material for lithium ion batteries. It has a 4200 mAh/g theoretical capacity, which is ten times higher than that of commercial graphite anodes. However, when lithium ions diffuse to Si anodes, the volume of Si will expand to almost 400% of its initial size and lead to the crack of Si. Such a huge volume change and crack cause significant capacity loss. Meanwhile, with the crack of Si particles, the conductivity between the electrode and the current collector drops. Moreover, the solid electrolyte interphase (SEI), which is generated during the cycling, reduces the discharge capacity. These issues must be addressed for widespread application of this material. In this work, caramel popcorn shaped porous silicon particles with carbon coating are fabricated by a set of simple chemical methods as active anode material. Si particles are etched to form a porous structure. The pores in Si provide space for the volume expansion and liquid electrolyte diffusion. A layer of amorphous carbon is formed inside the pores, which gives an excellent isolation between the Si particle and electrolyte, so that the formation of the SEI layer is stabilized. Meanwhile, this novel structure enhances the mechanical properties of the Si particles, and the crack phenomenon caused by the volume change is significantly restrained. Therefore, an excellent cycle life under a high rate for the novel Si electrode is achieved. PMID:24111737

  19. Electrically exploded silicon/carbon nanocomposite as anode material for lithium-ion batteries.

    Science.gov (United States)

    Farooq, Umer; Choi, Jeong-Hee; Kim, Doohun; Pervez, Syed Atif; Yaqub, Adnan; Hwang, Min-Ji; Lee, You-Jin; Lee, Won-Jae; Choi, Hae-Young; Lee, Sang-Hoon; You, Ji-Hyun; Ha, Chung-Wan; Doh, Chil-Hoon

    2014-12-01

    In this work, silicon (Si) containing carbon coated core-shell nanostructures were synthesized by electrical explosion of Si wires in ethanol solution followed by high energy mechanical milling (HEMM) process. Material characterization was carried-out using transmission electron microscopy (TEM), field-emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) analysis. HEMM led to very fine and amorphous Si particles in the presence of carbon and inactive Silicon-Carbide (SiC) matrix. These Si based nanocomposites, obtained through electrical explosion followed by HEMM (milled sample), exhibited enhanced electrochemical performance than unmilled nanocomposites, when evaluated as anode material for lithium-ion batteries (LIBs). On completion of (the) 1st cycle, milled and unmilled sample(s) showed specific discharge capacities around 825 mAh/g and 717 mAh/g, respectively. Interestingly, the coulombic efficiencies of milled and unmilled samples were 98.5% and 97% after 60th cycle respectively. The enhanced electrochemical performance is attributed to fine and amorphous Si based nanocomposite obtained through HEMM process. PMID:25971062

  20. Tin-based anode materials with well-designed architectures for next-generation lithium-ion batteries

    Science.gov (United States)

    Liu, Lehao; Xie, Fan; Lyu, Jing; Zhao, Tingkai; Li, Tiehu; Choi, Bong Gill

    2016-07-01

    Tin (Sn) has long been considered to be a promising replacement anode material for graphite in next-generation lithium-ion batteries (LIBs), because of its attractive comprehensive advantages of high gravimetric/volumetric capacities, environmental benignity, low cost, high safety, etc. However, Sn-based anodes suffer from severe capacity fading resulting mainly from their large volume expansions/contractions during lithiation/delithiation and subsequent pulverization, coalescence, delamination from current collectors, and poor Li+/electron transport. To circumvent these issues, a number of extraordinary architectures from nanostructures to anchored, layered/sandwich, core-shell, porous and even integrated structures have been exquisitely constructed to enhance the cycling performance. To cater for the rapid development of Sn-based anodes, we summarize the advances made in structural design principles, fabrication methods, morphological features and battery performance with focus on material structures. In addition, we identify the associated challenges and problems presented by recently-developed anodes and offer suggestions and perspectives for facilitating their practical implementations in next-generation LIBs.

  1. Anode-supported ScSZ-electrolyte SOFC with whole cell materials from combined EDTA-citrate complexing synthesis process

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Hongxia; Ran, Ran; Zhou, Wei; Shao, Zongping [State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, No. 5 Xing Mofan Road, Nanjing, JiangSu 210009 (China)

    2007-10-25

    The potential application of combined EDTA-citrate complexing process (ECCP) in intermediate-temperature solid-oxide fuel cells (IT-SOFCs) processing was investigated. ECCP-derived scandia-stabilized-zirconia (ScSZ) powder displayed low packing density, high surface area and nano-crystalline, which was ideal material for thin-film electrolyte fabrication based on dual dry pressing. A co-synthesis of NiO + ScSZ anode based on ECCP was developed, which showed reduced NiO(Ni) and ScSZ grain sizes and improved homogeneity of the particle size distribution, as compared with the mechanically mixed NiO + ScSZ anode. Anode-supported ScSZ electrolyte fuel cell with the whole cell materials synthesized from ECCP was successfully prepared. The porous anode and cathode exhibited excellent adhesion to the electrolyte layer. Fuel cell with 30 {mu}m thick ScSZ electrolyte and La{sub 0.8}Sr{sub 0.2}MnO{sub 3} cathode showed a promising maximum peak power density of 350 mW cm{sup -2} at 800 C. (author)

  2. Facile synthesis of multilayer-like Si thin film as high-performance anode materials for lithium-ion batteries

    Science.gov (United States)

    Wang, Mingxu; Geng, Zhongrong

    2016-05-01

    For the silicon anodes in lithium-ion batteries, it is well known that the enormous volumetric expansion/contraction is also the mainly reason for the capacity fading. In this manuscript, a new kind of Si thin films was prepared with a radio frequency magnetron sputtering method. By using a periodic modulation negative bias on the substrate, a density-modulated multilayer-like silicon thin films with different layer densities were used as anode materials of lithium-ion batteries, and which displayed a high capacity and stable cycling performances. The reason for the charming electrochemical performances may be owned to the particular density modulated microstructure of the Si thin films. It is conjectured that the lower density can as compliant layers and which provided the volume for the higher-density layer expansion in the process of the lithiation/delithiation. In contrast to the conventional silicon anodes, the density modulated microstructure in this work could exploit a new approach to silicon thin-film anode materials with outstanding electrochemical properties and mechanical stability. And these reports may be provide a new way to prepare the Si thin films for the high-energy, safe, and low-cost batteries.

  3. High lithium electroactivity of electrospun CuFe2O4 nanofibers as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: Electrospun CuFe2O4 nanofibers were used as anode material for lithium-ion batteries for the first time. - Highlights: • We successfully synthesized electrospun CuFe2O4 nanofibers anode material for lithium-ion batteries for the first time. • The as-prepared CuFe2O4 nanofibers calcined at 800 °C exhibited a high initial discharge capacity of 1226.0 mAh g−1, and maintained a stable capacity of 572.4 mAh g−1 after 50 cycles. • The as-prepared CuFe2O4 nanofibers calcined at 800 °C also showed high capacity at higher discharge and charge rate. - Abstract: In this study, copper ferrite (CuFe2O4) nanofibers were successfully fabricated by a combination of electrospinning and calcination process. The crystal structure was investigated by X-ray diffractomentry, and the results show only peaks of CuFe2O4 could be observed from the product obtained at 800 °C, indicating the formation of pure compound. SEM and TEM images showed the as-spun CuFe2O4 nanofibers possessed good continuous fiber morphology with an average diameter of about 66 nm. The electrochemical properties of electrospun CuFe2O4 nanofibers as anode material for lithium-ion batteries were discussed for the first time. The results demonstrated that the electrospun CuFe2O4 nanofibers anode exhibited a high initial discharge capacity of 1226.0 mAh g−1, and maintained a stable capacity of 572.4 mAh g−1 after 50 cycles. Meanwhile, the electrodes showed high capacity at higher discharge and charge rate. The excellent electrochemical properties of electrospun CuFe2O4 nanofibers anode were attributed to the high crystallinity, as well as the unique mesoporous and fibrous structures

  4. Evaluation and performance improvement of Si/SiOx/C based composite as anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    The structure and electrochemical performances of Si/SiOx/C (SSC) and graphite-SSC composite (G-SSC) are evaluated in half cells and full cells as anode materials for lithium ion batteries. It is found that the SSC material shows a lithium storage capacity of 3 to 5 times higher than that of pure graphite while the G-SSC composite exhibits a desirable cycling stability (+80%@400cycles). Structural characterization reveals no particle cracks in the G-SSC composite. The Si particle is surrounded with lithium silicates, which provide protection against the electrolyte invasion and electrolyte decomposition but permits the Li+ ions to pass through. The graphite coating layer, on the other hand, acts as an electric conductive connector and volume buffer. These structural features make the SSC and G-SSC attractive as anode materials for high-performance commercial lithium ion batteries

  5. Revisiting Surface Modification of Graphite: Dual-Layer Coating for High-Performance Lithium Battery Anode Materials.

    Science.gov (United States)

    Song, Gyujin; Ryu, Jaegeon; Ko, Seunghee; Bang, Byoung Man; Choi, Sinho; Shin, Myoungsoo; Lee, Sang-Young; Park, Soojin

    2016-06-01

    Surface modification of electrode active materials has garnered considerable attention as a facile way to meet stringent requirements of advanced lithium-ion batteries. Here, we demonstrated a new coating strategy based on dual layers comprising antimony-doped tin oxide (ATO) nanoparticles and carbon. The ATO nanoparticles are synthesized via a hydrothermal method and act as electronically conductive/electrochemically active materials. The as-synthesized ATO nanoparticles are introduced on natural graphite along with citric acid used as a carbon precursor. After carbonization, the carbon/ATO-decorated natural graphite (c/ATO-NG) is produced. In the (carbon/ATO) dual-layer coating, the ATO nanoparticles coupled with the carbon layer exhibit unprecedented synergistic effects. The resultant c/ATO-NG anode materials display significant improvements in capacity (530 mA h g(-1) ), cycling retention (capacity retention of 98.1 % after 50 cycles at a rate of C/5), and low electrode swelling (volume expansion of 38 % after 100 cycles) which outperform that of typical graphite materials. Furthermore, a full-cell consisting of a c/ATO-NG anode and an LiNi0.5 Mn1.5 O4 cathode presents excellent cycle retention (capacity retention of >80 % after 100 cycles). We envision that the dual-layer coating concept proposed herein opens a new route toward high-performance anode materials for lithium-ion batteries. PMID:27027583

  6. Gallium phosphide as a new material for anodically bonded atomic sensors

    Directory of Open Access Journals (Sweden)

    Nezih Dural

    2014-08-01

    Full Text Available Miniaturized atomic sensors are often fabricated using anodic bonding of silicon and borosilicate glass. Here we describe a technique for fabricating anodically bonded alkali-metal cells using GaP and Pyrex. GaP is a non-birefringent semiconductor that is transparent at alkali-metal resonance wavelengths, allowing new sensor geometries. GaP also has a higher thermal conductivity and lower He permeability than borosilicate glass and can be anodically bonded below 200 °C, which can also be advantageous in other vacuum sealing applications.

  7. Nano-sized Fe3O4/carbon as anode material for lithium ion battery

    International Nuclear Information System (INIS)

    Nano-sized Fe3O4/carbon material is prepared via a simple citric-nitrate combustion method combining with a hydrothermal carbon coating technique. The synthesized Fe3O4/carbon composite shows a high reversible specific capacity (ca. 850 mAh g−1 at 100 mA g−1; ca. 600 mAh g−1 at 500 mA g−1), good rate-capability as well as superior cycling stability as anode for lithium-ion batteries. The ameliorated electrochemical performance of Fe3O4/carbon electrode is associated to the nano-sized particle feature and the continuous carbon coating layer. The former provides short lithium-ion/electron diffusion distance, while the latter enables the fast electron transport pathways. Besides, the carbon layer can act as a protective component to prevent the active particle Fe3O4 from aggregation and pulverization during the charge/discharge processes. - Highlights: • Nano-sized Fe3O4/C was prepared by a simple citric-nitrate combustion process. • Fe3O4/C particles show core–shell structure. • Fe3O4/C powder displays high specific capacity and good cycling stability. • Fe3O4/C composite exhibits a superior rate-capability

  8. Sodium titanate cuboid as advanced anode material for sodium ion batteries

    Science.gov (United States)

    Zhang, Yan; Hou, Hongshuai; Yang, Xuming; Chen, Jun; Jing, Mingjun; Wu, Zhibin; Jia, Xinnan; Ji, Xiaobo

    2016-02-01

    Sodium titanate (Na2Ti6O13) cuboid is successfully prepared and employed for anode electrode materials in sodium-ion batteries (SIBs). Their sodium storage properties are presented by undertaking polyvinylidene fluoride (PVDF), carboxymethyl cellulose (CMC) as different binders. At a current density of 0.1 C, the sodium titanate cuboid with CMC and PVDF exhibits discharge capacity of 269.5 mAh g-1 and 251.0 mAh g-1, respectively. At the 200th charge/discharge cycle, the reserved discharge capacity for Sodium titanate cuboid electrode with CMC binder is 173.6 mAh g-1, amounting to a capacity retention of 94.4%, much higher than that employing PVDF as binder (the discharge capacity of 69.3 mAh g-1 and the capacity retention of 54.1%). The rate capability test and the Coulombic efficiency data also manifest that the Sodium titanate cuboid utilizing CMC as binder is superior to the ones with PVDF. These enhanced electrochemical performance mainly derive from the strong cohesive strength of CMC binder and the swellability of PVDF binder, verifying the importance of a binder to the optimization of sodium storage behavior.

  9. Improvement of thermal stability and safety of lithium ion battery using SiO anode material

    Science.gov (United States)

    Liu, Yi-Hung; Okano, Miki; Mukai, Takashi; Inoue, Kenshi; Yanagida, Masahiro; Sakai, Tetsuo

    2016-02-01

    The thermal stability, in terms of cycle and rate performances at 80 °C, and its safety related to lithium ion batteries composed of a LiFePO4 cathode and SiO anode are investigated. Based on an STEM-EELS analysis, the SiO powder is found to have an amorphous structure, in which nanosized Si particles (Si-rich phase) are uniformly dispersed in the SiO2 matrix (SiO2-rich phase). During the charge/discharge cycling, the cell exhibits a satisfactory cycle performance with a discharge capacity retention of 93.6% and a voltage retention of 93.9% at the 1500th cycle. Also, the charge and discharge capacity retentions at 10 C are 97.5% and 94.7%, respectively, together with a limited polarization, demonstrating its high rate performance. Furthermore, a 1.16 Ah LiFePO4/SiO laminated cell shows negligible voltage and temperature changes during the nail penetration test. The Li concentration in the active material (Si-rich phase) is found to be almost the same as that in the SiO2-rich phase after the test. This high thermal stability and safety may be due to the formed layer from the SiO2 matrix, preventing any side reaction from occurring on the Si surface and isolating the internal current path during the nail penetration.

  10. Novel synthesis of tin oxide/graphene aerogel nanocomposites as anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    A novel method of mechanical exfoliation followed by hydrothermal approach was proposed to synthesize the tin oxide/graphene aerogels (SnO2/GAs) nanocomposites. Homogeneous distribution of SnO2 nanocrystals on GAs was confirmed by SEM, XRD and TEM characterization. It was found that optimized exfoliation of the SnS2 is the key factor to obtain high electrochemical lithiation/delithiation performance of the anodes. The as-prepared SnO2/GA nanocomposites exhibited high reversible capacity (up to 1086.7 mAh g−1 after 100 cycles) and excellent cycling stability. The improved rate capability was also obtained, for instance, the reversible capacity at a current density of 800 mA g−1 is over 447.9 mAh g−1, and then recovered to as high as 784.4 mAh g−1 at a current density of 100 mA g−1. - Highlights: • A novel approach was employed to synthesize the SnO2/GA nanocomposites. • The designed SnO2/GAs exhibited high reversible capacity and excellent cycling stability. • The volume change challenge of SnO2 was markedly alleviated by the GA matrix. • The novel synthesis method can be extended for other materials in lithium ion batteries

  11. Novel synthesis of tin oxide/graphene aerogel nanocomposites as anode materials for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zheyu [College of Material Science and Engineering, Liaoning Technical University, Fuxin 123000 (China); Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Li, Xifei, E-mail: xfli2011@hotmail.com [Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Tai, Limin, E-mail: tailimin@163.com [College of Material Science and Engineering, Liaoning Technical University, Fuxin 123000 (China); Song, Haoze; Zhang, Yiyan; Yan, Bo; Fan, Linlin; Shan, Hui [Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Li, Dejun, E-mail: dli1961@126.com [Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China)

    2015-10-15

    A novel method of mechanical exfoliation followed by hydrothermal approach was proposed to synthesize the tin oxide/graphene aerogels (SnO{sub 2}/GAs) nanocomposites. Homogeneous distribution of SnO{sub 2} nanocrystals on GAs was confirmed by SEM, XRD and TEM characterization. It was found that optimized exfoliation of the SnS{sub 2} is the key factor to obtain high electrochemical lithiation/delithiation performance of the anodes. The as-prepared SnO{sub 2}/GA nanocomposites exhibited high reversible capacity (up to 1086.7 mAh g{sup −1} after 100 cycles) and excellent cycling stability. The improved rate capability was also obtained, for instance, the reversible capacity at a current density of 800 mA g{sup −1} is over 447.9 mAh g{sup −1}, and then recovered to as high as 784.4 mAh g{sup −1} at a current density of 100 mA g{sup −1}. - Highlights: • A novel approach was employed to synthesize the SnO{sub 2}/GA nanocomposites. • The designed SnO{sub 2}/GAs exhibited high reversible capacity and excellent cycling stability. • The volume change challenge of SnO{sub 2} was markedly alleviated by the GA matrix. • The novel synthesis method can be extended for other materials in lithium ion batteries.

  12. Metal dicarboxylates: new anode materials for lithium-ion batteries with good cycling performance.

    Science.gov (United States)

    Fei, Hailong; Liu, Xin; Li, Zhiwei; Feng, Wenjing

    2015-06-01

    A simple and versatile method for the preparation of manganese coordination polymers [Mn(3,5-PDC)·2H2O] (3,5-H2PDC = 3,5-pyridinedicarboxylic acid) and Mn 2,5-furandicarboxylate which goes via a simple hydrothermal route is developed and the coordination polymers are tested as novel high-energy anode materials for lithium-ion batteries for the first time. [Mn(3,5-PDC)·2H2O] shows a high discharge capacity of 583.9 mA h g(-1) for the fourth cycle between a 0.05-3.0 V voltage limit at a discharge current density of 100 mA g(-1). A reversible capacity of 554.0 mA h g(-1) is retained after 240 cycles with a capacity retention of 94.8% while Mn 2,5-furandicarboxylate shows a high discharge capacity of 467.3 mA h g(-1) for the second cycle and a reversible capacity of 436.6 mA h g(-1) is retained after 206 cycles with a capacity retention of 93.4%. PMID:25940917

  13. Protein-releasing conductive anodized alumina membranes for nerve-interface materials.

    Science.gov (United States)

    Altuntas, Sevde; Buyukserin, Fatih; Haider, Ali; Altinok, Buket; Biyikli, Necmi; Aslim, Belma

    2016-10-01

    Nanoporous anodized alumina membranes (AAMs) have numerous biomedical applications spanning from biosensors to controlled drug delivery and implant coatings. Although the use of AAM as an alternative bone implant surface has been successful, its potential as a neural implant coating remains unclear. Here, we introduce conductive and nerve growth factor-releasing AAM substrates that not only provide the native nanoporous morphology for cell adhesion, but also induce neural differentiation. We recently reported the fabrication of such conductive membranes by coating AAMs with a thin C layer. In this study, we investigated the influence of electrical stimulus, surface topography, and chemistry on cell adhesion, neurite extension, and density by using PC 12 pheochromocytoma cells in a custom-made glass microwell setup. The conductive AAMs showed enhanced neurite extension and generation with the electrical stimulus, but cell adhesion on these substrates was poorer compared to the naked AAMs. The latter nanoporous material presents chemical and topographical features for superior neuronal cell adhesion, but, more importantly, when loaded with nerve growth factor, it can provide neurite extension similar to an electrically stimulated CAAM counterpart. PMID:27287158

  14. Hollow Cobalt Selenide Microspheres: Synthesis and Application as Anode Materials for Na-Ion Batteries.

    Science.gov (United States)

    Ko, You Na; Choi, Seung Ho; Kang, Yun Chan

    2016-03-16

    The electrochemical properties of hollow cobalt oxide and cobalt selenide microspheres are studied for the first time as anode materials for Na-ion batteries. Hollow cobalt oxide microspheres prepared by one-pot spray pyrolysis are transformed into hollow cobalt selenide microspheres by a simple selenization process using hydrogen selenide gas. Ultrafine nanocrystals of Co3O4 microspheres are preserved in the cobalt selenide microspheres selenized at 300 °C. The initial discharge capacities for the Co3O4 and cobalt selenide microspheres selenized at 300 and 400 °C are 727, 595, and 586 mA h g(-1), respectively, at a current density of 500 mA g(-1). The discharge capacities after 40 cycles for the same samples are 348, 467, and 251 mA h g(-1), respectively, and their capacity retentions measured from the second cycle onward are 66, 91, and 50%, respectively. The hollow cobalt selenide microspheres have better rate performances than the hollow cobalt oxide microspheres. PMID:26918934

  15. Potential threshold of anode materials for foldable lithium-ion batteries featuring carbon nanotube current collectors

    Science.gov (United States)

    Wang, Qing Hui; Zhong, Sheng Wen; Hu, Jing Wei; Liu, Ting; Zhu, Xian Yan; Chen, Jing; Hong, Yin Yan; Wu, Zi Ping

    2016-04-01

    Flexible carbon nanotube macro-films (CMFs) are perfect current collectors for preparing foldable lithium-ion batteries (LIBs). However, selecting appropriate anodes for electrode is difficult because of the different potentials (vs. Li/Li+) of carbon nanotubes and traditional metallic current collector. This study demonstrated an additional reaction at potential below 0.9 V (vs. Li/Li+) caused by CMF, And Li+ will be constrained, which decreased capacity of anode/CMF electrode. Conversely, results changed when the anode potential exceeded 0.9 V (vs. Li/Li+) because Li+ passed the potential threshold, and the CMF retained its electrochemical inactivity. Consequently, the CMF-based foldable LIBs performed well. The potential threshold mechanism of anode is expected to provide new impetus to both academia and industry for exploring flexible or foldable LIBs.

  16. TiO2 anode materials for lithium-ion batteries with different morphology and additives

    Science.gov (United States)

    Liu, Xiang; Ng, Yip Hang; Leung, Yu Hang; Liu, Fangzhou; Djurišic, Aleksandra B.; Xie, Mao Hai; Chan, Wai Kin

    2014-03-01

    Electrochemical performances of different TiO2 nanostructures, TiO2/CNT composite and TiO2 with titanium isopropoxide (TTIP) treatment anode were investigated. For different TiO2 nanostructures, we investigated vertically aligned TiO2 nanotubes on Ti foil and TiO2 nanotube-powders fabricated by rapid breakdown anodization technique. The morphology of the prepared samples was characterized by scanning probe microscopy (SEM). The electrochemical lithium storage abilities were studied by galvanostatic method. In addition, carbon nanotubes (CNT) additives and solution treatment process of TiO2 anode were investigated, and the results show that the additives and treatment could enhance the cycling performance of the TiO2 anode on lithium ion batteries.

  17. The electrochemical performance and mechanism of cobalt (II) fluoride as anode material for lithium and sodium ion batteries

    International Nuclear Information System (INIS)

    Highlights: •The as-prepared CoF2 shows excellent electrochemical performance as anode material for lithium ion batteries. •The Li insertion/extraction mechanism of CoF2 below 1.2 V was firstly proposed. •The electrochemical performance of CoF2 as anode material in sodium ion batteries was firstly studied. -- Abstract: Cobalt (II) fluoride begins to enter into the horizons of people along with the research upsurge of metal fluorides. It is very significative and theoretically influential to make certain its electrochemical reaction mechanism. In this work, we discover a new and unrevealed reversible interfacial intercalation mechanism reacting below 1.2 V for cobalt (II) fluoride electrode material, which contributes a combined discharge capacity of about 400 mA h g−1 with the formation of SEI film at the initial discharge process. A highly reversible storage capacity of 120 mA h g−1 is observed when the cell is cycled over the voltage of 0.01-1.2 V at 0.2 C, and the low-potential voltage reaction process has a significant impact for the whole electrochemical process. Electrochemical analyses suggest that pure cobalt (II) fluoride shows better electrochemical performance when it is cycled at 3.2-0.01 V compared to the high range (1.0-4.5 V). So, we hold that cobalt (II) fluoride is more suitable to serve as anode material for lithium ion batteries. In addition, we also try to reveal the relevant performance and reaction mechanism, and realize the possibility of cobalt (II) fluoride as anode material for sodium ion batteries

  18. A study about γ-MnOOH nanowires as anode materials for rechargeable Li-ion batteries

    International Nuclear Information System (INIS)

    Highlights: ► Manganite nanowires were tested as the anode materials for Li-ion batteries. ► The OH– ions present in γ-MnOOH do not interfere with the lithium uptake and extraction. ► The capacity of this material stabilizes at about 400 mA h g−1 after 20 cycles. ► The working mechanism for the first discharge may be: γ-MnOOH+3Li++3e-→Mn+Li2O+LiOH. ► The working mechanism for the following cycles may be: Li2O+3/4Mn↔2Li++1/4Mn3O4+2e-. - Abstract: Manganite (γ-MnOOH) nanowires have been synthesized using a hydrothermal method and their electrochemical properties as the anode materials for rechargeable Li-ion batteries have been measured. The results show that the hydroxide ions present in γ-MnOOH do not interfere with the lithium uptake and extraction, making the manganite nanowires able to reversibly react with large amount of Li. The working mechanism of γ-MnOOH as the anode active material for rechargeable Li-ion batteries is examined by TEM and the corresponding SAEDs, and is confirmed to be conversion reactions: during the first discharge, the γ-MnOOH nanowires are reduced into clusters of metallic Mn embedded in an amorphous matrix of Li2O and LiOH; the subsequent cycles are reversible redox reactions between metallic Mn and Mn3O4 nanoparticles. The discharge capacity is 1660 mA h g−1 for the first cycle and can stabilize at about 400 mA h g−1 after 20 cycles, which implies that this material can also be a candidate for the anode electrodes for Li-ion batteries.

  19. Spongelike Nanosized Mn 3 O 4 as a High-Capacity Anode Material for Rechargeable Lithium Batteries

    KAUST Repository

    Gao, Jie

    2011-07-12

    Mn3O4 has been investigated as a high-capacity anode material for rechargeable lithium ion batteries. Spongelike nanosized Mn 3O4 was synthesized by a simple precipitation method and characterized by powder X-ray diffraction, Raman scattering and scanning electron microscopy. Its electrochemical performance, as an anode material, was evaluated by galvanostatic discharge-charge tests. The results indicate that this novel type of nanosized Mn3O4 exhibits a high initial reversible capacity (869 mA h/g) and significantly enhanced first Coulomb efficiency with a stabilized reversible capacity of around 800 mA h/g after over 40 charge/discharge cycles. © 2011 American Chemical Society.

  20. Purification and carbon-film-coating of natural graphite as anode materials for Li-ion batteries

    International Nuclear Information System (INIS)

    A process of modification of natural graphite materials as anode for lithium ion batteries was attempted. The process started with the treatment of natural graphite with concentrated hydrochloric acid and concentrated sulfuric acid in a thermal autoclave, followed by the in situ polymerization of resorcinol-formaldehyde resin to coat the graphite, then heat-treatment. SEM, XRD, Raman and electrochemical charge-discharge analysis showed that the surface defects and impurities on natural graphite were eliminated by purification of the concentrated acids, and carbon-film encapsulation modified the surface structure of the graphite and reduced its BET surface area. The as-obtained natural graphite sample presented an initial charge-discharge coulombic efficiency of 88.4% and a reversible capacity of 355.8 mAh g-1. The proposed process paves a way to prepare a promising anode material with excellent performance with low cost of natural graphite for rechargeable lithium ion batteries

  1. Synthesis and Characterization of Silicon Nanoparticles Inserted into Graphene Sheets as High Performance Anode Material for Lithium Ion Batteries

    OpenAIRE

    Yong Chen; Xuejun Zhang; Yanhong Tian; Xi Zhao

    2014-01-01

    Silicon nanoparticles have been successfully inserted into graphene sheets via a novel method combining freeze-drying and thermal reduction. The structure, electrochemical performance, and cycling stability of this anode material were characterized by SEM, X-ray diffraction (XRD), charge/discharge cycling, and cyclic voltammetry (CV). CV showed that the Si/graphene nanocomposite exhibits remarkably enhanced cycling performance and rate performance compared with bare Si nanoparticles for lithi...

  2. Electrochemical properties of SnO2/carbon composite materials as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: → SnO2/carbon powders with a cauliflower-like particle structure were synthesized. → Post-annealing can improve the electrochemical properties of SnO2/C composite. → The 500 deg. C-annealed SnO2/C shows the best electrochemical performance. → The lithium ion diffusion coefficients of the SnO2/C electrodes were calculated. - Abstract: SnO2/carbon composite anode materials were synthesized from SnCl4.5H2O and sucrose via a hydrothermal route and a post heat-treatment. The synthesized spherical SnO2/carbon powders show a cauliflower-like micro-sized structure. High annealing temperature results in partial reduction of SnO2. Metallic Sn starts to emerge at 500 deg. C. High Sn content in SnO2/carbon composite is favorable for the increase of initial coulombic efficiency but not for the cycling stability. The SnO2/carbon annealed at 500 deg. C exhibits high specific capacity (∼400 mAh g-1), stable cycling performance and good rate capability. The generation of Li2O in the first lithiation process can prevent the aggregation of active Sn, while the carbon component can buffer the big volume change caused by lithiation/delithiation of active Sn. Both of them make contribution to the better cycle stability.

  3. Nano Structure Plays an Important Role in the Present and Future Anode Materials of Li-ion Batteries

    Institute of Scientific and Technical Information of China (English)

    Tsutomu; Takamura

    2007-01-01

    1 ResultsLi-ion batteries are the most promising secondary batteries for IT and EV applications, where it is required to increase the capacity and power capability to a great extent. In responding to the demand we have been studied on the anode materials especially paying attention on the improved graphite active materials and modified silicon. In both cases we realized that the nano-structured design plays an important role. In this paper the examples of nano-size structure working in the actual materi...

  4. The developments of SnO2/graphene nanocomposites as anode materials for high performance lithium ion batteries: A review

    Science.gov (United States)

    Deng, Yuanfu; Fang, Chengcheng; Chen, Guohua

    2016-02-01

    With the increasing energy demands for electronic devices and electrical vehicles, anode materials for lithium ion batteries (LIBs) with high specific capacity, good cyclic and rate performances become one of the focal areas of research. Among the various anode materials, SnO2/graphene nanocomposites have drawn extensive attentions due to their high theoretical specific capacities, low charge potential vs. Li/Li+ and environmental benignity. In this review, the advances, including the synthetic methods and structural optimizations, of the SnO2/graphene nanocomposites as anode materials for LIBs have been reviewed in detail. By providing an in-depth discussion of SnO2/graphene nanocomposites, we aim to demonstrate that the electrochemical performances of SnO2/graphene nanocomposites could be significantly enhanced by rational modifications of morphology and crystal structures, chemical compositions and surface features. Though only focusing on SnO2/graphene-based composites, the concepts and strategies should be referential to other metal oxide/graphene composites.

  5. Kinetics of the electrolytic Fe+2/Fe+3 oxidation on various anode materials

    Directory of Open Access Journals (Sweden)

    Cifuentes, L.

    2003-08-01

    Full Text Available The kinetics of the electrolytic Fe+2/Fe+3 oxidation, relevant to hydro-electrometallurgical processing, have been studied on lead, platinum, ruthenium oxide, iridium oxide and graphite anodes in ferrous sulfate-sulfuric acid solutions. The oxidation rate depends on ferrous sulfate concentration, solution temperature and degree of agitation. Potentiodynamic studies show that: a the highest oxidation rate is obtained on platinum; b lead is unsuitable as anodic material for the said reaction; c the remaining anode materials show a similar and satisfactory performance.

    Se ha estudiado la cinética de la oxidación electrolítica Fe+2/Fe+3 -relevante para el procesamiento hidroelectrometalúrgico- sobre plomo, platino, óxido de rutenio, óxido de iridio y grafito en soluciones de sulfato ferroso en ácido sulfúrico. La velocidad de oxidación depende de la concentración de sulfato ferroso, la temperatura de la solución y el grado de agitación. Estudios potenciodinámicos demuestran que: a las mayores velocidades de oxidación se obtienen sobre platino; b el plomo es inadecuado como material anódico para la reacción mencionada; c los materiales anódicos restantes exhiben un desempeño similar y satisfactorio.

  6. Micro-sized cadmium tungstate as a high-performance anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jingfu; Pan, Jingen; Shao, Lianyi; Shu, Jie; Zhou, Mingjiong; Pan, Jianguo, E-mail: panjianguo@nbu.edu.cn

    2014-11-25

    Highlights: • CdWO{sub 4} was obtained by a facile and effective precipitation reaction route. • The application of CdWO{sub 4} to a lithium-ion battery anode was firstly reported. • The CdWO{sub 4} anode delivered a high initial discharge capacity of 2304.1 mA h g{sup −1}. • Electrochemical reaction mechanism of CdWO{sub 4} with Li was studied by cyclic voltammetry. - Abstract: The application of cadmium tungstate (CdWO{sub 4}) to a lithium-ion battery anode was firstly reported in this paper. It was prepared by a facile precipitation reaction process. The CdWO{sub 4} sample was characterized using X-ray diffraction and scanning electron microscopy. The electrochemical properties of CdWO{sub 4} anode were investigated. The CdWO{sub 4} delivered a high initial discharge capacity of 2042.4 mA h g{sup −1}. The CdWO{sub 4}/C composite showed an improved electrochemical performance with an initial discharge capacity of 2304.1 mA h g{sup −1} and achieved a discharge capacity of 305.1 mA h g{sup −1} after 19 cycles. Electrochemical reaction mechanism of CdWO{sub 4} with Li was also studied by cyclic voltammetry. It is suggested that CdWO{sub 4} can be a promising high-capacity anode material for lithium-ion batteries.

  7. Facile fabrication of CuO nanosheets on Cu substrate as anode materials for electrochemical energy storage

    International Nuclear Information System (INIS)

    Highlights: • In situ synthesis of sheet-like CuO on Cu substrate via a facile one-step route. • CuO nanosheets serve as anode materials for both sodium and lithium ion batteries. • The effects of preparation conditions on electrochemical performance are investigated. • The mechanisms of electrochemical processes are explored. -- Abstract: CuO nanosheets are synthesized on Cu substrate via a one-step corrosion process, which can be formed at room temperature. The reaction time and solution concentration show great effects on the microstructure of products. The obtained CuO nanosheets are systematically evaluated as anode materials for both lithium-ion battery (LIB) and sodium-ion battery (NIB). The CuO electrode undergoes multi-step conversion processes in both LIB and NIB, but their charge/discharge plateaus are quite different. In LIB, the CuO electrode exhibits a remarkable electrochemical performance. However, the CuO anode in NIB shows poor cyclability and rate capability, which is mainly due to the high interface impedance, large volume expansion and slow ion diffusion caused by the larger size of Na+ ion

  8. Nanostructured Black Phosphorus/Ketjenblack-Multiwalled Carbon Nanotubes Composite as High Performance Anode Material for Sodium-Ion Batteries.

    Science.gov (United States)

    Xu, Gui-Liang; Chen, Zonghai; Zhong, Gui-Ming; Liu, Yuzi; Yang, Yong; Ma, Tianyuan; Ren, Yang; Zuo, Xiaobing; Wu, Xue-Hang; Zhang, Xiaoyi; Amine, Khalil

    2016-06-01

    Sodium-ion batteries are promising alternatives to lithium-ion batteries for large-scale applications. However, the low capacity and poor rate capability of existing anodes for sodium-ion batteries are bottlenecks for future developments. Here, we report a high performance nanostructured anode material for sodium-ion batteries that is fabricated by high energy ball milling to form black phosphorus/Ketjenblack-multiwalled carbon nanotubes (BPC) composite. With this strategy, the BPC composite with a high phosphorus content (70 wt %) could deliver a very high initial Coulombic efficiency (>90%) and high specific capacity with excellent cyclability at high rate of charge/discharge (∼1700 mAh g(-1) after 100 cycles at 1.3 A g(-1) based on the mass of P). In situ electrochemical impedance spectroscopy, synchrotron high energy X-ray diffraction, ex situ small/wide-angle X-ray scattering, high resolution transmission electronic microscopy, and nuclear magnetic resonance were further used to unravel its superior sodium storage performance. The scientific findings gained in this work are expected to serve as a guide for future design on high performance anode material for sodium-ion batteries. PMID:27222911

  9. Novel Mg-Doped SrMoO3 Perovskites Designed as Anode Materials for Solid Oxide Fuel Cells

    Directory of Open Access Journals (Sweden)

    Vanessa Cascos

    2016-07-01

    Full Text Available SrMo1−xMxO3−δ (M = Fe and Cr, x = 0.1 and 0.2 oxides have been recently described as excellent anode materials for solid oxide fuel cells at intermediate temperatures (IT-SOFC with LSGM as the electrolyte. In this work, we have improved their properties by doping with aliovalent Mg ions at the B-site of the parent SrMoO3 perovskite. SrMo1−xMgxO3−δ (x = 0.1, 0.2 oxides have been prepared, characterized and tested as anode materials in single solid-oxide fuel cells, yielding output powers near 900 mW/cm−2 at 850 °C using pure H2 as fuel. We have studied its crystal structure with an “in situ” neutron power diffraction (NPD experiment at temperatures as high as 800 °C, emulating the working conditions of an SOFC. Adequately high oxygen deficiencies, observed by NPD, together with elevated disk-shaped anisotropic displacement factors suggest a high ionic conductivity at the working temperatures. Furthermore, thermal expansion measurements, chemical compatibility with the LSGM electrolyte, electronic conductivity and reversibility upon cycling in oxidizing-reducing atmospheres have been carried out to find out the correlation between the excellent performance as an anode and the structural features.

  10. Synthesis of Li2Ti3O7 Anode Materials by Ultrasonic Spray Pyrolysis and Their Electrochemical Properties

    Directory of Open Access Journals (Sweden)

    Takayuki Kodera

    2013-06-01

    Full Text Available Ramsdellite-type lithium titanate (Li2Ti3O7 powders were synthesized by performing ultrasonic spray pyrolysis, and their chemical and physical properties were characterized by performing Scanning Electron Microscope (SEM, powder X-ray Diffraction (XRD, and Inductively Coupled Plasma (ICP analyses. The as-prepared Li2Ti3O7 precursor powders had spherical morphologies with hollow microstructures, but an irregularly shaped morphology was obtained after calcination above 900 °C. The ramsdellite Li2Ti3O7 crystal phase was obtained after the calcination at 1100 °C under an argon/hydrogen atmosphere. The first rechargeable capacity of the Li2Ti3O7 anode material was 168 mAh/g at 0.1 C and 82 mAh/g at 20 C, and the discharge capacity retention ratio was 99% at 1 C after the 500th cycle. The cycle performance of the Li2Ti3O7 anode was also highly stable at 50 °C, demonstrating the superiority of Li2Ti3O7 anode materials reported previously.

  11. Nanoparticle Cookies Derived from Metal-Organic Frameworks: Controlled Synthesis and Application in Anode Materials for Lithium-Ion Batteries.

    Science.gov (United States)

    Wang, Shuhai; Chen, Minqi; Xie, Yanyu; Fan, Yanan; Wang, Dawei; Jiang, Ji-Jun; Li, Yongguang; Grützmacher, Hansjörg; Su, Cheng-Yong

    2016-05-01

    The capacity of anode materials plays a critical role in the performance of lithium-ion batteries. Using the nanocrystals of oxygen-free metal-organic framework ZIF-67 as precursor, a one-step calcination approach toward the controlled synthesis of CoO nanoparticle cookies with excellent anodic performances is developed in this work. The CoO nanoparticle cookies feature highly porous structure composed of small CoO nanoparticles (≈12 nm in diameter) and nitrogen-rich graphitic carbon matrix (≈18 at% in nitrogen content). Benefiting from such unique structure, the CoO nanoparticle cookies are capable of delivering superior specific capacity and cycling stability (1383 mA h g(-1) after 200 runs at 100 mA g(-1) ) over those of CoO and graphite. PMID:26948965

  12. Preparation of Advanced Carbon Anode Materials from Mesocarbon Microbeads for Use in High C-Rate Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Ming-Dar Fang

    2015-06-01

    Full Text Available Mesophase soft carbon (MSC and mesophase graphite (SMG, for use in comparative studies of high C-rate Lithium Ion Battery (LIB anodes, were made by heating mesocarbon microbeads (MCMB at 1300 °C and 3000 °C; respectively. The crystalline structures and morphologies of the MSC, SMG, and commercial hard carbon (HC were investigated by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy. Additionally, their electrochemical properties, when used as anode materials in LIBs, were also investigated. The results show that MSC has a superior charging rate capability compared to SMG and HC. This is attributed to MSC having a more extensive interlayer spacing than SMG, and a greater number of favorably-oriented pathways when compared to HC.

  13. Nano-crystalline FeOOH mixed with SWNT matrix as a superior anode material for lithium batteries

    Institute of Scientific and Technical Information of China (English)

    Mingzhong Zou; Weiwei Wen; Jiaxin Li; Yingbin Lin; Heng Lai; Zhigao Huang

    2014-01-01

    Nano-crystalline FeOOH particles (5∼10 nm) have been uniformly mixed with electric matrix of single-walled carbon nanotubes (SWNTs) for forming FeOOH/SWNT composite via a facile ultrasonication method. Directly using the FeOOH/SWNT composite (containing 15 wt%SWNTs) as anode material for lithium battery enhances kinetics of the Li+ insertion/extraction processes, thereby effectively improving re-versible capacity and cycle performance, which delivers a high reversible capacity of 758 mAh·g-1 under a current density of 400 mA·g-1 even after 180 cycles, being comparable with previous reports in terms of electrochemical performance for FeOOH anode. The good electrochemical performance should be ascribed to the small particle size and nano-crystalline of FeOOH, as well as the good electronic conductivity of SWNT matrix.

  14. Dispersing SnO2 nanocrystals in amorphous carbon as a cyclic durable anode material for lithium ion batteries

    Institute of Scientific and Technical Information of China (English)

    Renzong Hu; Wei Sun; Meiqin Zeng; Min Zhu

    2014-01-01

    We demonstrate a facile route for the massive production of SnO2/carbon nanocomposite used as high-capacity anode materials of next-generation lithium-ion batteries. The nanocomposite had a unique structure of ultrafine SnO2 nanocrystals (∼5 nm, 80 wt%) homogeneously dispersed in amorphous carbon matrix. This structure design can well accommodate the volume change of Li+insertion/desertion in SnO2, and prevent the aggregation of the nanosized active materials during cycling, leading to superior cycle performance with stable reversible capacity of 400 mAh/g at a high current rate of 3.3 A/g.

  15. Pulsed laser deposited Cr2O3 nanostructured thin film on graphene as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: A different approach for the fabrication of an anode material system that comprises pulsed laser-deposited (PLD) Cr2O3 grown on few layer graphene (FLG) by chemical vapor deposition (CVD) was used. The electrochemical performance of Cr2O3 nanostructured thin film was improved by FLG, which make it a promising candidate for future lithium-ion batteries application. - Highlights: • Pulsed laser deposition technique was used to deposit Cr2O3 on few-layer graphene (FLG). • FLG improved the electrochemical performance of Cr2O3 nanostructured thin film. • Good stable cycle of Cr2O3/FLG/Ni electrode make it one of the promise anode materials for future lithium-ion batteries. - Abstract: Pulsed laser deposition technique was used to deposit Cr2O3 nanostructured thin film on a chemical vapor deposited few-layer graphene (FLG) on nickel (Ni) substrate for application as anode material for lithium-ion batteries. The experimental results show that graphene can effectively enhance the electrochemical property of Cr2O3. For Cr2O3 thin film deposited on Ni (Cr2O3/Ni), a discharge capacity of 747.8 mA h g−1 can be delivered during the first lithiation process. After growing Cr2O3 thin film on FLG/Ni, the initial discharge capacity of Cr2O3/FLG/Ni was improved to 1234.5 mA h g−1. The reversible lithium storage capacity of the as-grown material is 692.2 mA h g−1 after 100 cycles, which is much higher than that of Cr2O3/Ni (111.3 mA h g−1). This study reveals the differences between the two material systems and emphasizes the role of the graphene layers in improving the electrochemical stability of the Cr2O3 nanostructured thin film

  16. Nb-doped rutile TiO₂: a potential anode material for Na-ion battery.

    Science.gov (United States)

    Usui, Hiroyuki; Yoshioka, Sho; Wasada, Kuniaki; Shimizu, Masahiro; Sakaguchi, Hiroki

    2015-04-01

    The electrochemical properties of the rutile-type TiO2 and Nb-doped TiO2 were investigated for the first time as Na-ion battery anodes. Ti(1-x)Nb(x)O2 thick-film electrodes without a binder and a conductive additive were prepared using a sol-gel method followed by a gas-deposition method. The TiO2 electrode showed reversible reactions of Na insertion/extraction accompanied by expansion/contraction of the TiO2 lattice. Among the Ti(1-x)Nb(x)O2 electrodes with x = 0-0.18, the Ti(0.94)Nb(0.06)O2 electrode exhibited the best cycling performance, with a reversible capacity of 160 mA h g(-1) at the 50th cycle. As the Li-ion battery anode, this electrode also attained an excellent rate capability, with a capacity of 120 mA h g(-1) even at the high current density of 16.75 A g(-1) (50C). The improvements in the performances are attributed to a 3 orders of magnitude higher electronic conductivity of Ti(0.94)Nb(0.06)O2 compared to that of TiO2. This offers the possibility of Nb-doped rutile TiO2 as a Na-ion battery anode as well as a Li-ion battery anode. PMID:25757057

  17. Morphology-controlled graphene nanosheets as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Graphene nanosheets was manufactured using a simple modified version of a previously improved Hummers method. • The wrinkle-free graphene was easily manufactured from prepared graphene by post-process treatment. • Morphology-controlled graphene nanosheets showed excellent discharge performance. • Morphology-controlled graphene has the potential to be easily applied to graphene-wrapped composite. - Abstract: Morphology-controlled graphene nanosheets can be easily synthesized as anode material for application in high-capacity lithium-ion batteries. A modified version of an improved method for higher degree of oxidation of graphite oxide (GO) has been developed and characterized. X-ray diffraction analysis shows that GO prepared using this method has a higher degree of oxidation than that of using the improved method. The interlayer d-spacing increases from 0.87 nm (using the improved method) to 0.92 nm (using the modified-improved method). Also, it is confirmed by XPS analysis that the O/C ratio in GO increases from 2.51 (improved method) to 8.27 (modified-improved method). It is hypothesized that GO, which has a higher degree of oxidation, is more reducible to graphene. The more reduced graphene has a larger amount of free π-bonds and fewer layers, and it can be easily altered to morphology-controlled graphene. Graphene nanosheets prepared using the modified-improved method exhibits discharge capacities of 1079 mAh g−1 (at a constant current of 40 mA g−1) and 1002 mAh g−1 after 50 cycles. The capacity retention of the synthesized graphene nanosheets is 1070 mAh g−1 at a current of 40 mA g−1 after the rate capability test, and their rate capability is 463 mAh g−1 at a current of 400 mA g−1. The morphology-controlled graphene nanosheets prepared by the modified-improved method shows better discharge performance compared to graphene prepared by the improved method

  18. Fabrication of electrospun ZnMn2O4 nanofibers as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • ZnMn2O4 nanofibers were successfully synthesized by a facile electrospinning and calcination method for lithium-ion batteries. • The as-prepared ZnMn2O4 nanofibers, containing PVP and PAN with ratio of 1:9, exhibited a high initial discharge capacity of 1274 mAh g−1, and the stabilized capacity was as high as 603 mAh g−1 after 60 cycles at a current density of 50 mA g−1. • The as-prepared ZnMn2O4 anode material showed good lithium storage performances and excellent rate capability and can be a promising electrode material for lithium-ion batteries in the future. - Abstract: In this paper, ZnMn2O4 nanofibers were synthesized by a facile electrospinning and calcination method. Electrochemical properties of the nanofiber anode material for lithium-ion batteries were investigated. The as-prepared ZnMn2O4 nanofibers, containing PVP and PAN with ratio of 1:9, exhibited a high initial discharge capacity of 1274 mAh g−1, and the stabilized capacity was as high as 603 mAh g−1 after 60 cycles at a current density of 50 mA g−1. Besides the high specific capacity and good cyclability, the electrode also showed good rate capability. Even at 2000 mA g−1, the electrode could deliver a capacity of as high as 352 mAh g−1. The results suggest a promising application of the electrospun ZnMn2O4 nanofibers as anode material for lithium-ion batteries

  19. Synthetic, structural, and electrochemical study of monoclinic Na4Ti5O12 as sodium-ion battery anode material

    International Nuclear Information System (INIS)

    Since lithium-ion batteries were commercialized in 1991, they have dominated the portable electronics market. In 2014, over one-fourth of the world’s mined lithium was devoted to lithiumion battery applications. Increased future demand will be driven by the electric/hybrid vehicle market and load leveling solutions for renewable energy sources. Therefore, the development of new, low-cost alternatives to lithium-ion batteries with comparable electrochemical properties is highly desirable. Sodium is the most obvious choice, as an inexpensive, abundant, and easily extractable element. As well as the decreased cost in starting material, sodium-ion batteries can use aluminum as the current collector for the anode because, unlike lithium, sodium does not alloy with aluminum metal. Aluminum offers both a less-expensive and lighter alternative to the copper usually used in lithium-ion batteries. However, challenges still remain in developing sodium intercalation materials capable of achieving a high reversible capacity and energy density. In particular, because of the inability of Na ions to intercalate with graphite, anode materials must be significantly improved. We have investigated the monoclinic phase of Na4Ti5O12 (M-Na4Ti5O12) as a potential sodium-ion battery anode material. In contrast to the previously investigated trigonal phase (T-Na4Ti5O12), MNa4Ti5O12 has continuous two-dimensional (2D) channels with partially occupied Na sites, providing broader pathways and more space for the intercalation of excess sodium. Neutron powder diffraction reveals the preferred sites and occupancies of the excess sodium as well as the sodium ion conduction pathway. Electrochemical measurements show that it exhibits a comparable or higher reversible capacity than T-Na4Ti5O12. In situ synchrotron X-ray diffraction under electrochemical cycling shows that the crystal lattice undergoes strongly anisotropic volume changes during cycling.

  20. CoNiO nanowire arrays as a high-performance anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • CoNiO/TiO2NTs was synthesized by a facile hydrothermal method. • The addition of Ni to CoO could improve its conductivity. • CoNiO/TiO2NTs nanocomposite material is a 3D structure. • It delivers a high areal capacity when used as lithium-ion battery anode material. -- Abstract: CoNiO nanowire arrays loaded on TiO2 nanotubes (CoNiO/TiO2NTs) are synthesized by a hydrothermal method and used firstly as an anode material for lithium-ion batteries. The morphology, structure and composition of the composite are characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The EDS patterns display the atomic ratio of Co to Ni is 0.41:0.59 with accuracy of more than 99%. SEM images show that the diameters of these nanowires range from 10 to 40 nm and the average length approximately 1 μm. Electrochemical characterizations are performed in a three-electrode system to determine the capacity, cyclic stability and to investigate the reaction mechanism. As an anode material for lithium-ion batteries, the CoNiO/TiO2NTs nanocomposite delivers a high areal capacity of 362 μAh cm−2 (1097 mAh g−1, 0.33 mg cm−2) after 40 discharge/charge cycles at a current density of 0.2 mA cm−2 (about 606 mA g−1). EIS results show that addition of Ni to the CoO could increase the conductivity of the composite significantly and improve the kinetic behavior during discharge–charge process. The present finding provides a kind of nanostructure fabrication that might be applied in supercapacitor and solar cells, etc

  1. Employment of Chitosan–linked Iron Oxides as Mesoporous Anode Materials for Improved Lithium–ion Batteries

    International Nuclear Information System (INIS)

    This study investigates the concentration effect of chitosan on the formation of iron oxide composites and their electrochemical performance as anode materials in Li–ion batteries. The molecular bridging effect of chitosan chains induces the clustered aggregation of citrate–capped Fe3O4 (C–Fe3O4) through the electrostatic interactions between carboxylate groups of C–Fe3O4 and amine groups of chitosan. The thermal calcination of chitosan–linked Fe3O4 leads to carbon–coated Fe2O3 (Fe2O3@carbon) with the mesopore range of porosity (20–30 nm). The mesoporous Fe2O3@carbon exhibits an improved electrochemical performance as anode materials in Li–ion batteries. The capacity retention of Fe2O3@carbon is twice that of bare Fe2O3 after the 50th cycle at 0.1 C. During the charge–discharge process, the Fe2O3@carbon (3 ml of chitosan) exhibits the highest retention capacity among as–prepared samples, whereas Fe2O3@carbon (1 ml of chitosan) exhibits the lowest retention capacity owing to the weakly cross–linked iron oxides. The improved performance of Fe2O3@carbon as anode materials is mainly attributed to the optimal cross–linking effect and structural integrity of mesoporous composite which is beneficial for the effective transport of electrolytes and/or Li–ons, suggesting a useful guideline for preparing porous electrode materials using metal oxide particles

  2. Effect of anodization and alkali-heat treatment on the bioactivity of titanium implant material (an in vitro study)

    Science.gov (United States)

    Abdelrahim, Ramy A.; Badr, Nadia A.; Baroudi, Kusai

    2016-01-01

    Objective: This study was aimed to assess the effect of anodized and alkali-heat surface treatment on the bioactivity of titanium alloy (Ti-6Al-4V) after immersion in Hank's solution for 7 days. Materials and Methods: Fifteen titanium alloy samples were used in this study. The samples were divided into three groups (five for each), five samples were anodized in 1M H3PO4 at constant voltage value of 20 v and another five samples were alkali-treated in 5 M NaOH solution for 25 min at temperature 60°C followed by heat treatment at 600°C for 1 h. All samples were then immersed in Hank's solution for 7 days to assess the effect of surface modifications on the bioactivity of titanium alloy. The different treated surfaces and control one were characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier transformation infra-red spectroscopy. Statistical analysis was performed with PASW Statistics 18.0® (Predictive Analytics Software). Results: Anodization of Ti-alloy samples (Group B) led to the formation of bioactive titanium oxide anatase phase and PO43− group on the surface. The alkali-heat treatment of titanium alloy samples (Group C) leads to the formation of bioactive titania hydrogel and supplied sodium ions. The reaction between the Ti sample and NaOH alkaline solution resulted in the formation of a layer of amorphous sodium titania on the Ti surface, and this layer can induce apatite deposition. Conclusions: The surface roughness and surface chemistry had an excellent ability to induce bioactivity of titanium alloy. The anodization in H3PO4 produced anatase titanium oxide on the surface with phosphate originated from electrolytes changed the surface topography and allowed formation of calcium-phosphate. PMID:27382532

  3. Electrochemical Impedance Spectroscopy Illuminating Performance Evolution of Porous Core–Shell Structured Nickel/Nickel Oxide Anode Materials

    International Nuclear Information System (INIS)

    Highlights: • The electrochemical reaction kinetics of the Ni/NiO anode was studied for the first time. • Charge transfer resistance is main contribution to total resistance during discharge process. • The slow growth of the SEI film is responsible for the capacity fading upon cycling. • Some promising strategies to optimize NiO anode performance were summarized. - Abstract: The electrochemical reaction kinetics of the porous core–shell structured Ni/NiO anode for Li ion battery application is systematically investigated by monitoring the electrochemical impedance evolution for the first time. The electrochemical impedance under prescribed condition is measured by using impedance spectroscopy in equilibrium conditions at various depths of discharge (DOD) during charge–discharge cycles. The Nyquist plots of the binder-free porous Ni/NiO electrode are interpreted with a selective equivalent circuit composed of solution resistance, solid electrolyte interphase (SEI) film, charge transfer and solid state diffusion. The impedance analysis shows that the change of charge transfer resistance is the main contribution to the total resistance change during discharge, and the surface configuration of the obtained electrode may experience significant change during the first two cycles. Meanwhile, the increase of internal resistance reduced the utilization efficiency of the active material may be another convincing factor to increase the irreversible capacity. In addition, the impedance evolution of the as-prepared electrode during charge–discharge cycles reveals that the slow growth of the SEI film is responsible for the capacity fading after long term cycling. As a result, several strategies are summarized to optimize the electrochemical performances of transition metal oxide anodes for lithium ion batteries

  4. LiVP2O7/C: A New Insertion Anode Material for High-Rate Lithium-Ion Battery Applications.

    Science.gov (United States)

    Mani, Vellaisamy; Kalaiselvi, Nallathamby

    2016-04-18

    LiVP2O7/C, popularly known so far as an environmentally compatible and economically viable lithium battery cathode material, was exploited for the first time as an anode through the current study. LiVP2O7/C was synthesized by adopting oxalyl dihydrazide assisted solution combustion method and explored as an anode material in rechargeable lithium cell assembly. Notably, an initial capacity of 600 mAh g(-1) was exhibited by LiVP2O7/C anode, at the rate of 0.5 C along with an excellent Coulombic efficiency of 99% up to 150 cycles. The title anode demonstrates its suitability for high capacity and high rate applications by way of exhibiting appreciable capacity values of 200, 150, 120, and 110 mAh g(-1), under the influence of 2, 4, 6, and 8 C rates, respectively. Further, LiVP2O7/C anode, when subjected to a high current 10 C rate, exhibits an acceptable capacity of 107 mAh g(-1) up to 500 cycles, which is closer to its theoretical capacity value of 117 mAh g(-1). The study demonstrates the possibility of exploiting LiVP2O7/C as yet another potential anode and thereby opens a newer avenue to explore wide variety of LiMP2O7/C composites for their probable anode behavior in rechargeable lithium batteries. PMID:27065103

  5. A phosphorene-graphene hybrid material as a high-capacity anode for sodium-ion batteries

    Science.gov (United States)

    Sun, Jie; Lee, Hyun-Wook; Pasta, Mauro; Yuan, Hongtao; Zheng, Guangyuan; Sun, Yongming; Li, Yuzhang; Cui, Yi

    2015-11-01

    Sodium-ion batteries have recently attracted significant attention as an alternative to lithium-ion batteries because sodium sources do not present the geopolitical issues that lithium sources might. Although recent reports on cathode materials for sodium-ion batteries have demonstrated performances comparable to their lithium-ion counterparts, the major scientific challenge for a competitive sodium-ion battery technology is to develop viable anode materials. Here we show that a hybrid material made out of a few phosphorene layers sandwiched between graphene layers shows a specific capacity of 2,440 mA h g-1 (calculated using the mass of phosphorus only) at a current density of 0.05 A g-1 and an 83% capacity retention after 100 cycles while operating between 0 and 1.5 V. Using in situ transmission electron microscopy and ex situ X-ray diffraction techniques, we explain the large capacity of our anode through a dual mechanism of intercalation of sodium ions along the x axis of the phosphorene layers followed by the formation of a Na3P alloy. The presence of graphene layers in the hybrid material works as a mechanical backbone and an electrical highway, ensuring that a suitable elastic buffer space accommodates the anisotropic expansion of phosphorene layers along the y and z axial directions for stable cycling operation.

  6. Synthesis of nano structured particles for Li-ion cathodic and anodic materials obtained by spray pyrolysis

    International Nuclear Information System (INIS)

    The development of the nano technology has contributed to improve the electrochemical properties in rechargeable batteries. The Spray Pyrolysis method allows to obtain nano structured materials with spherical morphology, narrow particle size distribution and compositional homogeneity. Nano structured particles have been prepared in this work to be used as anodic and cathodic materials in lithium-ion batteries. Among the cathodic materials, the Na-Si-Con (Li3Fe2(PO4)3) structure and the olivine (LiFePO4) phases have been synthesised. The Na-Si-Con iron phosphate favours the accommodation of the ion host, the diffusion and thermal stability. The olivine structure has an open three-dimensional network, favourable for hosting Lithium ions. The characterization by X ray diffraction, electron microscopy (scanning and transmission) and electron diffraction have allowed to identify a mix of crystalline phases of LiFePO4 (Olivine) and Li3Fe2(PO4)3 (Na-Si-Con). Thermal treatments produce porous particles. The tryphilite phase (olivine) appears after a thermal treatment at 800 degree centigrade/12h. Electrochemical results confirm the presence of the Na-Si-Con and olivine phases. Among the materials for being used as anode, the titanium oxides have been classified as good candidates as lithium ion host. The synthesis results in different experimental conditions for obtaining spherical and nano structured titanium oxide particles are presented. (Author)

  7. Co3O4/C nanocapsules with onion-like carbon shells as anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: Co3O4 nanocapsules with the onion-like carbon shells were synthesized. As anode materials for lithium ion battery, the Co3O4 nanocapsules deliver an initial discharge capacity of 1467.6 mAh g−1 at 0.5 C and maintain a high reversible capacity of 1026.9 mAh g−1 after 50 cycles. -- Highlights: • Co3O4 nanocapsules with onion-like carbon shell have been synthesized. • Co3O4 nanocapsules deliver an initial discharge capacity of 1467.6 mAh g−1 at 0.5 C. • Co3O4 nanocapsules maintain a reversible capacity of 1026.9 mAh g−1 after 50 cycles. • Onion-like carbon shells can improve the electrochemical performance of Co3O4. -- Abstract: The synthesis and characterization of core/shell-type Co3O4/C nanocapsules for application as anode material in lithium ion batteries are reported in this paper. The synthesis process involves the preparation of Co/C nanocapsules using a modified arc-discharge method and the annealing of the Co/C nanocapsules at 300 °C for 2 h in air. The as-synthesized products show a spherical shape and a core/shell-type structure in which a Co3O4 nanoparticle core of diameter 10–30 nm is encapsulated by an onion-like carbon shell of thickness approximately 1 nm. The Co/C nanocapsules can be stable below 130 °C, and be oxidized above 205 °C in air. The Co3O4/C nanocapsules deliver an initial discharge capacity of 1467.6 mAh g−1 at 0.5 C and maintain a high reversible capacity of 1026.9 mAh g−1 after 50 charge–discharge cycles, much higher than the Co3O4 nanoparticles (471.5 mAh g−1). A postmortem analysis of the Co3O4 and Co3O4/C anodes subjected to prolonged cycling reveals the existence of a lower degree of surface cracking and particle breakage in the Co3O4/C anode than the Co3O4 anode. The improved electrochemical performance and structural stability in the Co3O4/C nanocapsules are attributed to the enhanced electrical conductivity and structural buffering provided by the onion-like carbon shell

  8. Electrical Conductivity and Corrosion Resistance of ZnFe2O4-Based Materials Used as Inert Anode for Aluminum Electrolysis

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    ZnFe2O4 and ZnFe2O4-based materials were tested to obtain the electrical conductivity and corrosion resistance in melting bath for aluminum electrolysis. The results proved that adequate additives, such as Ni2O3 CuO,Cu, ZnO and CeO2 would increase the electrical conductivity, and the ZnFe2O4-based anodes with these additives were of good corrosion resistance. The current density on anode, the mole ratio of NaF/AlF3 (MR) and the content of alumina in the bath effect the anode corrosion rate in different way.

  9. Lignin-based active anode materials synthesized from low-cost renewable resources

    Science.gov (United States)

    Rios, Orlando; Tenhaeff, Wyatt Evan; Daniel, Claus; Dudney, Nancy Johnston; Johs, Alexander; Nunnery, Grady Alexander; Baker, Frederick Stanley

    2016-06-07

    A method of making an anode includes the steps of providing fibers from a carbonaceous precursor, the carbon fibers having a glass transition temperature T.sub.g. In one aspect the carbonaceous precursor is lignin. The carbonaceous fibers are placed into a layered fiber mat. The fiber mat is fused by heating the fiber mat in the presence of oxygen to above the T.sub.g but no more than 20% above the T.sub.g to fuse fibers together at fiber to fiber contact points and without melting the bulk fiber mat to create a fused fiber mat through oxidative stabilization. The fused fiber mat is carbonized by heating the fused fiber mat to at least 650.degree. C. under an inert atmosphere to create a carbonized fused fiber mat. A battery anode formed from carbonaceous precursor fibers is also disclosed.

  10. MnO-carbon hybrid nanofiber composites as superior anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    MnO-carbon hybrid nanofiber composites are fabricated by electrospinning polyimide/manganese acetylacetonate precursor and a subsequent carbonization process. The composition, phase structure and morphology of the composites are characterized by scanning and transmission electron microscopy, X-ray diffraction and thermogravimetric analysis. The results indicate that the composites exhibit good nanofibrous morphology with MnO nanoparticles uniformly encapsulated by carbon nanofibers. The hybrid nanofiber composites are used directly as freestanding anodes for lithium-ion batteries to evaluate their electrochemical properties. It is found that the optimized MnO-carbon nanofiber composite can deliver a high reversible capacity of 663 mAh g−1, along with excellent cycling stability and good rate capability. The superior performance enables the composites to be promising candidates as an anode alternative for high-performance lithium-ion batteries

  11. Tracing locations of new coating material during spark anodizing of titanium

    OpenAIRE

    Matykina, Endzhe; Monfort, Frederic Louis; Berkani, Ahmed; Skeldon, Peter; Thompson, George; Chapon, Patrick

    2005-01-01

    Abstract The growth of anodic coatings on titanium, under sparking conditions, is investigated in tracer experiments, using alkaline silicate and phosphate electrolytes. Coatings are formed sequentially in each electrolyte, with phosphorus and silicon located by energy-dispersive X-ray analysis and glow discharge optical emission spectroscopy. The coatings, containing anatase, rutile and amorphous oxide, with incorporated phosphorus and silicon species, are shown to grow by discret...

  12. Marine microbial fuel cell : use of stainless steel electrodes as anode and cathode materials

    OpenAIRE

    Dumas, Claire; Mollica, Alfonso; Féron, Damien; Basséguy, Régine; Etcheverry, Luc; Bergel, Alain

    2007-01-01

    Numerous biocorrosion studies have stated that biofilms formed in aerobic seawater induce an efficient catalysis of the oxygen reduction on stainless steels. This property was implemented here for the first time in a marine microbial fuel cell (MFC). A prototype was designed with a stainless steel anode embedded in marine sediments coupled to a stainless steel cathode in the overlying seawater. Recording current/potential curves during the progress of the experiment confirmed that the cath...

  13. Graphdiyne as a high-capacity lithium ion battery anode material

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Byungryul; Koo, Jahyun; Park, Minwoo; Kwon, Yongkyung; Lee, Hoonkyung, E-mail: hkiee3@konkuk.ac.kr [School of Physics, Konkuk University, Seoul 143-701 (Korea, Republic of); Lee, Hosik [School of Mechanical and Advanced Materials Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of); Nam, Jaewook [School of Chemical Engineering, Sungkyunkwan University, Suwon 300 (Korea, Republic of)

    2013-12-23

    Using the first-principles calculations, we explored the feasibility of using graphdiyne, a 2D layer of sp and sp{sup 2} hybrid carbon networks, as lithium ion battery anodes. We found that the composite of the Li-intercalated multilayer α-graphdiyne was C{sub 6}Li{sub 7.31} and that the calculated voltage was suitable for the anode. The practical specific/volumetric capacities can reach up to 2719 mAh g{sup −1}/2032 mAh cm{sup −3}, much greater than the values of ∼372 mAh g{sup −1}/∼818 mAh cm{sup −3}, ∼1117 mAh g{sup −1}/∼1589 mAh cm{sup −3}, and ∼744 mAh g{sup −1} for graphite, graphynes, and γ-graphdiyne, respectively. Our calculations suggest that multilayer α-graphdiyne can serve as a promising high-capacity lithium ion battery anode.

  14. Structural and electrochemical properties of SnO nanoflowers as an anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: -- Novel self-assembled highly hierarchical SnO nanoflowers with acute edge petals have been successfully synthesized by a template-free hydrothermal growth method using SnCl2·2H2O and KOH as precursors. Field emission scanning electron microscopy results show that the flower-like SnO architectureis in the range 4–7 μm. Furthermore, Raman modes at A1g = 212 and B1g = 114 cm−1 further testify to the existence of nanotetragonal phase SnO. The electrochemical results suggest that synthesized SnO nanoflowers are a promising anode material for lithium ion batteries.

  15. Electrochemical characteristics of ternary and quadruple lithium silicon nitrides as anode material for lithium ion batteries: the influence of precursors

    Institute of Scientific and Technical Information of China (English)

    WEN Zhongsheng; TIAN Feng; SUN Juncai; JI Shijun; XIE Jingying

    2008-01-01

    Ternary and quadruple lithium silicon nitride anode materials for lithium ion batteries with different precursors were prepared by the simple process of high-energy ball milling.High capacity and excellent cyclability were obtained.The influence of precursor introduction on the electrochemical performance of products was investigated.This research reveals that the electrochemical performance of lithium silicon hiaide can be enhanced significantly by doping O.The cyclability of quadruple lithium silicon nitride can be optimized remarkably by controlling the introduction quantity of the precursors.It is possible for the composite to be used as a capacity compensator within a wide voltage cut-off window.

  16. Prepartion and electrochemical performance of a cerium oxide-graphene nanocomposite as the anode material of a lithium ion battery

    International Nuclear Information System (INIS)

    A nanocomposite of CeO2-graphene was prepared by a simple hydrothermal method and its electrochemical properties were investigated as a possible anode material for lithium ion batteries. Morphological characterization revealed that quasi-spherical CeO2 particles with a size of ∼100 nm were dispersed randomly on the graphene matrix. The nanocomposite shows a greater capacity for reversal and a better performance rate than a bare CeO2 electrode. The better electrochemical performance could be attributed to the unique structure of the nanocomposite, which combines the conductive graphene network with dispersed CeO2 particles.

  17. Structure and electrochemical performance of Fe3O4/graphene nanocomposite as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: → Fe3O4 nanoparticles dispersed homogeneously on graphene nanosheets were synthesized by hydrothermal route. → The Fe3O4/graphene nanocomposite as the anode material for lithium ion batteries showed a high reversible specific capacity of 771 mAh g-1 during up to 50 cycles and good rate capability. → The simple and low-cost method provides a potential approach for fabricating other graphene based materials. - Abstract: Using hydrothermal method, Fe3O4/graphene nanocomposite is prepared by synthesizing Fe3O4 particles in graphene. The synthesized Fe3O4 is nano-sized sphere particles (100-200 nm) and uniformly distributed on the planes of graphene. Fe3O4/graphene nanocomposite as anode material for lithium ion batteries shows high reversible specific capacity of 771 mAh g-1 at 50th cycle and good rate capability. The excellent electrochemical performance of the nanocomposite can be attributed to the high surface area and good electronic conductivity of graphene. Due to the high surface area, graphene can prevent Fe3O4 nanoparticles from aggregating and provide enough space to buffer the volume change during the Li insertion/extraction processes in Fe3O4 nanoparticles.

  18. A novel Si/Sn composite with entangled ribbon structure as anode materials for lithium ion battery

    Science.gov (United States)

    Wu, Jinbo; Zhu, Zhengwang; Zhang, Hongwei; Fu, Huameng; Li, Hong; Wang, Aimin; Zhang, Haifeng

    2016-07-01

    A novel Si/Sn composite anode material with unique ribbon structure was synthesized by Mechanical Milling (MM) and the structural transformation was studied in the present work. The microstructure characterization shows that Si/Sn composite with idealized entangled ribbon structured can be obtained by milling the mixture of the starting materials, Si and Sn for 20 h. According to the calculated results based on the XRD data, the as-milled 20 h sample has the smallest avergae crystalline size. It is supposed that the flexible ribbon structure allows for accommodation of intrinsic damage, which significantly improves the fracture toughness of the composite. The charge and discharge tests of the as-milled 20 h sample have been performed with reference to Li+/Li at a current density of 400 mA g‑1 in the voltage from 1.5 to 0.03 V (vs Li/Li+) and the result shows that the initial capacity is ∼1400 mA h g‑1, with a retention of ∼1100 mA h g‑1 reversible capacity after 50 cycles, which is possible serving as the promising anode material for the lithium ion battery application.

  19. Silicon as a potential anode material for Li-ion batteries: where size, geometry and structure matter.

    Science.gov (United States)

    Ashuri, Maziar; He, Qianran; Shaw, Leon L

    2016-01-01

    Silicon has attracted huge attention in the last decade because it has a theoretical capacity ∼10 times that of graphite. However, the practical application of Si is hindered by three major challenges: large volume expansion during cycling (∼300%), low electrical conductivity, and instability of the SEI layer caused by repeated volume changes of the Si material. Significant research efforts have been devoted to addressing these challenges, and significant breakthroughs have been made particularly in the last two years (2014 and 2015). In this review, we have focused on the principles of Si material design, novel synthesis methods to achieve such structural designs, and the synthesis-structure-performance relationships to enhance the properties of Si anodes. To provide a systematic overview of the Si material design strategies, we have grouped the design strategies into several categories: (i) particle-based structures (containing nanoparticles, solid core-shell structures, hollow core-shell structures, and yolk-shell structures), (ii) porous Si designs, (iii) nanowires, nanotubes and nanofibers, (iv) Si-based composites, and (v) unusual designs. Finally, our personal perspectives on outlook are offered with an aim to stimulate further discussion and ideas on the rational design of durable and high performance Si anodes for the next generation Li-ion batteries in the near future. PMID:26612324

  20. High-Performance Si/SiOx Nanosphere Anode Material by Multipurpose Interfacial Engineering with Black TiO2-x.

    Science.gov (United States)

    Bae, Juhye; Kim, Dae Sik; Yoo, Hyundong; Park, Eunjun; Lim, Young-Geun; Park, Min-Sik; Kim, Young-Jun; Kim, Hansu

    2016-02-24

    Silicon oxides (SiOx) have attracted recent attention for their great potential as promising anode materials for lithium ion batteries as a result of their high energy density and excellent cycle performance. Despite these advantages, the commercial use of these materials is still impeded by low initial Coulombic efficiency and high production cost associated with a complicated synthesis process. Here, we demonstrate that Si/SiOx nanosphere anode materials show much improved performance enabled by electroconductive black TiO2-x coating in terms of reversible capacity, Coulombic efficiency, and thermal reliability. The resulting anode material exhibits a high reversible capacity of 1200 mAh g(-1) with an excellent cycle performance of up to 100 cycles. The introduction of a TiO2-x layer induces further reduction of the Si species in the SiOx matrix phase, thereby increasing the reversible capacity and initial Coulombic efficiency. Besides the improved electrochemical performance, the TiO2-x coating layer plays a key role in improving the thermal reliability of the Si/SiOx nanosphere anode material at the same time. We believe that this multipurpose interfacial engineering approach provides another route toward high-performance Si-based anode materials on a commercial scale. PMID:26820496

  1. Ultrahigh capacity anode material for lithium ion battery based on rod gold nanoparticles decorated reduced graphene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Atar, Necip, E-mail: necipatar@gmail.com [Department of Chemical Engineering, Pamukkale University, Denizli (Turkey); Eren, Tanju [Department of Chemical Engineering, Pamukkale University, Denizli (Turkey); Yola, Mehmet Lütfi [Department of Metallurgical and Materials Engineering, Sinop University, Sinop (Turkey)

    2015-09-01

    In this study, we report the synthesis of rod shaped gold nanoparticles/2-aminoethanethiol functionalized reduced graphene oxide composite (rdAuNPs/AETrGO) and its application as an anode material for lithium-ion batteries. The structure of the rdAuNPs/AETrGO composite was characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction. The electrochemical performance was investigated at different current rates by using a coin-type cell. It was found that the rod shaped gold nanoparticles were highly dispersed on the reduced graphene oxide sheets. Moreover, the rdAuNPs/AETrGO composite showed a high specific gravimetric capacity of about 1320 mAh g{sup −1} and a long-term cycle stability. - Highlights: • We prepared rod shaped gold nanoparticles functionalized reduced graphene oxide. • The nanocomposite was used as an anode material for lithium-ion batteries. • The nanocomposite showed a high specific gravimetric capacity of about 1320 mAh g{sup −1}. • The nanocomposite exhibited a long-term cycle stability.

  2. Synthesis And Electrochemical Characteristics Of Mechanically Alloyed Anode Materials SnS2 For Li/SnS2 Cells

    Directory of Open Access Journals (Sweden)

    Hong J.H.

    2015-06-01

    Full Text Available With the increasing demand for efficient and economic energy storage, tin disulfide (SnS2, as one of the most attractive anode candidates for the next generation high-energy rechargeable Li-ion battery, have been paid more and more attention because of its high theoretical energy density and cost effectiveness. In this study, a new, simple and effective process, mechanical alloying (MA, has been developed for preparing fine anode material tin disulfides, in which ammonium chloride (AC, referred to as process control agents (PCAs, were used to prevent excessive cold-welding and accelerate the synthesis rates to some extent. Meanwhile, in order to decrease the mean size of SnS2 powder particles and improve the contact areas between the active materials, wet milling process was also conducted with normal hexane (NH as a solvent PCA. The prepared powders were both characterized by X-ray diffraction, Field emission-scanning electron microscopeand particle size analyzer. Finally, electrochemical measurements for Li/SnS2 cells were takenat room temperature, using a two-electrode cell assembled in an argon-filled glove box and the electrolyte of 1M LiPF6 in a mixture of ethylene carbonate(EC/dimethylcarbonate (DMC/ethylene methyl carbonate (EMC (volume ratio of 1:1:1.

  3. Fe1.5Ti0.5O3 nanoparticles as an anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Iron titanium oxide (Fe1.5Ti0.5O3) nanoparticles with the diameter of about 150 nm were prepared by hydrothermal process and further heat treatment at 300 °C for 2 h. The morphology, structure and electrochemical performance of Fe1.5Ti0.5O3 nanoparticles as anode material for lithium-ion batteries were investigated by scanning electron microscopy, X-ray diffraction and a variety of electrochemical testing techniques. It was found that, compared with TiO2 and Fe2O3, the iron titanium oxide electrode exhibited higher specific capacity of 734.9 mAh g−1 after 50 cycles at the current density of 50 mA g−1, good cycle stability and high-rate performance, suggesting that the Fe1.5Ti0.5O3 nanoparticle synthesized by this method is a promising anode material for lithium-ion batteries.

  4. Yolk-shell ZnO-C microspheres with enhanced electrochemical performance as anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • ZnO-C yolk-shell microspheres, hollow microspheres and solid microspheres are prepared. • Yolk-shell ZnO-C microspheres possess the best electrochemical properties when used as the anode materials for lithium-ion batteries. • The special yolk-shell structures and extra carbon support account for the enhanced electrochemical properties. - Abstract: Three ZnO-C samples with distinct structures including yolk-shell microspheres, hollow microspheres and solid microspheres are fabricated through a facile chemical solution reaction followed by calcination in argon. When employed as the anode materials for lithium ion batteries, yolk-shell ZnO-C microspheres exhibit the best electrochemical properties than the hollow and solid microspheres. After 150 cycles, yolk-shell ZnO-C microspheres demonstrate a relative high capacity of 520 mA h g−1 at a current density of 100 mA g−1 with a Coulombic efficiency of about 99.3%. The excellent cycling stability and good rate capability of yolk-shell ZnO-C microspheres stem from the synergistic effect of the unique yolk-shell structures and extra carbon support

  5. Ultrahigh capacity anode material for lithium ion battery based on rod gold nanoparticles decorated reduced graphene oxide

    International Nuclear Information System (INIS)

    In this study, we report the synthesis of rod shaped gold nanoparticles/2-aminoethanethiol functionalized reduced graphene oxide composite (rdAuNPs/AETrGO) and its application as an anode material for lithium-ion batteries. The structure of the rdAuNPs/AETrGO composite was characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction. The electrochemical performance was investigated at different current rates by using a coin-type cell. It was found that the rod shaped gold nanoparticles were highly dispersed on the reduced graphene oxide sheets. Moreover, the rdAuNPs/AETrGO composite showed a high specific gravimetric capacity of about 1320 mAh g−1 and a long-term cycle stability. - Highlights: • We prepared rod shaped gold nanoparticles functionalized reduced graphene oxide. • The nanocomposite was used as an anode material for lithium-ion batteries. • The nanocomposite showed a high specific gravimetric capacity of about 1320 mAh g−1. • The nanocomposite exhibited a long-term cycle stability

  6. Trace analysis of Cd, Cu, Pb and Zn in various materials using differential pulse anodic stripping voltammetry

    International Nuclear Information System (INIS)

    Sampling and sample preparation methods have been described. Digestion methods for different types of materials and acid purification systems have been developed. For trace analysis purposes cleaning methods for glassware etc. have been described. Differential pulse anodic stripping voltametric (DPASV) method has been worked out for the trace analysis of zn, cd, pb and Cu in different types of materials. Linearity of the method has been checked by drawing concentration versus currents (peak height) curves. Precision of the method has been checked by analysing a number of actual samples. of the method has been verified by analysing standards of U.S.A. Comparative studies have been done between Differential pulse anodic stripping voltammetric method and Atomic Absorption spectroscopic method. Problems of contamination and systematic errors during trace and ultra-trace analysis have been discussed. A variety of samples including soil, spinach, wheat flour, rice flour, dry milk, coriander, kidney stones, bladder stones etc. have been analysed and preliminary results have been reported. (author)

  7. Poly L-lysine (PLL)-mediated porous hematite clusters as anode materials for improved Li-ion batteries

    Science.gov (United States)

    Kim, Kun-Woo; Lee, Sang-Wha

    2015-09-01

    Porous hematite clusters were prepared as anode materials for improved Li-ion batteries. First, poly-L-lysine (PLL)-linked Fe3O4 was facilely prepared via cross-linking between the positive amine groups of PLL and carboxylate-bound Fe3O4. The subsequent calcination transformed the PLL-linked Fe3O4 into porous hematite clusters (Fe2O3@PLL) consisting of spherical α-Fe2O3 particles. Compared with standard Fe2O3, Fe3O4@PLL exhibited improved electrochemical performance as anode materials. The discharge capacity of Fe2O3@PLL was retained at 814.7 mAh g-1 after 30 cycles, which is equivalent to 80.4% of the second discharge capacity, whereas standard Fe2O3 exhibited a retention capacity of 352.3 mAh g-1. The improved electrochemical performance of Fe2O3@PLL was mainly attributed to the porous hematite clusters with mesoporosity (20-40 nm), which was beneficial for facilitating ion transport, suggesting a useful guideline for the design of porous architectures with higher retention capacity. [Figure not available: see fulltext.

  8. Stainless steel is a promising electrode material for anodes of microbial fuel cells

    OpenAIRE

    Pocaznoi, Diana; Calmet, Amandine; Etcheverry, Luc; Erable, Benjamin; Bergel, Alain

    2012-01-01

    The abilities of carbon cloth, graphite plate and stainless steel to form microbial anodes were compared under identical conditions. Each electrode was polarised at −0.2 V vs. SCE in soil leachate and fed by successive additions of 20 mM acetate. Under these conditions, the maximum current densities provided were on average 33.7 A m−2 for carbon cloth, 20.6 A m−2 for stainless steel, and 9.5 A m−2 for flat graphite. The high current density obtained with carbon cloth was obviously influenced ...

  9. Electrocatalytic Materials and Techniques for the Anodic Oxidation of Various Organic Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Everett Treimer

    2002-06-27

    The focus of this thesis was first to characterize and improve the applicability of Fe(III) and Bi(V) doped PbO{sub 2} film electrodes for use in anodic O-transfer reactions of toxic and waste organic compounds, e.g. phenol, aniline, benzene, and naphthalene. Further, they investigated the use of alternative solution/electrode interfacial excitation techniques to enhance the performance of these electrodes for remediation and electrosynthetic applications. Finally, they have attempted to identify a less toxic metal oxide film that may hold promise for future studies in the electrocatalysis and photoelectrocatalysis of O-transfer reactions using metal oxide film electrodes.

  10. Binder Free SnO2-CNT Composite as Anode Material for Li-Ion Battery

    OpenAIRE

    Dionne Hernandez; Frank Mendoza; Emmanuel Febus; Weiner, Brad R.; Gerardo Morell

    2014-01-01

    Tin dioxide-carbon nanotube (SnO2-CNT) composite films were synthesized on copper substrates by a one-step process using hot filament chemical vapor deposition (HFCVD) with methane gas (CH4) as the carbon source. The composite structural properties enhance the surface-to-volume ratio of SnO2 demonstrating a desirable electrochemical performance for a lithium-ion battery anode. The SnO2 and CNT interactions were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), tran...

  11. Anodic performance in lithium-ion batteries of graphite-like materials prepared from anthracites and unburned carbon concentrates from coal combustion fly ashes

    Directory of Open Access Journals (Sweden)

    I. Cameán

    2013-01-01

    Full Text Available The electrochemical performance as anodes for lithium-ion batteries of graphite-like materials that were prepared from anthracites and unburned carbon concentrates from coal combustion fly ashes by high temperature treatment was investigated by galvanostatic cycling of lithium test cells. Some of the materials prepared have provided reversible capacities up to ~ 310 mA h g-1 after 50 discharge/ charge cycles. These values are similar to those of oil-derived graphite (petroleum coke being the main precursor which is currently used as anodic material in commercial lithium-ion batteries.

  12. Electrospun fibers for high performance anodes in microbial fuel cells. Optimizing materials and architecture

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Shuiliang

    2010-04-15

    A novel porous conducting nanofiber mat (PCNM) with nanostructured polyaniline (nanoPANi) on the fiber surface was successfully prepared by simple oxidative polymerization. The composite PCNM displayed a core/shell structure with highly rough surface. The thickness and the morphology of PANi layer on the electrospun polyamide (PA) fiber surface could be controlled by varying aniline concentration and temperature. The combination of the advantages of electrospinning technique and nanostructured PANi, let the PA/PANi composite PCNM possess more than five good properties, i.e. high conductivity of 6.759 S.m{sup -1}, high specific surface area of 160 m2.g{sup -1}, good strength of 82.88 MPa for mat and 161.75 MPa for highly aligned belts, good thermal properties with 5% weight loss temperature up to 415 C and excellent biocompatibility. In the PA/PANi composite PCNM, PANi is the only conducting component, its conductivity of 6.759 S.m{sup -1} which is measured in dry-state, is not enough for electrode. Moreover, the conductivity decreases in neutral pH environment due to the de-doping of proton. However, the method of spontaneous growth of nanostructured PANi on electrospun fiber mats provides an effective method to produce porous electrically conducting electrospun fiber mats. The combination advantages of nanostructured PANi with the electrospun fiber mats, extends the applications of PANi and electrospun nanofibers, such as chemical- and bio-sensors, actuators, catalysis, electromagnetic shielding, corrosion protection, separation membranes, electro-optic devices, electrochromic devices, tissue engineering and many others. The electrical conductivity of electrospun PCNM with PANi as the only conducting component is too low for application of as anode in microbial fuel cells (MFCs). So, we turn to electrospun carbon fiber due to its high electrical conductivity and environmental stability. The current density is greatly dependent on the microorganism density of anode

  13. Zinc pyridinedicarboxylate micro-nanostructures: Promising anode materials for lithium-ion batteries with excellent cycling performance.

    Science.gov (United States)

    Fei, Hailong; Lin, Yaqin

    2016-11-01

    It is important to discover new, cheap and environmental friendly coordination polymer electrode materials for lithium-ion batteries. Zinc 2,6-pyridilinedicarboxylate particles show better cycling stability and higher discharge capacity than 2,5-pyridilinedicarboxylate micro-platelets when they are firstly tested as anode materials for lithium-ion batteries. The former can steadily cycle at current densities of 750, 1000 and 2000mAg(-1). It is also stable in multiple insertion/extraction processes at current densities of 750, 1500, 2000, 2500, 3000, and 750mAg(-1), and the capacity retention is 77.9% after 60cycles. While the latter is apt to show good cycling performance at smaller discharge current density. PMID:27490195

  14. Electrospinning synthesis of 3D porous NiO nanorods as anode material for lithium-ion batteries

    Directory of Open Access Journals (Sweden)

    Wei Kong Xiang

    2016-06-01

    Full Text Available Three-dimensional NiO nanorods were synthesized as anode material by electrospinning method. X-ray diffraction results revealed that the product sintered at 400 °C had impure metallic nickel phase which, however, became pure NiO phase as the sintering temperature rose. Nevertheless, the nanorods sintered at 400, 500 and 600 °C had similar diameters (∼200 nm.The NiO nanorod material sintered at 500 °C was chip-shaped with a diameter of 200 nm and it exhibited a porous 3D structure. The nanorod sintered at 500 °C had the optimal electrochemical performance. Its discharge specific capacity was 1127 mAh·g−1 initially and remained as high as 400 mAh·g−1 at a current density of 55 mA·g−1 after 50 cycles.

  15. Nanoscale MnO and natural graphite hybrid materials as high-performance anode for lithium ion batteries

    International Nuclear Information System (INIS)

    In this work, MnO and natural graphite (NG) hybrid composite was synthesized via a hydrothermal reaction and a subsequent self-reduction process. As an anode material for lithium ion batteries, MnO/NG composite displays excellent cycling stability and good rate capability. The charge–discharge test showed the highest initial lithiation/delithiation specific capacities of 552.8 and 511.7 mAh · g−1, which were maintained at 494.9 and 497 mAh · g−1 even after 120 cycles, at 0.2 C with a voltage range from 0.01 V to 2.0 V. The lithiation specific capacity was retained 280 mAh · g−1 at 10 C, which extremely precedes the bare NG materials

  16. Development of Low Cost Carbonaceous Materials for Anodes in Lithium-Ion Batteries for Electric and Hybrid Electric Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Barsukov, Igor V.

    2002-12-10

    Final report on the US DOE CARAT program describes innovative R & D conducted by Superior Graphite Co., Chicago, IL, USA in cooperation with researchers from the Illinois Institute of Technology, and defines the proper type of carbon and a cost effective method for its production, as well as establishes a US based manufacturer for the application of anodes of the Lithium-Ion, Lithium polymer batteries of the Hybrid Electric and Pure Electric Vehicles. The three materials each representing a separate class of graphitic carbon, have been developed and released for field trials. They include natural purified flake graphite, purified vein graphite and a graphitized synthetic carbon. Screening of the available on the market materials, which will help fully utilize the graphite, has been carried out.

  17. Research progress in anode materials for Li-ion battery%锂离子电池负极材料的研究进展

    Institute of Scientific and Technical Information of China (English)

    武明昊; 陈剑; 王崇; 衣宝廉

    2011-01-01

    综述了近年来锂离子电池负极材料的研究进展,包括碳材料、过渡金属氧化物,锡基和硅基材料等,重点评述了锡基和硅基材料的研究进展,并对锂离子电池负极材料的发展趋势进行了展望.%Research progress in anode materials for Li-ion battery in recent years, including carbon, transition metal oxides, tin based composites and silicon based composites was reviewed. The research progress in tin based and silicon based anode materials was commented emphatically,the development tendency of Li-ion battery anode materials was prospected.

  18. Hydrothermal growth of Cobalt germanate/reduced graphene oxide nanocomposite as superior anode materials for Lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • The nanosized Co2GeO4 and Co2GeO4/RGO nanocomposites were prepared by a facile one pot hydrothermal route. • The Co2GeO4 and Co2GeO4/RGO nanocomposites could be used as novel high capacity anodes with both alloying and conversion reactions. • The RGO incorporation can improve the electrochemical performance of Co2GeO4 by buffering the volume changes and enhancing the conductivity of the electrodes. • The CGO/RGO nanocomposites exhibit a large reversible capacity of 1250 mAh g−1 for the first cycle and a capacity retention of 1085 mAh g−1 after 100 cycles. Remarkable rate performance was also recorded. - Abstract: Well dispersed Co2GeO4 (CGO) nanoplates and CGO/reduced graphene oxide (RGO) nanocomposites are prepared via hydrothermal method and characterized as novel lithium anode materials for the first time. Electrochemical measurements demonstrate that the CGO/RGO nanocomposites exhibit a large reversible capacity of 1250 mAh g−1 for the first cycle and a capacity retention of 1085 mAh g−1 after 100 cycles. Remarkable rate performance was also recorded. The superior electrochemical performance of the CGO/RGO nanocomposites electrode compared to the pure CGO electrode can be attributed to the well dispersed RGO which enhances the electronic conductivity and accommodate the volume change during the conversion reactions

  19. Lithiation Behavior of High Capacity SiCO Anode Material for Lithium-ion Battery: A First Principle Study

    International Nuclear Information System (INIS)

    Polymer-derived silicon oxycarbide (SiCO) has a reversible capacity of ∼800 mA h g−1 and is considered as a promising anode material for Li-ion battery. Further study needs to be conducted in terms of energy and structure in atomic scale, which could be very challenging for current experimental technologies. To better understand the mechanism of lithium insertion in SiCO, first principle calculations are performed to study the atomic structures, bonding mechanism, mechanical properties and lithiation voltage of lithiated SiC1/4O7/4. The predominate feature of the lithiated configuration is the presence of several Li involved tetrahedrons with the formation of Li−C/Li−O bonds. By the calculations of relative volume and bulk modulus, SiC1/4O7/4 presents a considerably better performance in expansion and mechanical property than Si and SiO1/3. The formation energy and voltage curve also show that the lithium is more preferable in incorporation with SiC1/4O7/4 than Si and SiO1/3, which is attributed to the formation of Li−O, Li−C bonds and corresponding Li involved tetrahedrons. Our calculations are in agreement with the available experiments, and provide a deeper insight into the lithiation mechanism of SiCO anode for Li-ion batteries

  20. Corrosion and Discharge Behaviors of Mg-Al-Zn and Mg-Al-Zn-In Alloys as Anode Materials

    Directory of Open Access Journals (Sweden)

    Jiarun Li

    2016-03-01

    Full Text Available The Mg-6%Al-3%Zn and Mg-6%Al-3%Zn-(1%, 1.5%, 2%In alloys were prepared by melting and casting. Their microstructures were investigated via metallographic and energy-dispersive X-ray spectroscopy (EDS analysis. Moreover, hydrogen evolution and electrochemical tests were carried out in 3.5 wt% NaCl solution aiming at identifying their corrosion mechanisms and discharge behaviors. The results suggested that indium exerts an improvement on both the corrosion rate and the discharge activity of Mg-Al-Zn alloy via the effects of grain refining, β-Mg17Al12 precipitation, dissolving-reprecipitation, and self-peeling. The Mg-6%Al-3%Zn-1.5%In alloy with the highest corrosion rate at free corrosion potential did not perform desirable discharge activity indicating that the barrier effect caused by the β-Mg17Al12 phase would have been enhanced under the conditions of anodic polarization. The Mg-6%Al-3%Zn-1.0%In alloy with a relative low corrosion rate and a high discharge activity is a promising anode material for both cathodic protection and chemical power source applications.

  1. Micro-nanostructured CuO/C spheres as high-performance anode materials for Na-ion batteries.

    Science.gov (United States)

    Lu, Yanying; Zhang, Ning; Zhao, Qing; Liang, Jing; Chen, Jun

    2015-02-14

    In this paper, we report on the synthesis of micro-nanostructured CuO/C spheres by aerosol spray pyrolysis and their application as high-performance anodes in sodium-ion batteries. Micro-nanostructured CuO/C spheres with different CuO contents were synthesized through aerosol spray pyrolysis by adjusting the ratio of reactants and heat-treated by an oxidation process. The as-prepared CuO/C spheres show uniformly spherical morphology, in which CuO nanoparticles (∼10 nm) are homogeneously embedded in the carbon matrix (denoted as 10-CuO/C). The electrochemical performance of 10-CuO/C with a carbon weight of 44% was evaluated as the anode material for Na-ion batteries. It can deliver a capacity of 402 mA h g(-1) after 600 cycles at a current density of 200 mA g(-1). Furthermore, a capacity of 304 mA h g(-1) was obtained at a high current density of 2000 mA g(-1). The superior electrochemical performance of the micro-nanostructured CuO/C spheres leads to the enhancement of the electronic conductivity of the nanocomposite and the accommodation of the volume variation of CuO/C during charge/discharge cycling. PMID:25584745

  2. Interconnected MoO2 nanocrystals with carbon nanocoating as high-capacity anode materials for lithium-ion batteries.

    Science.gov (United States)

    Zhou, Liang; Wu, Hao Bin; Wang, Zhiyu; Lou, Xiong Wen David

    2011-12-01

    A facile one-pot hydrothermal method has been developed for the preparation of carbon-coated MoO(2) nanocrystals. The annealed MoO(2)-C nanocomposite consists of interconnected MoO(2)@C nanocrystals. When evaluated for lithium storage capabilities, these MoO(2)@C nanocrystals exhibit high specific capacities (~640 mA h g(-1) at 200 mA g(-1) and ~575 mA h g(-1) at 400 mA g(-1)) and excellent cycling stability. In view of the excellent lithium storage properties and the ease in large-scale preparation, the as-synthesized MoO(2)-C nanocomposite might be used as promising anode materials for high-performance lithium-ion batteries. PMID:22077330

  3. A novel ZnO@Ag@Polypyrrole hybrid composite evaluated as anode material for zinc-based secondary cell

    Science.gov (United States)

    Huang, Jianhang; Yang, Zhanhong; Feng, Zhaobin; Xie, Xiaoe; Wen, Xing

    2016-04-01

    A novel ZnO@Ag@Polypyrrole nano-hybrid composite has been synthesized with a one-step approach, in which silver-ammonia complex ion serves as oxidant to polymerize the pyrrole monomer. X-ray diffraction (XRD) and infrared spectroscopy (IR) show the existence of metallic silver and polypyrrole. The structure of nano-hybrid composites are characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM), which demonstrates that the surface of ZnO is decorated with nano silver grain coated with polypyrrole. When evaluated as anode material, the silver grain and polypyrrole layer not only suppress the dissolution of discharge product, but also helps to uniform electrodeposition due to substrate effect and its good conductivity, thus shows better cycling performance than bare ZnO electrode does.

  4. Sandwich-like SnS/Polypyrrole Ultrathin Nanosheets as High-Performance Anode Materials for Li-Ion Batteries.

    Science.gov (United States)

    Liu, Jun; Gu, Mingzhe; Ouyang, Liuzhang; Wang, Hui; Yang, Lichun; Zhu, Min

    2016-04-01

    Sandwich-like SnS/polypyrrole ultrathin nanosheets were synthesized via a pyrrole reduction and in situ polymerization route, in which room-temperature synthesized ZnSn(OH)6 microcubes were used as the tin source. As anode materials for Li-ion batteries, they exhibit an extremely high reversible capacity (about 1000 mA h g(-1) at 0.1C), outstanding rate capability (with reversible capabilities of 878, 805, 747, 652, and 576 mA h g(-1) at 0.2C, 0.5C, 1C, 2C, and 5C, respectively), stable cycling performance, and high capacity retention (a high capacity of 703 mA h g(-1) at 1C after long 500 cycles). PMID:26984512

  5. Nanoparticle Decorated Ultrathin Porous Nanosheets as Hierarchical Co3O4 Nanostructures for Lithium Ion Battery Anode Materials

    Science.gov (United States)

    Mujtaba, Jawayria; Sun, Hongyu; Huang, Guoyong; Mølhave, Kristian; Liu, Yanguo; Zhao, Yanyan; Wang, Xun; Xu, Shengming; Zhu, Jing

    2016-02-01

    We report a facile synthesis of a novel cobalt oxide (Co3O4) hierarchical nanostructure, in which crystalline core-amorphous shell Co3O4 nanoparticles with a bimodal size distribution are uniformly dispersed on ultrathin Co3O4 nanosheets. When tested as anode materials for lithium ion batteries, the as-prepared Co3O4 hierarchical electrodes delivered high lithium storage properties comparing to the other Co3O4 nanostructures, including a high reversible capacity of 1053.1 mAhg-1 after 50 cycles at a current density of 0.2 C (1 C = 890 mAg-1), good cycling stability and rate capability.

  6. Graphene-encapsulated porous carbon-ZnO composites as high-performance anode materials for Li-ion batteries

    International Nuclear Information System (INIS)

    As novel anode materials for lithium-ion batteries (LIBs), ZnO-loaded porous carbons (CMK-3 or CMK-8) are prepared by a two-step method and exhibit better electrochemical properties than pure ZnO particles. ZnO nanoparticles are separated inside the pores of porous carbons, which limit the growth of ZnO crystals and accommodate their volume variation during cycles. Moreover, to further improve their electrochemical performances, these composites are further wrapped by graphene nanosheets through a stepwise heterocoagulation method. Compared to uncoated porous carbon-ZnO, graphene-encapsulated porous carbon-ZnO composites exhibit higher reversible capacities, better cycle performances and rate capabilities. The superior performances of graphene-encapsulated composites may be attributed to graphene encapsulation, which enhances the electrical conductivity of the overall electrode, avoids the aggregation of porous carbon-ZnO particles and even stabilizes the mesostructure of porous carbon during cycles

  7. Nanoparticle Decorated Ultrathin Porous Nanosheets as Hierarchical Co3O4 Nanostructures for Lithium Ion Battery Anode Materials.

    Science.gov (United States)

    Mujtaba, Jawayria; Sun, Hongyu; Huang, Guoyong; Mølhave, Kristian; Liu, Yanguo; Zhao, Yanyan; Wang, Xun; Xu, Shengming; Zhu, Jing

    2016-01-01

    We report a facile synthesis of a novel cobalt oxide (Co3O4) hierarchical nanostructure, in which crystalline core-amorphous shell Co3O4 nanoparticles with a bimodal size distribution are uniformly dispersed on ultrathin Co3O4 nanosheets. When tested as anode materials for lithium ion batteries, the as-prepared Co3O4 hierarchical electrodes delivered high lithium storage properties comparing to the other Co3O4 nanostructures, including a high reversible capacity of 1053.1 mAhg(-1) after 50 cycles at a current density of 0.2 C (1 C = 890 mAg(-1)), good cycling stability and rate capability. PMID:26846434

  8. Nb{sub 2}O{sub 5} hollow nanospheres as anode material for enhanced performance in lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Sasidharan, Manickam [Department of Chemistry, Faculty of Science and Engineering, Saga University, 1 Honjo-machi, Saga 840-8502 (Japan); Gunawardhana, Nanda [Advanced Research Center, Saga University, 1341 Yoga-machi, Saga 840-0047 (Japan); Yoshio, Masaki, E-mail: yoshio@cc.saga-u.ac.jp [Advanced Research Center, Saga University, 1341 Yoga-machi, Saga 840-0047 (Japan); Nakashima, Kenichi, E-mail: nakashik@cc.saga-u.ac.jp [Department of Chemistry, Faculty of Science and Engineering, Saga University, 1 Honjo-machi, Saga 840-8502 (Japan)

    2012-09-15

    Graphical abstract: Nb{sub 2}O{sub 5} hollow nanosphere constructed electrode delivers high capacity of 172 mAh g{sup −1} after 250 cycles and maintains structural integrity and excellent cycling stability. Highlights: ► Nb{sub 2}O{sub 5} hollow nanospheres synthesis was synthesized by soft-template. ► Nb{sub 2}O{sub 5} hollow nanospheres were investigated as anode material in Li-ion battery. ► Nanostructured electrode delivers high capacity of 172 mAh g{sup −1} after 250 cycles. ► The electrode maintains the structural integrity and excellent cycling stability. ► Nanosized shell domain facilitates fast lithium intercalation/deintercalation. -- Abstract: Nb{sub 2}O{sub 5} hollow nanospheres of average diameter ca. ∼29 nm and hollow cavity size ca. 17 nm were synthesized using polymeric micelles with core–shell–corona architecture under mild conditions. The hollow particles were thoroughly characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), infrared spectroscopy (FTIR), thermal (TG/DTA) and nitrogen adsorption analyses. Thus obtained Nb{sub 2}O{sub 5} hollow nanospheres were investigated as anode materials for lithium ion rechargeable batteries for the first time. The nanostructured electrode delivers high capacity of 172 mAh g{sup −1} after 250 cycles of charge/discharge at a rate of 0.5 C. More importantly, the hollow particles based electrodes maintains the structural integrity and excellent cycling stability even after exposing to high current density 6.25 A g{sup −1}. The enhanced electrochemical behavior is ascribed to hollow cavity coupled with nanosized Nb{sub 2}O{sub 5} shell domain that facilitates fast lithium intercalation/deintercalation kinetics.

  9. Facile Fabrication of 3D SiO2@Graphene Aerogel Composites as Anode Material for Lithium Ion Batteries

    International Nuclear Information System (INIS)

    Highlights: • Three-dimensional amorphous SiO2@GA ultralight composite was prepared via a one-pot route. • SiO2@GA exhibited high surface area, large pore volume, and narrow meso-macoporous size distribution. • SiO2@GA electrode exhibited high specific capacity and stable cycling performance. • SiO2@GA electrode displayed excellent rate-capability. - Abstract: A three-dimensional amorphous SiO2@graphene aerogel (SiO2@GA) composites as anode material for lithium ion batteries was successfully synthesized via a one-pot process. The materials were characterized by nitrogen adsorption-desorption, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectra and Fourier-Transform infrared spectra. The results demonstrate that the SiO2@GA composites are in meso-macoporous structures and present large surface area (SBET = 396.9 m2 g−1) and high pore volume (Vp = 0.67 cm3 g−1). Meanwhile, the incorporation of SiO2 does not make obvious effect at the reduction degree of GO to assemble GA. The results of their electrochemical performance reveal that in contrast with bare SiO2, the SiO2@GA anode exhibit higher reversible capacity (∼300 mAh g−1 at a current density of 500 mA g−1), more stable cycling performance, and excellent rate-capability. The significantly improves electrochemical performance may be ascribed to the 3D aerogel structure and the doping of GA

  10. Anodes for alkaline electrolysis

    Science.gov (United States)

    Soloveichik, Grigorii Lev

    2011-02-01

    A method of making an anode for alkaline electrolysis cells includes adsorption of precursor material on a carbonaceous material, conversion of the precursor material to hydroxide form and conversion of precursor material from hydroxide form to oxy-hydroxide form within the alkaline electrolysis cell.

  11. Facile complex-coprecipitation synthesis of mesoporous Fe3O4 nanocages and their high lithium storage capacity as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    A facile complex-coprecipitation synthesis of mesoporous Fe3O4 nanocages and their high capacities and excellent cycling performance as anode material for LIBs are reported. - Highlights: • MFONs are synthesized by a facile complex-coprecipitation method. • MFONs with high surface area lead to excellent electrochemical performance. • MFONs anode retains a capacity of 573 mAh g−1 at 1 A g−1 after 300 cycles. - Abstract: In this study, high-quality mesoporous Fe3O4 nanocages (MFONs) have been synthesized by a facile complex-coprecipitation method at 100 °C with addition of triethanolamine and ethylene glycol. The as-prepared Fe3O4 nanocages possess a mesoporous structure and highly uniform dispersion. When used as an anode material for rechargeable lithium-ion batteries, MFONs anode shows high specific capacities and excellent cycling performance at high and low current rates. At a current density of 200 mA g−1, the discharge specific capacities are 876 mAh g−1 at the 2nd cycle and 830 mAh g−1 at the 100th cycle. Even at the high current density of 1000 mA g−1, MFONs anode still retains a stable capacity of 573 mAh g−1 after 300 cycles. This superior electrochemical performance is attributed to the unique mesoporous cage-like structure and high specific surface area (133 m2 g−1) of MFONs, which may offer large electrode/electrolyte contact area for the electron conduction and Li+ storage. Furthermore, the good mechanical flexibility of the mesoporous nanocages can readily buffer the massive volume expansion/shrinkage associated with the reversible electrode reaction. These results indicate that MFONs can be used as a promising high-performance anode material for lithium-ion batteries

  12. Electrochemical performance and lithium-ion insertion/extraction mechanism studies of the novel Li2ZrO3 anode materials

    International Nuclear Information System (INIS)

    Li2ZrO3 anode materials were prepared by the conventional solid-state reaction. The crystal structure has been determined by X-ray diffraction. Electrochemical tests show that Li2ZrO3 anode materials process a excellent cycle performance and rate capability due to the good structural stability and high lithium diffusion coefficients. For the Li2ZrO3 anode material, the change of the unit cell volume is only ∼0.3% at discharge or charge process. Except for the first several cycles, the coulombic efficiency of the Li2ZrO3 electrode was nearly 100% at a discharge/charge rate of 0.3 C. The lithium diffusion coefficients of Li2ZrO3 for the reduction and oxidation process are calculated to be 3.165 × 10−6 and 1.919 × 10−6 cm2 s−1 respectively which is much higher than that of the Li4Ti5O12 anode material (about 10−9 to 10−13 cm2 s−1). In situ XRD results, combined the sloping character of the charge/discharge voltage profiles and the lithium ion diffusion controlled mechanism in the charge and discharge process, show that the insertion/extraction mechanism of Li+ for Li2ZrO3 can be interpreted as a solid-solution behavior

  13. Nanoparticle Decorated Ultrathin Porous Nanosheets as Hierarchical Co3O4 Nanostructures for Lithium Ion Battery Anode Materials

    DEFF Research Database (Denmark)

    Mujtaba, Jawayria; Sun, Hongyu; Huang, Guoyong;

    2016-01-01

    We report a facile synthesis of a novel cobalt oxide (Co3O4) hierarchical nanostructure, in which crystalline core-amorphous shell Co3O4 nanoparticles with a bimodal size distribution are uniformly dispersed on ultrathin Co3O4 nanosheets. When tested as anode materials for lithium ion batteries...

  14. Ionic liquid-assisted solvothermal synthesis of hollow Mn2O3 anode and LiMn2O4 cathode materials for Li-ion batteries

    Science.gov (United States)

    He, Xin; Wang, Jun; Jia, Haiping; Kloepsch, Richard; Liu, Haidong; Beltrop, Kolja; Li, Jie

    2015-10-01

    Mn-based Mn2O3 anode and LiMn2O4 cathode materials are prepared by a solvothermal method combined with post annealing process. Environmentally friendly ionic liquid 1-Butyl-3-methylimidazolium tetrafluoroborate as both structure-directing agent and fluorine source is used to prepare hollow polyhedron MnF2 precursor. Both target materials Mn2O3 anode and LiMn2O4 cathode have the morphology of the MnF2 precursor. The Mn2O3 anode using carboxymethyl cellulose as binder could deliver slight better electrochemical performance than the one using poly (vinyldifluoride) as binder. The former has an initial charge capacity of 800 mAh g-1 at a current density of 101.8 mA g-1, and exhibits no obvious capacity decay for 150 cycles at 101.8 mA g-1. The LiMn2O4 cathode material prepared with molten salt assistant could display much better electrochemical performance than the one prepared without molten salt assistance. In particular, it has an initial discharge capacity of 117.5 mAh g-1 at a current density of 0.5C and good rate capability. In the field of lithium ion batteries, both the Mn2O3 anode and LiMn2O4 cathode materials could exhibit enhanced electrochemical performance due to the well formed morphology based on the ionic liquid-assisted solvothermal method.

  15. Micro-nanostructured CuO/C spheres as high-performance anode materials for Na-ion batteries

    Science.gov (United States)

    Lu, Yanying; Zhang, Ning; Zhao, Qing; Liang, Jing; Chen, Jun

    2015-01-01

    In this paper, we report on the synthesis of micro-nanostructured CuO/C spheres by aerosol spray pyrolysis and their application as high-performance anodes in sodium-ion batteries. Micro-nanostructured CuO/C spheres with different CuO contents were synthesized through aerosol spray pyrolysis by adjusting the ratio of reactants and heat-treated by an oxidation process. The as-prepared CuO/C spheres show uniformly spherical morphology, in which CuO nanoparticles (~10 nm) are homogeneously embedded in the carbon matrix (denoted as 10-CuO/C). The electrochemical performance of 10-CuO/C with a carbon weight of 44% was evaluated as the anode material for Na-ion batteries. It can deliver a capacity of 402 mA h g-1 after 600 cycles at a current density of 200 mA g-1. Furthermore, a capacity of 304 mA h g-1 was obtained at a high current density of 2000 mA g-1. The superior electrochemical performance of the micro-nanostructured CuO/C spheres leads to the enhancement of the electronic conductivity of the nanocomposite and the accommodation of the volume variation of CuO/C during charge/discharge cycling.In this paper, we report on the synthesis of micro-nanostructured CuO/C spheres by aerosol spray pyrolysis and their application as high-performance anodes in sodium-ion batteries. Micro-nanostructured CuO/C spheres with different CuO contents were synthesized through aerosol spray pyrolysis by adjusting the ratio of reactants and heat-treated by an oxidation process. The as-prepared CuO/C spheres show uniformly spherical morphology, in which CuO nanoparticles (~10 nm) are homogeneously embedded in the carbon matrix (denoted as 10-CuO/C). The electrochemical performance of 10-CuO/C with a carbon weight of 44% was evaluated as the anode material for Na-ion batteries. It can deliver a capacity of 402 mA h g-1 after 600 cycles at a current density of 200 mA g-1. Furthermore, a capacity of 304 mA h g-1 was obtained at a high current density of 2000 mA g-1. The superior

  16. Preparation and electrochemical performance of bramble-like ZnO array as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    A bramble-like ZnO array with a special three-dimensional (3D) nanostructure was successfully fabricated on Zn foil through a facile two-step hydrothermal process. A possible growth mechanism of the bramble-like ZnO array was proposed. In the first step of hydrothermal process, the crystal nucleus of Zn(OH)42− generated by the zinc atoms and OH− ions fold together preferentially along the positive polar (0001) to form the needle-like ZnO array. In the second step of hydrothermal process, the crystal nuclei of Zn(OH)42− adjust their posture to keep their c-axes vertical to the perching sites due to the sufficient environmental force and further grow preferentially along the (0001) direction so as to form bramble-like ZnO array. The electrochemical properties of the needle- and bramble-like ZnO arrays as anode materials for lithium-ion batteries were investigated and compared. The results show that the bramble-like ZnO material exhibits much better lithium storage properties than the needle-like ZnO sample. Reasons for the enhanced electrochemical performance of the bramble-like ZnO material were investigated

  17. Mn 3 O 4 −Graphene Hybrid as a High-Capacity Anode Material for Lithium Ion Batteries

    KAUST Repository

    Wang, Hailiang

    2010-10-13

    We developed two-step solution-phase reactions to form hybrid materials of Mn3O4 nanoparticles on reduced graphene oxide (RGO) sheets for lithium ion battery applications. Selective growth of Mn3O 4 nanoparticles on RGO sheets, in contrast to free particle growth in solution, allowed for the electrically insulating Mn3O4 nanoparticles to be wired up to a current collector through the underlying conducting graphene network. The Mn3O4 nanoparticles formed on RGO show a high specific capacity up to ∼900 mAh/g, near their theoretical capacity, with good rate capability and cycling stability, owing to the intimate interactions between the graphene substrates and the Mn 3O4 nanoparticles grown atop. The Mn3O 4/RGO hybrid could be a promising candidate material for a high-capacity, low-cost, and environmentally friendly anode for lithium ion batteries. Our growth-on-graphene approach should offer a new technique for the design and synthesis of battery electrodes based on highly insulating materials. © 2010 American Chemical Society.

  18. Nanoporous anodic aluminum oxide as a promising material for the electrostatically-controlled thin film interference filter

    International Nuclear Information System (INIS)

    This study presents the approach to implement the electrostatically-controlled thin film optical filter by using a nanoporous anodic aluminum oxide (np-AAO) layer as the key suspended micro structure. The bi-stable optical filter operates in the visible spectral range. In this work, the presented bi-stable optical filter has averaged reflectivity of 60%, and the central wavelengths are 580 and 690 nm respectively for on and off states. The presented np-AAO layer offers the following merits for the thin film optical filter: (1) material properties of np-AAO film, such as refractive index, elastic modulus and dielectric constant, can be easily changed by a low temperature pore-widening process, (2) in-use stiction of the suspended np-AAO structure can be reduced by the small contact area of nanoporous textures, (3) driving (pull-in) voltage can be reduced due to a large dielectric constant (εAAO is 7.05) and small stiffness of np-AAO film and (4) dielectric charging can be reduced by the np-AAO material; thus the offset voltage is small. The study reports the design, fabrication and experimental results of the bi-stable optical filter to demonstrate the advantages of the presented device. The np-AAO material also has the potential for applications of other electrostatic drive micro devices. (paper)

  19. Preparation of graphene/TiO2 anode materials for lithium-ion batteries by a novel precipitation method

    International Nuclear Information System (INIS)

    Graphical abstract: Large-scale preparation of graphene/TiO2 composites was carried out by precipitation method using graphene oxide nanosheet, Ti(SO4)2 and NH3H2O as starting materials. Highlights: ► We use cheap graphene oxides, Ti(SO4)2 and NH3H2O as starting materials for preparation of graphene/TiO2 composites. ► The reversible capacity and the cycling stability of the TiO2 are improved by graphene additive. ► Shorter diffusion length and a larger contact area of graphene/TiO2 result in excellent electrochemical performance. -- Abstract: This paper reports a large-scale production route for graphene/TiO2 nanocomposites using water-based in situ precipitation method. In this method, freshly prepared graphene oxides/TiO2 obtained by precipitating Ti(SO4)2 with NH3H2O was subjected to heat treatment in the presence of N2, which resulted in the formation of graphene/TiO2 nanocomposites. Graphene/TiO2 composites prepared by our method were found to be suitable as anode materials for lithium ion batteries because of its stable cycling performance and high capacity.

  20. Preparation and electrochemical performance of bramble-like ZnO array as anode materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Junfeng [Northwest University, School of Information Science and Technology (China); Wang, Gang [Northwest University, Institute of Photonics & Photon-Technology (China); Wang, Hui, E-mail: huiwang@nwu.edu.cn [Northwest University, College of Chemistry and Materials Science (China); Zhang, Zhiyong; Ruan, Xiongfei; Zhao, Wu; Yun, Jiangni; Xu, Manzhang [Northwest University, School of Information Science and Technology (China)

    2015-01-15

    A bramble-like ZnO array with a special three-dimensional (3D) nanostructure was successfully fabricated on Zn foil through a facile two-step hydrothermal process. A possible growth mechanism of the bramble-like ZnO array was proposed. In the first step of hydrothermal process, the crystal nucleus of Zn(OH){sub 4}{sup 2−} generated by the zinc atoms and OH{sup −} ions fold together preferentially along the positive polar (0001) to form the needle-like ZnO array. In the second step of hydrothermal process, the crystal nuclei of Zn(OH){sub 4}{sup 2−} adjust their posture to keep their c-axes vertical to the perching sites due to the sufficient environmental force and further grow preferentially along the (0001) direction so as to form bramble-like ZnO array. The electrochemical properties of the needle- and bramble-like ZnO arrays as anode materials for lithium-ion batteries were investigated and compared. The results show that the bramble-like ZnO material exhibits much better lithium storage properties than the needle-like ZnO sample. Reasons for the enhanced electrochemical performance of the bramble-like ZnO material were investigated.

  1. Interconnected sandwich structure carbon/Si-SiO2/carbon nanospheres composite as high performance anode material for lithium-ion batteries

    Institute of Scientific and Technical Information of China (English)

    Yuanjin Du; Mengyan Hou; Dandan Zhou; Yonggang Wang; Congxiao Wang; Yongyao Xia

    2014-01-01

    In the present work, an interconnected sandwich carbon/Si-SiO2/carbon nanospheres composite was prepared by template method and carbon thermal vapor deposition (TVD). The carbon conductive layer can not only efficiently improve the electronic conductivity of Si-based anode, but also play a key role in alleviating the negative effect from huge volume expansion over discharge/charge of Si-based anode. The resulting material delivered a reversible capacity of 1094 mAh/g, and exhibited excellent cycling stability. It kept a reversible capacity of 1050 mAh/g over 200 cycles with a capacity retention of 96%.

  2. Preparation and electrochemical evaluation of manganese ferrite spheres as anode materials for half and full lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • MnFe2O4 spheres are prepared by a facile two-step route. • The MnFe2O4 spheres show excellent electrochemical properties in half cell system. • The integrity of MnFe2O4 electrode could be maintained after the rate test. • The MnFe2O4 anode works well in full cell system with LiCoO2 as cathode. - Abstract: A simple hydrothermal method combined with a post annealing treatment is developed to produce high crystallinity manganese ferrite (MnFe2O4) spheres. The lithium storage properties of the material as an anode in both half and full lithium-ion batteries are investigated. And the electrochemical behaviors of the electrode during lithiation and delithiation process are clarified. Benefited from its sphere-like morphology, the MnFe2O4 electrode exhibits better lithium storage exhibitions than commercial MnFe2O4 particles in half cell system. When assembled with LiCoO2 to construct a full lithium-ion battery (LiCoO2//MnFe2O4), the spheres could deliver a reversible capacity of higher than 600 mA h g−1 at a current density of 0.1 A g−1 in the potential range of 1.2–3.8 V. This work clearly demonstrates the possibility of using LiCoO2//MnFe2O4 configuration for practical high-performance lithium-ion batteries in the near future

  3. High capacity disordered carbons obtained from coconut shells as anode materials for lithium batteries

    International Nuclear Information System (INIS)

    Carbonaceous materials have been obtained by the pyrolysis of coconut shells at 800 and 900 deg. C with pore forming substances such as KOH and ZnCl2. The prepared carbons were subjected to XRD, SEM, BET-surface area and charge-discharge studies. The structure and morphology were greatly changed by porogens, which in turn influence the electrochemical properties of the carbonaceous materials. Nanocrystalline tin (Sn) particles were prepared by chemical reduction method. The cycling tests showed that the addition of nanotin with the active material offers a stable cycling behavior. The electrochemical impedance spectra for the Li/C cells have been made and the results are discussed

  4. Three-dimensional tungsten nitride nanowires as high performance anode material for lithium ion batteries

    Science.gov (United States)

    Zhang, Min; Qiu, Yongfu; Han, Yi; Guo, Yan; Cheng, Faliang

    2016-08-01

    Nanostructure materials often achieve low capacity when the active material mass loading is high. In this communication, high mass-loading tungsten nitride nanowires (WNNWs) were fabricated on a flexible carbon cloth by hydrothermal method and post annealing. The prepared electrode exhibited remarkable cyclic stability and attractive rate capability for lithium storage. It delivers at a current density of 200 mA g-1, a high capacity of 418 mAh g-1, which is higher than that of conventional graphite. This research opens more opportunity for the fabrication of three-dimensional metal nitrides as negative electrode material for flexible lithium ion batteries.

  5. Preparation and prop erties of Ce0.8Ca0.2O1.8 anode material by glycine-nitrate process

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Ce0.8Ca0.2O1.8 (CDC82) anode material was prepared by glycine-nitrate process(GNP). Thermogravimetric(TG) analysis and differential scanning calorimetric(DSC) methods were adopted to characterize the reaction process of CDC82 material. X-ray diffractometry(XRD), scanning electron microcopy(SEM), direct current four probe (four-probe DC) and temperature process reduce(TPR) techniques were adopted to characterize the properties of CDC82 material. After the precursor was sintered at 750 ℃for 4 h, CDC82 material with pure-fluorite structure and nanometer size was obtained. The total conductivity of CDC82 changes little with temperature in air at 50-850 ℃, and the maximum value is 0.04 S/cm at 750 ℃. The total conductivity wholly becomes larger when the atmosphere changes from air to hydrogen, which greatly increases with increasing temperature and reaches the maximum value of 1.09 S/cm at 850 ℃. Some impurities such as CeMg and La2O3 exist after the mixture of CDC82 anode and La1-xSrxGa1-yMgyO3-δ (LSGM) electrolyte material is sintered at 1 200 ℃ for 15 h. The CDC82 material as anode material has excellent catalytic property for hydrogen and methane.

  6. Electrochemical Properties of Chemically Processed SiOx as Coating Material in Lithium-Ion Batteries with Si Anode

    Directory of Open Access Journals (Sweden)

    Hee-June Jeong

    2014-01-01

    Full Text Available A SiOx coating material for Si anode in lithium-ion battery was processed by using SiCl4 and ethylene glycol. The produced SiOx particles after heat treatment at 725°C for 1 h were porous and irregularly shaped with amorphous structure. Pitch carbon added to SiOx was found to strongly affect solid electrolyte interphase stabilization and cyclic stability. When mixed with an optimal amount of 30 wt% pitch carbon, the SiOx showed a high charge/discharge cyclic stability of about 97% for the 2nd to the 50th cycle. The initial specific capacity of the SiOx was measured to be 1401 mAh/g. On the basis of the evaluation of the SiOx coating material, the process utilized in this study is considered an efficient method to produce SiOx with high performance in an economical way.

  7. Double carbon decorated lithium titanate as anode material with high rate performance for lithium-ion batteries

    Institute of Scientific and Technical Information of China (English)

    Haifang Ni; Weili Song; Lizhen Fan n

    2016-01-01

    Spinel lithium titanate (Li4Ti5O12) has the advantages of structural stability, however it suffers the dis-advantages of low lithium-ion diffusion coefficient as well as low conductivity. In order to solve issues, we reported a simple method to prepare carbon-coated Li4Ti5O12/CNTs (C@Li4Ti5O12/CNTs) using stearic acid as surfactant and carbon source to prepare carbon coated nanosized particles. The obtained Li4Ti5O12 particles of 100 nm in size are coated with the carbon layers pyrolyzed from stearic acid and dispersed in CNTs matrix homogeneously. These results show that the synthesized C@Li4Ti5O12/CNTs material used as anode materials for lithium ion batteries, presenting a better high-rate performance (147 mA h g ? 1 at 20 C). The key factors affecting the high-rate properties of the C@Li4Ti5O12/CNTs composite may be re-lated to the synergistic effects of the CNTs matrix and the carbon-coating layers with conductivity en-hancement. Additionally, the amorphous carbon coating is an effective route to ameliorate the rate capability of Li4Ti5O12/CNTs.

  8. Unique Urchin-like Ca2Ge7O16 Hierarchical Hollow Microspheres as Anode Material for the Lithium Ion Battery

    OpenAIRE

    Dan Li; Chuanqi Feng; Hua Kun Liu; Zaiping Guo

    2015-01-01

    Germanium is an outstanding anode material in terms of electrochemical performance, especially rate capability, but its developments are hindered by its high price because it is rare in the crust of earth, and its huge volume variation during the lithium insertion and extraction. Introducing other cheaper elements into the germanium-based material is an efficient way to dilute the high price, but normally sacrifice its electrochemical performance. By the combination of nanostructure design an...

  9. Electrochemical characterization of carbon coated bundle-type silicon nanorod for anode material in lithium ion secondary batteries

    Energy Technology Data Exchange (ETDEWEB)

    Halim, Martin [Center for Energy Convergence, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Energy and Environmental Engineering, Korea University of Science and Technology, Gwahangno, Yuseong-gu, Daejeon, 305-333 (Korea, Republic of); Kim, Jung Sub [Center for Energy Convergence, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Department of Material Science & Engineering, Korea University, Seoul 136-713 (Korea, Republic of); Choi, Jeong-Gil [Department of Chemical Engineering, Hannam University, 461-1 Junmin-dong, Yusung-gu, Taejon 305-811 (Korea, Republic of); Lee, Joong Kee, E-mail: leejk@kist.re.kr [Center for Energy Convergence, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Energy and Environmental Engineering, Korea University of Science and Technology, Gwahangno, Yuseong-gu, Daejeon, 305-333 (Korea, Republic of)

    2015-04-15

    Highlights: • Bundle-type silicon nanorods (BSNR) were synthesized by metal assisted chemical etching. • Novel bundle-type nanorods electrode showed self-relaxant characteristics. • The self-relaxant property was enhanced by increasing the silver concentration. • PAA binder enhanced the self-relaxant property of the silicon material. • Carbon coated BSNR (BSNR@C) has evidently provided better cycle performance. - Abstract: Nanostructured silicon synthesis by surface modification of commercial micro-powder silicon was investigated in order to reduce the maximum volume change over cycle. The surface of micro-powder silicon was modified using an Ag metal-assisted chemical etching technique to produce nanostructured material in the form of bundle-type silicon nanorods. The volume change of the electrode using the nanostructured silicon during cycle was investigated using an in-situ dilatometer. Our result shows that nanostructured silicon synthesized using this method showed a self-relaxant characteristic as an anode material for lithium ion battery application. Moreover, binder selection plays a role in enhancing self-relaxant properties during delithiation via strong hydrogen interaction on the surface of the silicon material. The nanostructured silicon was then coated with carbon from propylene gas and showed higher capacity retention with the use of polyacrylic acid (PAA) binder. While the nano-size of the pore diameter control may significantly affect the capacity fading of nanostructured silicon, it can be mitigated via carbon coating, probably due to the prevention of Li ion penetration into 10 nano-meter sized pores.

  10. Electrochemical characterization of carbon coated bundle-type silicon nanorod for anode material in lithium ion secondary batteries

    International Nuclear Information System (INIS)

    Highlights: • Bundle-type silicon nanorods (BSNR) were synthesized by metal assisted chemical etching. • Novel bundle-type nanorods electrode showed self-relaxant characteristics. • The self-relaxant property was enhanced by increasing the silver concentration. • PAA binder enhanced the self-relaxant property of the silicon material. • Carbon coated BSNR (BSNR@C) has evidently provided better cycle performance. - Abstract: Nanostructured silicon synthesis by surface modification of commercial micro-powder silicon was investigated in order to reduce the maximum volume change over cycle. The surface of micro-powder silicon was modified using an Ag metal-assisted chemical etching technique to produce nanostructured material in the form of bundle-type silicon nanorods. The volume change of the electrode using the nanostructured silicon during cycle was investigated using an in-situ dilatometer. Our result shows that nanostructured silicon synthesized using this method showed a self-relaxant characteristic as an anode material for lithium ion battery application. Moreover, binder selection plays a role in enhancing self-relaxant properties during delithiation via strong hydrogen interaction on the surface of the silicon material. The nanostructured silicon was then coated with carbon from propylene gas and showed higher capacity retention with the use of polyacrylic acid (PAA) binder. While the nano-size of the pore diameter control may significantly affect the capacity fading of nanostructured silicon, it can be mitigated via carbon coating, probably due to the prevention of Li ion penetration into 10 nano-meter sized pores

  11. Effects of phosphorous incorporation on the microstructure of Si nanoparticles as an anode material for lithium-ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Chun-young; Koo, Jeong-boon [Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon 304-343 (Korea, Republic of); Graduate School of Energy Science and Technology, Chungnam National University, 99 Deahak-ro Yuseong-gu, Daejeon 305-764 (Korea, Republic of); Jang, Bo-yun, E-mail: byjang@kier.re.kr [Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon 304-343 (Korea, Republic of); Kim, Joon-soo; Lee, Jin-seok [Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon 304-343 (Korea, Republic of); Kim, Sung-soo; Han, Moon-hee [Graduate School of Energy Science and Technology, Chungnam National University, 99 Deahak-ro Yuseong-gu, Daejeon 305-764 (Korea, Republic of)

    2015-07-31

    Si nanoparticles were synthesized by inductively coupled plasma and a specially designed double tube reactor. By injection of large amount of PH{sub 3} during the synthesis, the effects of phosphorous incorporation on their microstructures and chemical binding environments were investigated. Injection of PH{sub 3} gas during the synthesis resulted in a change from crystalline to amorphous phase, a reduction of particle size as well as a process yield. All of the above results were attributed to a lower plasma density when higher amount of PH{sub 3} was injected. From energy-dispersive X-ray spectroscopy, secondary ion mass spectrometry, and X-ray photoelectron spectroscopy analysis, it was revealed that P was doped in Si nanoparticles. However, secondary phases such as P{sub 4} and P{sub 2}O{sub 5} were formed as amorphous ones in nano-scale when a relatively large amount of PH{sub 3} was injected. In addition, those nanoparticles were applied as an active material in the lithium-ion battery's anode. Unexpectedly, amorphous Si nanoparticles with secondary phases showed improved electrochemical properties. P-doping in Si nanoparticles could not directly advance cycling performance by improvement of electrical conductivity of Si nanoparticles. It was rather assumed that a secondary phase influenced and enhanced electrochemical properties by additional capacity due to a formation of Li{sub 3}P and forming an effective buffer against large volumetric change of Si nanoparticles during the charge/discharge. The initial reversible capacity of amorphous Si nanoparticles synthesized with 100 sccm of PH{sub 3} flow rate was 2113 mAh g{sup −1}, and that at the 100th cycle was still about 1000 mAh g{sup −1}, which was twice as high as that of Si nanoparticles synthesized without PH{sub 3} injection. - Highlights: • Silicon nanoparticles with phosphorous were synthesized by inductively coupled plasma. • Effects of phosphorous incorporation on the microstructure

  12. Effects of phosphorous incorporation on the microstructure of Si nanoparticles as an anode material for lithium-ion battery

    International Nuclear Information System (INIS)

    Si nanoparticles were synthesized by inductively coupled plasma and a specially designed double tube reactor. By injection of large amount of PH3 during the synthesis, the effects of phosphorous incorporation on their microstructures and chemical binding environments were investigated. Injection of PH3 gas during the synthesis resulted in a change from crystalline to amorphous phase, a reduction of particle size as well as a process yield. All of the above results were attributed to a lower plasma density when higher amount of PH3 was injected. From energy-dispersive X-ray spectroscopy, secondary ion mass spectrometry, and X-ray photoelectron spectroscopy analysis, it was revealed that P was doped in Si nanoparticles. However, secondary phases such as P4 and P2O5 were formed as amorphous ones in nano-scale when a relatively large amount of PH3 was injected. In addition, those nanoparticles were applied as an active material in the lithium-ion battery's anode. Unexpectedly, amorphous Si nanoparticles with secondary phases showed improved electrochemical properties. P-doping in Si nanoparticles could not directly advance cycling performance by improvement of electrical conductivity of Si nanoparticles. It was rather assumed that a secondary phase influenced and enhanced electrochemical properties by additional capacity due to a formation of Li3P and forming an effective buffer against large volumetric change of Si nanoparticles during the charge/discharge. The initial reversible capacity of amorphous Si nanoparticles synthesized with 100 sccm of PH3 flow rate was 2113 mAh g−1, and that at the 100th cycle was still about 1000 mAh g−1, which was twice as high as that of Si nanoparticles synthesized without PH3 injection. - Highlights: • Silicon nanoparticles with phosphorous were synthesized by inductively coupled plasma. • Effects of phosphorous incorporation on the microstructure were studied. • Silicon nanoparticles were applied as an anode material

  13. In Situ Hydrothermal Synthesis of Mn3O4 Nanoparticles on Nitrogen-doped Graphene as High-Performance Anode materials for Lithium Ion Batteries

    International Nuclear Information System (INIS)

    Highlights: • We present a facile process to synthesize Mn3O4/N-doped graphene hybrid materials by hydrothermal route. • Mn3O4/N-doped graphene hybrid materials exhibit a large reversible capacity of about 828 mA h g−1 after 40 cycles. • Mn3O4/graphene hybrid materials demonstrate great potential for lithium ion battery anodes. - Abstract: Developing new electrode materials with high specific capacity for excellent lithium ion storage properties is very desirable. In this paper, we introduce a simple hydrothermal method for the growth of Mn3O4 nanoparticles onto nitrogen-doped graphene (N-doped graphene) for high-performance lithium ion battery (LIB) anodes. Hydrazine plays a fundamental role in the formation of such nanostructures as it can act both as a reducing agent and as a nitrogen source. In the synthesized composite, highly crystalline Mn3O4 nanoparticles with average sizes of 20–50 nm are homogeneously dispersed on both sides of the N-doped graphene. The nitrogen content in the doped graphene is confirmed by elemental analyzer, and 2 wt% of the sample is found to be composed of nitrogen element. The as-prepared Mn3O4/N-doped graphene composites exhibit remarkable electrochemical performance, including high reversible specific capacity, outstanding cycling stability, and excellent rate capability (approximately 400 mA h g−1 at 2.0 A g−1) when used as the anode material for LIBs. The improvement in the electrochemical properties of the material can be attributed to graphene, which acts as both an electron conductor and a volume buffer layer, and nitrogen doping allows for fast electron and ion transfer by decreasing the energy barrier. This type of metal oxide/N-doped graphene composites can be promising candidates for high-performance anode materials for LIBs

  14. Tantalum carbide as a novel support material for anode electrocatalysts in polymer electrolyte membrane water electrolysers

    DEFF Research Database (Denmark)

    Polonský, Jakub; Petrushina, Irina; Christensen, Erik;

    2012-01-01

    study an approach to utilising a suitable electrocatalyst support was followed. Of the materials selected from a literature review, TaC has proved to be stable under the conditions of the accelerated stability test proposed in this study. The test involved dispersing each potential support material in a...... thermogravimmetric and differential thermal analysis to prove its thermal stability. A modified version of the Adams fusion method was used to deposit IrO2 on the support surface. A series of electrocatalysts was prepared with a composition of (IrO2)x(TaC)1−x, where x represents the mass fraction of IrO2 and was...... the electrocatalysts prepared. The electrocatalysts with x ≥ 0.5 showed stable specific activity. This result is consistent with the conductivity measurements....

  15. A Core-Shell Fe/Fe2 O3 Nanowire as a High-Performance Anode Material for Lithium-Ion Batteries.

    Science.gov (United States)

    Na, Zhaolin; Huang, Gang; Liang, Fei; Yin, Dongming; Wang, Limin

    2016-08-16

    The preparation of novel one-dimensional core-shell Fe/Fe2 O3 nanowires as anodes for high-performance lithium-ion batteries (LIBs) is reported. The nanowires are prepared in a facile synthetic process in aqueous solution under ambient conditions with subsequent annealing treatment that could tune the capacity for lithium storage. When this hybrid is used as an anode material for LIBs, the outer Fe2 O3 shell can act as an electrochemically active material to store and release lithium ions, whereas the highly conductive and inactive Fe core functions as nothing more than an efficient electrical conducting pathway and a remarkable buffer to tolerate volume changes of the electrode materials during the insertion and extraction of lithium ions. The core-shell Fe/Fe2 O3 nanowire maintains an excellent reversible capacity of over 767 mA h g(-1) at 500 mA g(-1) after 200 cycles with a high average Coulombic efficiency of 98.6 %. Even at 2000 mA g(-1) , a stable capacity as high as 538 mA h g(-1) could be obtained. The unique composition and nanostructure of this electrode material contribute to this enhanced electrochemical performance. Due to the ease of large-scale fabrication and superior electrochemical performance, these hybrid nanowires are promising anode materials for the next generation of high-performance LIBs. PMID:27406922

  16. Research Progress in Anode Materials for Lithium Ion Batteries%锂离子电池新型负极材料的研究进展

    Institute of Scientific and Technical Information of China (English)

    刘浪浪; 问娟娟

    2014-01-01

    锂离子电池作为一种电源应用很广泛,但是在应用中存在一些不足,选取电化学性能良好的正负极材料是提高和改善锂离子电池电化学性能最重要的因素。从新型碳材料、硅基负极材料、锡基负极材料三方面介绍了目前锂离子电池的研究状况,并展望了锂离子电池负极材料的发展趋势。%Lithium ion battery as a power is widely used, but there are some deficiencies in the application. Selection of electrode materials with excellent electrochemical performances is the key factor to enhance and improve the electrochemical performance of the lithium ion battery. In this paper, the current research situation of lithium ion batteries were introduced from the aspects of new carbon materials, silicon-based anode materials and tin-based anode materials, and the development trend of the anode materials for lithium ion battery was prospected.

  17. Si-Based Materials as the Anode of Lithium-Ion Batteries%锂离子电池负极硅基材料

    Institute of Scientific and Technical Information of China (English)

    陶占良; 王洪波; 陈军

    2011-01-01

    硅基材料由于其高电化学容量是一种非常有发展前途的锂离子电池负极材料,但其在充放电过程中体积变化大、循环寿命差、首次库仑效率低等是阻碍其商业化的主要问题.本文综述了硅在脱嵌锂时晶体结构及表/界面的变化,以及改善其电化学性能方面的研究进展,并阐述其作为锂离子电池负极材料的研究前景.%Silicon-based materials are promising anode materials for lithium-ion batteries (LIBs) due to their high-energy capacity. However, the commercialization of silicon-based materials as the anode of LIBs has been hindered by the huge volume change, poor cycle life and low initial coulombic efficiency during the charge/discharge process. This article reviews the change of both the crystal structure and the surface/interface of Si-based material during the interealation/deintercalation of lithium, and the methods improving the electrochemical performance. In addition, the prospects of silicon-based materials as the anode of LIBs are also discussed.

  18. MoO2-loaded porous carbon hollow spheres as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    In this study, novel MoO2-loaded porous carbon hollow sphere composite materials were synthesized. The composites consisted of homogeneous hollow microspheres with a size of ∼0.7 ± 0.1 μm and a shell thickness of ∼70 nm; MoO2 nanoparticles with an average size of ∼12 nm were uniformly dispersed in the shells of the porous carbon hollow spheres (PCHS). The MoO2/PCHS composites showed high capacity and excellent capacity retention when they were applied as an anode material for Li ion batteries. The composite containing 44.2% of MoO2 revealed a reversible capacity of 574 mAh g−1 at a current density of 50 mA g−1, and a first coulombic efficiency of 61%. After 80 cycles, this composite still retained a capacity of 640 mAh g−1. The good electrochemical performance could be due to the fact that the MoO2 nanoparticles were homogeneously embedded in the shells of the porous carbon hollow spheres in the composites, which effectively prevented volume change or aggregation of the MoO2 nanoparticles during the lithium ion insertion/extraction process. The porous carbon hollow spheres with good electronic conductivity and high surface area offered a large electrode/electrolyte contact area, and a short path length for the Li+ transport. - Highlights: • MoO2-loaded porous carbon hollow sphere composite materials were synthesized. • MoO2 particles are homogeneously embedded in the shells of hollow carbon spheres. • The composite with 44.2% of MoO2 exhibits a capacity of 574 mAh g−1 at 50 mA g−1. • After 80 cycles it has a reversible capacity of 640 mAh g−1

  19. Synthesis of Nanocobalt Powders for an Anode Material of Lithium-Ion Batteries by Chemical Reduction and Carbon Coating

    Directory of Open Access Journals (Sweden)

    Seong-Hyeon Hong

    2014-01-01

    Full Text Available Nanosized Co powders were prepared by a chemical reduction method with and without CTAB (cetyltrimethylammonium bromide, C19H42BrN and carbon-coating heat treatment at 700°C for 1 h, and the electrochemical properties of the prepared nanosized Co powders were examined to evaluate their suitability as an anode material of Li-ion batteries. Nanosized amorphous Co-based powders could be synthesized by a chemical reduction method in which a reducing agent is added to a Co ion-dissolved aqueous solution. When the prepared nanosized Co-based powders were subjected to carbon-coating heat treatment at 700°C for 1 h, the amorphous phase was crystallized, and a Co single phase could be obtained. The Co-based powder prepared by chemical reduction with CTAB and carbon-coating heat treatment had a smaller first discharge capacity (about 557 mAh/g than the Co-based powder prepared by chemical reduction without CTAB and carbon-coating heat treatment (about 628 mAh/g. However, the former had a better cycling performance than the latter from the third cycle. The carbon-coated layers are believed to have led to quite good cycling performances of the prepared Co-based powders from the third cycle.

  20. Enhancement of electrochemical performance with Zn-Al-Bi layered hydrotalcites as anode material for Zn/Ni secondary battery

    International Nuclear Information System (INIS)

    Bi-doped Zn-Al layered double hydroxides (Zn-Al-Bi LDH) are prepared by the constant pH hydrothermal method and proposed as a novel anodic material in Zn/Ni secondary cells. The Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) images reveal that the as-prepared samples are well-crystallized and hexagon layer structure. The electrochemical performances of the Zn-Al-Bi LDH were analyzed by cyclic voltammetry, tafel plot, electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge tests. Compared with Zn-Al LDH, Zn-Al-Bi LDH with different Zn/Al/Bi molar rations, especially the sample of Zn/Al/Bi = 3:0.8:0.2 (molar ration) have higher discharge capacity and more stable cycling performances. Cyclic voltammograms clearly illuminated that the Zn-Al-Bi LDHs could decrease polarization, maintain the electrochemical activity, and enhance the discharge capacity of Zn-Al LDH. This battery can undergo at least 800 charge-discharge cycles at constant current of 1C without dendrite and short circuits. The discharge capacity of Zn-Al-Bi LDH after the 800th cycle remains about 380 mAh g−1 and the hexagonal crystal structure have no much changed after cycles

  1. Synthesis of amorphous ZnSnO3-C hollow microcubes as advanced anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Amorphous ZnSnO3-C hollow microcubes were prepared for the first time. • ZnSnO3-C hollow microcubes exhibit greatly enhanced lithium storage properties. • The reason for the superior electrochemical properties is proposed. - Abstract: Amorphous ZnSnO3-C hollow microcubes have been produced by calcination of the pre-synthesized ZnSn(OH)6 hollow microcubes in argon, followed by the surface decoration of carbon. The calcination temperature plays an important role in the phase and morphology of the obtained products. ZnSnO3-C hollow microcubes have an average edge length of about 1.0 μm with the shell thickness of approximate 145 nm. When adopted as the anode materials for lithium ion batteries, amorphous ZnSnO3-C hollow microcubes manifest greatly enhanced electrochemical properties compared to amorphous ZnSnO3 hollow and solid counterparts. After 50th cycles, a high reversible capacity of 703 mA h g−1 can be obtained for amorphous ZnSnO3-C hollow microcubes at the current density of 100 mA g−1. The superior lithium storage properties of ZnSnO3-C are due to its unique hollow structure with large specific surface area, the modification of carbon and the amorphous characteristic

  2. AB5-type Hydrogen Storage Alloy Modified with Ti/Zr Used as Anodic Materials in Borohydride Fuel Cell

    Institute of Scientific and Technical Information of China (English)

    Lianbang WANG; Chunan MA; Xinbiao MAO; Yuanming SUN; Seijiro SUDA

    2005-01-01

    Fuel cell using borohydride as the fuel has received much attention. AB5-type hydrogen storage alloy used as the anodic material instead of noble metals has been investigated. In order to restrain the generation of hydrogen and enhance the utilization of borohydride, Ti/Zr metal powders has been added into the parent LmNi4.78Mn0.22 (where Lm is La-richened mischmetal) alloy (LNM) by ball milling and heat treatment methods. It is found that the addition of Ti/Zr metal powders lowers the electrochemical catalytic activity of the electrodes, at the same time, restrains the generation of hydrogen and enhances the utilization of the fuel. All the results show that the hydrogen generation rate or the utilization of the fuel is directly relative to the electrochemical catalytic activity or the discharge capability of the electrodes. The utilization of the fuel increases with discharge current density. It is very important to find a balance between the discharge capability and the utilization of the fuel.

  3. Micro-sized and Nano-sized Fe3O4 Particles as Anode Materials for Lithium-ion Batteries

    Institute of Scientific and Technical Information of China (English)

    Y.X.Chen; L.H.He; P.J.Shang; Q.L.Tang; Z.Q.Liu; H.B.Liu; L.P.Zhou

    2011-01-01

    Micro-sized (1030.3±178.4 nm) and nano-sized (50.4±8.0 nm) Fe3O4 particles have been fabricated through hydrogen thermal reduction of α-Fe2O3 particles synthesized by means of a hydrothermal process. The morphology and microstructure of the micro-sized and the nano-sized Fe3O4 particles were characterized by X-ray diffraction, field-emission gun scanning electron microscopy, transmission electron microscopy and highresolution electron microscopy. The micro-sized Fe3O4 particles exhibit porous structure, while the nano-sized Fe3O4 particles are solid structure. Their electrochemical performance was also evaluated. The nano-sized solid Fe3O4 particles exhibit gradual capacity fading with initial discharge capacity of 1083.1 mAhg-1 and reversible capacity retention of 32.6% over 50 cycles. Interestingly, the micro-sized porous Fe3O4 particles display very stable capacity-cycling behavior, with initial discharge capacity of 887.5 mAhg-1 and charge capacity of 684.4 mAhg-1 at the 50th cycle. Therefore, 77.1% of the reversible capacity can be maintained over 50 cycles. The micro-sized porous Fe3O4 particles with facile synthesis, good cycling performance and high capacity retention are promising candidate as anode materials for high energy-density lithium-ion batteries.

  4. Hollow reduced graphene oxide microspheres as a high-performance anode material for Li-ion batteries

    International Nuclear Information System (INIS)

    Hollow reduced graphene oxide (RGO) microspheres are successfully synthesized in large quantities through spray-drying suspension of graphene oxide (GO) nanosheets and subsequent carbothermal reduction. With this new procedure, blighted-microspherical GO precursor is synthesized through the process of spray drying, afterwards the GO precursor is subsequently calcined at 800 °C for 5 h to obtain hollow RGO microspheres. A series of analyses, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectroscopy (FTIR) are performed to characterize the structure and morphology of intermediates and as-obtained product. The as-obtained hollow RGO microspheres provide a high specific surface area (175.5 m2 g−1) and excellent electronic conductivity (6.3 S cm−1), and facilitated high electrochemical performance as anode material for Li-ion batteries (LIBs). Compared with the RGO nanosheets, the as-obtained hollow RGO microspheres exhibit superior specific capacity and outstanding cyclability. In addition, this spray drying and carbothermal reduction (SDCTR) method provided a facile route to prepare hollow RGO microspheres in large quantities

  5. Nano-structured composite of Si/(S-doped-carbon nanowire network) as anode material for lithium-ion batteries

    Science.gov (United States)

    Shao, Dan; Tang, Daoping; Yang, Jianwen; Li, Yanwei; Zhang, Lingzhi

    2015-11-01

    Novel nanostructured silicon composites, Si/Poly(3,4-ethylenedioxythiophene) nanowire network (Si/PNW) and Si/(S-doped-carbon nanowire network) (Si/S-CNW), are prepared by a soft-template polymerization of 3,4-ethylenedioxythiophene (EDOT) using sodium dodecyl sulfate (SDS) as surfactant with the presence of Si nanoparticles and a subsequent carbonization of Si/PNW, respectively. The presence of Si nanoparticles in the soft-template polymerization of EDOT plays a critical role in the formation of PEDOT nanowire network instead of 1D nanowire. After the carbonization of PEDOT, the S-doped-carbon nanowire network matrix shows higher electrical conductivity than PNW counterpart, which facilitates to construct robust conductive bridges between Si nanoparticles and provide large electrode/electrolyte interfaces for rapid charge transfer reactions. Thus, Si/S-CNW composite exhibits excellent cycling stability and rate capability as anode material, retaining a specific capacity of 820 mAh g-1 after 400 cycles with a very small capacity fade of 0.09% per cycle.

  6. Aerosol assisted synthesis of hierarchical tin–carbon composites and their application as lithium battery anode materials

    KAUST Repository

    Guo, Juchen

    2013-01-01

    We report a method for synthesizing hierarchically structured tin-carbon (Sn-C) composites via aerosol spray pyrolysis. In this method, an aqueous precursor solution containing tin(ii) chloride and sucrose is atomized, and the resultant aerosol droplets carried by an inert gas are pyrolyzed in a high-temperature tubular furnace. Owing to the unique combination of high reaction temperature and short reaction time, this method is able to achieve a hetero-structure in which small Sn particles (15 nm) are uniformly embedded in a secondary carbon particle. This procedure allows the size and size distribution of the primary Sn particles to be tuned, as well as control over the size of the secondary carbon particles by addition of polymeric surfactant in the precursor solution. When evaluated as anode materials for lithium-ion batteries, the resultant Sn-C composites demonstrate attractive electrochemical performance in terms of overall capacity, electrochemical stability, and coulombic efficiency. © 2013 The Royal Society of Chemistry.

  7. Synthesis and Characterization of Silicon Nanoparticles Inserted into Graphene Sheets as High Performance Anode Material for Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Yong Chen

    2014-01-01

    Full Text Available Silicon nanoparticles have been successfully inserted into graphene sheets via a novel method combining freeze-drying and thermal reduction. The structure, electrochemical performance, and cycling stability of this anode material were characterized by SEM, X-ray diffraction (XRD, charge/discharge cycling, and cyclic voltammetry (CV. CV showed that the Si/graphene nanocomposite exhibits remarkably enhanced cycling performance and rate performance compared with bare Si nanoparticles for lithium ion batteries. XRD and SEM showed that silicon nanoparticles inserted into graphene sheets were homogeneous and had better layered structure than the bare silicon nanoparticles. Graphene sheets improved high rate discharge capacity and long cycle-life performance. The initial capacity of the Si nanoparticles/graphene keeps above 850 mAhg−1 after 100 cycles at a rate of 100 mAg−1. The excellent cycle performances are caused by the good structure of the composites, which ensured uniform electronic conducting sheet and intensified the cohesion force of binder and collector, respectively.

  8. Preparation and electrochemical performances of cubic shape Cu2O as anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Cubic and star-shaped crystalline Cu2O particles were synthesized by reducing the copper citrate complex solution with glucose. The microstructure and morphology of the Cu2O were characterized by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical properties of the Cu2O as anode materials for lithium ion batteries were measured by galvanostatic charge-discharge tests. The as-synthesized Cu2O particles were 1-2 μm with narrow distribution and the shape of Cu2O particles had an effect on the electrochemical properties. The cubic Cu2O particles delivered a higher reversible discharge capacity (390 mAh g-1) than the star-shaped Cu2O, and also exhibited good cyclability. The star-shaped Cu2O particles presented poor cyclability due to pulverization and deterioration after cycling, but the morphology of the cubic Cu2O particles was stable even after 50 cycles

  9. Ultrafine Nb2O5 Nanocrystal Coating on Reduced Graphene Oxide as Anode Material for High Performance Sodium Ion Battery.

    Science.gov (United States)

    Yan, Litao; Chen, Gen; Sarker, Swagotom; Richins, Stephanie; Wang, Huiqiang; Xu, Weichuan; Rui, Xianhong; Luo, Hongmei

    2016-08-31

    Ultrafine niobium oxide nanocrystals/reduced graphene oxide (Nb2O5 NCs/rGO) was demonstrated as a promising anode material for sodium ion battery with high rate performance and high cycle durability. Nb2O5 NCs/rGO was synthesized by controllable hydrolysis of niobium ethoxide and followed by heat treatment at 450 °C in flowing forming gas. Transmission electron microscopy images showed that Nb2O5 NCs with average particle size of 3 nm were uniformly deposited on rGO sheets and voids among Nb2O5 NCs existed. The architecture of ultrafine Nb2O5 NCs anchored on a highly conductive rGO network can not only enhance charge transfer and buffer the volume change during sodiation/desodiation process but also provide more active surface area for sodium ion storage, resulting in superior rate and cycle performance. Ex situ XPS analysis revealed that the sodium ion storage mechanism in Nb2O5 could be accompanied by Nb(5+)/Nb(4+) redox reaction and the ultrafine Nb2O5 NCs provide more surface area to accomplish the redox reaction. PMID:27508452

  10. Micro- and nanomorphology coexisting in titanium dioxide coating for application as anode material in secondary lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Wen-Chi, E-mail: wenchilo694@gmail.com; Chu, Hou-Jen; He, Ju-Liang

    2015-03-31

    Titanium dioxide has recently attracted attention as an anode material for use in lithium-ion batteries, owing to its high reversible capacity and durable charge/discharge characteristics. The aim of the study is to combine micro-arc oxidation (MAO) and post-alkali treatment to realize an anatase titanium dioxide (TiO{sub 2}) scaffold layer on titanium plates. Using this combination, coexisting micro- and nanomorphology can be realized in the TiO{sub 2} layer. This increases the specific surface area of the TiO{sub 2} layer and thereby improves the charge capacity and charge/discharge rate of the anode. The effectiveness of MAO to fabricate a micrometer-scale porous TiO{sub 2} structure on titanium plate, and the formation of nano-flakes by alkali treatment on porous anatase TiO{sub 2} layer was demonstrated. Further, numerous 40–80 nm alkali-treatment-induced nano-flakes grew all over the oxide surface, substantially increasing its specific surface area. The measured electrochemical properties demonstrate that at potentials of − 1.98 V and − 0.56 V vs. Ag/AgCl, lithium ions were respectively inserted into and extracted from the TiO{sub 2} layer with nano-flakes. The nano-flakes promote faster lithium-ion insertion and extraction and higher associated number of charge than the MAO TiO{sub 2}. The detailed charging/discharging kinetic processes of the MAO, annealed MAO, alkali-treated MAO, and annealed and alkali-treated MAO specimens were determined using electrochemical impedance spectroscopy, thus providing further insight into the performance of the TiO{sub 2} coating. - Highlights: • A micrometer-scale porous crystalline TiO{sub 2} layer was fabricated by MAO. • After alkali treatment, the oxide surface exhibits numerous pores. • The layer was composed of predominantly anatase and minor rutile. • Optimum solution temperature and NaOH concentration yielded nano-flaky morphology. • Such morphology leads to the increase performance of the treated

  11. Micro- and nanomorphology coexisting in titanium dioxide coating for application as anode material in secondary lithium-ion batteries

    International Nuclear Information System (INIS)

    Titanium dioxide has recently attracted attention as an anode material for use in lithium-ion batteries, owing to its high reversible capacity and durable charge/discharge characteristics. The aim of the study is to combine micro-arc oxidation (MAO) and post-alkali treatment to realize an anatase titanium dioxide (TiO2) scaffold layer on titanium plates. Using this combination, coexisting micro- and nanomorphology can be realized in the TiO2 layer. This increases the specific surface area of the TiO2 layer and thereby improves the charge capacity and charge/discharge rate of the anode. The effectiveness of MAO to fabricate a micrometer-scale porous TiO2 structure on titanium plate, and the formation of nano-flakes by alkali treatment on porous anatase TiO2 layer was demonstrated. Further, numerous 40–80 nm alkali-treatment-induced nano-flakes grew all over the oxide surface, substantially increasing its specific surface area. The measured electrochemical properties demonstrate that at potentials of − 1.98 V and − 0.56 V vs. Ag/AgCl, lithium ions were respectively inserted into and extracted from the TiO2 layer with nano-flakes. The nano-flakes promote faster lithium-ion insertion and extraction and higher associated number of charge than the MAO TiO2. The detailed charging/discharging kinetic processes of the MAO, annealed MAO, alkali-treated MAO, and annealed and alkali-treated MAO specimens were determined using electrochemical impedance spectroscopy, thus providing further insight into the performance of the TiO2 coating. - Highlights: • A micrometer-scale porous crystalline TiO2 layer was fabricated by MAO. • After alkali treatment, the oxide surface exhibits numerous pores. • The layer was composed of predominantly anatase and minor rutile. • Optimum solution temperature and NaOH concentration yielded nano-flaky morphology. • Such morphology leads to the increase performance of the treated Ti plate

  12. Relationship between anode material, supporting electrolyte and current density during electrochemical degradation of organic compounds in water

    Energy Technology Data Exchange (ETDEWEB)

    Guzmán-Duque, Fernando L. [Grupo de diagnóstico y control de la contaminación, Facultad de ingeniería, Universidad de Antioquia, A.A. 1226, Medellín (Colombia); Palma-Goyes, Ricardo E. [Grupo de Investigación en Remediación Ambiental y Biocatálisis, Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquía Udea, A.A. 1226, Medellín (Colombia); González, Ignacio [Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Química, Av. San Rafael Atlixco No 186, C.P 09340, México D.F (Mexico); Peñuela, Gustavo [Grupo de diagnóstico y control de la contaminación, Facultad de ingeniería, Universidad de Antioquia, A.A. 1226, Medellín (Colombia); Torres-Palma, Ricardo A., E-mail: rtorres@matematicas.udea.edu.co [Grupo de Investigación en Remediación Ambiental y Biocatálisis, Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquía Udea, A.A. 1226, Medellín (Colombia)

    2014-08-15

    Highlights: • Pathway and efficiency are linked to the current-electrode–electrolyte interaction. • Unlike BDD, IrO{sub 2} route was independent of current but dependent on the electrolyte. • IrO{sub 2}/SO{sub 4}{sup 2−} and IrO{sub 2}/Cl{sup −} routes were via IrO{sub 3} and chlorine species, respectively. • BDD/SO{sub 4}{sup 2−} and IrO{sub 2}/Cl{sup −} systems were favored at low and high currents, respectively. - Abstract: Taking crystal violet (CV) dye as pollutant model, the electrode, electrolyte and current density (i) relationship for electro-degrading organic molecules is discussed. Boron-doped diamond (BDD) or Iridium dioxide (IrO{sub 2}) used as anode materials were tested with Na{sub 2}SO{sub 4} or NaCl as electrolytes. CV degradation and generated oxidants showed that degradation pathways and efficiency are strongly linked to the current density-electrode–electrolyte interaction. With BDD, the degradation pathway depends on i: If i < the limiting current density (i{sub lim}), CV is mainly degraded by ·OH radicals, whereas if i > i{sub lim}, generated oxidants play a major role in the CV elimination. When IrO{sub 2} was used, CV removal was not dependent on i, but on the electrolyte. Pollutant degradation in Na{sub 2}SO{sub 4} on IrO{sub 2} seems to occur via IrO{sub 3}; however, in the presence of NaCl, degradation was dependent on the chlorinated oxidative species generated. In terms of efficiency, the Na{sub 2}SO{sub 4} electrolyte showed better results than NaCl when BDD anodes were employed. On the contrary, NaCl was superior when combined with IrO{sub 2}. Thus, the IrO{sub 2}/Cl{sup −} and BDD/SO{sub 4}{sup 2−} systems were better at removing the pollutant, being the former the most effective. On the other hand, pollutant degradation with the BDD/SO{sub 4}{sup 2−} and IrO{sub 2}/Cl{sup −} systems is favored at low and high current densities, respectively.

  13. Relationship between anode material, supporting electrolyte and current density during electrochemical degradation of organic compounds in water

    International Nuclear Information System (INIS)

    Highlights: • Pathway and efficiency are linked to the current-electrode–electrolyte interaction. • Unlike BDD, IrO2 route was independent of current but dependent on the electrolyte. • IrO2/SO42− and IrO2/Cl− routes were via IrO3 and chlorine species, respectively. • BDD/SO42− and IrO2/Cl− systems were favored at low and high currents, respectively. - Abstract: Taking crystal violet (CV) dye as pollutant model, the electrode, electrolyte and current density (i) relationship for electro-degrading organic molecules is discussed. Boron-doped diamond (BDD) or Iridium dioxide (IrO2) used as anode materials were tested with Na2SO4 or NaCl as electrolytes. CV degradation and generated oxidants showed that degradation pathways and efficiency are strongly linked to the current density-electrode–electrolyte interaction. With BDD, the degradation pathway depends on i: If i < the limiting current density (ilim), CV is mainly degraded by ·OH radicals, whereas if i > ilim, generated oxidants play a major role in the CV elimination. When IrO2 was used, CV removal was not dependent on i, but on the electrolyte. Pollutant degradation in Na2SO4 on IrO2 seems to occur via IrO3; however, in the presence of NaCl, degradation was dependent on the chlorinated oxidative species generated. In terms of efficiency, the Na2SO4 electrolyte showed better results than NaCl when BDD anodes were employed. On the contrary, NaCl was superior when combined with IrO2. Thus, the IrO2/Cl− and BDD/SO42− systems were better at removing the pollutant, being the former the most effective. On the other hand, pollutant degradation with the BDD/SO42− and IrO2/Cl− systems is favored at low and high current densities, respectively

  14. Electrochemical properties of Si/(FeSiB) anode materials prepared by high-energy mechanical milling

    International Nuclear Information System (INIS)

    Highlights: • Si-embedded in less-active FeSiB nano-composite structures synthesized. • Capacity of Si anode is 540 mAh g−1 and 533 mAh g−1 after the 3rd and 50th cycle. • The nano-composite exhibited 99% efficiency until the 50th cycle. • Cracks or voids in coin cells are rarely observed during cycling. • Elastic recoverable energy range of FeSiB is 2.96 times higher than Si. -- Abstract: Nano-structured composite with overall atomic composition Si60/(FeSiB)40 has been synthesized by high-energy mechanical milling (HEMM) for Lithium-ion rechargeable batteries as anode material. Crystal structure, microstructure, electrochemical properties, elastic modulus and Vickers hardness (HV) have been observed by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HR-TEM), electrochemical test and nano-indentation test. With increasing milling time from 6 to 10 h, we observed a relatively homogeneous structure comprised of nano-crystalline active silicon (Si) embedded in less active FeSiB matrix phase. Electrochemical properties of 10 h milled nano-composite powder offers low capacity fade, high coulombic efficiency from 3rd cycle (540 mAh g−1) to until 102nd cycle (495 mAh g−1). The coulombic efficiencies of both 6 and 10 h milled powders are 98% and 99%, respectively. Coin cell cross sections of 6 and 10 h milled powders showed evidence for the void formation during lithiation and delithiation. Nano-indentation results exhibited that the amorphous FeSiB flakes have 2.96 times higher recoverable energy than Si. Resultant composite powders showed high irreversible capacity and stable lithiation and delithiation due to the reduced particle size, increased surface area and the highly elastic FeSiB matrix phase. Research reveals that the obtained nano-composite can be a promising candidate for lithium-ion rechargeable batteries

  15. CoSb3-graphite composite anode material for lithium ion batteries

    Institute of Scientific and Technical Information of China (English)

    XIE Jian; CAO Gaoshao; ZHAO Xinbing

    2005-01-01

    The CoSb3-graphite composite was prepared by ball-milling. The electrochemical performance of the composite material was evaluated using the lithium ion model cell Li / LiPF6 (EC + DMC) / CoSb3C4. It was found that the CoSb3C4 composite shows higher reversible capacity than the pure CoSb3 alloy, and its first reversible (Li-ions removal) capacity reaches 721 Ma·h·g-1, which exceeds the theoretical capacity (550 Ma.h.g-1) of CoSb3C4.

  16. Process and electrolyte for applying barrier layer anodic coatings

    International Nuclear Information System (INIS)

    Various metals may be anodized, and preferably barrier anodized, by anodizing the metal in an electrolyte comprising quaternary ammonium compound having a complex metal anion in a solvent containing water and a polar, water soluble organic material. (U.S.)

  17. Sn-Co-artificial graphite composite as anode material for rechargeable lithium batteries

    International Nuclear Information System (INIS)

    Nanosized Sn-Co prepared by ultrasonic-assisted chemical reduction is milled with artificial graphite (AG) to form Sn-Co-AG composite. The as-prepared materials are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectrometry and Brunauer-Emmett-Telle (BET) surface area measurement. XRD patterns show that Sn-Co particles are poorly crystallized and artificial graphite has a typical hexagonal graphite structure phase. The diffraction peaks of Sn-Co particles remain the same but some of AG obviously change after milling Sn-Co with AG. BET areas of AG, Sn-Co and Sn-Co-AG are 1.569, 13.187 and 6.754 m2 g-1, respectively. SEM images display the as-prepared Sn-Co particles have a size distribution ranging from 20 to 70 nm in diameter. After milling Sn-Co with AG, Sn-Co particles keep similar morphology but there is a perceptible change in AG. Electrochemical tests show that Sn-Co-AG composite possesses much improved electrochemical performance than the state-of-the-art graphite. This composite has great potential as an alternative material for improving the energy density of a lithium ion secondary battery.

  18. SnSe/carbon nanocomposite synthesized by high energy ball milling as an anode material for sodium-ion and lithium-ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: A homogeneous nanocomposite of SnSe and carbon black was synthesised by high energy ball milling and empolyed as an anode material for sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs). The nanocomposite anode exhibits excellent electrochemical performances in both SIBs and LIBs. - Highlights: • A homogeneous nanocomposite of SnSe and carbon black was fabricated by high energy ball milling. • SnSe and carbon black are homogeneously mixed at the nanoscale level. • The SnSe/C anode exhibits excellent electrochemical performances in both SIBs and LIBs. - Abstract: A homogeneous nanocomposite of SnSe and carbon black, denoted as SnSe/C nanocomposite, was fabricated by high energy ball milling and empolyed as a high performance anode material for both sodium-ion batteries and lithium-ion batteries. The X-ray diffraction patterns, scanning electron microscopy and transmission electron microscopy observations confirmed that SnSe in SnSe/C nanocomposite was homogeneously distributed within carbon black. The nanocomposite anode exhibited enhanced electrochemical performances including a high capacity, long cycling behavior and good rate performance in both sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs). In SIBs, an initial capacitiy of 748.5 mAh g−1 was obtained and was maintained well on cycling (324.9 mAh g−1 at a high current density of 500 mA g−1 in the 200 th cycle) with 72.5% retention of second cycle capacity (447.7 mAh g−1). In LIBs, high initial capacities of approximately 1097.6 mAh g−1 was obtained, and this reduced to 633.1 mAh g−1 after 100 cycles at 500 mA g−1

  19. 3D Fe{sub 2}(MoO{sub 4}){sub 3} microspheres with nanosheet constituents as high-capacity anode materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Hao; Wang, Shiqiang [Hubei University, Key Laboratory for Synthesis and Applications of Organic Functional Molecules (China); Wang, Jiazhao; Wang, Jun [University of Wollongong, Institute for Superconducting and Electronic Materials (Australia); Li, Lin; Yang, Yun; Feng, Chuanqi, E-mail: cfeng@hubu.edu.cn [Hubei University, Key Laboratory for Synthesis and Applications of Organic Functional Molecules (China); Sun, Ziqi, E-mail: ziqi.sun@qut.edu.au [Queensland University of Technology, School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty (Australia)

    2015-11-15

    Three-dimensional (3D) Fe{sub 2}(MoO{sub 4}){sub 3} microspheres with ultrathin nanosheet constituents are first synthesized as anode materials for the lithium-ion battery. It is interesting that the single-crystalline nanosheets allow rapid electron/ion transport on the inside, and the high porosity ensures fast diffusion of liquid electrolyte in energy storage applications. The electrochemical properties of Fe{sub 2}(MoO{sub 4}){sub 3} as anode demonstrates that 3D Fe{sub 2}(MoO{sub 4}){sub 3} microspheres deliver an initial capacity of 1855 mAh/g at a current density of 100 mA/g. Particularly, when the current density is increased to 800 mA/g, the reversible capacity of Fe{sub 2}(MoO{sub 4}){sub 3} anode still arrived at 456 mAh/g over 50 cycles. The large and reversible capacities and stable charge–discharge cycling performance indicate that Fe{sub 2}(MoO{sub 4}){sub 3} is a promising anode material for lithium battery applications.Graphical abstractThe electrochemical properties of Fe{sub 2}(MoO{sub 4}){sub 3} as anode demonstrates that 3D Fe{sub 2}(MoO{sub 4}){sub 3} microspheres delivered an initial capacity of 1855 mAh/g at a current density of 100 mA/g. When the current density was increased to 800 mA/g, the Fe{sub 2}(MoO{sub 4}){sub 3} still behaved high reversible capacity and good cycle performance.

  20. Mesoporous silicon/carbon hybrids with ordered pore channel retention and tunable carbon incorporated content as high performance anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    In-situ magnesiothermic reduction reaction route was developed to synthesize mesoporous Si/C (silicon/carbon) hybrids with ordered pore channel retention and tunable carbon incorporated content as high performance anode materials for LIBs (lithium ion batteries). The effect of carbon incorporation on the microstructures and electrochemical performance of the Si/C hybrid LIBs anodes is investigated. The incorporation of carbon in the Si/C hybrids not only prevents the ordered structure of mesoporous silicon from collapsing, but also increases the electrical conductivity of the synthesized Si/C hybrids. The as-prepared Si/C hybrid LIBs anode with an optimal carbon content of 7.05 wt%, displays improved electrochemical performance with a high reversible specific capacity, rate capability and excellent cyclic performance, showing a higher specific capacity of up to 1452 mAh g−1 at a current density of 200 mA g−1 after 100 cycles and a high coulombic efficiency of up to 99.2%. The great improvement of the electrochemical performance of the ordered mesoporous Si/C hybrid LIBs anodes can be attributed to the unique ordered structure, large surface area, the homogeneously incorporated carbon in the Si/C hybrids. The synthesized ordered mesoporous Si/C hybrids are promising for potential applications as LIB anode materials with enhanced electrochemical performance. - Highlights: • Ordered mesoporous Si/C hybrids are synthesized by chemically reducing silica. • The pre-impregnated carbon source prevents the ordered structure from collapsing. • Mesoporous Si/C hybrids exhibit excellent Li+ storage capacity and cyclic stability

  1. One-pot synthesis of nitrogen and sulfur co-doped graphene supported MoS2 as high performance anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Nitrogen and sulfur co-doped graphene supported MoS2 nanosheets were successfully prepared and used as anode materials for Li-ion batteries. • The as-prepared anode materials show excellent stability in Li-ion batteries. • The materials show high reversible capacity for lithium ion batteries. - Abstract: Nitrogen and sulfur co-doped graphene supported MoS2 (MoS2/NS-G) nanosheets were prepared through a one-pot thermal annealing method. The as prepared samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Raman spectra and electrochemical techniques. The MoS2/NS-G shows high reversible capacity about 1200 mAh/g at current density of 150 mA/g and excellent stability in Li-ion batteries. It was demonstrated the co-doping of graphene by N and S could significantly enhance the durability of MoS2 as anode materials for Li-ion batteries

  2. Facile synthesis of a MoO2-Mo2C-C composite and its application as favorable anode material for lithium-ion batteries

    Science.gov (United States)

    Zhu, Yanping; Wang, Shaofeng; Zhong, Yijun; Cai, Rui; Li, Li; Shao, Zongping

    2016-03-01

    A composite of MoO2-Mo2C-C is fabricated through a facile ion-exchange route for the first time as an alternative anode material for lithium-ion batteries (LIBs). A macroporous cinnamic anion-exchange resin interacts with ammonium molybdate tetrahydrate in aqueous solution, and the product is then calcined under an inert gas atmosphere. The interaction between the resin and ammonium molybdate tetrahydrate results in an atomic level dispersion of the molybdenum over the organic carbon precursor (resin), while the calcination process allows the formation of MoO2 and Mo2C as well as the pyrolysis of resin to solid carbon. According to field-emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM) measurements, ultrafine MoO2 and Mo2C nanoparticles are uniformly dispersed but firmly attached within an amorphous carbon framework. When evaluated as an anode material, the as-synthesized sample exhibits superior electrochemical performance. The specific discharge capacity is as high as 1491 mA h g-1 in the first cycle and 724 mA h g-1 over 50 cycles at a current density of 0.2 A g-1. This simple, environmentally friendly, low-cost and easily scaled up method, has significant potential for mass industrial production of MoO2-based material as next-generation anode material of LIBs with wide application capability.

  3. Vanadium nitride as a novel thin film anode material for rechargeable lithium batteries

    International Nuclear Information System (INIS)

    Vanadium mononitride (VN) thin films have been successfully fabricated by magnetron sputtering. Its electrochemical behaviour with lithium was examined by galvanostatic cell cycling and cyclic voltammetry. The capacity of VN was found to be stable above 800 mAh g-1 after 50 cycles. By using ex situ X-ray diffraction, high-resolution transmission electron microscopy and selected area electron diffraction as well as in situ spectroelectrochemical measurements, the electrochemical reaction mechanism of VN with lithium was investigated. The reversible conversion reaction of VN into metal V and Li3N was revealed. The high reversible capacity and good stable cycle of VN thin film electrode made it a new promising lithium-ion storage material for future rechargeable lithium batteries

  4. Nanostructured WO3 thin film as a new anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Nanostructured WO3 thin film has been successfully fabricated by radio-frequency magnetron sputtering method and its electrochemistry with lithium was investigated for the first time. The reversible discharge capacity of WO3/Li cells cycled between 0.01 V and 4.0 V was found above 626 mAh/g during the first 60 cycles at the current density 0.02 mA/cm2. By using X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and selected-area electron diffraction measurements, the reversible conversion of WO3 into nanosized metal W and Li2O was revealed. The high reversible capacity and good recyclability of WO3 electrode made it become a promising cathode material for future rechargeable lithium batteries.

  5. Low voltage cathodic protection for high strength steels. Part 1: Definition of a new aluminum galvanic anode material

    Energy Technology Data Exchange (ETDEWEB)

    Pautasso, J.P. [Ministry of Defense, Paris (France); Le Guyader, H.; Debout, V. [Direction des Constructions Navales Cherbourg (France)

    1998-12-31

    Zn or Al-Zn-In sacrificial anodes are commonly used to protect submerged marine structures from general corrosion and galvanic corrosion. However, such electronegative alloys can also induce stress corrosion cracking or hydrogen embrittlement on high strength steels. Decreasing the electronegative potential applied to the structure, in the suitable range (around {minus}0.80 V vs Ag/AgCl) can significantly reduce the amount of hydrogen produced by the cathodic reaction and thus limit the risk of hydrogen embrittlement. The present work has consisted in determining the criteria for a new cathodic protection system with low voltage anodes and selecting one anode that matches the determined requirements, on the basis of laboratory tests. Among the various alloys tested the Al-O.1% Ga anode provided the most promising results and therefore was selected. The first full scale marine tests performed on an industrial casting of this anode have shown the effectiveness of the Al-O.1% Ga anode in the chosen potential range, with a satisfactory galvanic efficiency in real environments.

  6. A new strategy for synthesis of lithium zinc titanate as an anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Li2ZnTi3O8 has been firstly synthesized via a molten-salt method. • Li2ZnTi3O8 can be synthesized by sintering for only 1 h via molten-salt method. • Li2ZnTi3O8 delivers large specific capacities. - Abstract: Lithium zinc titanate (Li2ZnTi3O8) anode materials have been firstly synthesized via a molten-salt method using 0.38LiOH·H2O–0.62LiNO3 as eutectic molten salts. The effects of sintering temperature and sintering time on the structures and physicochemical properties of the Li2ZnTi3O8 materials are also studied in detail. It is found that Li2ZnTi3O8 obtained by sintering at 700 °C for 3 h exhibits a typical cubic spinel structure with P4332 space group. Nano-sized particles are presented and the particles are homogeneous for the Li2ZnTi3O8 prepared by sintering at 700 °C for 3 h. Electrochemical tests demonstrate that the sample possesses large capacities. The largest capacities of 167.8 and 142.4 mAh g−1 are delivered at 2 and 3 A g−1, respectively. 137.8 and 113.3 mAh g−1 are kept for the sample at the 100th cycle at the two current densities, respectively. The large discharge specific capacities may be attributed to the good crystallinity, small particle size and low charge-transfer resistance of Li2ZnTi3O8

  7. Preparation and characterization of spinel Li4Ti5O12 anode material from industrial titanyl sulfate solution

    International Nuclear Information System (INIS)

    Research highlights: → Spine Li4Ti5O12 can be synthesized from the low cost industrial titanyl sulfate solution and shows excellent electrochemical performance. → In this study, we introduce the adverse impact of sulphur on the electrochemical performance of Li4Ti5O12. → This method is a short, simple, efficient, useful, economical and environment-friendly way for both industrial titanyl sulfate utilization and materials preparation. - Abstract: Spinel Li4Ti5O12 anode material is successfully synthesized by a solid-state method using lithium carbonate and titanium precursors which are prepared by the low cost industrial titanyl sulfate solution. The characters of H2TiO3 and TiO2 precursors are determined by TG/DTA and SEM methods. TG-DAT and EDS methods show that H2TiO3 can absorb sulphate ions which can be present as impurities. XRD method shows that the impure phases of Li2SO4 and rutile TiO2 appear in Li4Ti5O12 synthesized by H2TiO3. The formation of Li2SO4 is identified in thermodynamics during the process of calcination. Owing to the formation of Li2SO4 impurity, the capacity of the Li4Ti5O12 synthesized by H2TiO3 is low. One effective way that can tackle this problem is to remove the sulphur by calcining H2TiO3, after calcinations, the production will have a thermal treatment with Li2CO3. The obtained Li4Ti5O12 shows better electrochemical performance. The specific capacities can be increased by 20 mAh g-1 at 0.1, 0.5 and 1C rates.

  8. Multi-walled carbon nanotube-reinforced porous iron oxide as a superior anode material for lithium ion battery

    International Nuclear Information System (INIS)

    Highlights: • Electrochemical performance of Fe3O4 is improved by combining different approaches. • Porous Cu substrate is used to enlarge surface area and improve conductivity. • MWCNT is used to reinforce the electrode structure and change morphology of Fe3O4. • Reversible capacity, capacity retention and high-rate performance are improved. - Abstract: Multi-walled carbon nanotube-reinforced porous iron oxide (Fe3O4/MWCNT) is synthesized by a two-step approach with porous Cu substrate serving as current collector. Porous Cu substrate is prepared through electroless deposition with hydrogen bubble serving as template. Fe3O4/MWCNT composites are prepared by the electrodeposition of Fe3O4 in the presence of dispersed MWCNTs from a Fe2(SO4)3 solution with MWCNT suspension. Results showed that Fe3O4 forms granular nanoparticles on the porous Cu substrate with several MWCNTs embedded in it. Adding MWCNTs changes the morphology of Fe3O4. Smooth Fe3O4, smooth Fe3O4/MWCNT, and porous Fe3O4 composites are also prepared for comparison. When used as anode materials, porous Fe3O4/MWCNT composites have a reversible capacity of approximately 601 mA h g−1 at the 60th cycle at a cycling rate of 100 mA g−1. This value is higher than that of the other materials. The reversible capacity at a cycling rate of 10,000 mA g−1 is approximately 50% of that at 100 mA g−1. Therefore, the MWCNT-reinforced porous Fe3O4 composite exhibits much better reversible capacity, capacity retention, and high-rate performance than the other samples. This finding can be ascribed to the porous structure of Fe3O4, better conductivity of porous Cu substrate and MWCNTs, and the morphology change of Fe3O4 nanoparticles upon the addition of MWCNTs

  9. A nanocomposite of MoO3 coated with PPy as an anode material for aqueous sodium rechargeable batteries with excellent electrochemical performance

    International Nuclear Information System (INIS)

    A nanocomposite of molybdenum trioxide (MoO3) nanobelts coated with polypyrrole was prepared as an anode material for aqueous rechargeable sodium batteries (ARSBs). When nanowire Na0.35MnO2 is used as the cathode, the ARSB can deliver an energy density of 20 Wh kg−1 at 80 W kg−1 and even maintain 18 Wh kg−1 at 2.6 kW kg−1 in 0.5 mol L−1 Na2SO4 aqueous electrolyte, suggesting a good rate capability that can be comparable with supercapacitors. In addition, its cycling behavior is greatly improved compared with the virginal MoO3. This will provide a new direction to explore non-carbon anode materials for ARSBs with excellent electrochemical performance. This good performance exhibits that this battery will be a promising candidate for the storage of solar and wind energies

  10. Hybrid CuO/SnO2 nanocomposites: Towards cost-effective and high performance binder free lithium ion batteries anode materials

    International Nuclear Information System (INIS)

    Hybrid CuO/SnO2 nanocomposites are synthesized by a facile thermal annealing method on Cu foils. Compared to pristine CuO and SnO2 nanostructures, hybrid CuO/SnO2 nanocomposites exhibit the enhanced electrochemical performances as the anode material of lithium ion batteries (LIBs) with high specific capacity and excellent rate capability. The binder free CuO/SnO2 nanocomposites deliver a specific capacity of 718 mA h g−1 at a current density of 500 mA g−1 even after 200 cycles. The enhanced electrochemical performances are attributed to the synergistic effect between SnO2 nanoparticles and CuO nanoarchitectures. Such hybrid CuO/SnO2 nanocomposites could open up a new route for the development of next-generation high-performance and cost-effective binder free anode material of LIBs for mass production.

  11. Effects of TiO2 crystal structure on the performance of Li4Ti5O12 anode material

    International Nuclear Information System (INIS)

    Highlights: ► The reactivity of TiO2 with Li2CO3 gradually decreases as the TiO2 crystal structure changes. ► The specific capacity of Li4Ti5O12 decreases obviously with the TiO2 crystal structure changing. ► The TiO2 crystal structure has not large effects on the cycling performance of Li4Ti5O12 material. ► The reaction of TiO2 with Li2CO3 is an exothermic behavior. - Abstract: Li4Ti5O12 anode material is synthesized using TiO2 with different crystal structure as titanium source by solid-state method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical test methods are applied to characterize the effects of TiO2 crystal structure on the structure, morphology and electrochemical performance of Li4Ti5O12. Results show that the reaction of TiO2 with Li2CO3 is an exothermic behavior. The reactivity of TiO2 with Li2CO3 gradually decreases and the particles size of Li4Ti5O12 increases with the TiO2 crystal structure changing from amorphous to rutile. The TiO2 crystal structure has a slight influence on the reversibility of Li4Ti5O12, while the specific capacities of Li4Ti5O12 at different current densities decreases obviously with the TiO2 crystal structure changing from amorphous to rutile and the sample using amorphous TiO2 as titanium sources shows highest specific capacity. The capacity retentions of all Li4Ti5O12 samples are above 97% after 50 cycles and these materials show good cycle performance. The TiO2 crystal structure has not large effects on the cycling performance of Li4Ti5O12 material.

  12. Anodic oxidation

    CERN Document Server

    Ross, Sidney D; Rudd, Eric J; Blomquist, Alfred T; Wasserman, Harry H

    2013-01-01

    Anodic Oxidation covers the application of the concept, principles, and methods of electrochemistry to organic reactions. This book is composed of two parts encompassing 12 chapters that consider the mechanism of anodic oxidation. Part I surveys the theory and methods of electrochemistry as applied to organic reactions. These parts also present the mathematical equations to describe the kinetics of electrode reactions using both polarographic and steady-state conditions. Part II examines the anodic oxidation of organic substrates by the functional group initially attacked. This part particular

  13. An in situ method of creating metal oxide–carbon composites and their application as anode materials for lithium-ion batteries

    KAUST Repository

    Yang, Zichao

    2011-01-01

    Transition metal oxides are actively investigated as anode materials for lithium-ion batteries (LIBs), and their nanocomposites with carbon frequently show better performance in galvanostatic cycling studies, compared to the pristine metal oxide. An in situ, scalable method for creating a variety of transition metal oxide-carbon nanocomposites has been developed based on free-radical polymerization and cross-linking of poly(acrylonitrile) in the presence of the metal oxide precursor containing vinyl groups. The approach yields a cross-linked polymer network, which uniformly incorporates nanometre-sized transition metal oxide particles. Thermal treatment of the organic-inorganic hybrid material produces nearly monodisperse metal oxide nanoparticles uniformly embedded in a porous carbon matrix. Cyclic voltammetry and galvanostatic cycling electrochemical measurements in a lithium half-cell are used to evaluate the electrochemical properties of a Fe3O 4-carbon composite created using this approach. These measurements reveal that when used as the anode in a lithium battery, the material exhibits stable cycling performance at both low and high current densities. We further show that the polymer/nanoparticle copolymerization approach can be readily adapted to synthesize metal oxide/carbon nanocomposites based on different particle chemistries for applications in both the anode and cathode of LIBs. © 2011 The Royal Society of Chemistry.

  14. Discussion on Anode Material for Lithium Ion Battery%对锂离子电池正极材料的探讨与研究

    Institute of Scientific and Technical Information of China (English)

    罗雨晗

    2015-01-01

    Lithium ion battery is currently widely used ,which has the advantage of long life cycle ,no memory effect , high energy density , large specific capacity , high voltage and smaller volume , etc . Lithium ion battery mainly consists of four parts ,including electrolyte ,membrane ,cathode materials and anode materials .Among them ,the cost of anode material occupies a higher proportion in the total cost ,which is about 40% .Each performance index of the lithium ions are related to the quality of anode materials , so anode material is the core part for lithium ion battery ,which is very crucial .At the same time ,the performance of the battery's anode material can also reduce the manufacturing cost of the lithium battery ,which has a great significance for the industrialization of electric vehicles .%锂离子电池目前应用广泛,有循环寿命长、无记忆效应、能量密度大、比容量大、电池电压高、体积较小等优点。锂离子电池主要由电解液、隔膜、负极材料和正极材料四大部分构成,其中,正极材料的成本在总成本中所占有的比例较高,大约为40%,锂离子的各项性能指标均与正极材料的好坏有密切关系,所以,锂离子正极材料是组成锂离子电池的核心部分,是非常关键的材料,同时,电池正极材料的性能也可以使锂电池的制作成本降低,对于电动汽车的产业化也有较大的意义。

  15. Nano-sized Fe{sub 3}O{sub 4}/carbon as anode material for lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jie [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Zhao, Hailei, E-mail: hlzhao@ustb.edu.cn [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Beijing Key Lab of New Energy Materials and Technologies, Beijing 100083 (China); Zeng, Zhipeng; Lv, Pengpeng; Li, Zhaolin; Zhang, Tianhou; Yang, Tianrang [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China)

    2014-12-15

    Nano-sized Fe{sub 3}O{sub 4}/carbon material is prepared via a simple citric-nitrate combustion method combining with a hydrothermal carbon coating technique. The synthesized Fe{sub 3}O{sub 4}/carbon composite shows a high reversible specific capacity (ca. 850 mAh g{sup −1} at 100 mA g{sup −1}; ca. 600 mAh g{sup −1} at 500 mA g{sup −1}), good rate-capability as well as superior cycling stability as anode for lithium-ion batteries. The ameliorated electrochemical performance of Fe{sub 3}O{sub 4}/carbon electrode is associated to the nano-sized particle feature and the continuous carbon coating layer. The former provides short lithium-ion/electron diffusion distance, while the latter enables the fast electron transport pathways. Besides, the carbon layer can act as a protective component to prevent the active particle Fe{sub 3}O{sub 4} from aggregation and pulverization during the charge/discharge processes. - Highlights: • Nano-sized Fe{sub 3}O{sub 4}/C was prepared by a simple citric-nitrate combustion process. • Fe{sub 3}O{sub 4}/C particles show core–shell structure. • Fe{sub 3}O{sub 4}/C powder displays high specific capacity and good cycling stability. • Fe{sub 3}O{sub 4}/C composite exhibits a superior rate-capability.

  16. Synthesis and electrochemical performance of bud-like FeS2 microspheres as anode materials for rechargeable lithium batteries

    International Nuclear Information System (INIS)

    Highlights: ► Bud-like FeS2 microshperes was synthesized through solvothermal reaction with polyvinylpyrrolidone (PVP). ► Bud-like microshperes in the range of 2.0–3.0 μm are built by nanoflakes with the size of 0.5–1 μm in width and length. ► The bud-like FeS2 is investigated by many tests such as CV, GITT and EIS. ► The bud-like powder shows the highest initial specific capacity, coulombic efficiency and lowest polarization. -- Abstract: Bud-like FeS2 powder was synthesized by a solvothermal method with the help of polyvinylpyrrolidone (PVP). The bud-like FeS2 microshperes with the diameters of 2.0–3.0 μm were consisted of the submicro-flakes with 0.5–1μm in width and length, and about 60 nm in thickness. As an anode material for Li-ion batteries, the bud-like FeS2 delivered initial specific discharge capacity of 773 and 749 mAh g−1, and could sustain 387 and 368 mAh g−1 after 30 cycles at current densities of 45 and 89 mA g−1, respectively, much higher than the solid one obtained without PVP. The bud-like FeS2 microshperes also showed large diffusion coefficient of Li-ions (DLi+) calculated by Galvanostatic intermittent titration (GITT). The improved electrochemical performance of bud-like FeS2 was due to the unique structure which provides large contact area between the FeS2 microspheres and electrolyte, decreased polarization and large DLi+, leading to enhanced electrode reaction kinetics

  17. α-Fe{sub 2}O{sub 3}@C nanorings as anode materials for high performance lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Li, Le; Li, Zhenzhen; Fu, Wenming; Li, Fagen [Department of Physics, Faculty of Science, Ningbo University, Ningbo (China); Wang, Jun, E-mail: wjnaf@ustc.edu [Department of Physics, Faculty of Science, Ningbo University, Ningbo (China); Wang, Wenzhong [School of Science, Minzu University of China, Beijing 100081 (China)

    2015-10-25

    α-Fe{sub 2}O{sub 3}@C core–shell nanorings are prepared by a facile large-scale two-step route incorporating a hydrothermal method and a carbon coated progress. Its structure and morphology are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope, and thermogravimetry. It is found that the as-prepared composite is composed of α-Fe{sub 2}O{sub 3}@C nanorings of about 148 nm in outer diameter, 50 nm in thickness, and 115 nm in length. These α-Fe{sub 2}O{sub 3}@C nanorings are enwrapped with ∼3 nm thick carbon shell. And the electrodes exhibit longer cycle life (815 mAhg{sup −1} after cycling 160 times) at high current rate (1000 mAg{sup −1}) compared with that of bare α-Fe{sub 2}O{sub 3} nanorings (810 mAhg{sup −1} after cycling 30 times). The improved performance of the composite is attributed to the bondage from carbon shell, which can enhance the electronic conductivity and structural stability of α-Fe{sub 2}O{sub 3} nanorings. - Highlights: • α-Fe{sub 2}O{sub 3}@C core–shell nanorings are prepared by a facile two-step route. • The α-Fe{sub 2}O{sub 3}@C nanorings are firstly reported as anode materials for LIBs. • The nanorings show a high capacity of 815 mAhg{sup −1} at 1 Ag{sup -1} after 160 cycles.

  18. Hydrothermally enhanced MnO/reduced graphite oxide composite anode materials for high performance lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: •MnO/RGO with a uniform RGO coating and high specific surface area is synthesized. •The uses of RGO and N2H4 are critical for the electrochemical properties. •The MnO/RGO composite shows a high rate capability and reversible cycling performance. -- Abstract: Nanoplate-assembled MnO2 spheres with a high surface area are synthesized and act as a manganese precursor for the hydrothermal process to synthesize MnO/reduced graphite oxide (MnO/RGO) composite powders. The structures and electrochemical properties of the obtained samples are studied by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, thermal gravimetry, N2 adsorption/desorption measurement and galvanostatic cell cycling. The content of the reduced graphite oxide and the use of the reducing agent (N2H4) are found to play important roles to determine the structures and properties of the MnO/RGO products. The MnO/RGO composites contain a uniform RGO coating and possess a high specific surface area of up to 42.4 m2 g−1. As an anode material for rechargeable lithium batteries, such a MnO/RGO composite can achieve excellent high rate capability and cycling stability. The composite with 13.19 wt% RGO shows the optimal electrochemical performance and can deliver reversible capacities of 855, 842, 821, 737 and 630 mAh g−1 at the current densities of 0.16, 0.4, 0.8, 1.6 and 3.2 A g−1, respectively

  19. Processed data from neutron scattering experiments described in PhD thesis "NMR and neutron total scattering studies of silicon-based anode materials for lithium-ion batteries"

    OpenAIRE

    Kerr, Christopher J

    2015-01-01

    The results of processing the data in the dataset "Raw data for neutron scattering experiments described in PhD thesis "NMR and neutron total scattering studies of silicon-based anode materials for lithium-ion batteries""

  20. Electrodeposition of iron oxide nanorods on carbon nanofiber scaffolds as an anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Iron oxide film with spaced radial nanorods is formed on the VGCF (vapor-grown carbon nanofiber) scaffolds by means of anodic electrodeposition. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy show that the iron oxide film deposited on the VGCF surface is α-Fe2O3 and consists of spaced radial nanorods having 16-21 nm in diameter after annealing at 400 deg. C. Galvanostatic charge/discharge results indicate that the α-Fe2O3/VGCF anode (970 mAh g-1) has higher capacity than bare α-Fe2O3 anode (680 mAh g-1) at 10 C current discharge. VGCF scaffolds fabricated by electrophoretic deposition favor the electron conduction, and the spaced radial nanorods on VGCFs facilitate the migration of lithium ion from the electrolyte. Electrochemical reactions between α-Fe2O3 and lithium ion are therefore improved significantly by this tailored architecture.

  1. Mesoporous Silicon-Based Anodes

    Science.gov (United States)

    Peramunage, Dharmasena

    2015-01-01

    For high-capacity, high-performance lithium-ion batteries. A new high-capacity anode composite based on mesoporous silicon is being developed. With a structure that resembles a pseudo one-dimensional phase, the active anode material will accommodate significant volume changes expected upon alloying and dealloying with lithium (Li).

  2. Carbon-Confined SnO2-Electrodeposited Porous Carbon Nanofiber Composite as High-Capacity Sodium-Ion Battery Anode Material.

    Science.gov (United States)

    Dirican, Mahmut; Lu, Yao; Ge, Yeqian; Yildiz, Ozkan; Zhang, Xiangwu

    2015-08-26

    Sodium resources are inexpensive and abundant, and hence, sodium-ion batteries are promising alternative to lithium-ion batteries. However, lower energy density and poor cycling stability of current sodium-ion batteries prevent their practical implementation for future smart power grid and stationary storage applications. Tin oxides (SnO2) can be potentially used as a high-capacity anode material for future sodium-ion batteries, and they have the advantages of high sodium storage capacity, high abundance, and low toxicity. However, SnO2-based anodes still cannot be used in practical sodium-ion batteries because they experience large volume changes during repetitive charge and discharge cycles. Such large volume changes lead to severe pulverization of the active material and loss of electrical contact between the SnO2 and carbon conductor, which in turn result in rapid capacity loss during cycling. Here, we introduce a new amorphous carbon-coated SnO2-electrodeposited porous carbon nanofiber (PCNF@SnO2@C) composite that not only has high sodium storage capability, but also maintains its structural integrity while ongoing repetitive cycles. Electrochemical results revealed that this SnO2-containing nanofiber composite anode had excellent electrochemical performance including high-capacity (374 mAh g(-1)), good capacity retention (82.7%), and large Coulombic efficiency (98.9% after 100th cycle). PMID:26252051

  3. A first-principles study on the effect of oxygen content on the structural and electronic properties of silicon suboxide as anode material for lithium ion batteries

    Science.gov (United States)

    Rahaman, Obaidur; Mortazavi, Bohayra; Rabczuk, Timon

    2016-03-01

    Silicon suboxide is currently considered as a unique candidate for lithium ion batteries anode materials due to its considerable capacity. However, no adequate information exists about the role of oxygen content on its performance. To this aim, we used density functional theory to create silicon suboxide matrices of various Si:O ratios and investigated the role of oxygen content on the structural, dynamic, electronic properties and lithiation behavior of the matrices. Our study demonstrates that the O atoms interact strongly with the inserted Li atoms resulting in a disintegration of the host matrix. We found that higher concentration of oxygen atoms in the mixture reduces its relative expansion upon lithiation, which is a desirable quality for anode materials. It helps in preventing crack formation and pulverization due to large fluctuations in volume. Our study also demonstrates that a higher oxygen content increases the lithium storage capacity of the anode. However, it can also cause the formation of stable complexes like lithium silicates that might result into reversible capacity loss as indicated by the voltage-composition curves. The study provides valuable insights into the role of oxygen in moderating the interaction of lithium in silicon suboxide mixture in microscopic details.

  4. Facile Sol-Gel/Spray-Drying Synthesis of Interweaved Si@TiO2&CNTs Hybrid Microsphere as Superior Anode Materials for Li-Ion Batteries

    Science.gov (United States)

    Wang, Jiyun; Hou, Xianhua; Li, Yana; Ru, Qiang; Qin, Haiqing; Hu, Shejun

    2016-07-01

    A unique intertwined structure of silicon-based composite (Si@TiO2&CNTs) has been synthesized by sol-gel and spray drying methods. The Si@TiO2&CNTs is mainly composed of three kinds of materials:the prepared nanosilicon particles, TiO2, and carbon nanotubes (CNTs). A layer of TiO2 particles is found effective for enhancing the electrical conductivity and structure stability of the silicon particles. Additionally, the twisted CNTs are beneficial to build a better conductive network, consequently improving the anode working conditions when the cell is charged or discharged. As a lithium ion battery anode, a specific capacity of approximately 1521 mAh g-1 after 100 cycles is obtained.

  5. The Progress of Sodium-Ion Battery Anode Material%钠离子电池负极材料的研究进展

    Institute of Scientific and Technical Information of China (English)

    张洁; 杨占旭

    2016-01-01

    Sodium ion batteries have attracted tremendous attentions due to its rich resources,low cost,high efficiency and good chemical stability,and can satisfy people's demand for energy in the new era,which are considered a top alternative to lithium-ion batteries.The research progress on sodium ion battery anode materials are reviewed in details in this paper, including carbon-based materials,low voltage metal phosphates,the sodium storage alloys,metal oxides,titanium-based materials,and other negative electrode materials.Then the characteristics of anode materials are discussed.Finally,some future directions for sodium-ion battery anode materials are pointed out.%钠离子电池具有资源丰富、成本低、效率高、化学性能稳定等优点,成为锂离子电池 的理想替代品.主要阐述了钠离子电池负极材料的研究进展,包括碳基负极材料、低电压金属磷酸盐负极材料、合金类储钠负极材料、金属氧化物负极材料、钛酸盐类负极材料及其他负极材料,并对各类负极材料的性能进行了评价,最后对钠离子电池负极材料的发展方向做出了展望.

  6. Multi-walled carbon nanotube-reinforced porous iron oxide as a superior anode material for lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Pang, Xin-Jing; Zhang, Juan; Qi, Gong-Wei; Dai, Xiao-Hui; Zhou, Jun-Ping [School of Chemistry and Chemical Engineering, Shandong University, No. 27, Shanda Nan Rd., Jinan 250100 (China); Zhang, Shu-Yong, E-mail: syzhang@sdu.edu.cn [School of Chemistry and Chemical Engineering, Shandong University, No. 27, Shanda Nan Rd., Jinan 250100 (China); National Key Lab of Crystal, Shandong University, No. 27, Shanda Nan Rd., Jinan 250100 (China)

    2015-08-15

    Highlights: • Electrochemical performance of Fe{sub 3}O{sub 4} is improved by combining different approaches. • Porous Cu substrate is used to enlarge surface area and improve conductivity. • MWCNT is used to reinforce the electrode structure and change morphology of Fe{sub 3}O{sub 4}. • Reversible capacity, capacity retention and high-rate performance are improved. - Abstract: Multi-walled carbon nanotube-reinforced porous iron oxide (Fe{sub 3}O{sub 4}/MWCNT) is synthesized by a two-step approach with porous Cu substrate serving as current collector. Porous Cu substrate is prepared through electroless deposition with hydrogen bubble serving as template. Fe{sub 3}O{sub 4}/MWCNT composites are prepared by the electrodeposition of Fe{sub 3}O{sub 4} in the presence of dispersed MWCNTs from a Fe{sub 2}(SO{sub 4}){sub 3} solution with MWCNT suspension. Results showed that Fe{sub 3}O{sub 4} forms granular nanoparticles on the porous Cu substrate with several MWCNTs embedded in it. Adding MWCNTs changes the morphology of Fe{sub 3}O{sub 4}. Smooth Fe{sub 3}O{sub 4}, smooth Fe{sub 3}O{sub 4}/MWCNT, and porous Fe{sub 3}O{sub 4} composites are also prepared for comparison. When used as anode materials, porous Fe{sub 3}O{sub 4}/MWCNT composites have a reversible capacity of approximately 601 mA h g{sup −1} at the 60th cycle at a cycling rate of 100 mA g{sup −1}. This value is higher than that of the other materials. The reversible capacity at a cycling rate of 10,000 mA g{sup −1} is approximately 50% of that at 100 mA g{sup −1}. Therefore, the MWCNT-reinforced porous Fe{sub 3}O{sub 4} composite exhibits much better reversible capacity, capacity retention, and high-rate performance than the other samples. This finding can be ascribed to the porous structure of Fe{sub 3}O{sub 4}, better conductivity of porous Cu substrate and MWCNTs, and the morphology change of Fe{sub 3}O{sub 4} nanoparticles upon the addition of MWCNTs.

  7. Ultrafast synthesis of MoS2 or WS2-reduced graphene oxide composites via hybrid microwave annealing for anode materials of lithium ion batteries

    Science.gov (United States)

    Youn, Duck Hyun; Jo, Changshin; Kim, Jae Young; Lee, Jinwoo; Lee, Jae Sung

    2015-11-01

    An ultrafast and simple strategy to synthesize metal sulfides (MoS2 and WS2) anchored on reduced graphene oxide (RGO) composites is reported as anode materials for lithium ion batteries (LIBs). Metal sulfide nanocrystals with homogeneous dispersion onto conducting RGO sheets are obtained in only 45 s by hybrid microwave annealing (HMA) method. The synthesized materials, especially MoS2/RGO composite, exhibit a high Li capacity, an excellent rate capability, and a stable cycling performance, comparable to the reported best MS2/carbon composite electrodes. The results highlight the effectiveness of HMA method to fabricate the metal sulfide/RGO composites with excellent electric properties.

  8. SnO2 nanocrystals deposited on multiwalled carbon nanotubes with superior stability as anode material for Li-ion batteries

    Science.gov (United States)

    Ren, Jianguo; Yang, Junbing; Abouimrane, Ali; Wang, Dapeng; Amine, Khalil

    2011-10-01

    We report a novel ethylene glycol-mediated solvothermal-polyol route for synthesis of SnO2-CNT nanocomposites, which consist of highly dispersed 3-5 nm SnO2 nanocrystals on the surface of multiwalled carbon nanotubes (CNTs). As anode materials for Li-ion batteries, the nanocomposites showed high rate capability and superior cycling stability with specific capacity of 500 mAh g-1 for up to 300 cycles. The CNTs served as electron conductors and volume buffers in the nanocomposites. This strategy could be extended to synthesize other metal oxides composites with other carbon materials.

  9. Preparation and electrochemical properties of core-shell carbon coated Mn–Sn complex metal oxide as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    In this study, we synthesized a carbon coated Mn–Sn metal oxide composite with core-shell structure (MTO@C) via a simple glucose hydrothermal reaction and subsequent carbonization approach. When the MTO@C composite was applied as an anode material for lithium-ion batteries, it maintained a reversible capacity of 409 mA h g−1 after 200 cycles at a current density of 100 mA g−1. The uniformed and continuous carbon layer formed on the MTO nanoparticles, effectively buffered the volumetric change of the active material and increased electronic conductivity, which thus prolonged the cycling performance of the MTO@C electrode.

  10. Nano-sized Li4Ti5O12 anode material with excellent performance prepared by solid state reaction: The effect of precursor size and morphology

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Nano-sized Li4Ti5O12 has been prepared through solid state reaction by using axiolitic TiO2 as precursor. • The prepared nano-sized Li4Ti5O12 anode material shows excellent electrochemical performance. • The utilization of precursor with special morphology and size is one of the useful ways to prepare more active electrode materials. - Abstract: Spinel nano-sized Li4Ti5O12 anode material of secondary lithium-ion battery has been successfully prepared by solid state reaction using axiolitic TiO2 assembled by 10–20 nm nanoparticles and Li2CO3 as precursors. The synthesis condition, grain size effect and corresponding electrochemical performance of the special Li4Ti5O12 have been studied in comparison with those of the normal Li4Ti5O12 originated from commercial TiO2. We also propose the mechanism that using the nano-scaled TiO2 with special structure and unexcess Li2CO3 as precursors can synthesize pure phase nano-sized Li4Ti5O12 at 800 °C through solid state reaction. The prepared nano-sized Li4Ti5O12 anode material for Li-ion batteries shows excellent capacity performance with rate capacity of 174.2, 164.0, 157.4, 146.4 and 129.6 mA h g−1 at 0.5, 1, 2, 5 and 10 C, respectively, and capacity retention of 95.1% after 100 cycles at 1 C. In addition, the specific capacity fade for the cell with the different Li4Ti5O12 active materials resulted from the increase of internal resistance after 100 cycles is compared

  11. TiNb2O7/Graphene hybrid material as high performance anode for lithium-ion batteries

    International Nuclear Information System (INIS)

    We report the synthesis of TiNb2O7/Graphene (TNO-TG) hybrid nanomaterial by simple solvothermal process, with TiNb2O7 nanoparticles anchored on the reduced graphene oxide (rGO) sheets. TNO-TG hybrid nanomaterial showed excellent electrochemical performance when studied as anode for Lithium-ion battery, with an exceptionally high rate capability (capacity retention of 80% at 16 C rate) along with high discharge capacity (∼230 mAhg−1 after 50 cycles at 0.1 C). A full cell Li-ion battery has been fabricated with TNO-TG as anode and LiNi1/3Mn1/3Co1/3O2:LiNi0.5Mn0.5O2 (wt% of 75:25) as cathode, which delivered an average cell voltage of ∼2.5 V with an initial anode-specific discharge capacity of 211 mAhg−1, when cycled in the voltage range of 1.5–3.5 V at 0.1 C. The obtained results are very promising and we believe the current findings will lead to new directions in the on-going search for safe and high performance anodes for rechargeable lithium-ion batteries

  12. Multiwalled carbon nanotube@a-C@Co9S8 nanocomposites: a high-capacity and long-life anode material for advanced lithium ion batteries

    Science.gov (United States)

    Zhou, Yanli; Yan, Dong; Xu, Huayun; Liu, Shuo; Yang, Jian; Qian, Yitai

    2015-02-01

    A one-dimensional MWCNT@a-C@Co9S8 nanocomposite has been prepared via a facile solvothermal reaction followed by a calcination process. The amorphous carbon layer between Co9S8 and MWCNT acts as a linker to increase the loading of sulfides on MWCNT. When evaluated as anode materials for lithium ion batteries, the MWCNT@a-C@Co9S8 nanocomposite shows the advantages of high capacity and long life, superior to Co9S8 nanoparticles and MWCNT@Co9S8 nanocomposites. The reversible capacity could be retained at 662 mA h g-1 after 120 cycles at 1 A g-1. The efficient synthesis and excellent performances of this nanocomposite offer numerous opportunities for other sulfides as a new anode for lithium ion batteries.A one-dimensional MWCNT@a-C@Co9S8 nanocomposite has been prepared via a facile solvothermal reaction followed by a calcination process. The amorphous carbon layer between Co9S8 and MWCNT acts as a linker to increase the loading of sulfides on MWCNT. When evaluated as anode materials for lithium ion batteries, the MWCNT@a-C@Co9S8 nanocomposite shows the advantages of high capacity and long life, superior to Co9S8 nanoparticles and MWCNT@Co9S8 nanocomposites. The reversible capacity could be retained at 662 mA h g-1 after 120 cycles at 1 A g-1. The efficient synthesis and excellent performances of this nanocomposite offer numerous opportunities for other sulfides as a new anode for lithium ion batteries. Electronic supplementary information (ESI) available: Infrared spectrogram (IR) of glucose treated MWCNT; TEM images of MWCNT@a-C treated by different concentrations of glucose; SEM and TEM images of the intermediate product obtained from the solvothermal reaction between thiourea and Co(Ac)2; EDS spectrum of MWCNT@a-C@Co9S8 composites; SEM and TEM images of MWCNT@Co9S8 nanocomposites obtained without the hydrothermal treatment by glucose; SEM and TEM images of Co9S8 nanoparticles; Galvanostatic discharge-charge profiles and cycling performance of MWCNT@a-C; TEM images

  13. Synthesis of nickel oxide nanospheres by a facile spray drying method and their application as anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: NiO nanospheres prepared by a facile spray drying method show high lithium ion storage performance as anode of lithium ion battery. - Highlights: • NiO nanospheres are prepared by a spray drying method. • NiO nanospheres are composed of interconnected nanoparticles. • NiO nanospheres show good lithium ion storage properties. - Abstract: Fabrication of advanced anode materials is indispensable for construction of high-performance lithium ion batteries. In this work, nickel oxide (NiO) nanospheres are fabricated by a facial one-step spray drying method. The as-prepared NiO nanospheres show diameters ranging from 100 to 600 nm and are composed of nanoparticles of 30–50 nm. As an anode for lithium ion batteries, the electrochemical properties of the NiO nanospheres are investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge tests. The specific reversible capacity of NiO nanospheres is 656 mA h g−1 at 0.1 C, and 476 mA h g−1 at 1 C. The improvement of electrochemical properties is attributed to nanosphere structure with large surface area and short ion/electron transfer path

  14. FeS anchored reduced graphene oxide nanosheets as advanced anode material with superior high-rate performance for alkaline secondary batteries

    Science.gov (United States)

    Shangguan, Enbo; Guo, Litan; Li, Fei; Wang, Qin; Li, Jing; Li, Quanmin; Chang, Zhaorong; Yuan, Xiao-Zi

    2016-09-01

    A new nanocomposite formulation of the iron-based anode for alkaline secondary batteries is proposed. For the first time, FeS nanoparticles anchored on reduced graphene oxide (RGO) nanosheets are synthesized via a facile, environmentally friendly direct-precipitation approach. In this nanocomposite, FeS nanoparticles are anchored uniformly and tightly on the surface of RGO nanosheets. As an alkaline battery anode, the FeS@RGO electrode delivers a superior high-rate charge/discharge capability and outstanding cycling stability, even at a condition without any conductive additives and a high electrode loading of ∼40 mg cm-2. At high charge/discharge rates of 5C, 10C and 20C (6000 mA g-1), the FeS@RGO electrode presents a specific capacity of ∼288, 258 and 220 mAh g-1, respectively. Moreover, the FeS@RGO electrode exhibits an admirable long cycling stability with a superior capacity retention of 87.6% for 300 cycles at a charge/discharge rate of 2C. The excellent electrochemical properties of the FeS@RGO electrode can be stemmed from the high specific surface area, peculiar electric conductivity and robust sheet-anchored structure of the FeS@RGO nanocomposite. By virtue of its superior fast charge/discharge properties, the FeS@RGO nanocomposite is suitable as an advanced anode material for high-performance alkaline secondary batteries.

  15. Synthesis of nickel oxide nanospheres by a facile spray drying method and their application as anode materials for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Anguo, E-mail: hixiaoanguo@126.com; Zhou, Shibiao; Zuo, Chenggang; Zhuan, Yongbing; Ding, Xiang

    2015-10-15

    Graphical abstract: NiO nanospheres prepared by a facile spray drying method show high lithium ion storage performance as anode of lithium ion battery. - Highlights: • NiO nanospheres are prepared by a spray drying method. • NiO nanospheres are composed of interconnected nanoparticles. • NiO nanospheres show good lithium ion storage properties. - Abstract: Fabrication of advanced anode materials is indispensable for construction of high-performance lithium ion batteries. In this work, nickel oxide (NiO) nanospheres are fabricated by a facial one-step spray drying method. The as-prepared NiO nanospheres show diameters ranging from 100 to 600 nm and are composed of nanoparticles of 30–50 nm. As an anode for lithium ion batteries, the electrochemical properties of the NiO nanospheres are investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge tests. The specific reversible capacity of NiO nanospheres is 656 mA h g{sup −1} at 0.1 C, and 476 mA h g{sup −1} at 1 C. The improvement of electrochemical properties is attributed to nanosphere structure with large surface area and short ion/electron transfer path.

  16. 锂离子电池硅基负极材料研究进展%Research Progress of Silicon Based Anode Materials for Lithium-ion Batteries

    Institute of Scientific and Technical Information of China (English)

    杨绍斌; 刘远鹏

    2011-01-01

    Silicon based materials are candidate anode materials for lithium-ion battery because of its large spe cific capacity. But the decay of capacity during cycling restrains the practicability of silicon-based material. Two im portant research aspects of silicon-based materials are reviewed, including the silicon compounds powder and silicon thin film, and a single modification approach cannot satisfy the practical application is pointed out So, the comprehen sive use of nanocrystallization, amorphization and alloying becomes the main approach in silicon, based anode mate rials.%硅基负极材料具有比容量大的优点,是高容量锂离子电池理想的负极材料.然而硅基材料在循环过程中容量衰减快,影响了其实用性.从硅复合物粉末和硅薄膜两个重要研究方面对硅基负极材料进行了综述,指出在Si基复合负极材料的研究中,单一途径改性提升循环性能的幅度有限,很难达到实用化阶段.硅的纳米化、无定形化、合金化及复合化等方法的综合运用成为硅基材料研究的主导方向.

  17. Enhanced cycle stability of micro-sized Si/C anode material with low carbon content fabricated via spray drying and in situ carbonization

    International Nuclear Information System (INIS)

    Highlights: • Micro-sized Si/C composites were fabricated via. spray drying and carbonization. • Multi-morphology carbon was formed in the Si/C composites. • Si/C composite with 5.6 wt.% C provides significant improved cycling stability. • Multi-morphology carbon plays effective role in improving the electrochemical property. • The method provides potential for mass production of superior Si-based anode materials. - Abstract: Micro-sized Si/C composites with in situ introduced carbon of multi-morphology were fabricated via spray drying a suspension of commercial micro-sized Si and citric acid followed by a carbonization. Different ratios of Si to citric acid were used to optimize the composition and structure of the composites and thus the electrochemical performance. Carbon flakes including crooked and flat ones were well dispersed in between the Si particles, forming Si/C composites. Floc-like carbon layers and carbon fragments were also found to cover partially the Si particles. The Si/C composite with a low carbon content of 5.6 wt.% provides an initial reversible capacity of 2700 mA h/g and a capacity of 1860 mA h/g after 60 cycles at a current density of 100 mA/g as anode material for lithium-ion batteries (LIBs), which are much higher than those of pristine Si and the Si/C composites with higher carbon content. The mechanism of the enhancement of electrochemical performance of the micro-sized Si/C composite is discussed. The fabrication method and the structure design of the composites offer valuable potential in developing adaptable Si-based anode materials for industrial applications

  18. Anode sheath transition in an anodic arc for synthesis of nanomaterials

    Science.gov (United States)

    Nemchinsky, V. A.; Raitses, Y.

    2016-06-01

    The arc discharge with ablating anode or so-called anodic arc is widely used for synthesis of nanomaterials, including carbon nanotubes and fullerens, metal nanoparticles etc. We present the model of this arc, which confirms the existence of the two different modes of the arc operation with two different anode sheath regimes, namely, with negative anode sheath and with positive anode sheath. It was previously suggested that these regimes are associated with two different anode ablating modes—low ablation mode with constant ablation rate and the enhanced ablation mode (Fetterman et al 2008 Carbon 46 1322). The transition of the arc operation from low ablation mode to high ablation mode is determined by the current density at the anode. The model can be used to self-consistently determine the distribution of the electric field, electron density and electron temperature in the near-anode region of the arc discharge. Simulations of the carbon arc predict that for low arc ablating modes, the current is driven mainly by the electron diffusion to the anode. For positive anode sheath, the anode voltage is close to the ionization potential of anode material, while for negative anode sheath, the anode voltage is an order of magnitude smaller. It is also shown that the near-anode plasma, is far from the ionization equilibrium.

  19. N-doped graphene/graphite composite as a conductive agent-free anode material for lithium ion batteries with greatly enhanced electrochemical performance

    International Nuclear Information System (INIS)

    Graphical abstract: The study reported a novel N-doped graphene/graphite anode material for lithium ion batteries. The composite exhibits a largely enhanced electrochemical performance. The study also provides an attractive approach for the fabrication of various graphite-based materials for high power batteries. Display Omitted -- Highlights: • The paper developed a new N-doped graphene/graphite composite for lithium ion battery • The composite contains a three-dimensional graphene framework with rich of open pores • The hybrid offers a higher electrical conductivity when compared with pristine graphite • The hybrid electrode provides a greatly enhanced electrochemical performance • The study provides a prominent approach for fabrication of graphite-based materials -- ABSTRACT: Present graphite anode cannot meet the increasing requirement of electronic devices and electric vehicles due to its low specific capacity, poor cycle stability and low rate capability. The study reported a promising N-doped graphene/graphite composite as a conductive agent-free anode material for lithium ion batteries. Herein, graphite oxide and urea were dispersed in ultrapure water and partly reduced by ascorbic acid. Followed by mixing with graphite and hydrothermal treatment to produce graphene oxide/graphite hydrogel. The hydrogel was dried and finally annealed in Ar/H2 to obtain N-doped graphene/graphite composite. The result shows that all of graphite particles was dispersed in three-dimensional graphene framework with a rich of open pores. The open pore accelerates the electrolyte transport. The graphene framework works as a conductive agent and graphite particle connector and improves the electron transfer. Electrical conductivity of the composite reaches 5912 S m−1, which is much better than that of the pristine graphite (4018 S m−1). The graphene framework also acts as an expansion absorber in the anodes of lithium ion battery to relieve the large strains developed

  20. Synthesis and characterization of Li2Zn0.6Cu0.4Ti3O8 anode material via a sol-gel method

    International Nuclear Information System (INIS)

    Highlights: •Li2Zn0.6Cu0.4Ti3O8 has been synthesized via sol-gel method for the first time. •The electrochemical performances of Li2Zn0.6Cu0.4Ti3O8 are investigated. •The Li2Zn0.6Cu0.4Ti3O8 anode shows excellent cycle stability and rate capability. •The charge capacities retains 154.8 mAh g−1 after 50 cycles at 1 A g−1. -- Abstract: Li2Zn0.6Cu0.4Ti3O8 anode material was synthesized by a sol-gel method and the precursor calcinations. The sample is characterized by X-ray diffraction patterns (XRD), scanning electron microscope (SEM), Transmission Electron microscopy(TEM), galvanostatic charge-discharge tests, cyclic voltammetry (CV) tests, and electrochemical impedance spectroscopy (EIS). The results shows the nanoparticles were high crystalline and their size was found to be ca. 50–100 nm. The electrochemical measurements indicate that the anode material made of Li2Zn0.6Cu0.4Ti3O8 displayed a highly reversible capacity and excellent cycling stability. The initial charge capacities of Li2Zn0.6Cu0.4Ti3O8 are 239.5 mAh g−1, 225.8 mAh g−1, 217.4 mAh g−1,190.5 mAh g−1 and 171.6 mA h g−1 at 50 mA g−1, 100 mA g−1, 300 mA g−1, 500 mA g−1 and 1000 mA g−1,respectively. After 50 cycles, the charge capacity of 196.3 mAh g−1, 190.1 mAh g−1, 177.3 mAh g−1, 161.5 mAh g−1 and 154.8 mAh g−1 could be retained. This indicates that the Li2Zn0.6Cu0.4Ti3O8 material is a promising anode material for lithium-ion batteries

  1. Co3O4 nanoparticles embedded in ordered mesoporous carbon with enhanced performance as an anode material for Li-ion batteries

    International Nuclear Information System (INIS)

    A Co3O4/ordered mesoporous carbon (OMC) nanocomposite, in which Co3O4 nanoparticles (NPs), with an average size of about 10 nm homogeneously embedded in the OMC framework, are prepared for use as an anode material in Li-ion batteries. The composite is prepared by a one-pot synthesis based on the solvent evaporation-induced co-self-assembly of a phenolic resol, a triblock copolymer F127, and Co(NO3)2·6H2O, followed by carbonization and oxidation. The resulting material has a high reversible capacity of ∼1,025 mA h g−1 after 100 cycles at a current density of 0.1 A g−1. The enhanced cycling stability and rate capability of the composite can be attributed to the combined mesoporous nanostructure which provides efficient pathways for Li-ion transport and the homogeneous distribution of the Co3O4 NPs in the pore wall of the OMC, which prevents aggregation. These findings suggest that the OMC has promise for use as a carbon metric for metals and metal oxides as an anode material in high performance Li-ion batteries

  2. Enhanced rate performance of nanosized Li4Ti5O12/graphene composites as anode material by a solid state-assembly method

    International Nuclear Information System (INIS)

    Highlights: • Nanosized Li4Ti5O12/graphene material synthesized by a solid state-assembly method is first reported. • Li4Ti5O12/graphene materials exhibit high specific capacity and cycle stability. • Li4Ti5O12/graphene anodes remarkably exhibit high rate performance. • Li4Ti5O12/graphene improves the conductivity. -- Abstract: Nanosized Li4Ti5O12/graphene materials have been successfully synthesized by a solid state-assembly method. As the anode materials for lithium ion batteries, nanosized Li4Ti5O12/graphene exhibits higher specific capacity, much improved rate capability, and better cycle stability than the pure Li4Ti5O12. In the potential range of 1.0-2.0 V at room temperature, Li4Ti5O12/graphene with weight ratio of LTO:GO to 1000:5 shows discharge capacities of more than 144 and 96.2 mAh g−1 after 100 cycles at 1C and 3C charge-discharge rates, while the correspond discharge capacities of pure Li4Ti5O12 are only 108 and 75.4 mAh g−1, respectively. The resulting Li4Ti5O15/graphene (1000:5) sample demonstrates remarkable rate capability in that it delivers a reversible capacity of 53.4 mAh g−1 in the 1000th cycle at 10C charge-discharge rate, about 240% that of pristine Li4Ti5O12 particles (22.2 mAh g−1). The low charge-transfer resistance and large lithium ion diffusion coefficients confirmed that Li4Ti5O12/graphene materials possessed better electronic conductivity and lithium ion mobility. The present work demonstrates that Li4Ti5O12/graphene composite is a promising anode material for high-rate and long life lithium ion batteries and this simple preparation method makes its production on a large scale

  3. A novel nano-structured interpenetrating phase composite of silicon/graphite–tin for lithium-ion rechargeable batteries anode materials

    International Nuclear Information System (INIS)

    Highlights: • An interpenetrating phase composite is synthesized by high energy mechanical milling. • Silicon and tin interpenetrate into each other in the composite. • The SGM composite shows good electrochemical properties. • The lithiation and delithiation reaction mechanism are investigated. - Abstract: A novel nano-structured interpenetrating phase composite (NSIPC) of silicon/graphite–tin (SGM) anode material for lithium-ion rechargeable batteries is synthesized by high energy mechanical milling (HEMM). The structural and morphological characterizations have been carried out through X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical performances have been analyzed with reference to Li+/Li and the results are compared with silicon/graphite composites. The SGM NSIPC electrode exhibits the better cyclability than the SG composite electrodes. The initial discharge specific capacity of the as-prepared SGM NSIPC is relatively high around 1790 mA h g−1 with 1592 mA h g−1 reversible capacity retention in the following cycle at a current density of 237 mA g−1 in the voltage from 0.03 V to 1.5 V. In addition, the SGM NSIPC electrode shows the good rate capability and possesses the stable cycling performance even charging and discharging at the large current density. Consequently, SGM NSIPC can be the promising anode material for the next generation lithium ion rechargeable batteries

  4. A three-dimensional porous MoP@C hybrid as a high-capacity, long-cycle life anode material for lithium-ion batteries.

    Science.gov (United States)

    Wang, Xia; Sun, Pingping; Qin, Jinwen; Wang, Jianqiang; Xiao, Ying; Cao, Minhua

    2016-05-21

    Metal phosphides are great promising anode materials for lithium-ion batteries with a high gravimetric capacity. However, significant challenges such as low capacity, fast capacity fading and poor cycle stability must be addressed for their practical applications. Herein, we demonstrate a versatile strategy for the synthesis of a novel three-dimensional porous molybdenum phosphide@carbon hybrid (3D porous MoP@C hybrid) by a template sol-gel method followed by an annealing treatment. The resultant hybrid exhibits a 3D interconnected ordered porous structure with a relatively high surface area. Benefiting from its advantages of microstructure and composition, the 3D porous MoP@C hybrid displays excellent lithium storage performance as an anode material for lithium-ion batteries in terms of specific capacity, cycling stability and long-cycle life. It presents stable cycling performance with a high reversible capacity up to 1028 mA h g(-1) at a current density of 100 mA g(-1) after 100 cycles. By ex situ XRD, HRTEM, SAED and XPS analyses, the 3D porous MoP@C hybrid was found to follow the Li-intercalation reaction mechanism (MoP + xLi(+) + e(-)↔ LixMoP), which was further confirmed by ab initio calculations based on density functional theory. PMID:27136974

  5. Hierarchical Carbon with High Nitrogen Doping Level: A Versatile Anode and Cathode Host Material for Long-Life Lithium-Ion and Lithium-Sulfur Batteries.

    Science.gov (United States)

    Reitz, Christian; Breitung, Ben; Schneider, Artur; Wang, Di; von der Lehr, Martin; Leichtweiss, Thomas; Janek, Jürgen; Hahn, Horst; Brezesinski, Torsten

    2016-04-27

    Nitrogen-rich carbon with both a turbostratic microstructure and meso/macroporosity was prepared by hard templating through pyrolysis of a tricyanomethanide-based ionic liquid in the voids of a silica monolith template. This multifunctional carbon not only is a promising anode candidate for long-life lithium-ion batteries but also shows favorable properties as anode and cathode host material owing to a high nitrogen content (>8% after carbonization at 900 °C). To demonstrate the latter, the hierarchical carbon was melt-infiltrated with sulfur as well as coated by atomic layer deposition (ALD) of anatase TiO2, both of which led to high-quality nanocomposites. TiO2 ALD increased the specific capacity of the carbon while maintaining high Coulombic efficiency and cycle life: the composite exhibited stable performance in lithium half-cells, with excellent recovery of low rate capacities after thousands of cycles at 5C. Lithium-sulfur batteries using the sulfur/carbon composite also showed good cyclability, with reversible capacities of ∼700 mA·h·g(-1) at C/5 and without obvious decay over several hundred cycles. The present results demonstrate that nitrogen-rich carbon with an interconnected multimodal pore structure is very versatile and can be used as both active and inactive electrode material in high-performance lithium-based batteries. PMID:26867115

  6. Interfacial effect on the electrochemical properties of the layered graphene/metal sulfide composites as anode materials for Li-ion batteries

    Science.gov (United States)

    Lv, Yagang; Chen, Biao; Zhao, Naiqin; Shi, Chunsheng; He, Chunnian; Li, Jiajun; Liu, Enzuo

    2016-09-01

    The layered graphene/metal sulfide composites exhibit excellent electrochemical properties as anode materials for lithium ion battery, due to the synergistic effect between metal sulfide and graphene which still needs to be further understood. In this study, Li adsorption and diffusion on MoS2 and SnS2 monolayers and Li2S surface, as well as at their interfaces with graphene, are systematically investigated through first-principles calculations. The analysis of charge density difference, Bader charge, and density of states indicates that the adsorbed Li atoms interact with both the S atoms at metal sulfide surfaces and C atoms in graphene, resulting in larger Li adsorption energies at the interfaces compared with that on the corresponding surfaces, but with almost no enhancement of the energy barriers for Li atom diffusion. The enhanced Li adsorption capability at Li2S/G interface contributes to the extra storage capacity of graphene/metal sulfide composites. Furthermore, the synergistic mechanism between metal sulfide and graphene is revealed. Moreover, band structure analysis shows the electronic conductivity is enhanced with the incorporation of graphene. The results corroborate the interfacial pseudocapacity-like Li atom storage mechanism, and are helpful for the design of layered graphene/metal sulfide composites as anode materials for lithium ion batteries.

  7. Integrating 3D Flower-Like Hierarchical Cu2NiSnS4 with Reduced Graphene Oxide as Advanced Anode Materials for Na-Ion Batteries.

    Science.gov (United States)

    Yuan, Shuang; Wang, Sai; Li, Lin; Zhu, Yun-hai; Zhang, Xin-bo; Yan, Jun-min

    2016-04-13

    Development of an anode material with high performance and low cost is crucial for implementation of next-generation Na-ion batteries (NIBs) electrode, which is proposed to meet the challenges of large scale renewable energy storage. Metal chalcogenides are considered as promising anode materials for NIBs due to their high theoretical capacity, low cost, and abundant sources. Unfortunately, their practical application in NIBs is still hindered because of low conductivity and morphological collapse caused by their volume expansion and shrinkage during Na(+) intercalation/deintercalation. To solve the daunting challenges, herein, we fabricated novel three-dimensional (3D) Cu2NiSnS4 nanoflowers (CNTSNs) as a proof-of-concept experiment using a facile and low-cost method. Furthermore, homogeneous integration with reduced graphene oxide nanosheets (RGNs) endows intrinsically insulated CNTSNs with superior electrochemical performances, including high specific capacity (up to 837 mAh g(-1)), good rate capability, and long cycling stability, which could be attributed to the unique 3D hierarchical structure providing fast ion diffusion pathway and high contact area at the electrode/electrolyte interface. PMID:26986821

  8. Hierarchical MoS2 tubular structures internally wired by carbon nanotubes as a highly stable anode material for lithium-ion batteries

    Science.gov (United States)

    Chen, Yu Ming; Yu, Xin Yao; Li, Zhen; Paik, Ungyu; Lou, Xiong Wen (David)

    2016-01-01

    Molybdenum disulfide (MoS2), a typical two-dimensional material, is a promising anode material for lithium-ion batteries because it has three times the theoretical capacity of graphite. The main challenges associated with MoS2 anodes are the structural degradation and the low rate capability caused by the low intrinsic electric conductivity and large strain upon cycling. Here, we design hierarchical MoS2 tubular structures internally wired by carbon nanotubes (CNTs) to tackle these problems. These porous MoS2 tubular structures are constructed from building blocks of ultrathin nanosheets, which are believed to benefit the electrochemical reactions. Benefiting from the unique structural and compositional characteristics, these CNT-wired MoS2 tubular structures deliver a very high specific capacity of ~1320 mAh g−1 at a current density of 0.1 A g−1, exceptional rate capability, and an ultralong cycle life of up to 1000 cycles. This work may inspire new ideas for constructing high-performance electrodes for electrochemical energy storage. PMID:27453938

  9. A novel Co-Li2O@Si core-shell nanowire array composite as a high-performance lithium-ion battery anode material

    Science.gov (United States)

    Zhao, Wenjia; Du, Ning; Zhang, Hui; Yang, Deren

    2016-02-01

    We report a novel material of Co-Li2O@Si core-shell nanowire array synthesized via the lithiation of pre-synthesized CoO@Si core-shell nanowire arrays during the first cycle. When the potential window versus lithium was controlled between 0.01-1.2 V, the coated Si shell could be electrochemically active, while the Co-Li2O nanowire core could function as a stable mechanical support and an efficient electron conducting pathway during the charge-discharge process. The Co-Li2O@Si core-shell nanowire array anodes exhibit good cyclic stability and high power capability compared to planar Si film electrodes.We report a novel material of Co-Li2O@Si core-shell nanowire array synthesized via the lithiation of pre-synthesized CoO@Si core-shell nanowire arrays during the first cycle. When the potential window versus lithium was controlled between 0.01-1.2 V, the coated Si shell could be electrochemically active, while the Co-Li2O nanowire core could function as a stable mechanical support and an efficient electron conducting pathway during the charge-discharge process. The Co-Li2O@Si core-shell nanowire array anodes exhibit good cyclic stability and high power capability compared to planar Si film electrodes. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06120b

  10. Synthesis and Application of Si/Carbon Nanofiber Composites Based on Ni and Mo Catalysts for Anode Material of Lithium Secondary Batteries.

    Science.gov (United States)

    Jang, Eunyi; Park, Heal-Ku; Lee, Chang-Seop

    2016-05-01

    In this paper, carbon nanofibers (CNFs) and Si/carbon nanofiber composites were synthesized for use as the anode material of lithium secondary batteries. Catalysts were prepared based on Ni and Mo metals and CNFs were grown through chemical vapor deposition (CVD). In addition, the grown CNFs were mixed with silicon particles to synthesize Si/carbon nanofibers composites. The physiochemical characteristics of the synthesized CNFs and Si/carbon nanofiber composites were analyzed by SEM, EDS, XRD, Raman, BET and XPS. The electrochemical characteristics were investigated by using cyclic voltammetry and galvanostatic charge-discharge. Using CNFs and Si/carbon nanofiber composites as the anode material, three electrode cells were assembled and the electrochemical characteristics were measured using LiPF6 and LiClO4 as electrolytes. As a result of the galvanostatic charge-discharge of CNFs that were grown through catalysts with Ni and Mo concentration ratio of 6:4, the initial discharge capacity when using LiPF6 as the electrolyte was 570 mAh/g and the retention rate was 15.05%. In the case of using LiClO4 as the electrolyte, the initial discharge capacity was 263 mAh/g and the retention rate was 67.23%. PMID:27483824

  11. Hybrid CuO/SnO{sub 2} nanocomposites: Towards cost-effective and high performance binder free lithium ion batteries anode materials

    Energy Technology Data Exchange (ETDEWEB)

    Xing, G. Z. [Pillar of Engineering Product Development, Singapore University of Technology and Design, 20 Dover Drive, Singapore 138682 (Singapore); School of Materials Science and Engineering, The University of New South Wales, Sydney, New South Wales 2052 (Australia); Wang, Y.; Wong, J. I.; Shi, Y. M.; Huang, Z. X.; Yang, H. Y., E-mail: yanghuiying@sutd.edu.sg [Pillar of Engineering Product Development, Singapore University of Technology and Design, 20 Dover Drive, Singapore 138682 (Singapore); Li, S. [School of Materials Science and Engineering, The University of New South Wales, Sydney, New South Wales 2052 (Australia)

    2014-10-06

    Hybrid CuO/SnO{sub 2} nanocomposites are synthesized by a facile thermal annealing method on Cu foils. Compared to pristine CuO and SnO{sub 2} nanostructures, hybrid CuO/SnO{sub 2} nanocomposites exhibit the enhanced electrochemical performances as the anode material of lithium ion batteries (LIBs) with high specific capacity and excellent rate capability. The binder free CuO/SnO{sub 2} nanocomposites deliver a specific capacity of 718 mA h g{sup −1} at a current density of 500 mA g{sup −1} even after 200 cycles. The enhanced electrochemical performances are attributed to the synergistic effect between SnO{sub 2} nanoparticles and CuO nanoarchitectures. Such hybrid CuO/SnO{sub 2} nanocomposites could open up a new route for the development of next-generation high-performance and cost-effective binder free anode material of LIBs for mass production.

  12. Flake-by-flake ZnCo2O4 as a high capacity anode material for lithium-ion battery

    International Nuclear Information System (INIS)

    Highlights: • The ZnCo2O4 with porous structure was prepared by co-precipitation method. • Flake-by-flake used in ZnCo2O4 was studied for the first time. • The as-prepared ZCO shows excellent electrochemical performances. • The preparation method has mild experiment conditions and high production rate. -- Abstract: A novel flake-by-flake ZnCo2O4 (ZCO) with porous nanostructure is prepared by a typical and facile co-precipitation method using oxalic acid as complex agent. XRD, SEM, and TEM analyses show the as-prepared ZCO nanoparticles have a high purity and a good crystallinity, and the ZCO nanoflakes with a thickness of 30–80 nm are composed of uniform ZCO nanocrystals with a diameter of 20–40 nm. The novel structure with enough free space is beneficial to improving the electrochemical performance. The as-prepared ZCO used as an anode material for lithium-ion batteries exhibits a high specific capacity of 1275 mA h/g at a current rate of 100 mA/g after 50 cycles, as well as a high power capability at elevated current rates, i.e., 1130 and 730 mA h/g at current rates of 500 and 3000 mA/g, respectively. It has a great prospect for the application of anode materials for lithium-ion batteries

  13. The capacity fading mechanism and improvement of cycling stability in MoS2-based anode materials for lithium-ion batteries

    Science.gov (United States)

    Shu, Haibo; Li, Feng; Hu, Chenli; Liang, Pei; Cao, Dan; Chen, Xiaoshuang

    2016-01-01

    Two-dimensional (2D) layered MoS2 nanosheets possess great potential as anode materials for lithium ion batteries (LIBs), but they still suffer from poor cycling performance. Improving the cycling stability of electrode materials depends on a deep understanding of their dynamic structural evolution and reaction kinetics in the lithiation process. Herein, thermodynamic phase diagrams and the lithiation dynamics of MoS2-based nanostructures with the intercalation of lithium ions are studied by using first-principles calculations and ab initio molecular dynamics simulations. Our results demonstrate that the continuous intercalation of Li ions induces structural destruction of 2H phase MoS2 nanosheets in the discharge process that follows a layer-by-layer dissociation mechanism. Meanwhile, the intercalation of Li ions leads to a structural transition of MoS2 nanosheets from the 2H to the 1T phase due to the ultralow transition barriers (~0.1 eV). We find that the phase transition can slow down the dissociation of MoS2 nanosheets during lithiation. The result can be applied to explain extensive experimental observation of the fast capacity fading of MoS2-based anode materials between the first and the subsequent discharges. To suppress the dissociation of MoS2 nanosheets in the lithiation process, we propose a strategy by constructing a sandwich-like graphene/MoS2/graphene structure that indicates high chemical stability, superior conductivity, and high Li-ion mobility in the charge/discharge process, implying the possibility to induce an improvement in the anode cycling performance. This work opens a new route to rational design layered transition-metal disulfide (TMD) anode materials for LIBs with superior cycling stability and electrochemical performance.Two-dimensional (2D) layered MoS2 nanosheets possess great potential as anode materials for lithium ion batteries (LIBs), but they still suffer from poor cycling performance. Improving the cycling stability of

  14. -Based Cermet Inert Anodes for Aluminum Electrolysis

    Science.gov (United States)

    Tian, ZhongLiang; Lai, YanQing; Li, ZhiYou; Chai, DengPeng; Li, Jie; Liu, YeXiang

    2014-11-01

    The new aluminum electrolysis technology based on inert electrodes has received much interest for several decades because of the environment and energy advantages. The key to realize this technique is the inert anode. This article presents China's recent developments of NiFe2O4-based cermet inert anodes, which include the optimization of material performance, the joint between the cermet inert anode and metallic bar, as well as the results of 20 kA pilot testing for a large-size inert anode group. The problems NiFe2O4-based cermet inert anodes face are also discussed.

  15. Effects of single and two stages anodizing on nonporous anodic alumina template at different potentials

    International Nuclear Information System (INIS)

    The porous anodic alumina has extensive applications as mold or template for filling the highly ordered patterned ID nanomaterials (semiconductors, magnetic nanowires etc.) and as a mask for nano dots of different materials. Pores in anodic alumina synthesized under appropriate conditions are self organized. Pore density, pore diameter, interpore distance may be changed through variation of different parameter such as anodic potential, choice of electrolyte, temperature and kind of pre-treatment. The porous anodic alumina has been synthesized by single and double stage anodizing at different potentials. The potentials used were 40V, 50V, 60V and 70V. By comparison of ordered pore formation under both the conditions, it has been found that pores formed in doubly anodized alumina are more ordered/organized than in singly anodized anodic alumina at same potential used for both type of synthesis. SEM images revealed that the pore density in the singly anodized alumina was greater than in doubly anodized alumina prepared under the same potential. Using the SEM image, the pore diameter in the case of doubly anodized alumina was found to be in the range of 50- 70 nm, whereas, for singly anodized alumina pore diameter was found to be in the range of 50-100 nm. Scanning electron Microscope images and electrochemical parameters showed that two stage anodizing is better than single stage anodizing to achieve highly ordered nanoporous alumina template. (author)

  16. Pulsed laser deposited Cr{sub 2}O{sub 3} nanostructured thin film on graphene as anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Khamlich, S., E-mail: skhamlich@gmail.com [UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, College of Graduate Studies, University of South Africa, Muckleneuk Ridge, PO Box 392, Pretoria (South Africa); Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West 7129, PO Box 722, Somerset West, Western Cape Province (South Africa); Nuru, Z.Y. [UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, College of Graduate Studies, University of South Africa, Muckleneuk Ridge, PO Box 392, Pretoria (South Africa); Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West 7129, PO Box 722, Somerset West, Western Cape Province (South Africa); Bello, A.; Fabiane, M.; Dangbegnon, J.K.; Manyala, N. [Department of Physics, SARChI Chair in Carbon Technology and Materials, Institute of Applied Materials, University of Pretoria, Pretoria (South Africa); Maaza, M. [UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, College of Graduate Studies, University of South Africa, Muckleneuk Ridge, PO Box 392, Pretoria (South Africa); Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West 7129, PO Box 722, Somerset West, Western Cape Province (South Africa)

    2015-07-15

    Graphical abstract: A different approach for the fabrication of an anode material system that comprises pulsed laser-deposited (PLD) Cr{sub 2}O{sub 3} grown on few layer graphene (FLG) by chemical vapor deposition (CVD) was used. The electrochemical performance of Cr{sub 2}O{sub 3} nanostructured thin film was improved by FLG, which make it a promising candidate for future lithium-ion batteries application. - Highlights: • Pulsed laser deposition technique was used to deposit Cr{sub 2}O{sub 3} on few-layer graphene (FLG). • FLG improved the electrochemical performance of Cr{sub 2}O{sub 3} nanostructured thin film. • Good stable cycle of Cr{sub 2}O{sub 3}/FLG/Ni electrode make it one of the promise anode materials for future lithium-ion batteries. - Abstract: Pulsed laser deposition technique was used to deposit Cr{sub 2}O{sub 3} nanostructured thin film on a chemical vapor deposited few-layer graphene (FLG) on nickel (Ni) substrate for application as anode material for lithium-ion batteries. The experimental results show that graphene can effectively enhance the electrochemical property of Cr{sub 2}O{sub 3}. For Cr{sub 2}O{sub 3} thin film deposited on Ni (Cr{sub 2}O{sub 3}/Ni), a discharge capacity of 747.8 mA h g{sup −1} can be delivered during the first lithiation process. After growing Cr{sub 2}O{sub 3} thin film on FLG/Ni, the initial discharge capacity of Cr{sub 2}O{sub 3}/FLG/Ni was improved to 1234.5 mA h g{sup −1}. The reversible lithium storage capacity of the as-grown material is 692.2 mA h g{sup −1} after 100 cycles, which is much higher than that of Cr{sub 2}O{sub 3}/Ni (111.3 mA h g{sup −1}). This study reveals the differences between the two material systems and emphasizes the role of the graphene layers in improving the electrochemical stability of the Cr{sub 2}O{sub 3} nanostructured thin film.

  17. Biomass carbon micro/nano-structures derived from ramie fibers and corncobs as anode materials for lithium-ion and sodium-ion batteries

    Science.gov (United States)

    Jiang, Qiang; Zhang, Zhenghao; Yin, Shengyu; Guo, Zaiping; Wang, Shiquan; Feng, Chuanqi

    2016-08-01

    Three-dimensional (3D) rod-like carbon micro-structures derived from natural ramie fibers and two-dimensional (2D) carbon nanosheets derived from corncobs have been fabricated by heat treatment at 700 °C under argon atomsphere. The structure and morphology of the as-obtained ramie fiber carbon (RFC) and corncob carbon (CC) were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) technique. The electrochemical performances of the biomass carbon-based anode in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) were investigated. When tested as anode material for lithium ion batteries, both the RFC microrods and CC nanosheets exhibited high capacity, excellent rate capability, and stable cyclability. The specific capacity were still as high as 489 and 606 mAhg-1 after 180 cycles when cycled at room temperature in a 3.0-0.01 V potential (vs. Li/Li+) window at current density of 100 mAg-1, respectively, which are much higher than that of graphite (375 mAhg-1) under the same current density. Although the anodes in sodium ion batteries showed poorer specific capability than that in lithium-ion batteries, they still achieve a reversible sodium intercalation capacity of 122 and 139 mAhg-1 with similar cycling stability. The feature of stable cycling performance makes the biomass carbon derived from natural ramie fibers and corncobs to be promising candidates as electrodes in rechargeable sodium-ion batteries and lithium-ion batteries.

  18. Preparation and electrochemical properties of core-shell carbon coated Mn–Sn complex metal oxide as anode materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ruixue [Key Laboratory of Lithium Battery Materials of Jiangsu Province, Institute of chemical power sources, Soochow University, Suzhou 215006 (China); Fang, Guoqing; Liu, Weiwei [Key Laboratory of Lithium Battery Materials of Jiangsu Province, Institute of chemical power sources, Soochow University, Suzhou 215006 (China); Changzhou Institute of Energy Storage Materials and Devices, Changzhou 213000 (China); Xia, Bingbo; Sun, Hongdan; Zheng, Junwei [Key Laboratory of Lithium Battery Materials of Jiangsu Province, Institute of chemical power sources, Soochow University, Suzhou 215006 (China); Li, Decheng, E-mail: lidecheng@suda.edu.cn [Key Laboratory of Lithium Battery Materials of Jiangsu Province, Institute of chemical power sources, Soochow University, Suzhou 215006 (China)

    2014-02-15

    In this study, we synthesized a carbon coated Mn–Sn metal oxide composite with core-shell structure (MTO@C) via a simple glucose hydrothermal reaction and subsequent carbonization approach. When the MTO@C composite was applied as an anode material for lithium-ion batteries, it maintained a reversible capacity of 409 mA h g{sup −1} after 200 cycles at a current density of 100 mA g{sup −1}. The uniformed and continuous carbon layer formed on the MTO nanoparticles, effectively buffered the volumetric change of the active material and increased electronic conductivity, which thus prolonged the cycling performance of the MTO@C electrode.

  19. Structural and microstructural characterization of tin(II oxide useful as anode material in lithium rechargeable batteries obtained from a different synthesis route at room temperature

    Directory of Open Access Journals (Sweden)

    Mario Alberto Macías

    2011-01-01

    Full Text Available Tin (II oxide has been proposed as potential anode material in lithium rechargeable batteries. Different methods to obtain such compound have been developed with relative difficulty due to the fact that Sn(II is easily oxidized to Sn(IV. We have applied a different methodology to synthesize SnO-romarchite by modifying the solvent nature of the controlled precipitation route using acetic acid and not water. Although the formation of Sn(IV oxide could not be completely avoided, X-ray diffraction analysis confirmed the synthesis of metastable tin(II oxide as major phase at room temperature. In depth analysis using Popa's model for Rietveld refinement allows to precise that the material corresponds to small and distorted crystallites, very anisotropic in size. SEM technique confirmed the microstructure is build of flower-like agglomerates of ~15 µm, in turn made of plate-like individual grains that remind the crystallite structure anisotropy.

  20. Facile synthesis and stable cycling ability of hollow submicron silicon oxide–carbon composite anode material for Li-ion battery

    International Nuclear Information System (INIS)

    Highlights: • Hollow submicron SiO2–carbon composite material was synthesized using Si4+-citrate chelation. • Composite material possessed a homogeneous distribution of SiO2 and carbon. • Composite electrode delivered ⩾600 mAh/g with a stable cycling stability. • This materials design and synthesis provides a useful platform for scalable production. - Abstract: Advanced SiO2–carbon composite anode active material for lithium-ion battery has been synthesized through a simple chelation of silicon cation with citrate in a glyme-based solvent. The resultant composite material demonstrates a homogeneous distribution of constituents over the submicron particles and a unique hollow spherical microstructure, which provides an enhanced electrical conductivity and better accommodation of volume change of silicon during electrochemical charge–discharge cycling, respectively. As a result, the composite electrode exhibits a high cycling stability delivering the capacity retention of 91% at the 100th cycle and discharge capacities of 662–602 mAh/g and coulombic efficiencies of 99.8%. This material synthesis is scalable and cost-effective in preparing various submicron or micron composite electrode materials

  1. Facile synthesis and stable cycling ability of hollow submicron silicon oxide–carbon composite anode material for Li-ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Joong-Yeon; Nguyen, Dan Thien [Department of Fine Chemical Engineering & Applied Chemistry, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Kang, Joon-Sup [Department of Energy Science and Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Song, Seung-Wan, E-mail: swsong@cnu.ac.kr [Department of Fine Chemical Engineering & Applied Chemistry, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Department of Energy Science and Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

    2015-06-05

    Highlights: • Hollow submicron SiO{sub 2}–carbon composite material was synthesized using Si{sup 4+}-citrate chelation. • Composite material possessed a homogeneous distribution of SiO{sub 2} and carbon. • Composite electrode delivered ⩾600 mAh/g with a stable cycling stability. • This materials design and synthesis provides a useful platform for scalable production. - Abstract: Advanced SiO{sub 2}–carbon composite anode active material for lithium-ion battery has been synthesized through a simple chelation of silicon cation with citrate in a glyme-based solvent. The resultant composite material demonstrates a homogeneous distribution of constituents over the submicron particles and a unique hollow spherical microstructure, which provides an enhanced electrical conductivity and better accommodation of volume change of silicon during electrochemical charge–discharge cycling, respectively. As a result, the composite electrode exhibits a high cycling stability delivering the capacity retention of 91% at the 100th cycle and discharge capacities of 662–602 mAh/g and coulombic efficiencies of 99.8%. This material synthesis is scalable and cost-effective in preparing various submicron or micron composite electrode materials.

  2. Self-discharge of LiSi and LiB anode materials%LiSi和LiB负极材料的自放电性能

    Institute of Scientific and Technical Information of China (English)

    袁光明; 高文秀; 李成; 赵小玲; 郑奕; 刘波

    2015-01-01

    The capacity decay occurs due to the self-discharge after activation in the molten salt electrolyte lithium batteries. Using LiF-LiCl-LiBr molten salts as electrolyte and FeS2 as cathode material, the lithium-silicon alloy and lithium-boron alloy as anode material to prepare single cells, which was then discharged at constant currents and 500℃. The working time of the single cells can be adjusted simply by varying the discharge current, the change of the available capacity is obtained. The working time and the measured capacity were analyzed by unary linear regression. The results show that the rate of the capacity loss is 40.6 C/min when lithium-silicon alloy is used as anode material, which is only 15.5 C/min when lithium-boron alloy is used as anode material.%熔盐电解质锂电池在激活后由于自放电导致容量发生衰减,采用LiF-LiCl-LiBr低温共熔盐电解质,以二硫化铁为正极材料,分别以锂硅合金和锂硼合金作为负极材料制备单体电池,在500℃的温度下进行恒流放电试验。通过改变单体电池的工作电流可控制电池放电时间,并得到单体电池在经历不同工作时间后获得的可利用电容量。并将单体电池的工作时间和可利用电容量经一次线性回归分析。结果发现,使用锂硅合金作为负极材料时,电池的容量衰减率为40.6 C/min;而使用锂硼合金作为负极材料时,电池的容量衰减率仅为15.5 C/min。

  3. 锂离子电池用硅基材料的研究进展%Research progress of silicon material as anode for lithium-ion batteries

    Institute of Scientific and Technical Information of China (English)

    李涛; 杨娟玉; 卢世刚

    2012-01-01

    锂离子电池硅基负极材料以其较高的理论比容量(4 200 nAh/g),成为最具吸引力的新一代负极材料.但硅基负极材料较差的循环性能和较大的首次不可逆容量损失导致其商业化应用受科限制.研究者采取了各种方法来克服硅基材料在嵌脱锂过程中较大的体积变化对电极结构的破坏,从而获得了较好的容量保持率和循环性能,其中包括纳米化、复合化和薄膜化等材料体系的改性,选择不同的粘接剂、导电剂等电极制备方法的改进,以及选择不同电解液和控制电压窗口等电池实际应用方面的措施.主要介绍了近年来硅基负极改性方法方面的研究进展,探讨了硅基材料应用中的问题及可能的解决方法.%Silicon materials are attractive candidates for the next generation of fithium-ion batteries due to their high theoretical specific capacities (4 200 mAh/g).However,the commercial use of silicon anodes has been hindered to date by their low cycle life and high initial capacity loss.To overcome the damage of the electrode from the targe volume change and thus obtain better capacity retention and cycle life for Si anodes,various approaches have been used: using nano-partictes,forming multiphase composites,fabricating thin film electrodes and alloys,using selected binders and electrolyte,operating vottage control,et al.Here,the methodologies adopted for reducing the capacity fade observed in silicon-based anodes were reviewed,the challenges that remained in using silicon and silicon-based anodes were discussed,and the possible approaches for overcoming them were proposed.

  4. Improving the electrochemical properties of Al, Zr Co-doped Li4Ti5O12 as a lithium-ion battery anode material

    International Nuclear Information System (INIS)

    Li4Ti5O12 and Al3+, Zr4+ co-doped Li(4-x/3)AlxTi(5-5x/3)ZrxO12 (x = 0.01, 0.05, 0.1, 0.15, 0.2) were synthesized at 950 .deg. C via a solid state reaction by using rutile TiO2, Li2CO3, and Al2O3 as precursors for the anode material of a lithium-ion battery. The average particle sizes of Li(4-x/3)AlxTi(5-5x/3)ZrxO12 (x = 0, 0.01, 0.05, 0.1, 0.15, 0.2) range from 700 to 1200 nm. The particle sizes of pure Li4Ti5O12 and Al3+, Zr4+ co-doped Li4Ti5O12 were not obviously different, but did result in a shift in the (111) peak in X-ray diffraction. Li(4-x/3)AlxTi(5-5x/3)ZrxO12 (x = 0.01) exhibits an excellent rate capability with a reversible capacity of 127.7 mAh/g at a 5 C-rate and even 113.1 mAh/g at a 10 C-rate. The capacity retention was improved remarkably compared to that for an undoped anode when discharged at a high C- rate.

  5. Effect of graphene nanosheet addition on the electrochemical performance of anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    The structure and electronic properties of graphene nanosheet (GNS) render it a promising conducting agent in a lithium-ion battery. A graphite electrode loaded with GNS exhibits superior electrochemical properties including higher rate performance, increased specific capacity and better cycle performance compared with that obtained by adding the traditional conducting agent-acetylene black. The high-quality sp2 carbon lattice, quasi-two-dimensional crystal structure and high aspect ratio of GNS provide the basis for a continuous conducting network to counter the decrease in electrode conductivity with increasing number of cycles, and guarantee efficient and fast electronic transport throughout the anode. Effects of GNS loading content on the electrochemical properties of graphite electrode are investigated and results indicate that the amount of conductive additives needed is decreased by using GNS. The kinetics and mechanism of lithium-storage for a GNS-loaded electrode are explored using a series of electrochemical testing techniques.

  6. Facile scalable synthesis of Co{sub 3}O{sub 4}/carbon nanotube hybrids as superior anode materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Zhiguo; Xu, Weiwei [Key Lab of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, and the College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China); Huang, Tao [Department of Chemistry, Fudan University, Shanghai 210024 (China); Li, Maolin; Wang, Wanren; Liu, Yanping; Mao, Chaochao; Meng, Fanli; Wang, Mengjiao [Key Lab of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, and the College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China); Cheng, Minghai [Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences (China); Yu, Aishui [Department of Chemistry, Fudan University, Shanghai 210024 (China); Guo, Xiaohui, E-mail: guoxh2009@nwu.edu.cn [Key Lab of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, and the College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China)

    2013-10-15

    Graphical abstract: Co{sub 3}O{sub 4}/MWCNT hybrids were synthesized via strong ultra-sonication assisted shaking processes. The resultant samples as anode electrode display enhanced cycling performance and rate capability compared with pure Co{sub 3}O{sub 4} particle. - Highlights: • Co{sub 3}O{sub 4}/MWCNT hybrids were synthesized via ultra-sonication assisted shaking process. • The resulting Co{sub 3}O{sub 4} nanoparticles are highly dispersed onto MWCNT network backbone. • Co{sub 3}O{sub 4}/MWCNT hybrid displays highly enhanced lithium storage properties. • The present synthetic approach is facile, controllable, and scalable. - Abstract: In this report, Co{sub 3}O{sub 4}/multiple-wall carbon nanotube (MWCNT) hybrid materials were synthesized via strong ultrasonication-assisted shaking and magnetic stirring processes. The prepared samples were well characterized by utilizing powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy techniques. Results indicated that the resulting Co{sub 3}O{sub 4} nanoparticles were highly dispersed in the MWCNT network backbone and further form Co{sub 3}O{sub 4}/MWCNT hybrid materials. The obtained Co{sub 3}O{sub 4}/MWCNT hybrids can be employed as anode electrode in Lithium-ion batteries and deliver as high as discharge capacity of 1250 mA h g{sup −1} at a current density of 0.2 C, additionally, 81% of the discharge capacity for sample 2 with 20 wt.% MWCNT loading could be retained after 70 cycles, which could be associated with the specific hybrid structure of the electrode as well as the addition of MWCNT. Most importantly, the present synthetic approach is facile, controllable, and scalable, which allowing it more easily adapted to prepare other hybrid materials with specific architectures.

  7. Synthesis of One Dimensional Li2MoO4 Nanostructures and Their Electrochemical Performance as Anode Materials for Lithium-ion Batteries

    International Nuclear Information System (INIS)

    Highlights: • One dimensional Li2MoO4 nanostructures including nanorods and nanotubes have been successfully fabricated via a simple sol-gel method firstly. • Possible crystal formation mechanisms are proposed for these one dimensional Li2MoO4 nanostructures. • These one dimensional Li2MoO4 nanostructure electrode materials present outstanding rate abilities and cycle capabilities in electrochemical performance compared to the carbon-free powder sample when evaluated as anode materials for Lithium-ion batteries. • The carbon-coated Li2MoO4 nanotube electrode improves the charging/discharging capacities of graphite even after applying 60 cycles at very high current density. - Abstract: One dimensional Li2MoO4 nanostructures including nanorods and nanotubes have been successfully fabricated via a simple sol-gel method adding Li2CO3 and MoO3 powders into distilled water with citric acid as an assistant agent and carbon source. Our experimental results show that the formation of the one dimensional nanostructure morphology is evaporation and crystallization process with self-adjusting into a rod-like hexagonal cross-section structure, while the citric acid played an important role during the formation of Li2MoO4 nanotubes under the acidic environment by capping, stabilizing the {1010} facet of Li2MoO4 structure and controlling the concentration of H+ (pH value) of the aqueous solution. Finally, basic electrochemical performance of these one dimensional Li2MoO4 nanostructures including nanorods and nanotubes evaluated as anode materials for lithium-ion batteries (LIBs) are discussed, for comparison, the properties of carbon-free powder sample synthesized by solid-state reaction are also displayed. Experimental results show that different morphology and carbon-coating on the surface have an important influence on electrochemical performance

  8. A new gridding cyanoferrate anode material for lithium and sodium ion batteries: Ti0.75Fe0.25[Fe(CN)6]0.96·1.9H2O with excellent electrochemical properties

    Science.gov (United States)

    Sun, Xin; Ji, Xiao-Yang; Zhou, Yu-Ting; Shao, Yu; Zang, Yong; Wen, Zhao-Yin; Chen, Chun-Hua

    2016-05-01

    A novel air-stable titanium hexacyanoferrate (Ti0.75Fe0.25[Fe(CN)6]0.96·1.9H2O) with a cubic structure is synthesized simply by a solution precipitation method, which is first demonstrated to be a scalable, low-cost anode material for lithium-ion batteries exhibiting high capacity, long cycle life and good rate capability. Nevertheless, it has a low capacity of about 100 mAh g-1 as an anode material for sodium-ion batteries.

  9. Novel synthetic approach for 1, 4-dihydroxyanthraquinone and the development of its Lithiated salts as anode material for aqueous rechargeable Lithium-ion batteries

    KAUST Repository

    Gurukar, Suresh Shivappa

    2015-08-17

    The influence of organic electrode materials in the field of lithium ion battery is becoming a keen interest for the present generation scientists. Here we are reporting a novel method of synthesis of electrode material by the combination of sono-chemical and thermal methods. The advantages of organic active material towards lithium ion battery are of core interest of this study. The structural confirmations are by FT-IR, 1H NMR, MALDI-TOF Mass Spectroscopy and powder XRD data. The electrochemical properties of Lithiated-1,4-dihydroxyanthraquinone were studied using electrochemical-techniques such as Cyclic Voltammetry, Galvanostatic Cyclic Potential Limitation and Potentiostatic Electrochemical Impedance Spectroscopy. The satisfactory results towards stability of active species in the aqueous media, reasonable discharge capacity with 0.9 V average voltages and agreeable cycling performance during charge-discharge process with reproducibility are achieved. For the construction of the full cell, the anode material was coupled with the LiNi1/3Co1/3Mn1/3O2 as a cathode material.

  10. Unique 1D Co3O4 crystallized nanofibers with (220) oriented facets as high-performance lithium ion battery anode material

    Science.gov (United States)

    Tan, Yanli; Gao, Qiuming; Li, Zeyu; Tian, Weiqian; Qian, Weiwei; Yang, Chunxiao; Zhang, Hang

    2016-01-01

    A novel one-step hydrothermal and calcination strategy was developed to synthesize the unique 1D oriented Co3O4 crystal nanofibers with (220) facets on the carbon matrix derived from the natural, abundant and low cost wool fibers acting as both carbon precursor and template reagent. The resultant W2@Co3O4 nanocomposite exhibited very high specific capacity and favorable high-rate capability when used as anode material of lithium ion battery. The high reversible Li+ ion storage capacity of 986 mAh g−1 was obtained at 100 mA g−1 after 150 cycles, higher than the theoretical capacity of Co3O4 (890 mAh g−1). Even at the higher current density of 1 A g−1, the electrode could still deliver a remarkable discharge capacity of 720 mAh g−1 over 150 cycles. PMID:27217201

  11. Self-assembled graphene-wrapped SnO{sub 2} nanotubes nanohybrid as a high-performance anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ping, E-mail: zjuwuping@njnu.edu.cn; Xu, Xiali; Zhu, Qingyun; Zhu, Xiaoshu; Tang, Yawen; Zhou, Yiming, E-mail: zhouyiming@njnu.edu.cn; Lu, Tianhong

    2015-03-25

    Highlights: • SnO{sub 2}-NTs/G nanohybrid prepared via a facile Sn-nanorod-templated self-assembly route. • 3D interconnected network of SnO{sub 2} nanotubes wrapped and bridged by graphene matrix. • Superior lithium storage performance by virtue of its unique structural features. - Abstract: Herein, a novel type of graphene-wrapped SnO{sub 2} nanotubes (SnO{sub 2}-NTs/G) nanohybrid has been designed and constructed through a facile Sn-nanorod-templated self-assembly approach. The as-prepared SnO{sub 2}-NTs/G nanohybrid has been utilized as an anode material in lithium-ion batteries, and demonstrates remarkable cycling stability, high reversible capacities, and rate capability by virtue of its unique structural features.

  12. Self-assembled three-dimensional hierarchical NiO nano/microspheres as high-performance anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Highlights: • 3D hierarchical NiO porous nano/microspheres were prepared via a hydrothermal route. • Loose NiO microsphere is composed of a large number of cross-linked nanoparticles. • A possible self-assembly mechanism is illustrated in detail. • High specific capacity, good cycleability and superior rate-capability are achieved. - Abstract: Self-assembled three-dimensional hierarchical NiO nano/microspheres were fabricated via a hydrothermal route. The obtained NiO presents a micro-sized porous spherical morphology which is composed of a large number of primary NiO nanoparticles linked together with an ordered fashion. As anode material for lithium ion batteries, NiO nano/microspheres exhibit stable reversible capacity of over 700 mAh g−1 and good rate capability. The superior electrochemical performance could be attributed to the merits of the unique three-dimensional hierarchical porous nano/microstructure

  13. Persistent cyclestability of carbon coated Zn–Sn metal oxide/carbon microspheres as highly reversible anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Development of high-capacity anode materials equipped with strong cyclestability is a great challenge for use as practical electrode for high-performance lithium-ion rechargeable battery. In this study, we synthesized a carbon coated Zn–Sn metal nanocomposite oxide and carbon spheres (ZTO@C/CSs) via a simple glucose hydrothermal reaction and subsequent carbonization approach. The carbon coated ZTO/carbon microspheres composite maintained a reversible capacity of 680 mAh g−1 after 345 cycles at a current density of 100 mA g−1, and furthermore the cell based on the composite exhibited an excellent rate capability of 470 mAh g−1 even when the cell was cycled at 2000 mA g–1. The thick carbon layer formed on the ZTO nanoparticles and carbon spheres effectively buffered the volumetric change of the particles, which thus prolonged the cycling performance of the electrodes

  14. La0.4Sr0.6Ti1-xMnxO3-d Perovskites as New Anode Materials for Solid Oxide Fuel Cells

    OpenAIRE

    Fu, Q. X.; Tietz, F.; Stöver, D.

    2006-01-01

    Perovskite oxides, La0.4Sr0.6Ti1-xMnxO3-delta (x=0, 0.2, 0.4, 0.6), have been investigated in the search for new solid oxide fuel cell (SOFC) anode materials. La0.4Sr0.6Ti0.4Mn0.6O3-delta (LSTM4646) shows an electrical conductivity of 22.6 S/cm in air and 1.5 S/cm in wet Ar/4% H-2 [p(O-2)approximate to 10(-18) bar] at 810 degrees C. It is thermally and chemically compatible with yttria-stabilized zirconia (YSZ) electrolytes. Three processes govern the electrochemical performance of LSTM4646/Y...

  15. Facile Synthesis of Mn-Doped ZnO Porous Nanosheets as Anode Materials for Lithium Ion Batteries with a Better Cycle Durability.

    Science.gov (United States)

    Wang, Linlin; Tang, Kaibin; Zhang, Min; Xu, Jingli

    2015-12-01

    Porous Zn1 - x Mn x O (x = 0.1, 0.2, 0.44) nanosheets were prepared by a low-cost, large-scale production and simple approach, and the applications of these nanosheets as an anode material for Li-ion batteries (LIBs) were explored. Electrochemical measurements showed that the porous Zn0.8Mn0.2O nanosheets still delivered a stable reversible capacity of 210 mA h g(-1) at a current rate of 120 mA g(-1) up to 300 cycles. These results suggest that the facile synthetic method of producing porous Zn0.8Mn0.2O nanostructure can realize a better cycle durability with stable reversible capacity. PMID:26138451

  16. Synthesis and electrochemical performance of cable-like copper vanadates/polypyrrole nanobelts as anode materials for lithium-ion batteries

    Science.gov (United States)

    Zhang, Shaoyan; Hou, Menghua; Hou, Linlin; Lu, Min

    2016-08-01

    Cable-like CuV2O6/polypyrrole (CVO/PPy) nanobelts have been synthesized via in-situ oxidative polymerization of pyrrole monomers on the surface of hydrothermally synthesized α-CuV2O6 (CVO) nanobelts. The microscope analysis revealed that the diameter of cable-like CVO/PPy nanobelts focused on 80-110 nm and the shell thickness was about 10-30 nm. The electrochemical properties of the cable-like CVO/PPy nanobelts as anode materials were systematically investigated and compared with bare α-CuV2O6 nanobelts. It was found that the electrochemical performance of the CVO/PPy nanobelts was significantly enhanced. The results suggest that the conductive PPy nanolayer coating help to preserve high capacity, maintain high electrochemical stability, and reduce charge transfer resistance during cycling performance.

  17. Unique 1D Co3O4 crystallized nanofibers with (220) oriented facets as high-performance lithium ion battery anode material.

    Science.gov (United States)

    Tan, Yanli; Gao, Qiuming; Li, Zeyu; Tian, Weiqian; Qian, Weiwei; Yang, Chunxiao; Zhang, Hang

    2016-01-01

    A novel one-step hydrothermal and calcination strategy was developed to synthesize the unique 1D oriented Co3O4 crystal nanofibers with (220) facets on the carbon matrix derived from the natural, abundant and low cost wool fibers acting as both carbon precursor and template reagent. The resultant W2@Co3O4 nanocomposite exhibited very high specific capacity and favorable high-rate capability when used as anode material of lithium ion battery. The high reversible Li(+) ion storage capacity of 986 mAh g(-1) was obtained at 100 mA g(-1) after 150 cycles, higher than the theoretical capacity of Co3O4 (890 mAh g(-1)). Even at the higher current density of 1 A g(-1), the electrode could still deliver a remarkable discharge capacity of 720 mAh g(-1) over 150 cycles. PMID:27217201

  18. A ternary phased SnO2-Fe2O3/SWCNTs nanocomposite as a high performance anode material for lithium ion batteries

    Institute of Scientific and Technical Information of China (English)

    Wangliang Wu; Yi Zhao; Jiaxin Li; Chuxin Wu; Lunhui Guan

    2014-01-01

    A new SnO2-Fe2O3/SWCNTs (single-walled carbon nanotubes) ternary nanocomposite was first synthesized by a facile hydrothermal ap-proach. SnO2 and Fe2O3 nanoparticles (NPs) were homogeneously located on the surface of SWCNTs, as confirmed by X-ray diffraction (XRD), transmission electron microscope (TEM) and energy dispersive X-ray spectroscopy (EDX). Due to the synergistic effect of different components, the as synthesized SnO2-Fe2O3/SWCNTs composite as an anode material for lithium-ion batteries exhibited excellent electro-chemical performance with a high capacity of 692 mAh·g-1 which could be maintained after 50 cycles at 200 mA·g-1. Even at a high rate of 2000 mA·g-1, the capacity was still remained at 656 mAh·g-1.

  19. High capacity and good cycling stability of multi-walled carbon nanotube/SnO2 core-shell structures as anode materials of lithium-ion batteries

    International Nuclear Information System (INIS)

    The multi-walled carbon nanotube/SnO2 core-shell structures were fabricated by a wet chemical route. The electrochemical performance of the core-shell structures as anode materials of lithium-ion batteries was investigated. The initial discharge capacity and reversible capacity are up to 1472.7 and 1020.5 mAh g-1, respectively. Moreover, the reversible capacity still remains above 720 mAh g-1 over 35 cycles, and the capacity fading is only 0.8% per cycle. Such high capacities and good cyclability are attributed to SnO2 network structures, excellent mechanical property and good electrical conductivity of the multi-walled carbon nanotubes.

  20. Synthesis of dandelion-like TiO2 microspheres as anode materials for lithium ion batteries with enhanced rate capacity and cyclic performances

    Science.gov (United States)

    Yi, Jin; Liu, Yan-lin; Wang, Yuan; Li, Xiao-ping; Hu, She-jun; Li, Wei-shan

    2012-11-01

    Dandelion-like TiO2 microspheres consisting of numerous rutile single-crystalline nanorods were synthesized for the first time by a hydrothermal method. Their crystal structure, morphology and electrochemical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and galvanostatic charge and discharge tests. The results show that the synthesized TiO2 microspheres exhibit good rate and cycle performances as anode materials of lithium ion batteries. It can be found that the dandelion-like structure provides a larger specific surface area and the single-crystalline nanorod provides a stable structure and fast pathways for electron and lithium ion transport, which contribute to the rate and cycle performances of the battery.

  1. Cerium oxide coated anodes for aluminum electrowinning: Topical report, October 1, 1986-June 30, 1987

    Energy Technology Data Exchange (ETDEWEB)

    Walker, J. K.

    1987-12-01

    Because of the cost of building and maintaining a carbon anode plant and the energy penalties associated with the use of carbon anodes in the production of aluminum, the use of inert anodes has long been proposed. Various cermet anodes have been investigated. In this paper, tests on a material, cerium oxyfluoride (CEROX), deposited in situ as an anode, are reported. (JDH)

  2. {alpha}-Fe{sub 2}O{sub 3}-CNSs nanocomposites as superior anode materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Shao Jin; Zhang Jingxian; Jiang Jinjin [Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041 (China); Graduate University of Chinese Academy of Sciences, Beijing 100039 (China); Zhou Gumin [Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041 (China); Qu Meizhen, E-mail: mzhqu@cioc.ac.cn [Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041 (China)

    2011-08-01

    Highlights: > The nanocomposite of {alpha}-Fe{sub 2}O{sub 3}-CNSs has been successfully prepared and applied as anode of Li-ion batteries. > The {alpha}-Fe{sub 2}O{sub 3}/CNSs weight ratio has a crucial effect on the electrochemical performance of {alpha}-Fe{sub 2}O{sub 3}-CNSs. > Enhancing the amount of {alpha}-Fe{sub 2}O{sub 3} in nanocomposite would make the increase ofspecific capacity, but led to the degradation of cyclic stability and rate capability. > The most appropriate amount of {alpha}-Fe{sub 2}O{sub 3} in nanocomposite is 20 wt%. - Abstract: The nanocomposite of hematite-carbon nanosprings ({alpha}-Fe{sub 2}O{sub 3}-CNSs) was synthesized by simple precipitation and following heat treatment, in which the amount of {alpha}-Fe{sub 2}O{sub 3} can be easily controlled by changing the synthesis conditions. Thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electronic microscopy (SEM), Brunau-Emmertt-Teller (BET), and X-ray photoelectron spectroscopy (XPS) were employed to characterize the as-synthesized nanocomposite. When applied as anode in Li-ion batteries (LIBs), the effect of {alpha}-Fe{sub 2}O{sub 3}/CNSs weight ratio on electrochemical performance of {alpha}-Fe{sub 2}O{sub 3}-CNSs nanocomposite has been researched. Enhancing the amount of {alpha}-Fe{sub 2}O{sub 3} in nanocomposite would make the increase of specific capacity, but led to the degradation of cyclic stability and rate capability. The electrode of S-FeC (with weight ratio of CNSs/{alpha}-Fe{sub 2}O{sub 3} about 4:1) could deliver a charge capacity of 527.6 mAh g{sup -1}at 0.2 C with excellent cyclability (96.9% capacity retention after 50 cycles), and retained 343.3 mAh g{sup -1}even at the rate of 5.0 C. In comparison with pure CNSs and {alpha}-Fe{sub 2}O{sub 3}, the improved cycling performance, specific capacity and rate capability of S-FeC should be mainly attributed to the combined effects of uniformly dispersed nanosized {alpha}-Fe{sub 2}O{sub 3} particles and the

  3. Designed hybrid nanostructure with catalytic effect: beyond the theoretical capacity of SnO2 anode material for lithium ion batteries

    Science.gov (United States)

    Wang, Ye; Huang, Zhi Xiang; Shi, Yumeng; Wong, Jen It; Ding, Meng; Yang, Hui Ying

    2015-01-01

    Transition metal cobalt (Co) nanoparticle was designed as catalyst to promote the conversion reaction of Sn to SnO2 during the delithiation process which is deemed as an irreversible reaction. The designed nanocomposite, named as SnO2/Co3O4/reduced-graphene-oxide (rGO), was synthesized by a simple two-step method composed of hydrothermal (1st step) and solvothermal (2nd step) synthesis processes. Compared to the pristine SnO2/rGO and SnO2/Co3O4 electrodes, SnO2/Co3O4/rGO nanocomposites exhibit significantly enhanced electrochemical performance as the anode material of lithium-ion batteries (LIBs). The SnO2/Co3O4/rGO nanocomposites can deliver high specific capacities of 1038 and 712 mAh g−1 at the current densities of 100 and 1000 mA g−1, respectively. In addition, the SnO2/Co3O4/rGO nanocomposites also exhibit 641 mAh g−1 at a high current density of 1000 mA g−1 after 900 cycles, indicating an ultra-long cycling stability under high current density. Through ex-situ TEM analysis, the excellent electrochemical performance was attributed to the catalytic effect of Co nanoparticles to promote the conversion of Sn to SnO2 and the decomposition of Li2O during the delithiation process. Based on the results, herein we propose a new method in employing the catalyst to increase the capacity of alloying-dealloying type anode material to beyond its theoretical value and enhance the electrochemical performance. PMID:25776280

  4. Anatase-TiO{sub 2}/CNTs nanocomposite as a superior high-rate anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jinlong [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); Feng, Haibo; Jiang, Jianbo [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Qian, Dong, E-mail: qiandong6@vip.sina.com [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); Li, Junhua; Peng, Sanjun [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Liu, Youcai, E-mail: liuyoucai@126.com [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China)

    2014-08-01

    Highlights: • Anatase-TiO{sub 2}/CNTs nanocomposite was prepared by a facile and scalable hydrolysis route. • The composite exhibits super-high rate capability and excellent cycling stability for LIBs. • The nanocomposite shows great potential as a superior anode material for LIBs. - Abstract: Anatase-TiO{sub 2}/carbon nanotubes (CNTs) with robust nanostructure is fabricated via a facile two-step synthesis by ammonia water assisted hydrolysis and subsequent calcination. The as-synthesized nanocomposite was characterized employing X-ray powder diffraction, Fourier transform infrared spectrophotometry, Raman spectrophotometry, thermal gravimetric analysis, transmission electron microscopy, high-resolution transmission electron microscopy and selected area electronic diffraction, and its electrochemical properties as an anode material for lithium-ion batteries (LIBs) were investigated by cyclic voltammetry, galvanostatic discharge/charge test and electrochemical impendence spectroscopy. The results show that the pure anatase TiO{sub 2} nanoparticles with diameters of about 10 nm are uniformly distributed on/among the CNTs conducting network. The as-synthesized nanocomposite exhibits remarkably improved performances in LIBs, especially super-high rate capability and excellent cycling stability. Specifically, a reversible capacity as high as 92 mA h g{sup −1} is achieved even at a current density of 10 A g{sup −1} (60 C). After 100 cycles at 0.1 A g{sup −1}, it shows good capacity retention of 185 mA h g{sup −1} with an outstanding coulombic efficiency up to 99%. Such superior Li{sup +} storage properties demonstrate the reinforced synergistic effects between the nano-sized TiO{sub 2} and the interweaved CNTs network, endowing the nanocomposite with great application potential in high-power LIBs.

  5. Designed hybrid nanostructure with catalytic effect: beyond the theoretical capacity of SnO2 anode material for lithium ion batteries

    Science.gov (United States)

    Wang, Ye; Huang, Zhi Xiang; Shi, Yumeng; Wong, Jen It; Ding, Meng; Yang, Hui Ying

    2015-03-01

    Transition metal cobalt (Co) nanoparticle was designed as catalyst to promote the conversion reaction of Sn to SnO2 during the delithiation process which is deemed as an irreversible reaction. The designed nanocomposite, named as SnO2/Co3O4/reduced-graphene-oxide (rGO), was synthesized by a simple two-step method composed of hydrothermal (1st step) and solvothermal (2nd step) synthesis processes. Compared to the pristine SnO2/rGO and SnO2/Co3O4 electrodes, SnO2/Co3O4/rGO nanocomposites exhibit significantly enhanced electrochemical performance as the anode material of lithium-ion batteries (LIBs). The SnO2/Co3O4/rGO nanocomposites can deliver high specific capacities of 1038 and 712 mAh g-1 at the current densities of 100 and 1000 mA g-1, respectively. In addition, the SnO2/Co3O4/rGO nanocomposites also exhibit 641 mAh g-1 at a high current density of 1000 mA g-1 after 900 cycles, indicating an ultra-long cycling stability under high current density. Through ex-situ TEM analysis, the excellent electrochemical performance was attributed to the catalytic effect of Co nanoparticles to promote the conversion of Sn to SnO2 and the decomposition of Li2O during the delithiation process. Based on the results, herein we propose a new method in employing the catalyst to increase the capacity of alloying-dealloying type anode material to beyond its theoretical value and enhance the electrochemical performance.

  6. Preparation of Carbon-Encapsulated ZnO Tetrahedron as an Anode Material for Ultralong Cycle Life Performance Lithium-ion Batteries

    International Nuclear Information System (INIS)

    Highlights: • A novel architecture of 3D carbon framework to encapsulate ZnO nanocrystals was prepared. • The ZnO@C exhibits ultralong cycle life and high specific capacity when was used as anode. • The in situ carbonization leads to a strong connection between the carbon and ZnO. - ABSTRACT: In this paper we report a novel architecture of three-dimension (3D) carbon framework to encapsulate tetrahedron ZnO nanocrystals that serves as an anode material for lithium-ion batteries (LIBs). The ZnO@C composites are prepared via a simple internal-reflux method combined with subsequent calcination in argon. The amorphous carbon is formed on the surface of the ZnO crystals by in situ carbonization of the surfactant, which leads to a strong connection between the carbon framework and the active materials and guarantees faster charge transfer on the electrode. The ZnO crystal calcined at 500°C (ZnO@C-5) possesses regular tetrahedron shape with a side length of 150-200 nm and all of them are uniformly anchored among the network of amorphous carbon. The developed ZnO@C structures not only improve the electronic conductivity of the electrode, but they also offer a larger volume expansion of ZnO during cycling. As a result, the ZnO@C-5 demonstrates a higher reversible capacity, ultralong cycle life and better rate capability than that of the ZnO@C-7 and pure ZnO crystals. After 300 cycles, the ZnO@C-5 demonstrates a high capacity of 518 mAhg−1 at a current density of 110.7 mAg−1. Moreover, this simple approach prepared the 3D composites architecture could shed light on the design and synthesis of other transition metal oxides for energy storage

  7. CuLi2Sn and Cu2LiSn: Characterization by single crystal XRD and structural discussion towards new anode materials for Li-ion batteries

    International Nuclear Information System (INIS)

    The stannides CuLi2Sn (CSD-427095) and Cu2LiSn (CSD-427096) were synthesized by induction melting of the pure elements and annealing at 400 °C. The phases were reinvestigated by X-ray powder and single-crystal X-ray diffractometry. Within both crystal structures the ordered CuSn and Cu2Sn lattices form channels which host Cu and Li atoms at partly mixed occupied positions exhibiting extensive vacancies. For CuLi2Sn, the space group F-43m. was verified (structure type CuHg2Ti; a=6.295(2) Å; wR2(F²)=0.0355 for 78 unique reflections). The 4(c) and 4(d) positions are occupied by Cu atoms and Cu+Li atoms, respectively. For Cu2LiSn, the space group P63/mmc was confirmed (structure type InPt2Gd; a=4.3022(15) Å, c=7.618(3) Å; wR2(F²)=0.060 for 199 unique reflections). The Cu and Li atoms exhibit extensive disorder; they are distributed over the partly occupied positions 2(a), 2(b) and 4(e). Both phases seem to be interesting in terms of application of Cu–Sn alloys as anode materials for Li-ion batteries. - Highlights: • First single crystal investigation of CuLi2Sn and Cu2LiSn clarifies contradictions from literature. • Lithium atoms are ordered in channels, which is interesting for application as anode materials for lithium ion batteries. • Structural relationships to binary Cu–Sn-phases are shown. • Close structural relationship between both ternary phases exists

  8. L-Cysteine-Assisted Synthesis of Cubic Pyrite/Nitrogen-Doped Graphene Composite as Anode Material for Lithium-ion Batteries

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • We have demonstrated a new and general strategy to synthesize FeS2/nitrogen-doped graphene composite by an L-cysteine-assisted solution-phase method. • Cubic FeS2 particles are uniformly distributed on the surface of nitrogen-doped graphene nanosheets. • Nitrogen-doped graphene nanosheets can not only prevent the cubic FeS2 particles from aggregating, but also accommodate the volume change of cubic FeS2 particles during cycling. • We have demonstrated that electrochemical performance of cubic FeS2 particles significantly improve with nitrogen-doped graphene. - Abstract: Transition-metal sulfides have received increasing attention as electrode materials for high-performance Lithium-ion Batteries (LIBs). However, most of them are suffering from poor cycling stability and rate capability. Herein we report a new and facile strategy for synthesizing FeS2/nitrogen-doped graphene (FeS2/N-G) composite which shows improved electrochemical performance as an anode material for LIBs. The as-prepared FeS2/N-G (1:2, molar ratio) composite exhibits reversible discharge and charge capacities of 979 and 920 mAh g−1, respectively, with good cycling performance and rate capability. SEM and TEM results show that the cubic FeS2 are uniformly distributed on the surface of the nitrogen-doped graphene nanosheets (N-GNS) in the composite. The superior electrochemical performance of FeS2/N-G composite as LIBs anode is attributed to their robust composite structure and the synergistic effects between cubic FeS2 and N-GNS. This synthesis approach could open up new opportunities in the design and fabrication of energy storage devices

  9. Li and Na storage behavior of bowl-like hollow Co3O4 microspheres as an anode material for lithium-ion and sodium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • A unique bowl-like hollow spherical Co3O4 structure is prepared through a simple, low-cost and mass-yield method. • Such a bowl-like hollow Co3O4 microsphere demonstrates extraordinary rate and cycling performance for Li-storage. • The sodium-storage behavior of Co3O4 is investigated for the first time. - Abstract: Bowl-like hollow Co3O4 microspheres are prepared via a simple and low-cost route by thermally treating Co-containing resorcinol-formaldehyde composites gel in air. Scanning electron microscopy, transmission electron microscope and N2 adsorption-desorption measurements demonstrate that these bowl-like hollow Co3O4 microspheres are composed of hollow inner cavities and outer shell walls (70 nm thickness), on which a considerable amount of mesopores centered around 5-17 nm size are distributed. When employed as the anode material for lithium-ion batteries, these bowl-like hollow Co3O4 microspheres exhibit extraordinary cycling performance (111% retention after 50 cycles owing to capacity rise), fairly high rate capacity (650 mAh g−1 at 5 C) and enhanced lithium storage capacity. Meanwhile, the Na-storage behavior of Co3O4 as an anode material of Na-ion batteries is initially investigated based on such a hollow structure and it exhibits similar feature of discharge/charge profiles and a high initial discharge capacity but relatively moderate capacity retention compared with the Li-storage performance

  10. Enhanced electrochemical performance of CoMoO4 nanorods/reduced graphene oxide as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Facile, green and large scale synthesis method. • CoMoO4 nanorods possess small diameter (about 40∼60 nm in width and 1.5∼2 μm in length) and uniformly distributed on reduced graphene oxide. • CoMoO4 nanorods/reduced graphene oxide composite delivered high initial discharge capacity (1496 mA h g−1 at a current density of 100 mA g−1), and good cycling (628 mA h g−1 after 100 cycles) and rate performance (a reversible capacity of 372 mA h g−1 at the rate of 5 A g−1). - Abstract: CoMoO4 nanorods with small diameter (about 40∼60 nm in width and 1.5∼2 μm in length) uniformly distributed on reduced graphene oxide (rGO) nanosheets were synthesized via a facile, green wet chemical method. The as-prepared CoMoO4/rGO composite was studied as anode material for lithium-ion batteries. It delivered an initial discharge capacity of 1496 mA h g−1 at a current density of 100 mA g−1, and good cycling (628 mA h g−1 after 100 cycles) and rate performance (a reversible capacity of 372 mA h g−1 at the rate of 5 A g−1). The excellent electrochemical performance can be attributed to the small diameter of the synthesized CoMoO4 nanorods and the presence of rGO nanosheets, making it a promising candidate for next generation anode material of rechargeable lithium ion batteries

  11. Hard carbon nanoparticles as high-capacity, high-stability anodic materials for Na-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Lifen; Cao, Yuliang; Henderson, Wesley A.; Sushko, Maria L.; Shao, Yuyan; Xiao, Jie; Wang, Wei; Engelhard, Mark H.; Nie, Zimin; Liu, Jun

    2016-01-01

    Hard carbon nanoparticles (HCNP) were synthesized by the pyrolysis of a polyaniline precursor. The measured Na+ cation diffusion coefficient (10-13-10-15cm2s-1) in the HCNP obtained at 1150 °C is two orders of magnitude lower than that of Li+ in graphite (10-10-13-15cm2s-1), indicating that reducing the carbon particle size is very important for improving electrochemical performance. These measurements also enable a clear visualization of the stepwise reaction phases and rate changes which occur throughout the insertion/extraction processes in HCNP, The electrochemical measurements also show that the nano-sized HCNP obtained at 1150 °C exhibited higher practical capacity at voltages lower than 1.2 V (vs. Na/Na⁺), as well as a prolonged cycling stability, which is attributed to an optimum spacing of 0.366 nm between the graphitic layers and the nano particular size resulting in a low-barrier Na+ cation insertion. These results suggest that HCNP is a very promising high-capacity/stability anode for low cost sodium-ion batteries (SIBs).

  12. Preparation of C/Ni-NiO composite nanofibers for anode materials in lithium-ion batteries

    Science.gov (United States)

    Luo, Chenghao; Lu, Weili; Li, Yu; Feng, Yiyu; Feng, Wei; Zhao, Yunhui; Yuan, Xiaoyan

    2013-11-01

    Carbon nanofibers (CNFs) embedded with various amounts of Ni and NiO nanoparticles (C/Ni-NiO) were prepared by electrospinning of polyacrylonitrile (PAN), followed by heat treatment. The structure and composition of the obtained C/Ni-NiO composite nanofibers were analyzed by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The results suggested that the morphology, nanofiber diameter, and the content of the Ni-NiO nanoparticles in the CNFs were controlled by different amounts of nickel acetate added into the PAN. The electrochemical measurements of a charge/discharge experiment and a cyclic voltammetry test indicated that the content and the size of Ni-NiO nanoparticles embedded in the CNFs had a great influence on the electrochemical performance of lithium-ion batteries. CNFs embedded with a certain content of Ni-NiO nanoparticles as binder-free anodes for rechargeable lithium-ion batteries exhibited improved electrochemical performance, including high reversible capacities, good capacity retention, and stable cycling performance. This is mainly ascribed to the formation of a well-distributed Ni-NiO nanoparticle structure and the buffering role of the carbon nanofiber matrix, together with the high theoretical capacity of NiO and the increase in electrode connectivity caused by the formation of electrochemically inactive Ni nanoparticles.

  13. Synthesis of Mesoporous ZnO Nanosheets via Facile Solvothermal Method as the Anode Materials for Lithium-ion Batteries.

    Science.gov (United States)

    Wang, Xin; Huang, Lanyan; Zhao, Yan; Zhang, Yongguang; Zhou, Guofu

    2016-12-01

    Mesoporous ZnO nanosheets are synthesized through a room temperature solvothermal method. Transmission and scanning electronic microscopy observations indicate that as-prepared ZnO hierarchical aggregates are composed and assembled by nanosheets with a length of 1-2 μm and a thickness of 10-20 nm, and interlaced ZnO nanosheets irregularly stack together, forming a three-dimensional network. Furthermore, large mesopores are embedded in the walls of ZnO nanosheets, confirmed by Brunauer-Emmett-Teller (BET) measurement. Accordingly, the resulting ZnO anode exhibits a high and stable specific discharge capacity of 421 mAh g(-1) after 100 cycles at 200 mA g(-1) and a good rate capability. Such electrochemical performance could be attributed to the multiple synergistic effects of its mesoporous nanosheet structure, which can not only provide a large specific surface area for lithium storage, but also favor the ion transport and electrolyte diffusion. PMID:26815606

  14. Raw data for neutron scattering experiments described in PhD thesis "NMR and neutron total scattering studies of silicon-based anode materials for lithium-ion batteries"

    OpenAIRE

    Kerr, Christopher J

    2014-01-01

    The research focuses on the structural transformations in silicon and lithium silicides during the electrochemical reactions that occur when using silicon as an anode material for lithium-ion batteries. This dataset contains raw neutron-scattering data, as well as battery charger log files showing the electrical performance of the batteries. Results of the data processing will be uploaded to a separate dataset.

  15. Characteristics and Electrochemical Performance of Si-Carbon Nanofibers Composite as Anode Material for Binder-Free Lithium Secondary Batteries.

    Science.gov (United States)

    Hyun, Yura; Park, Heai-Ku; Park, Ho-Seon; Lee, Chang-Seop

    2015-11-01

    The carbon nanofibers (CNFs) and Si-CNFs composite were synthesized using a chemical vapor deposition (CVD) method with an iron-copper catalyst and silicon-covered Ni foam. Acetylene as a carbon source was flowed into the quartz reactor of a tubular furnace heated to 600 degrees C. This temperature was maintained for 10 min to synthesize the CNFs. The morphologies, compositions, and crystal quality of the prepared CNFs were characterized by Scanning electron microscopy (SEM), Energy dispersive spectroscopy (EDS), X-ray Diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The electrochemical characteristics of the Si-CNFs composite as an anode of the Li secondary batteries were investigated using a three-electrode cell. The as-deposited Si-CNF composite on the Ni foam was directly employed as an working electrode without any binder, and lithium foil was used as the counter and reference electrode. A glass fiber separator was used as the separator membrane. Two kinds of electrolytes were employed; 1) 1 M LiPF6 was dissolved in a mixture of EC (ethylene carbonate): PC (propylene carbonate): EMC (Ethyl methyl carbonate) in a 1:1:1 volume ratio and 2) 1 M LiClO4 was dissolved in a mixture of propylene carbonate (PC): ethylene carbonate (EC) in a 1:1 volume ratio. The galvanostatic charge-discharge cycling and cyclic voltammetry measurements were carried out at room temperature by using a battery tester. The resulting Si-CNFs composite achieved the large discharge capacity of 613 mAh/g and much improved cycle-ability with the retention rate of 87% after 20 cycles. PMID:26726625

  16. Alkali-Metal-Ion-Functionalized Graphene Oxide as a Superior Anode Material for Sodium-Ion Batteries.

    Science.gov (United States)

    Wan, Fang; Li, Yu-Han; Liu, Dai-Huo; Guo, Jin-Zhi; Sun, Hai-Zhu; Zhang, Jing-Ping; Wu, Xing-Long

    2016-06-01

    Although graphene oxide (GO) has large interlayer spacing, it is still inappropriate to use it as an anode for sodium-ion batteries (SIBs) because of the existence of H-bonding between the layers and ultralow electrical conductivity which impedes the Na(+) and e(-) transformation. To solve these issues, chemical, thermal, and electrochemical procedures are traditionally employed to reduce GO nanosheets. However, these strategies are still unscalable, consume high amounts of energy, and are expensive for practical application. Here, for the first time, we describe the superior Na storage of unreduced GO by a simple and scalable alkali-metal-ion (Li(+) , Na(+) , K(+) )-functionalized process. The various alkali metals ions, connecting with the oxygen on GO, have played different effects on morphology, porosity, degree of disorder, and electrical conductivity, which are crucial for Na-storage capabilities. Electrochemical tests demonstrated that sodium-ion-functionalized GO (GNa) has shown outstanding Na-storage performance in terms of excellent rate capability and long-term cycle life (110 mAh g(-1) after 600 cycles at 1 A g(-1) ) owing to its high BET area, appropriate mesopore, high degree of disorder, and improved electrical conductivity. Theoretical calculations were performed using the generalized gradient approximation (GGA) to further study the Na-storage capabilities of functionalized GO. These calculations have indicated that the Na-O bond has the lowest binding energy, which is beneficial to insertion/extraction of the sodium ion, hence the GNa has shown the best Na-storage properties among all comparatives functionalized by other alkali metal ions. PMID:27136376

  17. Chemo-mechanical softening during in situ nanoindentation of anodic porous alumina with anodization processing

    OpenAIRE

    Cheng, C; Ngan, AHW

    2013-01-01

    Simultaneous application of mechanical stresses on a material as it undergoes an electrochemical reaction can result in interesting coupling effects between the chemical and mechanical responses of the material. In this work, anodic porous alumina supported on Al is found to exhibit significant softening during in situ nanoindentation with anodization processing. Compared with ex situ nanoindentation without anodization processing, the in situ hardness measured on the alumina is found to be m...

  18. Unique Urchin-like Ca2Ge7O16 Hierarchical Hollow Microspheres as Anode Material for the Lithium Ion Battery.

    Science.gov (United States)

    Li, Dan; Feng, Chuanqi; Liu, Hua Kun; Guo, Zaiping

    2015-01-01

    Germanium is an outstanding anode material in terms of electrochemical performance, especially rate capability, but its developments are hindered by its high price because it is rare in the crust of earth, and its huge volume variation during the lithium insertion and extraction. Introducing other cheaper elements into the germanium-based material is an efficient way to dilute the high price, but normally sacrifice its electrochemical performance. By the combination of nanostructure design and cheap element (calcium) introduction, urchin-like Ca2Ge7O16 hierarchical hollow microspheres have been successfully developed in order to reduce the price and maintain the good electrochemical properties of germanium-based material. The electrochemical test results in different electrolytes show that ethylene carbonate/dimethyl carbonate/diethyl carbonate (3/4/3 by volume) with 5 wt% fluoroethylene carbonate additive is the most suitable solvent for the electrolyte. From the electrochemical evaluation, the as-synthesized Ca2Ge7O16 hollow microspheres exhibit high reversible specific capacity of up to 804.6 mA h g(-1) at a current density of 100 mA g(-1) after 100 cycles and remarkable rate capability of 341.3 mA h g(-1) at a current density of 4 A g(-1). The growth mechanism is proposed based on our experimental results on the growth process. PMID:26061390

  19. Morphology-controlled synthesis and electrochemical performance of NiCo{sub 2}O{sub 4} as anode material in lithium-ion battery application

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Shan; Lu, Lin; Zhang, Qing; Zheng, Hao; Liu, Lian; Yin, Shengyu; Wang, Shiquan, E-mail: wsqhao@126.com; Li, Guohua; Feng, Chuanqi [Hubei University, Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for Synthesis and Applications of Organic Functional Molecules (China)

    2015-09-15

    Mixed-valence oxide precursors were synthesized by a solvothermal method using NiSO{sub 4}, CoSO{sub 4}, and NH{sub 4}HCO{sub 3} as raw materials. The precursors were heat-treated in a muffle furnace at 500 °C to obtain the products (NiCo{sub 2}O{sub 4}). The samples were characterized by X-ray diffractometer, thermogravimetric, energy-dispersive spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results show that dumbbells, microspheres, and particle-like NiCo{sub 2}O{sub 4} were successfully synthesized by changing the volume of solvent and solvothermal temperature. The NiCo{sub 2}O{sub 4} microspheres (prepared at 180 °C with 30 ml solvent) as anode material for lithium-ion battery, exhibit a reversible discharge capacity of 1160 mAh g{sup −1} and good cycling stability (729 mAh g{sup −1} after 50 cycles) at a constant current of 100 mA g{sup −1} in the voltage range of 0.01–3.0 V due to its high crystallinity and uniform porous morphology. Hence, the synthetic method could be extended to other high-capacity ternary metal oxide materials for lithium-ion battery application.

  20. Morphology-controlled synthesis and electrochemical performance of NiCo2O4 as anode material in lithium-ion battery application

    International Nuclear Information System (INIS)

    Mixed-valence oxide precursors were synthesized by a solvothermal method using NiSO4, CoSO4, and NH4HCO3 as raw materials. The precursors were heat-treated in a muffle furnace at 500 °C to obtain the products (NiCo2O4). The samples were characterized by X-ray diffractometer, thermogravimetric, energy-dispersive spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results show that dumbbells, microspheres, and particle-like NiCo2O4 were successfully synthesized by changing the volume of solvent and solvothermal temperature. The NiCo2O4 microspheres (prepared at 180 °C with 30 ml solvent) as anode material for lithium-ion battery, exhibit a reversible discharge capacity of 1160 mAh g−1 and good cycling stability (729 mAh g−1 after 50 cycles) at a constant current of 100 mA g−1 in the voltage range of 0.01–3.0 V due to its high crystallinity and uniform porous morphology. Hence, the synthetic method could be extended to other high-capacity ternary metal oxide materials for lithium-ion battery application

  1. Hollow NiO nanotubes synthesized by bio-templates as the high performance anode materials of lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: •Hollow NiO nanotubular materials are synthesized using bio-template method. •The prepared nanotube is composed of nanosized NiO with sizes smaller than 20 nm. •It exhibits a stable reversible capacity of 620 mA h g−1 and good rate performance. -- Abstract: Hollow NiO nanotubular material is prepared by a facile bio-template engaged route using filter paper as the template for Li-ion batteries and optimizing the reaction conditions. The as-obtained products keep the structure of filter paper, resulting in the formation of hollow NiO nanotube aggregates with strong framework and loose hollow mesoporous structure. As anode material for lithium ion batteries, it exhibits a stable reversible capacity of 620 mA h g−1 and keeps over 600 mA h g−1 after 100 cycles except for the first cycle at current density of 200 mA g−1. The NiO eletrode also exhibits good rate capability. The nanostructured characteristics of NiO particles embedded in the nanotube ensure the high capacity in the electrode. The unique hollow structures can shorten the length of Li-ion diffusion and offer a sufficient void space, which sufficiently alleviates the mechanical stress caused by volume change. Herein, the hollow NiO nanotubular electrode exhibits excellent electrochemical performance

  2. Unique Urchin-like Ca2Ge7O16 Hierarchical Hollow Microspheres as Anode Material for the Lithium Ion Battery

    Science.gov (United States)

    Li, Dan; Feng, Chuanqi; Liu, Hua Kun; Guo, Zaiping

    2015-06-01

    Germanium is an outstanding anode material in terms of electrochemical performance, especially rate capability, but its developments are hindered by its high price because it is rare in the crust of earth, and its huge volume variation during the lithium insertion and extraction. Introducing other cheaper elements into the germanium-based material is an efficient way to dilute the high price, but normally sacrifice its electrochemical performance. By the combination of nanostructure design and cheap element (calcium) introduction, urchin-like Ca2Ge7O16 hierarchical hollow microspheres have been successfully developed in order to reduce the price and maintain the good electrochemical properties of germanium-based material. The electrochemical test results in different electrolytes show that ethylene carbonate/dimethyl carbonate/diethyl carbonate (3/4/3 by volume) with 5 wt% fluoroethylene carbonate additive is the most suitable solvent for the electrolyte. From the electrochemical evaluation, the as-synthesized Ca2Ge7O16 hollow microspheres exhibit high reversible specific capacity of up to 804.6 mA h g-1 at a current density of 100 mA g-1 after 100 cycles and remarkable rate capability of 341.3 mA h g-1 at a current density of 4 A g-1. The growth mechanism is proposed based on our experimental results on the growth process.

  3. Synthesis of TiO2 by electrochemical method from TiCl4 solution as anode material for lithium-ion batteries

    Science.gov (United States)

    Nur, Adrian; Purwanto, Agus; Jumari, Arif; Dyartanti, Endah R.; Sari, Sifa Dian Permata; Hanifah, Ita Nur

    2016-02-01

    Metal oxide combined with graphite becomes interesting composition. TiO2 is a good candidate for Li ion battery anode because of cost, availability of sufficient materials, and environmentally friendly. TiO2 gravimetric capacity varied within a fairly wide range. TiO2 crystals form highly depends on the synthesis method used. The electrochemical method is beginning to emerge as a valuable option for preparing TiO2 powders. Using the electrochemical method, the particle can easily be controlled by simply adjusting the imposed current or potential to the system. In this work, the effects of some key parameters of the electrosynthesis on the formation of TiO2 have been investigated. The combination of graphite and TiO2 particle has also been studied for lithium-ion batteries. The homogeneous solution for the electrosynthesis of TiO2 powders was TiCl4 in ethanol solution. The electrolysis was carried out in an electrochemical cell consisting of two carbon electrodes with dimensions of (5 × 2) cm. The electrodes were set parallel with a distance of 2.6 cm between the electrodes and immersed in the electrolytic solution at a depth of 2 cm. The electrodes were connected to the positive and negative terminals of a DC power supply. The electrosynthesis was performed galvanostatically at 0.5 to 2.5 hours and voltages were varied from 8 to 12 V under constant stirring at room temperature. The resulted suspension was aged at 48 hrs, filtered, dried directly in an oven at 150°C for 2 hrs, washed 2 times, and dried again 60 °C for 6 hrs. The particle product has been used to lithium-ion battery as anode. Synthesis of TiO2 particle by electrochemical method at 10 V for 1 to 2.5 hrs resulted anatase and rutile phase.

  4. Nitrogen-treated Hierarchical Macro-/Mesoporous TiO2 Used as Anode Materials for Lithium Ion Batteries with High Performance at Elevated Temperatures

    International Nuclear Information System (INIS)

    Abstract: In this article, we employed nitrogen gas treatment as an effective strategy in caclination to significantly improve the performance of hierarchical macro-/mesoprous TiO2 as anode materials for lithium ion batteries at an elevated temperature of 55 °C. Room-temperature synthesized macro-/mesoprous TiO2 was calcined under nitrogen and air conditions at 300 °C for 3 h, respectively. The specific surface area was studied by nitrogen adsorption/desorption measurement and the surface chemistry was studied by X-ray photoelectron spectroscopy (XPS). It was found that the macro-/mesoprous TiO2 had a specific surface area of 330 m2 g−1 after calcination under nitrogen atmosphere, while only 248 m2 g−1 after calcination under air atmosphere. Electrochemical tests showed that, in comparison to air-treated TiO2, nitrogen-treated TiO2 exhibited considerable high capacity and good rate performance as a lithium ion battery anode at the elevated temperature (55 °C). It had a capacity of 293 mAh g−1 after 50 cycles at mixed current densities of 30, 150, and 500 mA g−1, while the air-treated TiO2 only had a capacity of 187 mAh g−1 after 50 cycles. This improvement of lithium ion storage capability can be ascribed to the nitrogen-treatment effect on crystallinity and the presence of surface defects on TiO2 nanostructure

  5. Development of mats composed by TiO{sub 2} and carbon dual electrospun nanofibers: A possible anode material in microbial fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Gomez, Nora A.; Balderas-Renteria, Isaias [Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Av. Universidad S/N Cd. Universitaria San Nicolás de los Garza Nuevo León, C.P. 66451 México (Mexico); Garcia-Gutierrez, Domingo I. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Av. Universidad S/N Cd. Universitaria San Nicolás de los Garza Nuevo León, C.P. 66451 México (Mexico); Universidad Autónoma de Nuevo León, Centro de Innovación, Investigación y Desarrollo en Ingeniería y Tecnología, PIIT, Av. Universidad S/N Cd. Universitaria San Nicolás de los Garza Nuevo León, C.P. 66451 México (Mexico); Mosqueda, Hugo A. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Av. Universidad S/N Cd. Universitaria San Nicolás de los Garza Nuevo León, C.P. 66451 México (Mexico); and others

    2015-03-15

    Highlights: • Dual nanofiber of TiO{sub 2}–C/C showed excellent electrical performance. • TiO{sub 2}–C/C dual nanofiber can host a dense biofilm of electroactivated Escherichia coli. • Dual nanofibers can be applied as anode to obtain electricity in microbial fuel cells. - Abstract: A new material based on TiO{sub 2(rutile)}–C{sub (semi-graphitic)}/C{sub (semi-graphitic)} dual nanofiber mats is presented, whose composition and synthesis methodology are fundamental factors for the development of exoelectrogenic biofilms on its surface. Therefore, this material shows the required characteristics for possible applications in the bioconversion process of an organic substrate to electricity in a microbial fuel cell. Chronoamperometry, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and electrical conductivity analyses showed excellent electrical performance of the material for the application intended; a resistance as low as 3.149 Ω was able to be measured on this material. Furthermore, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies confirmed the morphology sought on the material for the application intended, dual nanofibres TiO{sub 2(rutile)}–C{sub (semi-graphitic)}/C{sub (semi-graphitic)} with a side by side configuration. The difference in composition of the fibers forming the dual nanofibers was clearly observed and confirmed by energy dispersive X-ray spectroscopy (EDXS), and their crystal structure was evident in the results obtained from selected area electron diffraction (SAED) studies. This nanostructured material presented a high surface area and is biocompatible, given that it can host a dense biofilm of electroactivated Escherichia coli. In this study, the maximum current density obtained in a half microbial fuel cell was 8 A/m{sup 2} (0.8 mA/cm{sup 2})

  6. Development of mats composed by TiO2 and carbon dual electrospun nanofibers: A possible anode material in microbial fuel cells

    International Nuclear Information System (INIS)

    Highlights: • Dual nanofiber of TiO2–C/C showed excellent electrical performance. • TiO2–C/C dual nanofiber can host a dense biofilm of electroactivated Escherichia coli. • Dual nanofibers can be applied as anode to obtain electricity in microbial fuel cells. - Abstract: A new material based on TiO2(rutile)–C(semi-graphitic)/C(semi-graphitic) dual nanofiber mats is presented, whose composition and synthesis methodology are fundamental factors for the development of exoelectrogenic biofilms on its surface. Therefore, this material shows the required characteristics for possible applications in the bioconversion process of an organic substrate to electricity in a microbial fuel cell. Chronoamperometry, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and electrical conductivity analyses showed excellent electrical performance of the material for the application intended; a resistance as low as 3.149 Ω was able to be measured on this material. Furthermore, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies confirmed the morphology sought on the material for the application intended, dual nanofibres TiO2(rutile)–C(semi-graphitic)/C(semi-graphitic) with a side by side configuration. The difference in composition of the fibers forming the dual nanofibers was clearly observed and confirmed by energy dispersive X-ray spectroscopy (EDXS), and their crystal structure was evident in the results obtained from selected area electron diffraction (SAED) studies. This nanostructured material presented a high surface area and is biocompatible, given that it can host a dense biofilm of electroactivated Escherichia coli. In this study, the maximum current density obtained in a half microbial fuel cell was 8 A/m2 (0.8 mA/cm2)

  7. Electrically Conductive Anodized Aluminum Surfaces

    Science.gov (United States)

    Nguyen, Trung Hung

    2006-01-01

    Anodized aluminum components can be treated to make them sufficiently electrically conductive to suppress discharges of static electricity. The treatment was conceived as a means of preventing static electric discharges on exterior satin-anodized aluminum (SAA) surfaces of spacecraft without adversely affecting the thermal-control/optical properties of the SAA and without need to apply electrically conductive paints, which eventually peel off in the harsh environment of outer space. The treatment can also be used to impart electrical conductivity to anodized housings of computers, medical electronic instruments, telephoneexchange equipment, and other terrestrial electronic equipment vulnerable to electrostatic discharge. The electrical resistivity of a typical anodized aluminum surface layer lies between 10(exp 11) and 10(exp 13) Omega-cm. To suppress electrostatic discharge, it is necessary to reduce the electrical resistivity significantly - preferably to anodized surface becomes covered and the pores in the surface filled with a transparent, electrically conductive metal oxide nanocomposite. Filling the pores with the nanocomposite reduces the transverse electrical resistivity and, in the original intended outer-space application, the exterior covering portion of the nanocomposite would afford the requisite electrical contact with the outer-space plasma. The electrical resistivity of the nanocomposite can be tailored to a value between 10(exp 7) and 10(exp 12) Omega-cm. Unlike electrically conductive paint, the nanocomposite becomes an integral part of the anodized aluminum substrate, without need for adhesive bonding material and without risk of subsequent peeling. The electrodeposition process is compatible with commercial anodizing production lines. At present, the electronics industry uses expensive, exotic, electrostaticdischarge- suppressing finishes: examples include silver impregnated anodized, black electroless nickel, black chrome, and black copper. In

  8. Reactions on carbon anodes in aluminium electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Eidet, Trygve

    1997-12-31

    The consumption of carbon anodes and energy in aluminium electrolysis is higher than what is required theoretically. This thesis studies the most important of the reactions that consume anode materials. These reactions are the electrochemical anode reaction and the airburn and carboxy reactions. The first part of the thesis deals with the kinetics and mechanism of the electrochemical anode reaction using electrochemical impedance spectroscopy. The second part deals with air and carboxy reactivity of carbon anodes and studies the effects of inorganic impurities on the reactivity of carbon anodes in the aluminium industry. Special attention is given to sulphur since its effect on the carbon gasification is not well understood. Sulphur is always present in anodes, and it is expected that the sulphur content of available anode cokes will increase in the future. It has also been suggested that sulphur poisons catalyzing impurities in the anodes. Other impurities that were investigated are iron, nickel and vanadium, which are common impurities in anodes which have been reported to catalyze carbon gasification. 88 refs., 92 figs., 24 tabs.

  9. 3D Hollow Sn@Carbon-Graphene Hybrid Material as Promising Anode for Lithium-Ion Batteries

    OpenAIRE

    Xiaoyu Zheng; Wei Lv; Yan-Bing He; Chen Zhang; Wei Wei; Ying Tao; Baohua Li; Quan-Hong Yang

    2014-01-01

    A 3D hollow Sn@C-graphene hybrid material (HSCG) with high capacity and excellent cyclic and rate performance is fabricated by a one-pot assembly method. Due to the fast electron and ion transfer as well as the efficient carbon buffer structure, the hybrid material is promising in high-performance lithium-ion battery.

  10. An investigation into the doping and crystallinity of anodically fabricated titania nanotube arrays: Towards an efficient material for solar energy applications

    Science.gov (United States)

    Allam Abdel-Motalib, Nageh Khalaf

    The primary focus of this dissertation was to improve the properties of the anodically fabricated TiO2 nanotube arrays; notably its band gap and crystallinity while retaining its tubular structure unaffected. The underlying hypothesis was that controlling the crystallinity and band gap while retaining the tubular structure will result in an enormous enhancement of the photoconversion capability of the material. To this end, a direct one-step facile approach for the in-situ doping of TiO2 nanotube arrays during their electrochemical fabrication in both aqueous and non-aqueous electrolytes has been investigated. The effect of doping on the morphology, optical and photoelectrochemical properties of the fabricated nanotube arrays is discussed. In an effort to improve the crystallinity of the anodically fabricated TiO2 nanotube arrays while retaining the tubular morphology, novel processing routes have been investigated to fabricate crystalline TiO 2 nanotube array electrodes. For the sake of comparison, the nanotubes were annealed at high temperature using the conventionally used procedure. The samples were found to be stable up to temperatures around 580°C, however, higher temperatures resulted in crystallization of the titanium support which disturbed the nanotube architecture, causing it to partially and gradually collapse and densify. The maximum photoconversion efficiency for water splitting using 7 mum-TiO2 nanotube arrays electrodes annealed at 580°C was measured to be about 10% under UV illumination. We investigated the effect of subsequent low temperature crystallization step. Rapid infrared (IR) annealing was found to be an efficient technique for crystallizing the nanotube array films within a few minutes. The IR-annealed 7mum-nanotube array films showed significant photoconversion efficiencies (eta=13.13%) upon their use as photoanodes to photoelectrochemically split water under UV illumination. This was related, in part, to the reduction in the barrier

  11. Columbia/Willamette Skill Builders Consortium. Final Performance Report. Appendix 5B Anodizing Inc. (Aluminum Extrusion Manufacturing). Basic Measurement Math. Instructors' Reports and Sample Curriculum Materials.

    Science.gov (United States)

    Taylor, Marjorie; And Others

    Anodizing, Inc., Teamsters Local 162, and Mt. Hood Community College (Oregon) developed a workplace literacy program for workers at Anodizing. These workers did not have the basic skill competencies to benefit from company training efforts in statistical process control and quality assurance and were not able to advance to lead and supervisory…

  12. Electrochemical properties of CoFe3Sb12 as potential anode material for lithium-ion batteries

    Institute of Scientific and Technical Information of China (English)

    赵新兵; 钟耀东; 曹高劭

    2004-01-01

    A skutterudite-related antimonide, CoFe3Sb12,was prepared with vacuum melting.XRD analysis showed the material contained Sb, FeSb2, CoSb2 and CoSb3 phases.The electrochemical properties of the ball-milled CoFe3Sb12-10wt% graphite composite were studied using pure lithium as the reference electrode. A maximal lithium inserting capacity of about 860 mAh/g was obtained in the first cycle.The reversible capacity of the material was about 560mAh/g in the first cycle and decreased to ca.320 mAh/g and 250 mAh/g after 10 and 20 cycles respectively.Ex-situ XRD analyses showed that the antimonides in the pristine material were decomposed after the first discharge and that antimony was the active element for lithium to insert into the host material.

  13. A facile solution combustion synthesis of nanosized amorphous iron oxide incorporated in a carbon matrix for use as a high-performance lithium ion battery anode material

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Chunyu, E-mail: chunyu6zhu@gmail.com; Saito, Genki; Akiyama, Tomohiro

    2015-06-05

    Highlights: • Iron oxide–carbon composite was fabricated by facile solution combustion synthesis. • Iron oxide nanoparticles of about 5 nm were uniformly embedded in dense carbon matrix. • The composite exhibited enhanced cyclability and rate capability. • A high capacity of 687 mA h g{sup −1} after 200 cycles at a current rate of 0.5 A g{sup −1} were obtained. - Abstract: An amorphous iron oxide–carbon composite has been fabricated through an effective, inexpensive, and scalable method employing solution combustion synthesis. Amorphous iron oxide nanoparticles with diameters of about 5 nm were synthesized and uniformly embedded in a dense carbon matrix. The synthesized composite exhibits enhanced cyclability and rate capability, showing a high reversible capacity of 687 mA h g{sup −1} after 200 discharge/charge cycles at a current rate of 0.5 A g{sup −1}, compared to the 400 mA h g{sup −1} observed for Fe{sub 2}O{sub 3} nanoparticles. This enhanced performance was retained despite more demanding conditions, delivering a high capacity of about 525 mA h g{sup −1} and a nearly perfect coulombic efficiency even after 400 cycles at 1 A g{sup −1}. The easy production and superior electrochemical properties of this composite suggest that it is a promising material for use as an anode material in high performance lithium ion batteries.

  14. Development of anode material based on La-substituted SrTiO{sub 3} perovskites doped with manganese and/or gallium for SOFC

    Energy Technology Data Exchange (ETDEWEB)

    Escudero, M.J. [Dpto Energia, CIEMAT, Av. Complutense 22, 28040 Madrid (Spain); School of Chemistry, Purdie Building, University of St Andrews, St Andres, Fife KY16 9ST (United Kingdom); Irvine, J.T.S. [School of Chemistry, Purdie Building, University of St Andrews, St Andres, Fife KY16 9ST (United Kingdom); Daza, L. [Dpto Energia, CIEMAT, Av. Complutense 22, 28040 Madrid (Spain); Instituto de Catalisis y Petroleoquimica (CSIC), Campus Cantoblanco, C/Marie Curie 2, 28049 Madrid (Spain)

    2009-07-01

    Materials based on La-substituted SrTiO{sub 3} perovskites doped with manganese and/or gallium for SOFC have been studied as novel anodes for solid oxide fuel cell. La{sub 4}Sr{sub 8}Ti{sub 11}Mn{sub 1-x}Ga{sub x}O{sub 38-{delta}} (0 {<=} x {<=} 1) oxides were synthesized by solid state reaction and the influences of the manganese and/or gallium content on the structure, morphology, thermal properties and electrical conductivity of these materials has been investigated. All compounds show cubic structure with a space group Pm-3m. These compounds presented high electrical conductivity values under reducing atmosphere between 7.9 and 6.8 S cm{sup -1} at 900 C. For the composition x {>=} 0.5, the thermal expansion coefficient in both reducing and oxidizing atmosphere are close to that of SOFC electrolytes (8YSZ, CGD). In general, the substitution of Ga by Mn causes a slight reduction in each of the following, lattice parameter, degree of oxygen loss on reduction, thermal expansion coefficient, and electrical conductivity. (author)

  15. Development of anode material based on La-substituted SrTiO 3 perovskites doped with manganese and/or gallium for SOFC

    Science.gov (United States)

    Escudero, M. J.; Irvine, J. T. S.; Daza, L.

    Materials based on La-substituted SrTiO 3 perovskites doped with manganese and/or gallium for SOFC have been studied as novel anodes for solid oxide fuel cell. La 4Sr 8Ti 11Mn 1- xGa xO 38- δ (0 ≤ x ≤ 1) oxides were synthesized by solid state reaction and the influences of the manganese and/or gallium content on the structure, morphology, thermal properties and electrical conductivity of these materials has been investigated. All compounds show cubic structure with a space group Pm-3m. These compounds presented high electrical conductivity values under reducing atmosphere between 7.9 and 6.8 S cm -1 at 900 °C. For the composition x ≥ 0.5, the thermal expansion coefficient in both reducing and oxidizing atmosphere are close to that of SOFC electrolytes (8YSZ, CGD). In general, the substitution of Ga by Mn causes a slight reduction in each of the following, lattice parameter, degree of oxygen loss on reduction, thermal expansion coefficient, and electrical conductivity.

  16. Silicon on conductive self-organized TiO2 nanotubes - A high capacity anode material for Li-ion batteries

    Science.gov (United States)

    Brumbarov, Jassen; Kunze-Liebhäuser, Julia

    2014-07-01

    The study of high energy density electrode materials is central to the development of Li+-ion batteries. Si is among the most promising anode materials for next generation Li+-ion batteries. Model composite electrodes of self-organized, conductive titania (TiO2-x-C) nanotubes coated with silicon (Si) via plasma enhanced chemical vapor deposition (PECVD) are produced and studied in terms of their lithiation/delithiation characteristics. The nanotube array provides direct one dimensional electron transport to the current collector, without the need of adding binders or conductive additives. Both components of the composite can be lithiated delivering 120 μAh cm-2 total capacity for a film thickness of 1 μm and a Si loading of ∼10 wt.%. 86% capacity retention upon 88 cycles at a rate of C/5 and 60 μAh cm-2 total capacity at a rate of 10 C are achieved owing to the low lateral expansion and thus good adhesion of the thin Si coating to the TiO2-x-C nanotubes, and due to the formation of a stable solid electrolyte interface (SEI) in ethylene-carbonate (EC), dimethyl-carbonate (DMC), vinylene-carbonate (VC) electrolyte with 1 M LiPF6.

  17. First Introduction of NiSe2 to Anode Material for Sodium-Ion Batteries: A Hybrid of Graphene-Wrapped NiSe2/C Porous Nanofiber

    Science.gov (United States)

    Cho, Jung Sang; Lee, Seung Yeon; Kang, Yun Chan

    2016-03-01

    The first-ever study of nickel selenide materials as efficient anode materials for Na-ion rechargeable batteries is conducted using the electrospinning process. NiSe2-reduced graphene oxide (rGO)-C composite nanofibers are successfully prepared via electrospinning and a subsequent selenization process. The electrospun nanofibers giving rise to these porous-structured composite nanofibers with optimum amount of amorphous C are obtained from the polystyrene to polyacrylonitrile ratio of 1/4. These composite nanofibers also consist of uniformly distributed single-crystalline NiSe2 nanocrystals that have a mean size of 27 nm. In contrast, the densely structured bare NiSe2 nanofibers formed via selenization of the pure NiO nanofibers consist of large crystallites. The initial discharge capacities of the NiSe2-rGO-C composite and bare NiSe2 nanofibers at a current density of 200 mA g‑1 are 717 and 755 mA h g‑1, respectively. However, the respective 100th-cycle discharge capacities of the former and latter are 468 and 35 mA h g‑1. Electrochemical impedance spectroscopy measurements reveal the structural stability of the composite nanofibers during repeated Na-ion insertion and extraction processes. The excellent Na-ion storage properties of these nanofibers are attributed to this structural stability.

  18. Facile hybridization of Ni@Fe2O3 superparticles with functionalized reduced graphene oxide and its application as anode material in lithium-ion batteries.

    Science.gov (United States)

    Backert, Gregor; Oschmann, Bernd; Tahir, Muhammad Nawaz; Mueller, Franziska; Lieberwirth, Ingo; Balke, Benjamin; Tremel, Wolfgang; Passerini, Stefano; Zentel, Rudolf

    2016-09-15

    In our present work we developed a novel graphene wrapping approach of Ni@Fe2O3 superparticles, which can be extended as a concept approach for other nanomaterials as well. It uses sulfonated reduced graphene oxide, but avoids thermal treatments and use of toxic agents like hydrazine for its reduction. The modification of graphene oxide is achieved by the introduction of sulfate groups accompanied with reduction and elimination reactions, due to the treatment with oleum. The successful wrapping of nanoparticles is proven by energy dispersive X-ray spectroscopy, high-resolution transmission electron microscopy and Raman spectroscopy. The developed composite material shows strongly improved performance as anode material in lithium-ion batteries (compared to unwrapped Ni@Fe2O3) as it offers a reversible capacity of 1051mAhg(-1) after 40 cycles at C/20, compared with 460mAhg(-1) for unwrapped Ni@Fe2O3. The C rate capability is also improved by the wrapping approach, as specific capacities for wrapped particles are about twice of those offered by unwrapped particles. Additionally, the benefit for the use of the advanced superparticle morphology is demonstrated by comparing wrapped Ni@Fe2O3 particles with wrapped Fe2O3 nanorice. PMID:27295319

  19. h-BN Nanosheets as 2D Substrates to Load 0D Fe3 O4 Nanoparticles: A Hybrid Anode Material for Lithium-Ion Batteries.

    Science.gov (United States)

    Duan, Zhi-Qiang; Liu, Yi-Tao; Xie, Xu-Ming; Ye, Xiong-Ying; Zhu, Xiao-Dong

    2016-03-18

    h-BN, as an isoelectronic analogue of graphene, has improved thermal mechanical properties. Moreover, the liquid-phase production of h-BN is greener since harmful oxidants/reductants are unnecessary. Here we report a novel hybrid architecture by employing h-BN nanosheets as 2D substrates to load 0D Fe3 O4 nanoparticles, followed by phenol/formol carbonization to form a carbon coating. The resulting carbon-encapsulated h-BN@Fe3 O4 hybrid architecture exhibits synergistic interactions: 1) The h-BN nanosheets act as flexible 2D substrates to accommodate the volume change of the Fe3 O4 nanoparticles; 2) The Fe3 O4 nanoparticles serve as active materials to contribute to a high specific capacity; and 3) The carbon coating not only protects the hybrid architecture from deformation but also keeps the whole electrode highly conductive. The synergistic interactions translate into significantly enhanced electrochemical performances, laying a basis for the development of superior hybrid anode materials. PMID:26833884

  20. One-Pot Synthesis of CoSex -rGO Composite Powders by Spray Pyrolysis and Their Application as Anode Material for Sodium-Ion Batteries.

    Science.gov (United States)

    Park, Gi Dae; Kang, Yun Chan

    2016-03-14

    A simple one-pot synthesis of metal selenide/reduced graphene oxide (rGO) composite powders for application as anode materials in sodium-ion batteries was developed. The detailed mechanism of formation of the CoSe(x)-rGO composite powders that were selected as the first target material in the spray pyrolysis process was studied. The crumple-structured CoSe(x)-rGO composite powders prepared by spray pyrolysis at 800 °C had a crystal structure consisting mainly of Co0.85 Se with a minor phase of CoSe2. The bare CoSe(x) powders prepared for comparison had a spherical shape and hollow structure. The discharge capacities of the CoSe(x)-rGO composite and bare CoSe(x) powders in the 50th cycle at a constant current density of 0.3 A g(-1) were 420 and 215 mA h g(-1), respectively, and their capacity retentions measured from the second cycle were 80 and 46%, respectively. The high structural stability of the CoSe(x)-rGO composite powders for repeated sodium-ion charge and discharge processes resulted in superior sodium-ion storage properties compared to those of the bare CoSe(x) powders. PMID:26864320

  1. Anodic bonded graphene

    Energy Technology Data Exchange (ETDEWEB)

    Balan, Adrian; Kumar, Rakesh; Boukhicha, Mohamed; Beyssac, Olivier; Bouillard, Jean-Claude; Taverna, Dario; Sacks, William; Shukla, Abhay [Universite Pierre et Marie Curie-Paris 6, CNRS-UMR7590, Institut de Mineralogie et de Physique des Milieux Condenses, 140 rue de Lourmel, Paris, F-75015 France (France); Marangolo, Massimiliano; Lacaze, Emanuelle; Gohler, Roger [Universite Pierre et Marie Curie-Paris 6, CNRS-UMR7588, Institut des Nanosciences de Paris, 140 rue de Lourmel, Paris, F-75015 France (France); Escoffier, Walter; Poumirol, Jean-Marie, E-mail: abhay.shukla@upmc.f [Laboratoire National des Champs Magnetiques Intenses, INSA UPS CNRS, UPR 3228, Universite de Toulouse, 143 avenue de Rangueil, 31400 Toulouse (France)

    2010-09-22

    We show how to prepare graphene samples on a glass substrate with the anodic bonding method. In this method, a graphite precursor in flake form is bonded to a glass substrate with the help of an electrostatic field and then cleaved off to leave few layer graphene on the substrate. Now that several methods are available for producing graphene, the relevance of our method is in its simplicity and practicality for producing graphene samples of about 100 {mu}m lateral dimensions. This method is also extensible to other layered materials. We discuss some detailed aspects of the fabrication and results from Raman spectroscopy, local probe microscopy and transport measurements on these samples.

  2. Carbon-Rich Silicon Oxycarbide (SiOC) and Silicon Oxycarbide/Element (SiOC/X, X= Si, Sn) Nano-Composites as New Anode Materials for Li-Ion Battery Application

    OpenAIRE

    Kaspar, Jan

    2014-01-01

    Carbon-rich silicon oxycarbide (SiOC) and silicon oxycarbide/element nano-composites (SiOC/X, X=Si, Sn) are prepared via thermal conversion of polyorganosiloxanes and studied as potential anode material for Li-ion battery application. The obtained materials are characterized by various chemical, structural, electrochemical and electro-analytical methods. The chemical composition and microstructure of the samples is analyzed and correlated with their electrochemical properties and performance....

  3. Polymer-derived-SiCN ceramic/graphite composite as anode material with enhanced rate capability for lithium ion batteries

    Science.gov (United States)

    Graczyk-Zajac, M.; Fasel, C.; Riedel, R.

    2011-08-01

    We report on a new composite material in view of its application as a negative electrode in lithium-ion batteries. A commercial preceramic polysilazane mixed with graphite in 1:1 weight ratio was transformed into a SiCN/graphite composite material through a pyrolytic polymer-to-ceramic conversion at three different temperatures, namely 950 °C, 1100 °C and 1300 °C. By means of Raman spectroscopy we found successive ordering of carbon clusters into nano-crystalline graphitic regions with increasing pyrolysis temperature. The reversible capacity of about 350 mAh g-1 was measured with constant current charging/discharging for the composite prepared at 1300 °C. For comparison pure graphite and pure polysilazane-derived SiCN ceramic were examined as reference materials. During fast charging and discharging the composite material demonstrates enhanced capacity and stability. Charging and discharging in half an hour lead to about 200 and 10 mAh g-1, for the composite annealed at 1300 °C and pure graphite, respectively. A clear dependence between the final material capacity and pyrolysis temperature is found and discussed with respect to possible application in batteries, i.e. practical discharging potential limit. The best results in terms of capacity recovered under 1 V and high rate capability were also obtained for samples synthesized at 1300 °C.

  4. Synthesis of Carbon-coated Nanoplate α-Na2MoO4 and its Electrochemical Lithiation Process as Anode Material for Lithium-ion Batteries

    International Nuclear Information System (INIS)

    Highlights: • Na2MoO4 is firstly valuated as an anode material for lithium-ion batteries. • Carbon-coated nanoplate α-Na2MoO4 sample is synthesized firstly via a facile sol–gel method. • Residual carbon and reducing atmosphere would not change the valence of Mo (+6). • Carbon-coated nanoplate α-Na2MoO4 presents outstanding rate abilities and cycle capabilities compared to the carbon-free sample. • The Li storage mechanism of α-Na2MoO4 is conversion reaction confirmed by the ex-situ XRD and HRTEM results. - Abstract: The carbon-coated α-Na2MoO4 nanoplate sample was fabricated via a facile sol–gel method involving the subsequent annealing under a reducing atmosphere to decompose the organic carbon source. X-ray diffraction with Rietveld refinement, high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) results show that single-phase α-Na2MoO4 can be obtained even under the presence of carbon and reducing atmosphere. When evaluated as an anode material for lithium-ion batteries, the carbon-coated α-Na2MoO4 nanoplate electrode displays a discharge and recharge capacity of 806 mAh g−1 and 409 mAh g−1 respectively in the first cycle, while a reversible discharge–charge capacity of 350 mAh g−1 can be retained after 30 cycles at 30 mAh g−1. A capacity of ∼320 mAh g−1 at 30 mAh g−1 can still recover after 50 cycles even following the discharge/charge process with the high current density of 480 mAh g−1. Meanwhile, carbon-free and carbon-coated α-Na2MoO4 powders fabricated via a solid state reaction were also prepared for comparison. Furthermore, the structure change of α-Na2MoO4 and its Li storage mechanism upon lithiation and delithiation process are studied by ex-situ XRD and TEM in below

  5. NASICON-Structured NaTi2(PO4)3@C Nanocomposite as the Low Operation-Voltage Anode Material for High-Performance Sodium-Ion Batteries.

    Science.gov (United States)

    Wang, Dongxue; Liu, Qiang; Chen, Chaoji; Li, Malin; Meng, Xing; Bie, Xiaofei; Wei, Yingjin; Huang, Yunhui; Du, Fei; Wang, Chunzhong; Chen, Gang

    2016-01-27

    NASICON-type structured NaTi2(PO4)3 (NTP) has attracted wide attention as a promising anode material for sodium-ion batteries (SIBs), whereas it still suffer from poor rate capability and cycle stability due to the low electronic conductivity. Herein, the architecture, NTP nanoparticles embedded in the mesoporous carbon matrix, is designed and realized by a facile sol-gel method. Different than the commonly employed potentials of 1.5-3.0 V, the Na(+) storage performance is examined at low operation voltages between 0.01 and 3.0 V. The electrode demonstrates an improved capacity of 208 mAh g(-1), one of the highest capacities in the state-of-the-art titanium-based anode materials. Besides the high working plateau at 2.1 V, another one is observed at approximately 0.4 V for the first time due to further reduction of Ti(3+) to Ti(2+). Remarkably, the anode exhibits superior rate capability, whose capacity and corresponding capacity retention reach 56 mAh g(-1) and 68%, respectively, over 10000 cycles under the high current density of 20 C rate (4 A g(-1)). Worthy of note is that the electrode shows negligible capacity loss as the current densities increase from 50 to 100 C, which enables NTP@C nanocomposite as the prospective anode of SIBs with ultrahigh power density. PMID:26720111

  6. Effect of the Side Chains and Anode Material on Thermal Stability and Performance of Bulk-Heterojunction Solar Cells Using DPP(TBFu2 Derivatives as Donor Materials

    Directory of Open Access Journals (Sweden)

    Alexander Kovalenko

    2015-01-01

    Full Text Available An optimized fabrication of bulk-heterojunction solar cells (BHJ SCs based on previously reported diketopyrrolopyrrole donor, ethyl-hexylated DPP(TBFu2, as well as two new DPP(TBFu2 derivatives with ethyl-hexyl acetate and diethyl acetal solubilizing side-chains and PC60BM as an acceptor is demonstrated. Slow gradual annealing of the solar cell causing the effective donor-acceptor reorganization, and as a result higher power conversion efficiency (PCE, is described. By replacing a hole transporting layer PEDOT:PSS with MoO3 we obtained higher PCE values as well as higher thermal stability of the anode contact interface. DPP(TBFu2 derivative containing ethyl-hexyl acetate solubilizing side-chains possessed the best as-cast self-assembly and high crystallinity. However, the presence of ethyl-hexyl acetate and diethyl acetal electrophilic side-chains stabilizes HOMO energy of isolated DPP(TBFu2 donors with respect to the ethyl-hexylated one, according to cyclic voltammetry.

  7. Studies of Nano-sized Co3O4 as Anode Materials for Lithium-ion Batteries

    Institute of Scientific and Technical Information of China (English)

    HUANG, Fenga; ZHAN, Hui; ZHOU, Yun-Hong

    2003-01-01

    The structural evolution of the Co3O4 fine powders prepared by rheological phase reaction and pyrolysis method upon different temperature has been investigated using X-ray diffraction (XRD) topography. The electrochemical performance of Co3O4electrode materials for Li-ion batteries is studied in the form of Li/Co3O4 cells. The reversible capacity as high as 930 mAh/g for the Co3O4 sample heat-treated at 600 C is achieved and sustained over 30 times charge-discharge cycles at room temperature. The detailed information concerning the reaction mechanism of Co3O4 active material together with lithium ion is obtained through ex-situ XRD topography, X-ray photoelectron spectroscopy (XPS) analysis and cyclic voltammetry (CV) technique. And it is revealed that a "two-step" reaction is involved in the charge and discharge of the Li/Co3O4 cells, in which Co3O4 active material is reversibly reduced into xCo·(3 - x )CoO and then into metallic Co.

  8. Improved electrochemical performance of Ag-modified Li4Ti5O12 anode material in a broad voltage window

    Indian Academy of Sciences (India)

    Yan-Rong Zhu; Ting-Feng Yi; Hong-Tao Ma; Yong-Quan Ma; Li-Juan Jiang; Rong-Sun Zhu

    2014-01-01

    Li4Ti5O12/Ag composites were synthesized by a solid-state method. The effect of Ag modification on the physical and electrochemical properties is discussed by the characterizations of X-ray diffraction, scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy, cycling and rate tests. The lattice parameter of Li4Ti5O12 with a low Ag content is almost not changed, but the lattice parameter becomes larger due to the high content of Ag. Li4Ti5O12/Ag material has a uniform particle size which is about 1 m. Modification of appropriate Ag is beneficial to the reversible intercalation and deintercalation of Li+. Modification of Ag not only decreases the charge transfer resistance of Li4Ti5O12 material, but also improves the diffusion coefficient of lithium ion. Li4Ti5O12/Ag (3 mass%) material has the lowest charge transfer resistance, the highest diffusion coefficient of lithium ion and the best rate cycling performance.

  9. Self-assembled three-dimensional hierarchical NiO nano/microspheres as high-performance anode material for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Pengpeng [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Zhao, Hailei, E-mail: hlzhao@ustb.edu.cn [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Beijing Key Lab of New Energy Materials and Technologies, Beijing 100083 (China); Zeng, Zhipeng; Gao, Chunhui; Liu, Xin; Zhang, Tianhou [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China)

    2015-02-28

    Highlights: • 3D hierarchical NiO porous nano/microspheres were prepared via a hydrothermal route. • Loose NiO microsphere is composed of a large number of cross-linked nanoparticles. • A possible self-assembly mechanism is illustrated in detail. • High specific capacity, good cycleability and superior rate-capability are achieved. - Abstract: Self-assembled three-dimensional hierarchical NiO nano/microspheres were fabricated via a hydrothermal route. The obtained NiO presents a micro-sized porous spherical morphology which is composed of a large number of primary NiO nanoparticles linked together with an ordered fashion. As anode material for lithium ion batteries, NiO nano/microspheres exhibit stable reversible capacity of over 700 mAh g{sup −1} and good rate capability. The superior electrochemical performance could be attributed to the merits of the unique three-dimensional hierarchical porous nano/microstructure.

  10. Graphitic Carbon-Coated FeSe2 Hollow Nanosphere-Decorated Reduced Graphene Oxide Hybrid Nanofibers as an Efficient Anode Material for Sodium Ion Batteries

    Science.gov (United States)

    Cho, Jung Sang; Lee, Jung-Kul; Kang, Yun Chan

    2016-01-01

    A novel one-dimensional nanohybrid comprised of conductive graphitic carbon (GC)-coated hollow FeSe2 nanospheres decorating reduced graphene oxide (rGO) nanofiber (hollow nanosphere FeSe2@GC–rGO) was designed as an efficient anode material for sodium ion batteries and synthesized by introducing the nanoscale Kirkendall effect into the electrospinning method. The electrospun nanofibers transformed into hollow nanosphere FeSe2@GC–rGO hybrid nanofibers through a Fe@GC–rGO intermediate. The discharge capacities of the bare FeSe2 nanofibers, nanorod FeSe2–rGO–amorphous carbon (AC) hybrid nanofibers, and hollow nanosphere FeSe2@GC–rGO hyrbid nanofibers at a current density of 1 A g−1 for the 150th cycle were 63, 302, and 412 mA h g−1, respectively, and their corresponding capacity retentions measured from the 2nd cycle were 11, 73, and 82%, respectively. The hollow nanosphere FeSe2@GC–rGO hybrid nanofibers delivered a high discharge capacity of 352 mA h g−1 even at an extremely high current density of 10 A g−1. The enhanced electrochemical properties of the hollow nanosphere FeSe2@GC–rGO composite nanofibers arose from the synergetic effects of the FeSe2 hollow morphology and highly conductive rGO matrix. PMID:27033096

  11. One-pot solvothermal synthesis of graphene wrapped rice-like ferrous carbonate nanoparticles as anode materials for high energy lithium-ion batteries

    Science.gov (United States)

    Zhang, Fan; Zhang, Ruihan; Feng, Jinkui; Ci, Lijie; Xiong, Shenglin; Yang, Jian; Qian, Yitai; Li, Lifei

    2014-11-01

    Well dispersed rice-like FeCO3 nanoparticles were produced and combined with reduced graphene oxide (RGO) via a one-pot solvothermal route. SEM characterization shows that rice-like FeCO3 nanoparticles are homogeneously anchored on the surface of the graphene nanosheets; the addition of RGO is helpful to form a uniform morphology and reduce the particle size of FeCO3 to nano-grade. As anode materials for lithium-ion batteries, the FeCO3/RGO nanocomposites exhibit significantly improved lithium storage properties with a large reversible capacity of 1345 mA h g-1 for the first cycle and a capacity retention of 1224 mA h g-1 after 50 cycles with a good rate capability compared with pure FeCO3 particles. The superior electrochemical performance of the FeCO3/RGO nanocomposite electrode compared to the pure FeCO3 electrode can be attributed to the well dispersed RGO which enhances the electronic conductivity and accommodates the volume change during the conversion reactions. Our study shows that the FeCO3/RGO nanocomposite could be a suitable candidate for high capacity lithium-ion batteries.

  12. Large-scale synthesis of macroporous SnO2 with/without carbon and their application as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: → A new hard template prepared from glucose was used to synthesize macroporous SnO2. → SnO2 and SnO2/C were prepared in a simple and large-scale synthetic method. → Combining the nanostructure design and active/inactive nanocomposite concept. → The obtained SnO2/C composite exhibited superior cycling performance. - Abstract: The macroporous SnO2 is prepared using close packed carbonaceous sphere template which synthesized from glucose by hydrothermal method. The structure and morphology of the macroporous SnO2 are evaluated by XRD and FE-SEM. The average pore size of the macroporous SnO2 is about 190 nm and its wall thickness is less than 10 nm. When the macroporous SnO2 filled with carbon is used as an anode material for lithium-ion battery, the capacity is about 380 mAh g-1 after 70 cycles. The improved cyclability is attributed to the carbon matrix which is used as an effective physical buffer to prevent the collapse of the well dispersed macroporous SnO2.

  13. Large-scale synthesis of macroporous SnO{sub 2} with/without carbon and their application as anode materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang Fei; Yao Gang; Xu Minwei [MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi' an Jiaotong University, Shaan Xi 710049 (China); Zhao Mingshu, E-mail: zhaomshu@mail.xjtu.edu.cn [MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi' an Jiaotong University, Shaan Xi 710049 (China); Sun Zhanbo [MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi' an Jiaotong University, Shaan Xi 710049 (China); Song Xiaoping, E-mail: xpsong@mail.xjtu.edu.cn [MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi' an Jiaotong University, Shaan Xi 710049 (China)

    2011-05-19

    Highlights: > A new hard template prepared from glucose was used to synthesize macroporous SnO{sub 2}. > SnO{sub 2} and SnO{sub 2}/C were prepared in a simple and large-scale synthetic method. > Combining the nanostructure design and active/inactive nanocomposite concept. > The obtained SnO{sub 2}/C composite exhibited superior cycling performance. - Abstract: The macroporous SnO{sub 2} is prepared using close packed carbonaceous sphere template which synthesized from glucose by hydrothermal method. The structure and morphology of the macroporous SnO{sub 2} are evaluated by XRD and FE-SEM. The average pore size of the macroporous SnO{sub 2} is about 190 nm and its wall thickness is less than 10 nm. When the macroporous SnO{sub 2} filled with carbon is used as an anode material for lithium-ion battery, the capacity is about 380 mAh g{sup -1} after 70 cycles. The improved cyclability is attributed to the carbon matrix which is used as an effective physical buffer to prevent the collapse of the well dispersed macroporous SnO{sub 2}.

  14. Electrochemical performance of potassium-doped wüstite nanoparticles supported on graphene as an anode material for lithium ion batteries

    Science.gov (United States)

    Jung, Dong-Won; Jeong, Jae-Hoon; Han, Sang-Wook; Oh, Eun-Suok

    2016-05-01

    A graphene composite with potassium-doped FeO nanoparticles (K-FeO/graphene) is synthesized by the thermal diffusion of potassium into Fe2O3/graphene using polyol reduction. This is applied as anode material in lithium ion batteries in order to enhance the electrochemical performance of conventional iron oxides (hematite or magnetite). Rhombohedral Fe2O3 crystals are transformed into face-centered cubic FeO crystals, which show a broad d-spacing (5.2 Å) between their (111) crystal planes, by the calcination of potassium-added Fe2O3/graphene. Because of its structural characteristics, the K-FeO/graphene composite demonstrates an excellent discharge capacity of 1776 mA h g-1 at the 50th cycle at a current of 100 mA h g-1 with stable capacity retention. Even with the very high current density of 18.56 A g-1, its capacity remains at 851 mA h g-1 after 800 cycles.

  15. Mesoporous MFe2O4 (M = Mn, Co, and Ni) for anode materials of lithium-ion batteries: Synthesis and electrochemical properties

    International Nuclear Information System (INIS)

    Highlights: • MFe2O4 (M = Mn, Co, and Ni) are synthesized by a template-free hydrothermal method. • The mesoporous morphology is formed by self-assembly of crystal nucleus. • The mesporous MnFe2O4 have the active phase and the synergy for Li-ion storage. - Abstract: The MFe2O4 (M = Mn, Co, and Ni) mesoporous spheres with an average diameter of 250 nm were synthesized through a template-free hydrothermal method. The mesoporous MnFe2O4 with a large surface area of 87.5 m2/g and an average pore size of 27.52 nm were obtained. As the anode materials for Li-ion batteries, the mesoporous MnFe2O4 exhibits excellent initial charge and discharge capacities of 1010 and 642.5 mA h/g. After 50 cycles, the discharge capacity could still remain at 379 mA h/g. The results showed that the active phase and the synergy between different metal oxides greatly improved the electrochemical performance, and the mesoporous composite could stabilize the structure of the electrodes

  16. Facile synthesis of porous NiCo2O4 microflowers as high-performance anode materials for advanced lithium-ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: - Abstract: Porous NiCo2O4 microflowers having very high Brunner-Emmett-Teller (BET) surface area (∼109.283 m2/g) are fabricated by a facile solvothermal method followed by calcinating the Co-Ni hydroxides precursor in air. The as-prepared porous NiCo2O4 microflowers exhibit excellent cycling stability (952 mA h g−1 at a current density of 100 mA g−1 after 60 cycles and 720 mA h g−1 at a current density of 500 mA g−1 after 100 cycles). This outstanding electrochemical performance is attributed to the unique hierarchical structure and high porosity, which can provide enough space to buffer the volume expansion during the discharge and charge processes, increase the contact area between the electrode and electrolyte, and reduce the transport lengths of both lithium ions and electrons. The porous NiCo2O4 microflowers show great potential in high-capacity anode materials for next-generation lithium-ion batteries

  17. Ultrasonication-assisted ultrafast preparation of multiwalled carbon nanotubes/Au/Co3O4 tubular hybrids as superior anode materials for oxygen evolution reaction

    Science.gov (United States)

    Fang, Yiyun; Li, Xinzhe; Hu, Yiping; Li, Feng; Lin, Xiaoqing; Tian, Min; An, Xingcai; Fu, Yan; Jin, Jun; Ma, Jiantai

    2015-12-01

    Efficient and simple operation electrocatalysts for the oxygen evolution reaction (OER) are essential components of renewable energy technologies. Here, a novel, simple, and efficient routine is presented for the first time by constructing a high-efficiency anode catalyst for OER. With the aid of high intensity ultrasound, a uniformly loading, conductive multiwalled carbon nanotubes/metal/transition metal-oxide (CNTs-Au@Co3O4) tubular hybrids is synthesized. In alkaline media, the materials catalyze OER with an onset potential of 1.56 V vs. reversible hydrogen electrode (RHE) and overpotential only of 350 mV to achieve a stable current density of 10 mA cm-2 for at least 25 h. The unusual catalytic activity and stability is due to the following elements. Firstly, the tubular architecture not only provides sufficient active centers for OER, but also improves rapid mass/charge transport. Secondly, Co3O4 layer protects Au nanoparticles (NPs) against detachment. In addition, we also prove that the highest electronegativity metal Au accelerate the formation of catalytic active sites of CoIV species for OER. It is believed that this simple preparation method paves a way to fabricate a range of CNTs/metal/metal-oxide based composites as superior OER catalysts.

  18. Hydrogenated TiO2 Branches Coated Mn3O4 Nanorods as an Advanced Anode Material for Lithium Ion Batteries.

    Science.gov (United States)

    Wang, Nana; Yue, Jie; Chen, Liang; Qian, Yitai; Yang, Jian

    2015-05-20

    Rational design and delicate control on the component, structure, and surface of electrodes in lithium ion batteries are highly important to their performances in practical applications. Compared with various components and structures for electrodes, the choices for their surface are quite limited. The most widespread surface for numerous electrodes, a carbon shell, has its own issues, which stimulates the desire to find another alternative surface. Here, hydrogenated TiO2 is exemplified as an appealing surface for advanced anodes by the growth of ultrathin hydrogenated TiO2 branches on Mn3O4 nanorods. High theoretical capacity of Mn3O4 is well matched with low volume variation (∼4%), enhanced electrical conductivity, good cycling stability, and rate capability of hydrogenated TiO2, as demonstrated in their electrochemical performances. The proof-of-concept reveals the promising potential of hydrogenated TiO2 as a next-generation material for the surface in high-performance hybrid electrodes. PMID:25928277

  19. Porous γ-Fe2O3 spheres coated with N-doped carbon from polydopamine as Li-ion battery anode materials

    Science.gov (United States)

    Liang, Jin; Xiao, Chunhui; Chen, Xu; Gao, Ruixia; Ding, Shujiang

    2016-05-01

    Nitrogen doping has been demonstrated to play a crucial role in controlling the electronic properties of carbon-based composites. In this paper, nitrogen-doped carbon coated γ-Fe2O3 (NC@γ-Fe2O3) composite was successfully fabricated through a facile and high-yield strategy, including a hydrothermal reaction process for porous γ-Fe2O3 and a subsequent coating of nitrogen-doped carbon by using dopamine as precursor. The resulting composite combines the superior properties of porous Fe2O3 and heteroatom-doped conductive carbon layer derived from polydopamine. When used as the anode material of the lithium-ion battery, the as-prepared NC@γ-Fe2O3 composite exhibits excellent lithium storage properties in terms of high capacity, stable cycling performance (869.6 mAh g‑1 at the current density of 0.5 A g‑1 after 150 cycles) and excellent rate capability.

  20. One-Pot Fabrication of Hierarchical Nanosheet-Based TiO2 -Carbon Hollow Microspheres for Anode Materials of High-Rate Lithium-Ion Batteries.

    Science.gov (United States)

    Jin, Zhaokui; Yang, Mu; Wang, Jingjing; Gao, Hongyi; Lu, Yunfeng; Wang, Ge

    2016-04-18

    Hierarchical and hollow nanostructures have recently attracted considerable attention because of their fantastic architectures and tunable property for facile lithium ion insertion and good cycling stability. In this study, a one-pot and unusual carving protocol is demonstrated for engineering hollow structures with a porous shell. Hierarchical TiO2 hollow spheres with nanosheet-assembled shells (TiO2 NHS) were synthesized by the sequestration between the titanium source and 2,2'-bipyridine-5,5'-dicarboxylic acid, and kinetically controlled etching in trifluoroacetic acid medium. In addition, annealing such porous nanostructures presents the advantage of imparting carbon-doped functional performance to its counterpart under different atmospheres. Such highly porous structures endow very large specifics surface area of 404 m(2)  g(-1) and 336 m(2)  g(-1) for the as-prepared and calcination under nitrogen gas. C/TiO2 NHS has high capacity of 204 mA h g(-1) at 1 C and a reversible capacity of 105 mA h g(-1) at a high rate of 20 C, and exhibits good cycling stability and superior rate capability as an anode material for lithium-ion batteries. PMID:26970239

  1. Graphitic Carbon-Coated FeSe2 Hollow Nanosphere-Decorated Reduced Graphene Oxide Hybrid Nanofibers as an Efficient Anode Material for Sodium Ion Batteries

    Science.gov (United States)

    Cho, Jung Sang; Lee, Jung-Kul; Kang, Yun Chan

    2016-04-01

    A novel one-dimensional nanohybrid comprised of conductive graphitic carbon (GC)-coated hollow FeSe2 nanospheres decorating reduced graphene oxide (rGO) nanofiber (hollow nanosphere FeSe2@GC–rGO) was designed as an efficient anode material for sodium ion batteries and synthesized by introducing the nanoscale Kirkendall effect into the electrospinning method. The electrospun nanofibers transformed into hollow nanosphere FeSe2@GC–rGO hybrid nanofibers through a Fe@GC–rGO intermediate. The discharge capacities of the bare FeSe2 nanofibers, nanorod FeSe2–rGO–amorphous carbon (AC) hybrid nanofibers, and hollow nanosphere FeSe2@GC–rGO hyrbid nanofibers at a current density of 1 A g‑1 for the 150th cycle were 63, 302, and 412 mA h g‑1, respectively, and their corresponding capacity retentions measured from the 2nd cycle were 11, 73, and 82%, respectively. The hollow nanosphere FeSe2@GC–rGO hybrid nanofibers delivered a high discharge capacity of 352 mA h g‑1 even at an extremely high current density of 10 A g‑1. The enhanced electrochemical properties of the hollow nanosphere FeSe2@GC–rGO composite nanofibers arose from the synergetic effects of the FeSe2 hollow morphology and highly conductive rGO matrix.

  2. Facile preparation of 3D hierarchical porous carbon from lignin for the anode material in lithium ion battery with high rate performance

    International Nuclear Information System (INIS)

    Graphical abstract: Hierarchical porous carbon with 3D macroporous structure is prepared via a facile method and displays high lithium ion storage capacity and rate capability. - Highlights: • Hierarchical porous carbon is prepared from lignin via a facile method. • KOH acts both as activating agent and template in the preparation process. • Lignin based hierarchical porous carbon displays high lithium storage capacity. • Lignin based hierarchical porous carbon displays stable cycling stability. - Abstract: Hierarchical porous carbon derived from lignin (denoted as LHPC) was prepared via a facile method. In this method, KOH acts both as activating agent and template. The obtained LHPC was composed of unique 3D macroporous network with mesopores and micropores decorated on carbon walls. LHPC was further applied as the anode material of lithium ion battery and displayed a stable, high capacity of 470 mAh g−1 after 400 galvanostatic charge-discharge cycles at a current density of 200 mA g−1. Furthermore, LHPC displayed high cycling stability and perfect rate capability. This facile method for the preparation of LHPC offers a new route for the preparation of a series of hierarchical porous carbons for the application in supercapacitors, fuel cells, lithium ion batteries, etc

  3. Investigation of a porous NiSi2/Si composite anode material used for lithium-ion batteries by X-ray absorption spectroscopy

    Science.gov (United States)

    Zhou, Dong; Jia, Haiping; Rana, Jatinkumar; Placke, Tobias; Klöpsch, Richard; Schumacher, Gerhard; Winter, Martin; Banhart, John

    2016-08-01

    Local structural changes in a porous NiSi2/Si composite anode material are investigated by X-ray absorption spectroscopy. It is observed that the NiSi2 phase shows a strong metal-metal bond character and no clear changes can be observed in XANES during lithiation and de-lithiation. The variation of the number of nearest neighbors of the Ni atom for the 1st coordinate Ni-Si shell and σ2 in the 1st cycle, both determined by refinement, demonstrates that NiSi2 can partially react with lithium during discharge and charge. A partially reversible non-stoichiometric compound NiSi2-y is formed during cell operation, the crystal structure of which is the same as that of the NiSi2 phase. It can be concluded that NiSi2 in the composite not only accommodates the pronounced volume changes caused by the lithium uptake into silicon, but also contributes to the reversible capacity of the cell.

  4. Template-free electrodeposition of AlFe alloy nanowires from a room-temperature ionic liquid as an anode material for Li-ion batteries.

    Science.gov (United States)

    Chen, Gang; Chen, Yuqi; Guo, Qingjun; Wang, Heng; Li, Bing

    2016-08-15

    AlFe alloy nanowires were directly electrodeposited on copper substrates from trimethylamine hydrochloride (TMHC)-AlCl3 ionic liquids with small amounts of FeCl3 at room temperature without templates. Coin cells composed of AlFe alloy nanowire electrodes and lithium foils were assembled to characterize the alloy electrochemical properties by galvanostatic charge/discharge tests. Effects of FeCl3 concentration, potential and temperature on the alloy morphology, composition and cyclic performance were examined. Addition of Fe into the alloy changed the nanowires from a 'hill-like' bulk morphology to a free-standing morphology, and increased the coverage area of the alloy on Cu substrates. As an inactive element, Fe could also buffer the alloys' large volume changes during Li intercalation and deintercalation. AlFe alloy nanowires composed of a small amount of Fe with an average diameter of 140 nm exhibited an outstanding cyclic performance and delivered a specific capacity of about 570 mA h g(-1) after 50 cycles. This advanced template-free method for the direct preparation of high performance nanostructure AlFe alloy anode materials is quite simple and inexpensive, which presents a promising prospect for practical application in Li-ion batteries. PMID:27200436

  5. Co3V2O8 Sponge Network Morphology Derived from Metal-Organic Framework as an Excellent Lithium Storage Anode Material.

    Science.gov (United States)

    Soundharrajan, Vaiyapuri; Sambandam, Balaji; Song, Jinju; Kim, Sungjin; Jo, Jeonggeun; Kim, Seokhun; Lee, Seulgi; Mathew, Vinod; Kim, Jaekook

    2016-04-01

    Metal-organic framework (MOF)-based synthesis of battery electrodes has presntly become a topic of significant research interest. Considering the complications to prepare Co3V2O8 due to the criticality of its stoichiometric composition, we report on a simple MOF-based solvothermal synthesis of Co3V2O8 for use as potential anodes for lithium battery applications. Characterizations by X-ray diffraction, X-ray photoelectron spectroscopy, high resolution electron microscopy, and porous studies revealed that the phase pure Co3V2O8 nanoparticles are interconnected to form a sponge-like morphology with porous properties. Electrochemical measurements exposed the excellent lithium storage (∼1000 mAh g(-1) at 200 mA g(-1)) and retention properties (501 mAh g(-1) at 1000 mA g(-1) after 700 cycles) of the prepared Co3V2O8 electrode. A notable rate performance of 430 mAh g(-1) at 3200 mA g(-1) was also observed, and ex situ investigations confirmed the morphological and structural stability of this material. These results validate that the unique nanostructured morphology arising from the use of the ordered array of MOF networks is favorable for improving the cyclability and rate capability in battery electrodes. The synthetic strategy presented herein may provide solutions to develop phase pure mixed metal oxides for high-performance electrodes for useful energy storage applications. PMID:26983348

  6. A novel radial anode layer ion source for inner wall pipe coating and materials modification--hydrogenated diamond-like carbon coatings from butane gas.

    Science.gov (United States)

    Murmu, Peter P; Markwitz, Andreas; Suschke, Konrad; Futter, John

    2014-08-01

    We report a new ion source development for inner wall pipe coating and materials modification. The ion source deposits coatings simultaneously in a 360° radial geometry and can be used to coat inner walls of pipelines by simply moving the ion source in the pipe. Rotating parts are not required, making the source ideal for rough environments and minimizing maintenance and replacements of parts. First results are reported for diamond-like carbon (DLC) coatings on Si and stainless steel substrates deposited using a novel 360° ion source design. The ion source operates with permanent magnets and uses a single power supply for the anode voltage and ion acceleration up to 10 kV. Butane (C4H10) gas is used to coat the inner wall of pipes with smooth and homogeneous DLC coatings with thicknesses up to 5 μm in a short time using a deposition rate of 70 ± 10 nm min(-1). Rutherford backscattering spectrometry results showed that DLC coatings contain hydrogen up to 30 ± 3% indicating deposition of hydrogenated DLC (a-C:H) coatings. Coatings with good adhesion are achieved when using a multiple energy implantation regime. Raman spectroscopy results suggest slightly larger disordered DLC layers when using low ion energy, indicating higher sp(3) bonds in DLC coatings. The results show that commercially interesting coatings can be achieved in short time. PMID:25173323

  7. Synthesis and electrochemical properties of porous double-shelled Mn2O3 hollow microspheres as a superior anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Double-shelled Mn2O3 hollow microspheres are prepared by a multi-step. • synthesis procedure. • Solid, hollow and yolk-structured Mn2O3 spheres are prepared for comparison. • The double-shelled hollow Mn2O3 is superior in electrochemical properties. - Abstract: By means of a specially designed multi-step synthesis procedure involving steps of precipitation, controlled oxidation, selective etching and calcination, porous double-shelled Mn2O3 hollow microspheres are synthesized. Solid, hollow and yolk-structured Mn2O3 are also similarly synthesized for comparison. X-ray diffraction, scanning and transmission electron microscopies, IR spectroscopy, thermogravimetry, and Brunauer-Emmett-Teller measurements are employed to investigate their structures and compositions. Galvanostatic cell cycling and impedance spectroscopy are used to characterize the electrochemical properties of Mn2O3/Li cells. The results show that the hierarchical hollow structured (double-shelled, hollow and yolk-structured) Mn2O3 anode materials deliver higher reversible capacities and excellent cycling stabilities than the solid Mn2O3. Moreover, among the three hierarchical hollow structured samples, the double shelled sample possesses the best cycling performance, especially at a high current density

  8. Effect of nitrogen on the electrochemical performance of core–shell structured Si/C nanocomposites as anode materials for Li-ion batteries

    International Nuclear Information System (INIS)

    Highlights: ► N-containing core–shell structured Si/C nanocomposites are prepared via two steps. ► The N-containing Si/C nanocomposites exhibit high capacity and excellent cycling stability. ► The appropriate nitrogen has a beneficial effect on the electrochemical performance. -- Abstract: Core–shell structured Si/C nanocomposites with different nitrogen contents are prepared by in situ polymerization of aniline in the suspension of silicon nanoparticles followed by carbonization of Si/polyaniline (PANI) nanocomposites at different temperatures. The nitrogen contents of Si/C nanocomposites decrease gradually with increasing carbonization temperatures. The effect of nitrogen contents on the electrochemical performance of Si/C nanocomposites as anode materials for lithium ion batteries is investigated. It is found that the Si/C nanocomposites with 4.75 wt.% nitrogen exhibit the high specific capacity of 795 mAh g−1 after 50 cycles at a current density of 100 mA g−1 and excellent cycling stability. The appropriate nitrogen in Si/C nanocomposites plays a beneficial role in the improvement of electrochemical performance. The nitrogen in Si/C nanocomposites increases the reversible capacity, which may be due to the formation of vacancies and dangling bonds around the nitrogen sites

  9. A large-scale, green route to synthesize of leaf-like mesoporous CuO as high-performance anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Mesoporous leaf-like CuO was scalable synthesized using commercial Cu(OH)2 at room temperature. • The sample has a high surface area of 23.55 m2 g−1 and narrow pore distribution of 3.3 nm. • After 300 cycles, the CuO still kept a capacity of 694.7 mAh g−1 at 500 mAh g−1. - Abstract: Herein, leaf-like CuO with mesoporous structure has been synthesized by treating commercial Cu(OH)2 powder at room temperature for an appropriate time. The BET measurement shows that the obtained CuO has a high surface area of 23.55 m2 g−1 and narrow pore distribution peaking at about 3.3 nm. The electrochemical performances of leaf-like mesoporous CuO are evaluated by cyclic voltammetry and galvanostatic charge-discharge studies. Electrochemical results show that the as-prepared CuO are promising anode materials in LIBs including high specific capacity, good retention and rate property. Even at the high current density of 2000 mA g−1, the mesoporous CuO electrode still can maintain a specific capacity of 490.5 mAh g−1 which is much higher than the theoretical specific capacity of graphite (372 mAh g−1)

  10. Preparation of a Binder-Free Three-Dimensional Carbon Foam/Silicon Composite as Potential Material for Lithium Ion Battery Anodes.

    Science.gov (United States)

    Roy, Amit K; Zhong, Mingjie; Schwab, Matthias Georg; Binder, Axel; Venkataraman, Shyam S; Tomović, Željko

    2016-03-23

    We report a novel three-dimensional nitrogen containing carbon foam/silicon (CFS) composite as potential material for lithium ion battery anodes. Carbon foams were prepared by direct carbonization of low cost, commercially available melamine formaldehyde (MF, Basotect) foam precursors. The carbon foams thus obtained display a three-dimensional interconnected macroporous network structure with good electrical conductivity (0.07 S/cm). Binder free CFS composites used for electrodes were prepared by immersing the as-fabricated carbon foam into silicon nanoparticles dispersed in ethanol followed by solvent evaporation and secondary pyrolysis. In order to substantiate this new approach, preliminary electrochemical testing has been done. The first results on CFS electrodes demonstrated initial capacity of 1668 mAh/g with 75% capacity retention after 30 cycles of subsequent charging and discharging. In order to further enhance the electrochemical performance, silicon nanoparticles were additionally coated with a nitrogen containing carbon layer derived from codeposited poly(acrylonitrile). These carbon coated CFS electrodes demonstrated even higher performance with an initial capacity of 2100 mAh/g with 92% capacity retention after 30 cycles of subsequent charging and discharging. PMID:26909748

  11. Controlled Synthesis of Carbon Nanofibers Anchored with Zn(x)Co(3-x)O4 Nanocubes as Binder-Free Anode Materials for Lithium-Ion Batteries.

    Science.gov (United States)

    Chen, Renzhong; Hu, Yi; Shen, Zhen; Chen, Yanli; He, Xia; Zhang, Xiangwu; Zhang, Yan

    2016-02-01

    The direct growth of complex ternary metal oxides on three-dimensional conductive substrates is highly desirable for improving the electrochemical performance of lithium-ion batteries (LIBs). We herein report a facile and scalable strategy for the preparation of carbon nanofibers (CNFs) anchored with ZnxCo3-xO4 (ZCO) nanocubes, involving a hydrothermal process and thermal treatment. Moreover, the size of the ZCO nanocubes was adjusted by the quantity of urea used in the hydrothermal process. Serving as a binder-free anode material for LIBs, the ZnCo2O4/CNFs composite prepared using 1.0 mmol of urea (ZCO/CNFs-10) exhibited excellent electrochemical performance with high reversible capacity, excellent cycling stability, and good rate capability. More specifically, a high reversible capacity of ∼600 mAh g(-1) was obtained at a current density of 0.5 C following 300 charge-discharge cycles. The excellent electrochemical performance could be associated with the controllable size of the ZCO nanocubes and synergistic effects between ZCO and the CNFs. PMID:26761129

  12. A low-cost and advanced SiOx-C composite with hierarchical structure as an anode material for lithium-ion batteries.

    Science.gov (United States)

    Wu, Wenjun; Shi, Jing; Liang, Yunhui; Liu, Fang; Peng, Yi; Yang, Huabin

    2015-05-28

    A cost-efficient and scalable method is designed to prepare a SiOx-C composite with superior cyclability and excellent rate performance. The glucose addition in a two-step way induces a hierarchical structure, where individual SiOx nanoparticles are wrapped by a conductive carbon layer and these agglomerated particles are further wrapped by a carbon shell functioning as an electrolyte blocking layer. Instrumental analysis indicates that the SiOx domains are comprised of SiO2 and SiO. The SiOx-C anode exhibits a high reversible specific capacity of 674.8 mA h g(-1) after 100 cycles at 100 mA g(-1) with a capacity retention of about 83.5%. The excellent electrochemical performance is due to the hierarchical structure, the well-dispersed conductive carbon network, and the Li2O and Li4SiO4 generated in the initial discharge process, all of which can immensely relieve the volume expansion induced by the lithiation of silicon. This hierarchical SiOx-C composite has a promising prospect of practical application given its adequate storage capacity, good cycling stability, commercially available materials and simple equipment. PMID:25929515

  13. High performance amorphous-Si@SiOx/C composite anode materials for Li-ion batteries derived from ball-milling and in situ carbonization

    Science.gov (United States)

    Wang, Dingsheng; Gao, Mingxia; Pan, Hongge; Wang, Junhua; Liu, Yongfeng

    2014-06-01

    Amorphous-Si@SiOx/C composites with amorphous Si particles as core and coated with a double layer of SiOx and carbon are prepared by ball-milling crystal micron-sized silicon powders and carbonization of the citric acid intruded in the ball-milled Si. Different ratios of Si to citric acid are used in order to optimize the electrochemical performance. It is found that SiOx exists naturally at the surfaces of raw Si particles and its content increases to ca. 24 wt.% after ball-milling. With an optimized Si to citric acid weight ratio of 1/2.5, corresponding to 8.4 wt.% C in the composite, a thin carbon layer is coated on the surfaces of a-Si@SiOx particles, moreover, floc-like carbon also forms and connects the carbon coated a-Si@SiOx particles. The composite provides a capacity of 1450 mA h g-1 after 100 cycles at a current density of 100 mA g1, and a capacity of 1230 mA h g-1 after 100 cycles at 500 mA g1 as anode material for lithium-ion batteries. Effects of ball-milling and the addition of citric acid on the microstructure and electrochemical properties of the composites are revealed and the mechanism of the improvement in electrochemical properties is discussed.

  14. Construction of 3D flower-like MoS2 spheres with nanosheets as anode materials for high-performance lithium ion batteries

    International Nuclear Information System (INIS)

    In this work, we constructed 3D flower-like MoS2 spheres with nanosheets (less than 10 nm) by a simple alcohol-assisted solvothermal route. It was found that the presence of alcohol enhanced the dispersity of MoS2 samples, and the distilled water facilitated the formation of nanosheets through varying the volume ratio of alcohol and distilled water. The prepared MoS2 samples delivered high initial discharge capacity (1346 mA h g−1 at a current density of 100 mA g−1), good coulombic efficiency (77.49% retention for the first cycle and ∼100% for the subsequent cycles), excellent cycling performance (947 mA h g−1 at 100 mA g−1 after 50 cycles) and remarkable rate behavior as anode materials for lithium ion batteries. The superior behavior of MoS2 samples for lithium ion batteries can be ascribed to the thin nanosheets, high specific surface area and their unique layered structure

  15. 锂离子电池硅基负极材料研究进展%Research on the Silicon-Based Anode Material for Lithium Ion Battery

    Institute of Scientific and Technical Information of China (English)

    张利

    2012-01-01

    硅是青海省储量丰富的资源之一,因其储锂容量高、安全性能优越,而成为锂离子电池理想的负极材料,但由于硅在深度嵌脱锂时体积效应大,易与导电介质、集流体失去电接触,造成电极循环性能迅速下降.对抑制其体积效应、增加其电导率的“低维化”和“复合化”两种技术进行了介绍.%Silicon is one of the main resources in Qinghai province. Due to the lower reactivity against e-lectrolyte than lithium and the lower insertion/extraction potential for lithium ion, silicon is an ideal anode material for lithium-ion rechargeable batteries. However,the application of silicon has been hindered by severe volume change upon Ii * insertion and extraction which will cause poor cycling stability. To o-vercome the problems, two main approaches which can realize the alleviation of the severe volume change and the reduction of the charge transfer resistance of silicon have been reviewed.

  16. Synthesis of TiO{sub 2} by electrochemical method from TiCl{sub 4} solution as anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Nur, Adrian, E-mail: adriannur@staff.uns.ac.id; Purwanto, Agus; Jumari, Arif; Dyartanti, Endah R.; Sari, Sifa Dian Permata; Hanifah, Ita Nur [Research Group of Advanced Material, Department of Chemical Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A Kentingan, Surakarta Indonesia 57126 (Indonesia)

    2016-02-08

    Metal oxide combined with graphite becomes interesting composition. TiO{sub 2} is a good candidate for Li ion battery anode because of cost, availability of sufficient materials, and environmentally friendly. TiO{sub 2} gravimetric capacity varied within a fairly wide range. TiO{sub 2} crystals form highly depends on the synthesis method used. The electrochemical method is beginning to emerge as a valuable option for preparing TiO{sub 2} powders. Using the electrochemical method, the particle can easily be controlled by simply adjusting the imposed current or potential to the system. In this work, the effects of some key parameters of the electrosynthesis on the formation of TiO{sub 2} have been investigated. The combination of graphite and TiO{sub 2} particle has also been studied for lithium-ion batteries. The homogeneous solution for the electrosynthesis of TiO{sub 2} powders was TiCl{sub 4} in ethanol solution. The electrolysis was carried out in an electrochemical cell consisting of two carbon electrodes with dimensions of (5 × 2) cm. The electrodes were set parallel with a distance of 2.6 cm between the electrodes and immersed in the electrolytic solution at a depth of 2 cm. The electrodes were connected to the positive and negative terminals of a DC power supply. The electrosynthesis was performed galvanostatically at 0.5 to 2.5 hours and voltages were varied from 8 to 12 V under constant stirring at room temperature. The resulted suspension was aged at 48 hrs, filtered, dried directly in an oven at 150°C for 2 hrs, washed 2 times, and dried again 60 °C for 6 hrs. The particle product has been used to lithium-ion battery as anode. Synthesis of TiO{sub 2} particle by electrochemical method at 10 V for 1 to 2.5 hrs resulted anatase and rutile phase.

  17. One-pot hydrothermal synthesis of Nitrogen-doped graphene as high-performance anode materials for lithium ion batteries.

    Science.gov (United States)

    Xing, Zheng; Ju, Zhicheng; Zhao, Yulong; Wan, Jialu; Zhu, Yabo; Qiang, Yinghuai; Qian, Yitai

    2016-01-01

    Nitrogen-doped (N-doped) graphene has been prepared by a simple one-step hydrothermal approach using hexamethylenetetramine (HMTA) as single carbon and nitrogen source. In this hydrothermal process, HMTA pyrolyzes at high temperature and the N-doped graphene subsequently self-assembles on the surface of MgO particles (formed by the Mg powder reacting with H2O) during which graphene synthesis and nitrogen doping are simultaneously achieved. The as-synthesized graphene with incorporation of nitrogen groups possesses unique structure including thin layer thickness, high surface area, mesopores and vacancies. These structural features and their synergistic effects could not only improve ions and electrons transportation with nanometer-scale diffusion distances but also promote the penetration of electrolyte. The N-doped graphene exhibits high reversible capacity, superior rate capability as well as long-term cycling stability, which demonstrate that the N-doped graphene with great potential to be an efficient electrode material. The experimental results provide a new hydrothermal route to synthesize N-doped graphene with potential application for advanced energy storage, as well as useful information to design new graphene materials. PMID:27184859

  18. Analysis of the electrochemical performance of MoNi-CeO2 cermet as anode material for solid oxide fuel cell. Part I. H2, CH4 and H2/CH4 mixtures as fuels

    Science.gov (United States)

    Escudero, M. J.; Gómez de Parada, I.; Fuerte, A.; Serrano, J. L.

    2014-05-01

    This paper investigates the catalytic activity and the electrochemical performance of bimetallic formulation combining Mo and Ni with CeO2 (MoNi-Ce) in relation its potential use as anode material for SOFC. The catalytic properties were evaluated for methane partial oxidation as function of temperature and the carbon deposition on the anode surface was analysed by TG-MS. A conversion of 12.8% was reached for partial methane oxidation at 850 °C as well as a high coke resistance. The electrochemical performance was studied in a single cell with La0.58Sr0.4Fe0.8Co0.2O3-δ (LSCF) as cathode, La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM) as electrolyte and MoNi-Ce as anode. A thin buffer layer of La0.4Ce0.6O4-δ (LCD) between anode and electrolyte was used to avoid possible interfacial reactions. The cell was tested in different humidified fuels (H2, CH4 and H2/CH4 mixtures) and static air at 750, 800 and 850 °C. The electrochemical behaviour was evaluated by current-voltage curves, impedance spectroscopy and load demand. Stability tests were also performed in pure CH4 at each studied temperature in order to assess degradation of the electrochemical cell performance. No significant performance degradation was detected in all studied fuels even pure methane, which suggests that MoNi-Ce is a suitable anode material for direct methane SOFC.

  19. Research status and development trend on Si-based anode materials of lithium ion batteries%锂离子电池硅基负极材料研究现状与发展趋势

    Institute of Scientific and Technical Information of China (English)

    张培新; 汪静伟; 黄亮; 张冬云

    2014-01-01

    硅基负极材料因具有高电化学容量是一种极具发展前景的锂离子电池负极材料。评述单质硅、硅-金属合金、硅-碳复合材料以及其他硅基复合材料作为锂离子二次电池负极材料的最新研究成果,分析锂离子电池硅负极材料存在问题,探讨硅基负极材料的合成、制备工艺以及未来硅基材料的研究方向和应用前景。分析结果表明,通过硅的纳米化、无定形化、合金化及复合化等技术手段,实现硅基负极材料同时兼备高容量、长寿命、高库伦效率和倍率性能,是未来的主要发展方向。%The silicon-based anode materials are of great importance for lithium ion batteries ( LIBs) because of their high capacity. This paper reviews the latest research achievements of the silicon, silicon-metal alloys, silicon-carbon composites and other composite materials as anodes materials and discusses their research and application prospects. It also analyzes the existing problems of pure silicon anodes and focuses mainly on the novel silicon based anode materials. Regarding future research and application, the predominant direction will be to promote both cycle performance and electrochemical performance through the comprehensive application of nanocrystallization, amor-phization, alloying and compounding of silicon-based materials.

  20. Advances in aluminum anodizing

    Science.gov (United States)

    Dale, K. H.

    1969-01-01

    White anodize is applied to aluminum alloy surfaces by specific surface preparation, anodizing, pigmentation, and sealing techniques. The development techniques resulted in alloys, which are used in space vehicles, with good reflectance values and excellent corrosive resistance.

  1. Nitrogen-doped carbon/graphene hybrid anode material for sodium-ion batteries with excellent rate capability

    Science.gov (United States)

    Liu, Huan; Jia, Mengqiu; Cao, Bin; Chen, Renjie; Lv, Xinying; Tang, Renjie; Wu, Feng; Xu, Bin

    2016-07-01

    Nitrogen-doped carbon/graphene (NCG) hybrid materials were prepared by an in-situ polymerization and followed pyrolysis for sodium-ion batteries. The NCG has a large interlayer distance (0.360 nm) and a high nitrogen content of 7.54 at%, resulting in a high reversible sodium storage capacity of 336 mAh g-1 at 30 mA g-1. The NCG shows a sandwich-like structure, i.e. nitrogen-doped carbon nanosheets closely coated on both sides of graphene. The carbon nanosheets shorten the ion diffusion distance, while the sandwiched graphene with high electronic conductivity guarantees fast electron transport, making the NCG exhibit excellent rate capability (94 mAh g-1 at 5 A g-1). It also exhibits good cycle stability with a capacity retention of 89% after 200 cycles at 50 mA g-1.

  2. Characterization and electrochemical properties of Li2MoO4 modified Li4Ti5O12/C anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Li2MoO4 modified Li4Ti5O12/C was prepared by a rheological phase reaction method. • Li2MoO4/C layer is coated on the surface of nanoparticles with partial Mo6+ doping. • The synergistic strategy enhances the electrochemical properties of LTO notably. -- Abstract: Li2MoO4 modified Li4Ti5O12/C anode material has been synthesized by a ball-milling assisted rheological phase reaction method. The structures, morphologies and electrochemical properties of the as-prepared materials have been analyzed by different physical and electrochemical methods. The results show that the amorphous carbon is successfully coated on the surface of Li4Ti5O12 nanoparticles with partial doping of Mo6+ into the Li4Ti5O12 structure. Electrochemical results indicate that Li2MoO4 modified Li4Ti5O12/C samples deliver improved rate capability and decreased charge transfer resistance. Among the investigated samples, the one with 5 wt% Li2MoO4 sample exhibits the optimal electrochemical properties and it shows a large capacity of 167.5 mAh g−1 at 1C rate, which is close to its theoretical capacity. Even at 10C, its charge capacity is up to 137.5 mAh g−1 with a high capacity retention of 92.5% after 200 cycles. The excellent electrochemical properties should be attributed to the improvement of electrochemical kinetics by the synergistic employment of reducing particle size, partial Mo6+ doping and Li2MoO4/C modification

  3. Masking of aluminum surface against anodizing

    Science.gov (United States)

    Crawford, G. B.; Thompson, R. E.

    1969-01-01

    Masking material and a thickening agent preserve limited unanodized areas when aluminum surfaces are anodized with chromic acid. For protection of large areas it combines well with a certain self-adhesive plastic tape.

  4. Scalable preparation of porous micron-SnO2/C composites as high performance anode material for lithium ion battery

    Science.gov (United States)

    Wang, Ming-Shan; Lei, Ming; Wang, Zhi-Qiang; Zhao, Xing; Xu, Jun; Yang, Wei; Huang, Yun; Li, Xing

    2016-03-01

    Nano tin dioxide-carbon (SnO2/C) composites prepared by various carbon materials, such as carbon nanotubes, porous carbon, and graphene, have attracted extensive attention in wide fields. However, undesirable concerns of nanoparticles, including in higher surface area, low tap density, and self-agglomeration, greatly restricted their large-scale practical applications. In this study, novel porous micron-SnO2/C (p-SnO2/C) composites are scalable prepared by a simple hydrothermal approach using glucose as a carbon source and Pluronic F127 as a pore forming agent/soft template. The SnO2 nanoparticles were homogeneously dispersed in micron carbon spheres by assembly with F127/glucose. The continuous three-dimensional porous carbon networks have effectively provided strain relaxation for SnO2 volume expansion/shrinkage during lithium insertion/extraction. In addition, the carbon matrix could largely minimize the direct exposure of SnO2 to the electrolyte, thus ensure formation of stable solid electrolyte interface films. Moreover, the porous structure could also create efficient channels for the fast transport of lithium ions. As a consequence, the p-SnO2/C composites exhibit stable cycle performance, such as a high capacity retention of over 96% for 100 cycles at a current density of 200 mA g-1 and a long cycle life up to 800 times at a higher current density of 1000 mA g-1.

  5. Hierarchical Co3O4 Nanoparticles Embedded in a Carbon Matrix for Lithium-Ion Battery Anode Materials

    International Nuclear Information System (INIS)

    Highlights: • Co3O4 nanocrystals with size of 20 nm homogeneously embedded in the carbon matrix are successfully synthesized. • Cycle exceeds 400 times in half cells at a 5 C (5 Ag−1) rate while retaining about 1000 mAhg−1 reversible capacities. • Large rates up to 10 C for are achieved with high energy density. • Such Co3O4 exhibits excellent high-rate capability and cycling stability. - Abstract: A Co3O4-C nanocomposite has been synthesized by a one-step hydrothermal method free of any template with an annealing process. The composite exhibits a flower-like, hollow, and porous skeleton with a large specific surface area of 272.3 m2g−1. The scanning electron microscope (SEM) and transmission electron microscope (TEM) images reveal the hybrid nanostructure comprises ring-like Co3O4 nanocrystals of 20 nm in diameter homogeneously embedded in the carbon matrix. Such integrated electrodes exhibit an ultrahigh specific capacity and excellent cycling stability even at a high charge/discharge current density. Cycle exceeds 400 times in half cells at a 5 C (5 Ag−1) rate while retaining about 1000 mAhg−1 reversible capacities (where a 1 C rate represents a one-hour complete charge or discharge). This study not only provides a simple synthesis method for lithium ion batteries, but also helps in designing novel and high performance electrode materials

  6. Octahedral Tin Dioxide Nanocrystals Anchored on Vertically Aligned Carbon Aerogels as High Capacity Anode Materials for Lithium-Ion Batteries

    Science.gov (United States)

    Liu, Mingkai; Liu, Yuqing; Zhang, Yuting; Li, Yiliao; Zhang, Peng; Yan, Yan; Liu, Tianxi

    2016-01-01

    A novel binder-free graphene - carbon nanotubes - SnO2 (GCNT-SnO2) aerogel with vertically aligned pores was prepared via a simple and efficient directional freezing method. SnO2 octahedrons exposed of {221} high energy facets were uniformly distributed and tightly anchored on multidimensional graphene/carbon nanotube (GCNT) composites. Vertically aligned pores can effectively prevent the emersion of “closed” pores which cannot load the active SnO2 nanoparticles, further ensure quick immersion of electrolyte throughout the aerogel, and can largely shorten the transport distance between lithium ions and active sites of SnO2. Especially, excellent electrical conductivity of GCNT-SnO2 aerogel was achieved as a result of good interconnected networks of graphene and CNTs. Furthermore, meso- and macroporous structures with large surface area created by the vertically aligned pores can provide great benefit to the favorable transport kinetics for both lithium ion and electrons and afford sufficient space for volume expansion of SnO2. Due to the well-designed architecture of GCNT-SnO2 aerogel, a high specific capacity of 1190 mAh/g with good long-term cycling stability up to 1000 times was achieved. This work provides a promising strategy for preparing free-standing and binder-free active electrode materials with high performance for lithium ion batteries and other energy storage devices. PMID:27510357

  7. Octahedral Tin Dioxide Nanocrystals Anchored on Vertically Aligned Carbon Aerogels as High Capacity Anode Materials for Lithium-Ion Batteries.

    Science.gov (United States)

    Liu, Mingkai; Liu, Yuqing; Zhang, Yuting; Li, Yiliao; Zhang, Peng; Yan, Yan; Liu, Tianxi

    2016-01-01

    A novel binder-free graphene - carbon nanotubes - SnO2 (GCNT-SnO2) aerogel with vertically aligned pores was prepared via a simple and efficient directional freezing method. SnO2 octahedrons exposed of {221} high energy facets were uniformly distributed and tightly anchored on multidimensional graphene/carbon nanotube (GCNT) composites. Vertically aligned pores can effectively prevent the emersion of "closed" pores which cannot load the active SnO2 nanoparticles, further ensure quick immersion of electrolyte throughout the aerogel, and can largely shorten the transport distance between lithium ions and active sites of SnO2. Especially, excellent electrical conductivity of GCNT-SnO2 aerogel was achieved as a result of good interconnected networks of graphene and CNTs. Furthermore, meso- and macroporous structures with large surface area created by the vertically aligned pores can provide great benefit to the favorable transport kinetics for both lithium ion and electrons and afford sufficient space for volume expansion of SnO2. Due to the well-designed architecture of GCNT-SnO2 aerogel, a high specific capacity of 1190 mAh/g with good long-term cycling stability up to 1000 times was achieved. This work provides a promising strategy for preparing free-standing and binder-free active electrode materials with high performance for lithium ion batteries and other energy storage devices. PMID:27510357

  8. Preparation and characterization of flake graphite/silicon/carbon spherical composite as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: ► Flake graphite/silicon/carbon composite is synthesized via spray drying. ► Flake graphite of ∼0.5 μm and glucose are used to prepare the composite. ► The as-prepared composite shows spherical and porous appearance. ► The composite shows nearly the same cycleability as commercial graphite in 20 cycles. ► The composite shows a reversible capacity of 552 mAh/g at the 20th cycle. - Abstract: Using nano-Si, glucose and flake graphite of ∼0.5 μm as raw materials, flake graphite/silicon/carbon composite is successfully synthesized via spray drying and subsequent pyrolysis. The samples are characterized by XRD, SEM, TEM and electrochemical measurements. The composite is composed of flake graphite, nano-Si and amorphous glucose-pyrolyzed carbon and presents good spherical appearance. Some micron pores arising from the decomposition of glucose exist on the surface of the composite particles. The composite has a high reversible capacity of 602.7 mAh/g with an initial coulombic efficiency of 69.71%, and shows nearly the same cycleability as the commercial graphite in 20 cycles. Both the glucose-pyrolyzed carbon and the micron pores play important roles in improving the cycleability of the composite. The flake graphite/silicon/carbon composite electrode is a potential alternative to graphite for high energy-density lithium ion batteries.

  9. An Insoluble Titanium-Lead Anode for Sulfate Electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Ferdman, Alla

    2005-05-11

    The project is devoted to the development of novel insoluble anodes for copper electrowinning and electrolytic manganese dioxide (EMD) production. The anodes are made of titanium-lead composite material produced by techniques of powder metallurgy, compaction of titanium powder, sintering and subsequent lead infiltration. The titanium-lead anode combines beneficial electrochemical behavior of a lead anode with high mechanical properties and corrosion resistance of a titanium anode. In the titanium-lead anode, the titanium stabilizes the lead, preventing it from spalling, and the lead sheathes the titanium, protecting it from passivation. Interconnections between manufacturing process, structure, composition and properties of the titanium-lead composite material were investigated. The material containing 20-30 vol.% of lead had optimal combination of mechanical and electrochemical properties. Optimal process parameters to manufacture the anodes were identified. Prototypes having optimized composition and structure were produced for testing in operating conditions of copper electrowinning and EMD production. Bench-scale, mini-pilot scale and pilot scale tests were performed. The test anodes were of both a plate design and a flow-through cylindrical design. The cylindrical anodes were composed of cylinders containing titanium inner rods and fitting over titanium-lead bushings. The cylindrical design allows the electrolyte to flow through the anode, which enhances diffusion of the electrolyte reactants. The cylindrical anodes demonstrate higher mass transport capabilities and increased electrical efficiency compared to the plate anodes. Copper electrowinning represents the primary target market for the titanium-lead anode. A full-size cylindrical anode performance in copper electrowinning conditions was monitored over a year. The test anode to cathode voltage was stable in the 1.8 to 2.0 volt range. Copper cathode morphology was very smooth and uniform. There was no

  10. Effects of the rate of anodic oxidation of the cadmium electrode and the type of separator material on the concentration of cadmium hydroxy complexes in the interelectrode space of alkali batteries

    International Nuclear Information System (INIS)

    Concentration of cadmium hydroxy complexes in the interelectrode space of the alkaline battery mock-up behind separator materials during the anodic process on the cadmium electrode have been defined by the chronoamperometry method on the solid microelectrode. It has been found, that the supersaturation of cadmium hydroxy complexes in the interelectrode space has sharply decreased in comparison with separators of the regular structure under using of inorganic separators based on asbestos

  11. Research Advances in Silicon-Based Anode Materials of High Capacity Lithium Ion Battery%高容量型锂离子电池硅基负极材料的研究

    Institute of Scientific and Technical Information of China (English)

    胡社军; 张苗; 侯贤华; 王洁; 李敏; 刘祥

    2013-01-01

    Due to its high capacity , silicon based anode materials have been widely studied in recent years .How-ever,the commercialization of silicon-based materials as the anode of lithium-ion batteries( LIBs) has been hindered by the huge volume change , poor cycle life and low initial coulombic efficiency during the charge /discharge process .This article analyses the insertion/interinsertion lithium ion principle of silicon anodes , reviews the change of the crystal structure and the surface/interface of Si-based material during the intercalation/deintercalation of lith-ium, and the methods for improving the electrochemical performance .The prospects of silicon-based materials as the anode of LIBs are also discussed .%硅基负极材料由于具有高容量而被广泛研究,该材料在充/放电过程中巨大的体积变化、低的循环寿命和初始库仑效率阻碍了其商业化应用。在作者多年从事硅基负极材料的研究基础上,分析了硅基负极材料的工作原理,回顾了Si负极在脱/嵌锂过程中的晶体结构、表面/界面的变化以及提高其电化学性能的方法,讨论了锂离子电池硅基负极材料的前景。

  12. Si clusters/defective graphene composites as Li-ion batteries anode materials: A density functional study

    International Nuclear Information System (INIS)

    Highlights: • We study the interaction between Si clusters with pristine and defective graphene. • We find that the binding strength of Si clusters on graphene can be enhanced to different degrees after introducing various defects. • It is found that both graphene and Si cluster in the Si/graphene composites can preserve their Li uptake ability. - Abstract: Recently, the Si/graphene hybrid composites have attracted considerable attention due to their potential application for Li-ion batteries. How to effectively anchor Si clusters to graphene substrates to ensure their stability is an important factor to determine their performance for Li-ion batteries. In the present work, we have performed comprehensive density functional theory (DFT) calculations to investigate the geometric structures, stability, and electronic properties of the deposited Si clusters on defective graphenes as well as their potential applications for Li-ion batteries. The results indicate that the interfacial bonding between these Si clusters with the pristine graphene is quietly weak with a small adsorption energy (<−0.21 eV). Due to the presence of vacancy site, the binding strength of Si clusters on defective graphene is much stronger than that of pristine one, accompanying with a certain amount of charge transfer from Si clusters to graphene substrates. Moreover, the ability of Si/graphene hybrids for Li uptake is studied by calculating the adsorption of Li atoms. We find that both graphenes and Si clusters in the Si/graphene composites preserve their Li uptake ability, indicating that graphenes not only server as buffer materials for accommodating the expansion of Si cluster, but also provide additional intercalation sites for Li

  13. Si clusters/defective graphene composites as Li-ion batteries anode materials: A density functional study

    Energy Technology Data Exchange (ETDEWEB)

    Li, Meng; Liu, Yue-Jie; Zhao, Jing-xiang, E-mail: zhaojingxiang@hrbnu.edu.cn; Wang, Xiao-guang, E-mail: hsdwsg@163.com

    2015-08-01

    Highlights: • We study the interaction between Si clusters with pristine and defective graphene. • We find that the binding strength of Si clusters on graphene can be enhanced to different degrees after introducing various defects. • It is found that both graphene and Si cluster in the Si/graphene composites can preserve their Li uptake ability. - Abstract: Recently, the Si/graphene hybrid composites have attracted considerable attention due to their potential application for Li-ion batteries. How to effectively anchor Si clusters to graphene substrates to ensure their stability is an important factor to determine their performance for Li-ion batteries. In the present work, we have performed comprehensive density functional theory (DFT) calculations to investigate the geometric structures, stability, and electronic properties of the deposited Si clusters on defective graphenes as well as their potential applications for Li-ion batteries. The results indicate that the interfacial bonding between these Si clusters with the pristine graphene is quietly weak with a small adsorption energy (<−0.21 eV). Due to the presence of vacancy site, the binding strength of Si clusters on defective graphene is much stronger than that of pristine one, accompanying with a certain amount of charge transfer from Si clusters to graphene substrates. Moreover, the ability of Si/graphene hybrids for Li uptake is studied by calculating the adsorption of Li atoms. We find that both graphenes and Si clusters in the Si/graphene composites preserve their Li uptake ability, indicating that graphenes not only server as buffer materials for accommodating the expansion of Si cluster, but also provide additional intercalation sites for Li.

  14. Fabrication of anodic aluminum oxide with incorporated chromate ions

    Science.gov (United States)

    Stępniowski, Wojciech J.; Norek, Małgorzata; Michalska-Domańska, Marta; Bombalska, Aneta; Nowak-Stępniowska, Agata; Kwaśny, Mirosław; Bojar, Zbigniew

    2012-10-01

    The anodization of aluminum in 0.3 M chromic acid is studied. The influence of operating conditions (like anodizing voltage and electrolyte's temperature) on the nanoporous anodic aluminum oxide geometry (including pore diameter, interpore distance, the oxide layer thickness and pores density) is thoroughly investigated. The results revealed typical correlations of the anodic alumina nanopore geometry with operating conditions, such as linear increase of pore diameter and interpore distance with anodizing voltage. The anodic aluminum oxide is characterized by a low pores arrangement, as determined by Fast Fourier transforms analyses of the FE-SEM images, which translates into a high concentration of oxygen vacancies. Moreover, an optimal experimental condition where chromate ions are being successfully incorporated into the anodic alumina walls, have been determined: the higher oxide growth rate the more chromate ions are being trapped. The trapped chromate ions and a high concentration of oxygen vacancies make the anodic aluminum oxide a promising luminescent material.

  15. Effects of TiO{sub 2} crystal structure on the performance of Li{sub 4}Ti{sub 5}O{sub 12} anode material

    Energy Technology Data Exchange (ETDEWEB)

    Ning Feng [Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); He Yanbing [Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Li Baohua, E-mail: libh@mail.sz.tsinghua.edu.cn [Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Du Hongda [Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Zhai Dengyun [Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Kang Feiyu, E-mail: fykang@mail.tsinghua.edu.cn [Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2012-02-05

    Highlights: Black-Right-Pointing-Pointer The reactivity of TiO{sub 2} with Li{sub 2}CO{sub 3} gradually decreases as the TiO{sub 2} crystal structure changes. Black-Right-Pointing-Pointer The specific capacity of Li{sub 4}Ti{sub 5}O{sub 12} decreases obviously with the TiO{sub 2} crystal structure changing. Black-Right-Pointing-Pointer The TiO{sub 2} crystal structure has not large effects on the cycling performance of Li{sub 4}Ti{sub 5}O{sub 12} material. Black-Right-Pointing-Pointer The reaction of TiO{sub 2} with Li{sub 2}CO{sub 3} is an exothermic behavior. - Abstract: Li{sub 4}Ti{sub 5}O{sub 12} anode material is synthesized using TiO{sub 2} with different crystal structure as titanium source by solid-state method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical test methods are applied to characterize the effects of TiO{sub 2} crystal structure on the structure, morphology and electrochemical performance of Li{sub 4}Ti{sub 5}O{sub 12}. Results show that the reaction of TiO{sub 2} with Li{sub 2}CO{sub 3} is an exothermic behavior. The reactivity of TiO{sub 2} with Li{sub 2}CO{sub 3} gradually decreases and the particles size of Li{sub 4}Ti{sub 5}O{sub 12} increases with the TiO{sub 2} crystal structure changing from amorphous to rutile. The TiO{sub 2} crystal structure has a slight influence on the reversibility of Li{sub 4}Ti{sub 5}O{sub 12}, while the specific capacities of Li{sub 4}Ti{sub 5}O{sub 12} at different current densities decreases obviously with the TiO{sub 2} crystal structure changing from amorphous to rutile and the sample using amorphous TiO{sub 2} as titanium sources shows highest specific capacity. The capacity retentions of all Li{sub 4}Ti{sub 5}O{sub 12} samples are above 97% after 50 cycles and these materials show good cycle performance. The TiO{sub 2} crystal structure has not large effects on the cycling performance of Li{sub 4}Ti{sub 5}O{sub 12} material.

  16. 锂离子电池纳米级硅负极的研究进展%Research progress of nano-silicon based anode materials for lithium ion batteries

    Institute of Scientific and Technical Information of China (English)

    周向阳; 唐晶晶; 杨娟; 王松灿; 谢静

    2012-01-01

    硅基材料是新一代高容量锂离子电池负极材料的典型代表,近年来已成为理论和应用研究的热点.纳米硅基负极材料因具有独特的表面效应和尺寸效应等优点,可大大改善硅作为负极时所存在的循环性能,有望解决限制硅负极成为替代商业化石墨负极的瓶颈问题.介绍了近年来纳米级硅负极作为锂离子电池负极材料的最新研究进展,包括纳米硅颗粒、硅纳米线、硅纳米管及纳米硅薄膜,分析了纳米硅作为锂离子电池负极材料存在的问题,总结了纳米级硅作为锂离子电池负极较为可行的研究方法,展望了纳米硅作为高能量密度锂离子电池负极材料的研究前景.%Silicon-based materials have been extensively studied as the typical representation of high capacity anode materials in lithium-ion batteries. Nano-silicon based anodes have been investigated as possible substitute for the commercial graphite or carbon due to their unique surface effect and size effect. The nano-silicon based anode materials in recent years were reviewed, including nano-silicon powder, silicon nanowires, silicon nanotubes and nanosized silicon thin film. The prospects for high energy density lithium ion batteries anode materials were also discussed. The feasible research methods for the nanoscale silicon as anode materials were summarized. The new material for lithium-ion batteries would be promising if some problems can be solved.

  17. Low voltage aluminium anodes. Optimization of the insert-anode bond

    Energy Technology Data Exchange (ETDEWEB)

    Le Guyader, Herve; Debout, Valerie; Grolleau, Anne-Marie [DCN Cherbourg, Departement 2EI, Place Bruat, BP 440, 50104 Cherbourg-Octeville (France); Pautasso, Jean-Pierre [DGA/CTA 16 bis, avenue Prieur de la Cote D' Or, 94 114 Arcueil Cedex (France)

    2004-07-01

    Zinc or Al/Zn/In sacrificial anodes are widely used to protect submerged marine structures from corrosion. Their Open Circuit Potential range from - 1 V vs. Ag/AgCl for Zn anodes to -1.1 V vs. Ag/AgCl for Al/Zn/In. These potentials are sufficiently electronegative as to reduce the threshold for stress corrosion cracking and/or hydrogen embrittlement, KISCC, especially in the presence of high strength alloys. In the 90's, an extensive research programme was initiated by DGA/DCN to implement a new low voltage material. Laboratory and full scale marine tests performed on industrial castings, as previously reported, led to the development of a new patented Al- 0.1%Ga alloy having a working potential of - 0.80 to - 0.83 V vs. Ag/AgCl. This alloy was also evaluated at full scale at the Naval Research Laboratory anode qualification site in Key West, Fl, and gave satisfactory results. Around 500 cylindrical AlGa anodes were then installed on a submerged marine structure replacing the classical zinc anode. A first inspection, carried out after a few months of service, showed that some of the anodes had not operated as expected, which led to further investigations. The examinations performed indicated that the problem was due to a bad metallurgical compatibility between the insert and the sacrificial materials inducing a poor bond between the anode and the plain rod insert. Progressive loss of contact between the anode and the structure to be protected was then induced by penetration of sea water and corrosion at the anode-insert interface. This phenomenon was aggravated by seawater pressure. Additional studies were therefore launched with two aims: (1) find temporary remedies for the anodes already installed on the structure; (2) correct the anode original design and/or manufacturing process to achieve the maximum performance on new anodes lots. This paper describes the various solutions investigated to improve the insert-anode bond: design of the anode, rugosity and

  18. Enhanced electrochemical performance of Li4Ti5O12 as anode material for lithium-ion batteries with different carbons as support

    International Nuclear Information System (INIS)

    Nano-Li4Ti5O12/carbon composites with various structures are designed using tetrabutyl titanate as a precursor via a facile in situ liquid deposition method in the presence of three different carbons (multiwalled carbon nanotubes, spherical conductive carbon black super-P and ordered macroporous carbon). The nano-Li4Ti5O12/carbon composites with various morphologies are formed depending on the carbon matrixes used. The Li4Ti5O12 particles obtained are approximately 100 nm in size and homogeneously dispersed in different carbon matrixes. It is found that the structures of the carbon matrixes have a close relation to the discharge capacities of the composites. At the discharge current density of 875 mA g−1, the discharge capacities of nano-Li4Ti5O12/carbon composites with 10 wt% carbon are 138.6, 120.8 and 120.9 mAh g−1 for carbon nanotubes, super-P and porous carbon as the carbon supports, respectively. The nano-Li4Ti5O12/carbon using carbon nanotubes as support exhibits superior performance with large reversible capacity, excellent cycle stability and good rate capability. Capacity retention of 99% can be maintained after 100 cycles, suggesting its promising potential as anode materials. - Highlights: • Li4Ti5O12/carbon nanocomposites are designed using different carbons as supports. • Li4Ti5O12 particles formed on carbon matrix are fine and homogeneous. • Aggregation and growth of Li4Ti5O12 particles are inhibited. • The Li4Ti5O12/carbon nanocomposites exhibit superior electrochemical performance

  19. High rate capability and long cycle stability of TiO{sub 2−δ}–La composite nanotubes as anode material for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jiwei; Zhang, Jingwei, E-mail: jwzhang@henu.edu.cn; Ren, Huanhuan; Yu, Laigui; Wu, Zhishen; Zhang, Zhijun, E-mail: zhangzhijun@henu.edu.cn

    2014-10-01

    Highlights: • TiO{sub 2−δ}–La composite nanotubes were synthesized. • Nanotubular morphology destruction is alleviated during the heat-treatment process. • Mixed Ti{sup 4+}/Ti{sup 3+} valence is generated. • As a result, the composite shows excellent rate capability and cyclability. - Abstract: TiO{sub 2−δ}–La composite nanotubes are prepared by heating the ethanol solution of La(NO{sub 3}){sub 3}⋅6H{sub 2}O which is introduced into nanotube titanium acid at pre-set temperature. The effect of La dosage on the microstructure and electrochemical properties of as-fabricated TiO{sub 2−δ}–La composite nanotubes is investigated. Results indicate that La{sup 3+} can be trapped in the internal/external surfaces and the interlayer space of nanotubes. All of these help to retain the nanotubular morphology and layered structure during the dehydration process. Ti{sup 3+} defects generated by the dehydration of nanotube titanium acid can be stabilized by the formed Ti–O–La bond. So, as-fabricated TiO{sub 2−δ}–La composite nanotubes samples exhibit markedly improved electrochemical properties than pristine TiO{sub 2}. Particularly, the electrode made of TiO{sub 2−δ}–La composite nanotubes containing 5% La element (mass fraction) has a high capacity of 142 mA h g{sup −1} at a charge/discharge rate of 20 C rate and a capacity retention of 87% after 1000 cycles at 10 C, showing superior electrochemical performance and great potential as an anode material for high-rate lithium-ion batteries.

  20. One-step synthesis of SnO2@rGO–carbon particle framework nanoarchitectures as anode materials for tunable lithium storage properties

    International Nuclear Information System (INIS)

    Highlights: • SnO2@rGO–carbon particles framework nanoarchitecture was prepared by facile coprecipitation. • The SnO2@rGO–carbon particles nanoarchitecture could tune the electrochemical properties. • SnO2@rGO–BP2000 shows the best cycling performance. • The SnO2@rGO–carbon particle guarantees effectively lithium ion/electron conductivity. - Abstract: A series of novel nanoarchitectures of SnO2@rGO–carbon inserted with carbon nanoparticles of BP2000 and KJ600 was successfully prepared by a facile coprecipitation method. TGA, XRD, SEM, TEM and Raman spectrom analysis are carried out and indicate that SnO2 nanoparticles and carbon intermediates are uniformly dispersed on graphene nanosheets at a molecular level, forming the framework nanoarchitectures of SnO2@rGO–carbon particles. SnO2@rGO–BP2000 delivers a discharge capacity of 1284.4 mAhg−1 and 76% retention of the reversible capacities after 60 cycles at an initial current density of 100 mAg−1. SnO2@rGO–BP2000 also showed the best rate performance among three anode materials at both high and low rate. The outstanding performance of the SnO2@rGO–BP2000 is attributed to well-defined morphology with suitable particle size, uniform distribution as well as enough room for the SnO2 volume expansion based on the graphene–carbon particles framework

  1. One-step synthesis of SnO{sub 2}@rGO–carbon particle framework nanoarchitectures as anode materials for tunable lithium storage properties

    Energy Technology Data Exchange (ETDEWEB)

    Bu, Yakun [College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350108 (China); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, YangQiao West Road 155#, Fuzhou 350002 (China); Key Laboratory of Design and Assembly of Functional Nanostructures, Chinese Academy of Sciences, YangQiao West Road 155#, Fuzhou 350002 (China); Huang, Yiyin; Li, Tengfei; Wu, Peng; Wang, Yaobing [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, YangQiao West Road 155#, Fuzhou 350002 (China); Key Laboratory of Design and Assembly of Functional Nanostructures, Chinese Academy of Sciences, YangQiao West Road 155#, Fuzhou 350002 (China); Yao, Jiannian [Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2015-04-25

    Highlights: • SnO{sub 2}@rGO–carbon particles framework nanoarchitecture was prepared by facile coprecipitation. • The SnO{sub 2}@rGO–carbon particles nanoarchitecture could tune the electrochemical properties. • SnO{sub 2}@rGO–BP2000 shows the best cycling performance. • The SnO{sub 2}@rGO–carbon particle guarantees effectively lithium ion/electron conductivity. - Abstract: A series of novel nanoarchitectures of SnO{sub 2}@rGO–carbon inserted with carbon nanoparticles of BP2000 and KJ600 was successfully prepared by a facile coprecipitation method. TGA, XRD, SEM, TEM and Raman spectrom analysis are carried out and indicate that SnO{sub 2} nanoparticles and carbon intermediates are uniformly dispersed on graphene nanosheets at a molecular level, forming the framework nanoarchitectures of SnO{sub 2}@rGO–carbon particles. SnO{sub 2}@rGO–BP2000 delivers a discharge capacity of 1284.4 mAhg{sup −1} and 76% retention of the reversible capacities after 60 cycles at an initial current density of 100 mAg{sup −1}. SnO{sub 2}@rGO–BP2000 also showed the best rate performance among three anode materials at both high and low rate. The outstanding performance of the SnO{sub 2}@rGO–BP2000 is attributed to well-defined morphology with suitable particle size, uniform distribution as well as enough room for the SnO{sub 2} volume expansion based on the graphene–carbon particles framework.

  2. CTAB-assisted sol-gel synthesis of Li4Ti5O12 and its performance as anode material for Li-ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: Discharge capacity versus cycle number of Li4Ti5O12 samples synthesized by (a) CTAB-assisted sol-gel and (b) normal sol-gel method. Highlights: → CTAB-assisted sol-gel route for the synthesis of nano-size Li4Ti5O12. → CTAB directs the microstructure of the gels and helps to control the particle size of Li4Ti5O12. → Li4Ti5O12 exhibits promising cycling performance with initial capacity of 174 mAh g-1 and sustains ∼94% beyond 30 cycles. -- Abstract: A simple CTAB-assisted sol-gel technique for synthesizing nano-sized Li4Ti5O12 with promising electrochemical performance as anode material for lithium ion battery is reported. The structural and morphological properties are investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The electrochemical performance of both samples (with and without CTAB) calcined at 800 oC is evaluated using SwagelokTM cells by galvanostatic charge/discharge cycling at room temperature. The XRD pattern for sample prepared in presence of CTAB and calcined at 800 oC shows high-purity cubic-spinel Li4Ti5O12 phase (JCPDS no. 26-1198). Nanosized-Li4Ti5O12 calcined at 800 oC in presence of CTAB exhibits promising cycling performance with initial discharge capacity of 174 mAh g-1 (∼100% of theoretical capacity) and sustains a capacity value of 164 mAh g-1 beyond 30 cycles. By contrast, the sample prepared in absence of CTAB under identical reaction conditions exhibits initial discharge capacity of 140 mAh g-1 (80% of theoretical capacity) that fades to 110 mAh g-1 after 30 cycles.

  3. High-rate performance of SnS2 nanoplates without carbon-coating as anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Two-dimensional (2D) SnS2 nanoplates were synthesized through a facile hydrothermal method. The influences of reaction conditions such as temperature and pH on the size, crystallinity and the forming process of SnS2 were investigated in detail. At low temperature (160 °C), the SnS2 nanoplates showed poor crystallinity; while at higher temperatures above 200 °C, the crystallinity and thickness of the SnS2 nanoplates tended to increase. In addition, pH had notable impact on the nucleation velocity of SnO2 and the conversion speed from SnO2 to SnS2 in further as well. When used as anode materials in rechargeable lithium ion batteries, the SnS2 nanoplates synthesized at 200 °C and pH = 10.5 (SnS2-200-10.5) showed the best lithium storage capacity, good cycling stability and excellent rate capability. It retained a high reversible capacity of 521 mA h g−1 over 50 cycles at a current of 100 mA g−1, equal to 90.0% of the initial reversible capacity. In addition, the coulombic efficiency increased from 36% in the first cycle to over 97% in the subsequent cycles. Even at high current densities of 1, 2 and 3 A g−1, the electrodes could still delivery as high as 472, 397 and 340 mA h g−1, respectively. The enhanced electrochemical performance of the SnS2-200-10.5 can be attributed to the compact and regular crystal structure with a moderate thickness and crystallinity, which is beneficial for maintaining the stability of the structure and fast ion transport during lithiation/delithiation processes

  4. Synthesis and electrochemical performances of ZnO/MnO2 sea urchin-like sleeve array as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    MnO2 is electrodeposited onto ZnO nanorod array grown on Ni foil, forming a binder-free ZnO/MnO2 composited electrode. XRD, EDS, SEM and TEM are used to analyze the phase and microstructure of this composite. Burr-like MnO2 nanoflakes grows on ZnO nanorod array, the top of the composite is hollow and at the bottom exists ZnO large block core as an internal support, forming ZnO/MnO2 sea urchin-like sleeve array. As anode material for lithium ion batteries, ZnO/MnO2 sleeve array exhibits higher discharge capacity and coulombic efficiency, better rate performance and cycling stability than single ZnO nanorod array or directly electrodepsited MnO2, and the composite effect is very remarkable. After 100 cycles, the discharge capacity of ZnO/MnO2 still reaches 1259 mA h g−1, and coulombic efficiency surpasses 98%, higher than those of ZnO nanorod array (111 mA h g−1) and directly electrodeposited MnO2 (507 mA h g−1). The improvement of the electrochemical performances is due to the unique sea urchin-like sleeve array architecture. MnO2 burr tube shell structure leads to high electrochemical activity while the internal ZnO core support ensures good structure stability. The gradually opening of sea urchin-like sleeve during the cycling further enhances the electrochemical activity of MnO2, stabilizing and increasing electrochemical performances of the ZnO/MnO2 composite

  5. Co-reduction self-assembly of reduced graphene oxide nanosheets coated Cu2O sub-microspheres core-shell composites as lithium ion battery anode materials

    International Nuclear Information System (INIS)

    Cuprous oxide (Cu2O) sub-microspheres @ reduced graphene oxide (rGO) nanosheets core-shell composites with 3D architecture are successfully fabricated by a one-step method through co-reduction of irregular cupric citrate and graphene oxide nanosheets at room temperature. Comparing to the bare Cu2O sub-microspheres and the simple physical mixture of Cu2O and rGO (Cu2O-rGO-M), the Cu2O@rGO electrodes demonstrate dramatically improved capacity, cyclic stability and rate capability as anode materials for lithium ion batteries. At a low current density of 100 mA∙g−1, Cu2O@rGO electrodes deliver a discharge capacity of 534 mAh∙g−1 after 50 cycles, retaining 94% of the initial capacity. Under a higher current density of 1000 mA∙g−1, Cu2O@rGO electrodes exhibit a discharge capacity of 181 mAh∙g−1 after 200 cycles, approximately 4 times larger than that of bare Cu2O sub-microsphere electrodes. The rate capacity retention of Cu2O@rGO electrode is 74% at 200 mA∙g−1 and 38% at 1000 mA∙g−1 relative to 100 mA∙g−1, much better than that for Cu2O-rGO-M (52% and 34%) and bare Cu2O electrodes (13% and 3%,). The enhanced electrochemical performance for Cu2O@rGO might be ascribed to the rGO coating and 3D architecture. The outer coated rGO nanosheets could provide additional 3D conductive networks as well as serve as the buffer layers for accommodating the large volume change of the inner Cu2O sub-microspheres during the charge-discharge cycling

  6. Microwave irradiation synthesis of Co3O4 quantum dots/graphene composite as anode materials for Li-ion battery

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Co3O4 quantum dots/graphene composites are fabricated via microwave irradiation method. • Uniform Co3O4 nanocrystals of 3-8 nm are homogeneously dispersed on graphene nanosheets. • Reversible capacity of the composite retains 1785 mAh g−1 after 90 cycles at 0.1 C. • Co3O4 quantum dots/graphene can tolerate high current cycling and have good retention of capacity. • Enhanced performances could result from quantum and size effects of quantum dots. - Abstract: Co3O4 quantum dots/graphene composites were synthesized by a facile and efficient microwave irradiation method, and they were analyzed using XRD, TEM, HRTEM, and TG. Uniform Co3O4 nanocrystals of about 3-8 nm with a high density are homogeneously dispersed on graphene nanosheets. When used as anode materials for Li-ion batteries, the Co3O4 quantum dots/graphene composites show a significantly enhanced cycling performance (1785 mAh g−1 at 0.1 C after 90 cycles) as well as high rate capability (485 mAh g−1 at 5 C). The reversible capacity is found to be much higher than the theoretical value. The superior performance could be attributed to the interfacial lithium-storage and the quantum and size effects of quantum dots that lead to high activity during the lithiation/delithiation process. In addition, the flexible and conductive graphene nanosheets and well dispersed Co3O4 nanodots as well as the synergetic effect between them also benefit the electrochemical performance by endowing a superior high surface area and shortening the diffusion pathway of lithium ions

  7. High rate capability and long cycle stability of TiO2−δ–La composite nanotubes as anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Highlights: • TiO2−δ–La composite nanotubes were synthesized. • Nanotubular morphology destruction is alleviated during the heat-treatment process. • Mixed Ti4+/Ti3+ valence is generated. • As a result, the composite shows excellent rate capability and cyclability. - Abstract: TiO2−δ–La composite nanotubes are prepared by heating the ethanol solution of La(NO3)3⋅6H2O which is introduced into nanotube titanium acid at pre-set temperature. The effect of La dosage on the microstructure and electrochemical properties of as-fabricated TiO2−δ–La composite nanotubes is investigated. Results indicate that La3+ can be trapped in the internal/external surfaces and the interlayer space of nanotubes. All of these help to retain the nanotubular morphology and layered structure during the dehydration process. Ti3+ defects generated by the dehydration of nanotube titanium acid can be stabilized by the formed Ti–O–La bond. So, as-fabricated TiO2−δ–La composite nanotubes samples exhibit markedly improved electrochemical properties than pristine TiO2. Particularly, the electrode made of TiO2−δ–La composite nanotubes containing 5% La element (mass fraction) has a high capacity of 142 mA h g−1 at a charge/discharge rate of 20 C rate and a capacity retention of 87% after 1000 cycles at 10 C, showing superior electrochemical performance and great potential as an anode material for high-rate lithium-ion batteries

  8. Fabrication of thin silica layer-coated magnetite clusters (nFe3O4/silica) as anode materials for improved Li-ion batteries

    International Nuclear Information System (INIS)

    Thin silica layer-coated magnetite clusters (nFe3O4/silica) were prepared as active anode materials for Li-ion batteries. First, citrate-capped magnetites (C-Fe3O4) were synthesized by the co-precipitation method. Then, 3-aminopropyl trimethoxysilane (APTMS)-linked magnetite clusters (A-nFe3O4) were formed via electrostatic interactions between carboxylate groups of C-Fe3O4 and amine groups of APTMS, and the resulting A-nFe3O4 were heat-treated under N2 flow for 2 h. The calcined A-nFe3O4 at 500 °C exhibited the X-ray diffraction (XRD) patterns mostly attributed to fcc crystalline phases of Fe3O4, whereas the calcined C-Fe3O4 at 500 °C exhibited the XRD patterns attributed to the mixture of fcc crystalline phases of Fe3O4 and hexagonal crystalline phases of α-Fe2O3. The calcined A-nFe3O4 (i.e., nFe3O4/silica) exhibited the improved retention capacity by more than ca. 50% after 50 cycles as compared to the pristine iron oxides. The improved retention capacity of nFe3O4/silica was attributed to the enhanced chemical stability and large surface area of the thin silica layer-coated iron oxide clusters. - Highlights: • Thin silica layer-coated iron oxides (nFe3O4/silica) were facilely prepared. • The nFe3O4/silica exhibited the improved capacity retention by more than 50%. • Inert silica layer minimized the pulverization of iron oxide clusters

  9. Potassium-doped copper oxide nanoparticles synthesized by a solvothermal method as an anode material for high-performance lithium ion secondary battery

    Energy Technology Data Exchange (ETDEWEB)

    Thi, Trang Vu; Rai, Alok Kumar; Gim, Jihyeon; Kim, Jaekook, E-mail: jaekook@chonnam.ac.kr

    2014-06-01

    A simple and efficient approach was developed to synthesize CuO nanoparticles with improved electrochemical performance. Potassium (K{sup +})-doped CuO nanoparticles were synthesized by a simple and cost-effective solvothermal method followed by annealing at 500 °C for 5 h under air atmosphere. For comparison, an undoped CuO sample was also synthesized under the same conditions. X-ray diffraction analysis demonstrates that the K{sup +} ion doping caused no change in the phase structure, and highly crystalline K{sub x}Cu{sub 1−x}O{sub 1−δ} (x = 0.10) powder without any impurity was obtained. As an anode material for a lithium ion battery, the K{sup +}-doped CuO nanoparticle electrode exhibited better capacity retention with a reversible capacity of over 354.6 mA h g{sup −1} for up to 30 cycles at 0.1 C, as well as a high charge capacity of 162.3 mA h g{sup −1} at a high current rate of 3.2 C, in comparison to an undoped CuO electrode (275.9 mA h g{sup −1} at 0.1 C and 68.9 mA h g{sup −1} at 3.2 C). The high rate capability and better cycleability of the doped electrode can be attributed to the influence of the K{sup +} ion nanostructure on the increased electronic conductivity, diffusion efficiency, and kinetic properties of CuO during the lithiation and delithiation process.

  10. Potassium-doped copper oxide nanoparticles synthesized by a solvothermal method as an anode material for high-performance lithium ion secondary battery

    International Nuclear Information System (INIS)

    A simple and efficient approach was developed to synthesize CuO nanoparticles with improved electrochemical performance. Potassium (K+)-doped CuO nanoparticles were synthesized by a simple and cost-effective solvothermal method followed by annealing at 500 °C for 5 h under air atmosphere. For comparison, an undoped CuO sample was also synthesized under the same conditions. X-ray diffraction analysis demonstrates that the K+ ion doping caused no change in the phase structure, and highly crystalline KxCu1−xO1−δ (x = 0.10) powder without any impurity was obtained. As an anode material for a lithium ion battery, the K+-doped CuO nanoparticle electrode exhibited better capacity retention with a reversible capacity of over 354.6 mA h g−1 for up to 30 cycles at 0.1 C, as well as a high charge capacity of 162.3 mA h g−1 at a high current rate of 3.2 C, in comparison to an undoped CuO electrode (275.9 mA h g−1 at 0.1 C and 68.9 mA h g−1 at 3.2 C). The high rate capability and better cycleability of the doped electrode can be attributed to the influence of the K+ ion nanostructure on the increased electronic conductivity, diffusion efficiency, and kinetic properties of CuO during the lithiation and delithiation process.

  11. Enhanced electrochemical performance of oxygen-deficient Li4Ti5O12−x anode material induced by graphene oxide

    International Nuclear Information System (INIS)

    Highlights: • Oxygen-deficient Li4Ti5O12−x was synthesized via solid-state reaction. • The graphene oxide served as a reducing agent during the high temperature reaction. • Both electronic conductivity and Li-ion diffusion coefficient were improved. • Oxygen-deficient Li4Ti5O12−x showed high capacity and excellent cyclic stability. - Abstract: Li4Ti5O12−x anode powder containing oxygen vacancies was synthesized via ball-milling assisted solid-state reaction between LiOH⋅H2O, TiO2 and graphene oxide as reactants. Different from previous reports, graphene oxide played the role of reducing agent in promoting the conversion of Ti(IV) into Ti(III) during the calcination process, the process is accompanied by the formation of oxygen vacancies. This assumption was confirmed by XPS and EPR results. SEM, TEM and Raman shows there is a small amount of residual graphene in the material, but the content of carbon is only 0.026%. The lithium-ion diffusion coefficient of oxygen-deficient Li4Ti5O12−x is calculated to be 1.02 ⋅ 10−12 cm2 s−1, ten times higher than 1.61 ⋅ 10−13 cm2 s−1 for pure Li4Ti5O12. As a result, the as-prepared Li4Ti5O12−x exhibits excellent electrochemical performance, presenting an initial discharge capacity of 172.4 mA h g−1 at 0.5 C with a capacity retention of 96.7% over 100 cycles

  12. One-step solvothermal synthesis of Sn nanoparticles dispersed in ternary manganese-nickel-cobalt carbonate as superior anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Sn with high theoretical specific capacity has suffered from poor cycling stability due to its huge volume changes during charging/discharging processes. In this work, a novel structure of tin nanoparticles well dispersed in ternary manganese-nickel-cobalt carbonate Mn0.54 Ni0.13 Co0.13 (CO3)0.8 (MNCCO3) is synthesized using a facile one-step solvothermal process and demonstrates significantly improved electrochemical performance compared to Sn nanoparticles or bare MNCCO3. Additionally, Sn content can be optimized to maximize the battery performance of the composite. When tested as an anode material in lithium ion batteries, the composite with 10 wt.% Sn nanoparticles dispersed in MNCCO3 matrix (10Sn@MNCCO3) demonstrates the best performance, delivering a high initial charge capacity of 929 mAh/g and retains a specific capacity of 657 mAh/g after 50 cycles and 560 mAh/g after 100 cycles at a specific current of 100 mA/g. The charge capacity of 10Sn@MNCCO3 decreases from a value of 991 mAh/g when cycled at 50 mA/g to 64 mAh/g at 2000 mA/g with the increasing specific current. When the specific current returns from 2000 mA/g to 50 mA/g, 10Sn@MNCCO3 retains a high capacity of 791 mAh/g. The improved electrochemical performance can be ascribed to the synergic effect of both components in the composite, in which ternary carbonate MNCCO3 matrix not only provides high practical capacity, but also effectively accommodates the strain of dramatic volume change during long cycling, meanwhile Sn ensures a good electrical contact of the overall electrode due to its high electronic conductivity

  13. Influence of synthesis conditions on crystal formation and electrochemical properties of TiO2(B) particles as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    TiO2(B) particles as the anode material for lithium-ion batteries were synthesized from three kinds of layered alkali titanates Na2Ti3O7, K2Ti4O9 and Cs2Ti5O11 via H+ ion-exchange followed by heating under several conditions in order to clarify the effect of synthesis conditions on crystal formation and electrochemical properties. Phase formation and crystal structure were analyzed by X-ray diffraction, inductively coupled plasma analysis, and transmission electron microscopy. Reducing of residual alkali cations in the intermediates with ion-exchanging for 2 weeks led to relative high crystallinity which is suitable for smooth migration of lithium ions and has low reactivity with a practical electrolyte. The primitive cell volume of TiO2(B) increased with decreasing heat-treatment temperature of the intermediates. A primitive cell volume of 0.300 nm3 in TiO2(B) structure, which was successfully obtained from the precursor K2Ti4O9 by heating the intermediate at 350 °C for 2 h, causes an expanding of the lithium pathways and storage sites and had a high reversible capacity of 253.1 mA h g−1 close to that of TiO2(B) nanopaticles. This TiO2(B) also showed good cycle performance with the reversible capacity after 200 cycles remaining 95% of the initial capacity, using a practical electrolyte such as LiPF6 in a solution of ethylene carbonate and diethyl carbonate. Consequently, synthesis conditions of H+ ion-exchange time and heat-treatment temperature should be carefully optimized to obtain the large reversible capacity and stable cycle performance of TiO2(B) synthesized from the layered alkali titanates via the H+ ion-exchange process

  14. Highly redox-resistant solid oxide fuel cell anode materials based on La-doped SrTiO3 by catalyst impregnation strategy

    Science.gov (United States)

    Shen, X.; Sasaki, K.

    2016-07-01

    An anode backbone using 40 wt% (ZrO2)0.89(Sc2O3)0.1(CeO2)0.01 (SSZ)-Sr0.9La0.1TiO3 (SLT) cermet was prepared for SSZ electrolyte-supported SOFC single cells. 15 mgcm-2 Ce0.9Gd0.1O2 (GDC) was impregnated to totally cover the SSZ-SLT anode backbone surface acting as a catalyst, and the cell voltage achieved 0.865 V at 200 mAcm-2 using (La0.75Sr0.25)0.98MnO3 (LSM)-SSZ cathode in 3%-humidified hydrogen fuel at 800 °C. Cell performance was substantially improved from 0.865 V to >0.97 V when 0.03 mgcm-2 Pd or Ni was further incorporated as a secondary catalyst into the anode layer. 50 redox cycles were performed to investigate redox stability of this high performance anode. It was found that even after the 50 redox cycle long-term degradation test, cell voltage at 200 mAcm-2 was retained around 0.94 V, higher than the cell performance using the conventional Ni-SSZ cermet anode. The catalytically-active reaction sites at ceria-Pd or ceria-Ni may account for the excellent performance, and the extremely low metal catalyst concentration prevent serious metal aggregation in achieving excellent redox stability.

  15. Nickel and nitrogen co-doped tin dioxide nano-composite as a potential anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Ni and N co-doped SnO2 nano-composite was prepared for the first time. • The co-doped material exhibits the optimal electrochemical performances. • The co-doping increases the grain size, surface area, pore diameter and conductivity. • The accelerated electrode kinetics has been observed, explored and explained. - Abstract: As a promising high capacity anode material for lithium-ion batteries (LIBs), tin dioxide (SnO2) has attracted considerable interest in recent studies. In this paper, nickel-doped tin dioxide (Ni/SnO2), nickel and nitrogen co-doped tin dioxide (Ni-N/SnO2) are prepared to modify the electrochemical properties of as-prepared SnO2. Samples of pure SnO2, Ni/SnO2 and Ni-N/SnO2 are characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM), energy dispersive X-ray analysis (EDAX), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET). It is found that doping and co-doping process does not affect the phase structure of pristine SnO2. However, it obviously influences the morphology, specific surface area, and electrochemical properties of SnO2. Gavalnostatic cycling indicates that the Ni-N/SnO2 nano-composite still remains a high charge capacity of 631 mAh g−1 after 50 cycles. Rate performance evaluation shows that a capacity of 621 mAh g−1 can still be delivered when the current returns back to 0.1 C after 50 cycles at different current densities. Cyclic voltammetry (CV) analysis proves that Ni and N co-doping accelerates the electrode reaction. The results of electrochemical impedance spectroscopy (EIS) demonstrate the low charge-transfer resistance for Ni-N/SnO2, and the following quantitative calculation further confirms the highest electric conductivity and ionic conductivity of Ni-N/SnO2 compared with those of pure SnO2 and Ni/SnO2. This explains the superior capacity retention and rate

  16. 锂离子电池硅基负极改性研究新进展%Research Progress in Silicon Based Anode Materials for Lithium-ion Batteries

    Institute of Scientific and Technical Information of China (English)

    邹幽兰; 杨娟; 周向阳; 唐晶晶; 王松灿; 谢静

    2011-01-01

    Due to its high capacity,silicon based anode materials have been widely studied in recent years. The insertion/interinsertion lithium-ion principle of silicon anode for lithium-ion battery is mainly analyzed, the latest allevi ation methods of cracking and crushing of the silicon are reviewed, and the shortcoming of these methods is also pre sented. With the advantage of high conductivity,high elastic, porous, high stability, polypyrrole compouded with sili con will be the most promising developing direction to improve the cycle stability of silicon-based anode materials in lithium-ion battery.%硅因其具有极高的理论容量而成为现阶段锂离子电池用负极材料研究的热点.介绍了硅基负极材料嵌/脱锂的原理,总结了目前缓解硅开裂与粉碎的一般方法,分析了现行研究中的不足.聚吡咯具有高导电性、高弹性、多孔、高稳定性等优点,为了提高负极材料循环稳定性能,将其与硅结舍得到的Si-PPy复合材料将是最有希望的发展方向.

  17. CNT-enhanced electrochemical property and sodium storage mechanism of Pb(NO3)2 as anode material for Na-ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: Display Omitted -- Highlights: • Pb(NO3)2 is reported at the first time as sodium storage material. • Pb(NO3)2/CNT is prepared by a simple solution method. • Pb(NO3)2/CNT shows enhanced cycling and rate capabilities. • The sodiation mechanism in Pb(NO3)2 is firstly studied by in-situ method. -- Abstract: By using carbon nanotube (CNT), Pb(NO3)2/CNT is fabricated by a solution method and investigated for the first time as probable anode materials for sodium-ion batteries. For comparison, pristine Pb(NO3)2 and Pb(NO3)2/carbon black (CB) are also prepared by the same solution method. Electrochemical results show that Pb(NO3)2/CNT can deliver an initial charge capacity of 285.7 mA h g−1, which is much higher than the pristine Pb(NO3)2 (203.8 mA h g−1) and Pb(NO3)2/CB (252.1 mA h g−1). After 50 cycles, Pb(NO3)2/CNT still maintains a sodium storage capacity of 112.9 mA h g−1. Furthermore, it also shows outstanding rate property compared with other two samples. All the enhanced results can be attributed to the introduction of crosslinked CNTs in the composite, which provide good electronic conductive pathways interconnecting Pb(NO3)2 particles and maintain the whole nano-micro structure upon repeated cycles. The reaction mechanism of Pb(NO3)2 with Na is studied by various in-situ and ex-situ techniques. It can be found that Pb(NO3)2/CNT irreversibly decomposes into Pb, NaNO3, NaN3, and Na2O, and then the resulting metal Pb will further react with Na to form NaxPb alloys during the initial discharge process. In contrast, the charge process is mainly associated with the de-alloying reaction of NaxPb to the formation of Pb

  18. International comparison of Cd content in a quality control material of Navajuelas (Tagelus dombeii) determined by anodic stripping voltammetry, atomic absorption spectrometry and neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Queirolo, F. (Universidad Catolica del Norte, Antofagasta (Chile). Dept. of Chemistry Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Angewandte Physikalische Chemie Universidad de Extremadura, Badajoz (Spain). Dept. of Analytical Chemistry and Electrochemistry); Ostapczuk, P. (Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Angewandte Physikalische Chemie); Valenta, P.; Stegen, S. (Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Angewandte Physikalische Chemie Universidad de Extremadura, Badajoz (Spain). Dept. of Analytical Chemistry and Electrochemistry); Marin, C.; Vinagre, F.; Sanchez, A. (Universidad de Extremadura, Badajoz (Spain). Dept. of Analytical Chemistry and Electrochemistry)

    1991-05-01

    The determination of Cd was performed by neutron activation analysis (NAA), atomic absorption spectrometry (AAS) with flame or in the electrothermal mode and anodic stripping voltammetry in the differential pulse mode (DPASV) and the square wave mode (SWASV). (orig./EF).

  19. 锂离子电池C-Sn-金属复合负极材料的研究进展%Research Progress of C-Sn-alloy Composite Anode Materials for Li-ion Batteries

    Institute of Scientific and Technical Information of China (English)

    王录娥; 任旭梅; 吴峰

    2011-01-01

    The development status of carbon and tin-alloy composite anode materials is introduced. C-Sn com posite materials are classified into three categories, and the electrochemical performance characteristics for every type of composite materials are analysed. The latest progress of C-Sn-alloy composite materials, which have a higher capaci ty and excellent cycle performance is outlined. Therefore, it is a promising anode material for Li-ion batteries in the future.%综述了锂离子电池碳材料与锡基合金复合材料的发展现状,总结了C-Sn二元复合材料的主要种类,并分析了它们作为负极材料的电化学性能特点;同时阐述了C-Sn-金属三元复合材料的发展,这种复合材料结合了碳材料的循环稳定性和合金材料的高比容量的优势,是具有发展前景的新型锂离子电池负极材料.

  20. Lithium Ion Battery Anode Aging Mechanisms

    Directory of Open Access Journals (Sweden)

    Victor Agubra

    2013-03-01

    Full Text Available Degradation mechanisms such as lithium plating, growth of the passivated surface film layer on the electrodes and loss of both recyclable lithium ions and electrode material adversely affect the longevity of the lithium ion battery. The anode electrode is very vulnerable to these degradation mechanisms. In this paper, the most common aging mechanisms occurring at the anode during the operation of the lithium battery, as well as some approaches for minimizing the degradation are reviewed.

  1. The Temperature Stage Which Used At Anode Paste Doughing Process In Green Plant PT Inalum

    OpenAIRE

    Simatupang, Dian Christian

    2011-01-01

    Anode is raw material which used in electrolyse process aluminium smelting, where anode is form mixed of cokes and coal tar pitch, containing carbon element which required in smelting process of alumina to produce aluminium. PT INALUM has been able to produce anode it self, while cathode is still be imported from other countries. Aluminium smelter process which taking place continiously require many of anode, good quality and durable, especially temperature at doughing process of anode paste ...

  2. One-pot solvothermal synthesis of Co1−xMnxC2O4 and their application as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: MnC2O4 exhibited good cycling stability while CoC2O4 showed severe capacity fading phenomenon after 40 cycles. Notably, mixed solid solution having Co0.52Mn0.48C2O4 composition improved the specific reversible discharge capacity to a stable value of ∼1000 mA h g−1 (1 C-rate). - Highlights: • Mixed metal oxalates are synthesized by solvothermal method for the first time. • We control morphologies by varying solvent mixtures and transition metal types. • Li/Co0.52Mn0.48C2O4 is the best capacity and rate-performing cell in this study. • The positive synergistic effect is attributed to optimal Co:Mn mole ratio. • Properties of Co give high capacity values while Mn give good cycling stability. - Abstract: A facile one-pot solvothermal route has been developed to synthesize phase pure MxC2O4⋅2H2O (M = Mn, Co; 0 < x ⩽ 1) microstructures without employing any hard/soft template and their electrochemical performance in lithium-ion batteries has been systematically investigated. Morphology, microstructure and composition of the synthesized materials are characterized by field emission-scanning electron microscopy, X-ray diffraction and energy-dispersive X-ray spectroscopy. Anhydrous micron-sized MnC2O4 and CoC2O4 exhibits specific reversible discharge capacity of ∼800 and 950 mA h g−1 respectively, at 1 C-rate. MnC2O4 exhibited good cycling stability while CoC2O4 showed severe capacity fading phenomenon after 40 cycles, thereafter attaining 400–600 mA h g−1 for all C-rates. Interestingly, mixed solid solution having Co0.52Mn0.48C2O4 composition improved the specific reversible discharge capacity to a stable value of ∼1000 mA h g−1 (1 C-rate), which is one of the highest reported values for such oxalates. The cycling stability of this mixed metal oxalate is remarkably better than its individual constituents at most C-rates. The Mn2+ substitution into CoC2O4 lattice has led to the synergistic modification of the electrochemical

  3. Study of Sr2Mg(Mo0.8Nb0.2)O6-δ as anode material for solid oxide fuel cells using hydrocarbons as fuel

    Science.gov (United States)

    Escudero, M. J.; Gómez de Parada, I.; Fuerte, A.; Daza, L.

    2013-12-01

    Sr2Mg(Mo0.8Nb0.2)O6-δ (SMMNb) was investigated as potential anode material of solid oxide fuel cells (SOFCs) for direct oxidation of methane. The compound was prepared by solid state reaction, followed by annealing under reducing atmosphere of 10% H2/N2 at 900 °C. The structural and morphological properties of fresh and reduced material were characterized by XRD, XPS and SEM. Additionally, catalytic properties towards oxidation of methane, electrical properties in reducing atmosphere as well as thermal and chemical compatibility with common SOFC electrolytes were investigated. These results reveal a double perovskite single phase in the fresh and reduced compound and, after reduction, a change in the niobium valence was observed. SMMNb shows a good activity for methane partial oxidation as well as combined reforming reaction. The material presents a semiconductor behaviour with n-type electronic conduction and an excellent thermal compatibility with SOFC electrolytes such as SDC, GDC and LSGM, based on similarity of values of TEC. However, this material reacts with zirconia-based electrolytes (YSZ and ScSZ). Although, a low electrochemical activity for H2 and CH4 oxidation was found, SMMNb demonstrates high tolerance to carbon deposition when the anode is exposed to methane.

  4. 锂离子电池Si/C复合负极材料研究进展%Research progress of Si/C composite anode materials for lithium ion batteries

    Institute of Scientific and Technical Information of China (English)

    刘传永; 彭瑛; 刘建华

    2013-01-01

    硅和碳复合成锂离子电池复合负极材料,不但解决了碳容量低和硅体积效应大的问题,而且得到综合了碳循环性好和硅容量高特点的负极材料.综述了Si/C复合材料的类型和制备方法,提出了Si/C复合材料未来发展方向.%Silicon and carbon were composited as Si/C composite anode materials for lithium ion batteries,which not only solved the problems that carbon has low capacity of and silicon has big volume affection,but also got the anode materials that integrated the good cycle of carbon with high capacity of silicon.The types and preparation methods of Si/C composite materials were reviewed and the future development direction of Si/C composite materials was raised.

  5. Anodizing Aluminum with Frills.

    Science.gov (United States)

    Doeltz, Anne E.; And Others

    1983-01-01

    "Anodizing Aluminum" (previously reported in this journal) describes a vivid/relevant laboratory experience for general chemistry students explaining the anodizing of aluminum in sulfuric acid and constrasting it to electroplating. Additions to this procedure and the experiment in which they are used are discussed. Reactions involved are also…

  6. Anodized aluminum on LDEF

    Science.gov (United States)

    Golden, Johnny L.

    1993-01-01

    A compilation of reported analyses and results obtained for anodized aluminum flown on the Long Duration Exposure Facility (LDEF) was prepared. Chromic acid, sulfuric acid, and dyed sulfuric acid anodized surfaces were exposed to the space environment. The vast majority of the anodized surface on LDEF was chromic acid anodize because of its selection as a thermal control coating for use on the spacecraft primary structure, trays, tray clamps, and space end thermal covers. Reports indicate that the chromic acid anodize was stable in solar absorptance and thermal emittance, but that contamination effects caused increases in absorptance on surfaces exposed to low atomic oxygen fluences. There were some discrepancies, however, in that some chromic acid anodized specimens exhibited significant increases in absorptance. Sulfuric acid anodized surfaces also appeared stable, although very little surface area was available for evaluation. One type of dyed sulfuric acid anodize was assessed as an optical baffle coating and was observed to have improved infrared absorptance characteristics with exposure on LDEF.

  7. Highly efficient and scalable synthesis of SiOx/C composite with core-shell nanostructure as high-performance anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Highly efficient and scalable colloidal route was employed to synthesize SiOx/C. • Nanosized SiOx/C composite has core-shell structure with a thinner carbon layer. • The SiOx/C composite shows a low x value (O/Si ratio) of ca. 0.88. • High specific capacity, good cycleability and superior rate-capability are achieved. - Abstract: SiOx-based electrodes have shown great potential as lithium ion battery anodes because of their high specific capacity. Nonetheless, synthesis of SiOx-based anodes in an industrially adaptable scale still remains as a great challenge. Herein, we adopt a highly efficient colloidal route to enable scalable and high yield synthesis of core-shell SiOx/C composite. The prepared SiOx/C composite presents a well-distributed nanostructure composing of SiOx nanoparticles coated with a thinner carbon layer. The electrode delivers a stable reversible capacity of ca. 820 mAh g−1 over 100 cycles, and exhibits excellent rate capability. The nano-scale feature of SiOx and the coating carbon layer ensure the excellent electrochemical performance of SiOx/C. The approach is facile, mild and mass-productive, which can be adopted for tunable large-scale production of high-capacity SiOx/C composite anode

  8. Battery, especially for portable devices, has an anode containing silicon

    OpenAIRE

    S. Y. Kan

    2002-01-01

    The anode (2) contains silicon. A battery with a silicon-containing anode is claimed. An Independent claim is also included for a method used to make the battery, comprising the doping of a silicon substrate (1) with charge capacity-increasing material (preferably boron, phosphorous or arsenic), etching the doped substrate layer in order to increase its porosity, and applying a cathode (3) in the form of a lithium oxide compound onto the resulting anode and applying an electrolyte (4) to the ...

  9. Mechanically stable insoluble titanium-lead anodes for sulfate electrolytes

    Directory of Open Access Journals (Sweden)

    Chmiola J.

    2003-01-01

    Full Text Available Different formulations of a new material to be used as an insoluble anode for copper electrowinning, a Ti-Pb composite, were investigated for both mechanical and electrochemical properties. Mechanical and metallographic characteristic tests, as well as short-term deposition tests were used to study the effect of the Ti/Pb ratio on anode performance. Yield strength and elastic modulus, obtained through tensile testing, significantly exceed that of lead. Metallographic procedures were used to assess the uniformity of lead distribution in the material, as well as porosity, which would be decreased below 1 % for most of the compositions under study. Short-term deposition tests were used to determine power consumption, deposit quality current efficiency and weight loss characteristics of the new anode material. The material with only 30 vol.% lead shows approximately the same electrochemical performance as a pure lead anode, but has much higher mechanical properties which prevent warping and extend the lifetime of the anode.

  10. Low-temperature synthesis of LiV{sub 3}O{sub 8} nanosheets as an anode material with high power density for aqueous lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Heli, H., E-mail: hheli7@yahoo.com [Laboratory of Analytical and Physical Electrochemistry, Department of Chemistry, Science and Research Branch, Islamic Azad University, Fars 73715-181 (Iran, Islamic Republic of); Young Researchers Club, Science and Research Branch, Islamic Azad University, Fars 73715-181 (Iran, Islamic Republic of); Yadegari, H.; Jabbari, A. [Department of Chemistry, K. N. Toosi University of Technology, Tehran (Iran, Islamic Republic of)

    2011-04-15

    Research highlights: {yields} Simple and low-temperature route for synthesis of LiV{sub 3}O{sub 8} nanosheets {yields} Enhanced electrochemical redox reaction of the cathode with no phase transition {yields} Applicability of LiV{sub 3}O{sub 8} nanosheets as anode for aqueous lithium battery - Abstract: Nanosheets of lithium vanadium oxide (LiV{sub 3}O{sub 8}) were successfully synthesized by a simple low temperature citrate sol-gel combustion route. Compact nanosheets of the active material were observed by scanning and transmission electron microscopies. X-ray diffraction measurements indicated that as-prepared nanosheets presented pure phase of monoclinic LiV{sub 3}O{sub 8} with p2{sub 1}/m symmetry. Cyclic voltammetry (CV) was employed to investigate the electrochemical behavior of the nanosheets with special emphasis on the application potential as anodic material for aqueous rechargeable lithium batteries. CV studies demonstrated that the LiV{sub 3}O{sub 8} nanosheets represent well-defined reversible peaks. The nanosheets showed a discharge capacity of 63 mAh/g in 1.0 M LiNO{sub 3} solution at a 2C/5 rate.

  11. Nano-sized Li-Fe composite oxide prepared by a self-catalytic reverse atom transfer radical polymerization approach as an anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    A novel Self-catalytic Reverse Atom Transfer Radical Polymerization (RATRP) approach that can provide the radical initiator and the catalyst by the system itself is used to synthesize a nano-sized Li-Fe composite oxide powder in large scale. Its crystalline structure and morphology have been characterized by X-ray diffraction and scanning electron microscopy. The results reveal that the composite is composed of nano-sized LiFeO2 and Fe3O4. Its electrochemical properties are evaluated by charge/discharge measurements. The results show that the Li-Fe composite oxide is an excellent anode material for lithium-ion batteries with good cycling performance (1249 mAh g-1 at 100th cycle) and outstanding rate capability (967 mAh g-1 at 5 C). Such a self-catalytic RATRP approach provides a way to synthesize nano-sized iron oxide-based anode materials industrially with preferable electrochemical performance and can also be applied in other polymer-related area.

  12. SnO2 Nanorods on ZnO Nanofibers: A New Class of Hierarchical Nanostructures Enabled by Electrospinning as Anode Material for High-Performance Lithium-Ion Batteries

    International Nuclear Information System (INIS)

    Highlights: • We have successfully fabricated the novel SnO2/ZnO11HNFs by a simple and controllable strategy. • The present synthetic strategy is controllable and can be further extended to prepare various heterostructure nanocomposites between two metal oxides. • The as-obtained SnO2/ZnO11HNFs exhibits outstanding cycle performance, anodic capacity and rate performance. - Abstract: The ZnO/SnO2 heterogeneous nanofibers (HNFs) have been prepared via an electrospinning method followed by calcination at 500 °C in air. XRD, BET, SEM, TEM and electrochemical measurements were performed to characterize the new material, including structure, morphology and electrochemical properties. The spacing between adjacent SnO2 nanorods on mesoporous ZnO nanofibers is about twice the diameter of each SnO2 nanorod. The SnO2/ZnO11 (molar ratio of Sn: Zn = 1:1) HNFs based electrodes exhibit excellent cycle performance and rate performance, which is attributed to the heterogeneous and mesoporous structure as well as the ultrafine ZnO NPs embedded in the HNFs matrix. Outstanding electrochemical performance as anode material for LIBs together with low cost, facile procedures and high reproducibility make the SnO2/ZnO HNFs have a prospect in the field of energy storage

  13. Electrically conductive anodized aluminum coatings

    Science.gov (United States)

    Alwitt, Robert S. (Inventor); Liu, Yanming (Inventor)

    2001-01-01

    A process for producing anodized aluminum with enhanced electrical conductivity, comprising anodic oxidation of aluminum alloy substrate, electrolytic deposition of a small amount of metal into the pores of the anodized aluminum, and electrolytic anodic deposition of an electrically conductive oxide, including manganese dioxide, into the pores containing the metal deposit; and the product produced by the process.

  14. Is there a difference between the primary stability of anodized and non-anodized mini-screws subjected to repeated cycles of autoclave sterilization?

    OpenAIRE

    Ledingham, Austin D; Şar, Çağla; English, Jeryl D.; Akyalçın, Sercan

    2014-01-01

    Objective: To determine if autoclave sterilization has any deleterious effects on the clinical stability of anodized versus non-anodized mini-screws. Materials and Methods: Thirty anodized and thirty non-anodized Aarhus System mini-screws (American Orthodontics, Sheboygan, WI) were utilized. Each group was divided into three test groups. In each group, mini-screws that were sterilized once using a steam autoclave (Statim 5000, SciCan USA, Canonsburg, Pa) served as the control group (n=10). Th...

  15. Electrochemical properties of ZnO added with Zn-Al-hydrotalcites as anode materials for Zinc/Nickel alkaline secondary batteries

    International Nuclear Information System (INIS)

    Zn-Al layer double hydroxides (LDHs) were prepared through a simple hydrothermal method and proposed as an anode additive for Zn/Ni alkaline secondary batteries. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) of sample LDHs indicates that LDHs was well prepared. The electrochemical properties of the ZnO anodes with different contents of Zn-Al-LDHs were investigated by galvanostatic charge-discharge, cyclic voltammetry (CV) and electrochemical impedance spectroscope (EIS). The structures and morphologies after cycles were also measured by SEM. The results indicate that the presence of Zn-Al-LDHs in the electrode exhibits better electrochemical performance compared with the pure ZnO electrode, such as superior electrochemical cycle stability, better reversibility and higher discharge capacity and utilization ratio. Especially for the electrode added with 24% Zn-Al-LDHs, the discharge capacity hardly declined over 250 cycles, the average utilization ratio could reach 98.5%, and the electrode had no obvious shape change and Zn dendrites after the cycling tests

  16. Highly-Ordered Magnéli Ti4O7 Nanotube Arrays as Effective Anodic Material for Electro-oxidation

    International Nuclear Information System (INIS)

    Pure Magnéli Ti4O7 nanotube arrays (NTA) were successfully fabricated by reducing TiO2 NTA with hydrogen at 850 °C for 30 minutes. The microstructure, composition and electrochemical behavior of the prepared Ti4O7 NTA were characterized by means of X-ray Diffraction, Scanning Electron Microscopy, Transmission Electron Microscopy, X-ray Photoelectron Spectroscopy, Cyclic Voltammetry and Electrochemical Impedance Spectroscopy. The as-prepared Ti4O7 NTA had a highly-ordered tubular structure with high crystallinity, large electrochemical window of water electrolysis (2.4 V vs. Ag/AgCl, pH = 6.0) and low interfacial charge transfer resistance when they were employed as anode for electro-oxidation. Phenol was electro-oxidized on Ti4O7 particles and Ti4O7 NTA with the latter giving 20% more Chemical Oxygen Demand (COD) removal. Pure Ti4O7 NTA also displayed larger degradation coefficient as well as higher COD removal and current efficiency than Boron-doped Diamond and other types of Magnéli NTAs. Cathodic polarization was found to be an effective way of restoring the electrochemical performance of oxidized Ti4O7 NTA as an anode

  17. Energy-savvy solid-state and sonochemical synthesis of lithium sodium titanate as an anode active material for Li-ion batteries

    Science.gov (United States)

    Ghosh, Swatilekha; Kee, Yongho; Okada, Shigeto; Barpanda, Prabeer

    2015-11-01

    Lithium sodium titanate insertion-type anode has been synthesized by classical solid-state (dry) and an alternate solution-assisted (wet) sonochemical synthesis routes. Successful synthesis of the target compound has been realized using simple Na- and Li-hydroxide salts along with titania. In contrast to the previous reports, these energy-savvy synthesis routes can yield the final product by calcination at 650-750 °C for limited duration of 1-10 h. Owing to the restricted calcination duration (dry route for 1-2 h and wet route for 1-5 h), they yield homogeneous nanoscale lithium sodium titanate particles. Sonochemical synthesis reduces the lithium sodium titanate particle size down to 80-100 nm vis-à-vis solid-state method delivering larger (200-500 nm) particles. Independent of the synthetic methods, the end products deliver reversible electrochemical performance with reversible capacity exceeding 80 mAh·g-1 acting as a 1.3 V anode for Li-ion batteries.

  18. A-site deficient La0.2Sr0.7TiO3-δ anode material for proton conducting ethane fuel cell to cogenerate ethylene and electricity

    Science.gov (United States)

    Liu, Subiao; Behnamian, Yashar; Chuang, Karl T.; Liu, Qingxia; Luo, Jing-Li

    2015-12-01

    A site deficient La0.2Sr0.7TiO3-δ (LSTA) and a highly proton conductive electrolyte BaCe0.7Zr0.1Y0.2O3-δ (BCZY) are synthesized by using solid state reaction method. The performance of the electrolyte-supported single cell, comprised of LSTA + Cr2O3 + Cu//BCZY//(La0.60Sr0.40)0.95Co0.20Fe0.80O3-δ (LSCF)+BCZY, is fabricated and investigated. LSTA shows remarkably high electrical performance, with a conductivity as high as 27.78 Scm-1 at 1150 °C in a 10% H2/N2 reducing atmosphere. As a main anode component, it shows good catalytic activity towards the oxidation of ethane, causing the power density to considerably increase from 158.4 mW cm-2 to 320.9 mW cm-2 and the ethane conversion to significantly rise from 12.6% to 30.9%, when the temperature increases from 650 °C to 750 °C. These changes agree well with the polarization resistance which dramatically decreases from 0.346 Ωcm2 to 0.112 Ωcm2. EDX measurement shows that no element diffusion exists (chemical compatibility) between anode (LSTA + Cr2O3+Cu) and electrolyte (BCZY). With these properties, the pure phase LSTA is evaluated as a high electro-catalytic activity anode material for ethane proton conducting solid oxide fuel cell (PC-SOFC).

  19. Fundamental Investigation of Si Anode in Li-Ion Cells

    Science.gov (United States)

    Wu, James J.; Bennett, William R.

    2012-01-01

    Silicon is a promising and attractive anode material to replace graphite for high capacity lithium ion cells since its theoretical capacity is approximately 10 times of graphite and it is an abundant element on earth. However, there are challenges associated with using silicon as Li-ion anode due to the significant first cycle irreversible capacity loss and subsequent rapid capacity fade during cycling. In this paper, cyclic voltammetry and electrochemical impedance spectroscopy are used to build a fundamental understanding of silicon anodes. The results show that it is difficult to form the SEI film on the surface of Si anode during the first cycle, the lithium ion insertion and de-insertion kinetics for Si are sluggish, and the cell internal resistance changes with the state of lithiation after electrochemical cycling. These results are compared with those for extensively studied graphite anodes. The understanding gained from this study will help to design better Si anodes.

  20. Redox Stable Anodes for Solid Oxide Fuel Cells

    Directory of Open Access Journals (Sweden)

    Guoliang eXiao

    2014-06-01

    Full Text Available Solid oxide fuel cells (SOFCs can convert chemical energy from the fuel directly to electrical energy with high efficiency and fuel flexibility. Ni-based cermets have been the most widely adopted anode for SOFCs. However, the conventional Ni-based anode has low tolerance to sulfur-contamination, is vulnerable to deactivation by carbon build-up (coking from direct oxidation of hydrocarbon fuels, and suffers volume instability upon redox cycling. Among these limitations, the redox instability of the anode is particularly important and has been intensively studied since the SOFC anode may experience redox cycling during fuel cell operations even with the ideal pure hydrogen as the fuel. This review aims to highlight recent progresses on improving redox stability of the conventional Ni-based anode through microstructure optimization and exploration of alternative ceramic-based anode materials.

  1. Disodium terephthalate (Na{sub 2}C{sub 8}H{sub 4}O{sub 4}) as high performance anode material for low-cost room-temperature sodium-ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Liang; Hu, Yong-Sheng; Li, Hong; Armand, Michel; Chen, Liquan [Key Laboratory for Renewable Energy, Beijing Key Laboratory for New, Energy Materials and Devices, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing (China); Zhao, Junmei [Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing (China); Zhou, Zhibin [School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan (China)

    2012-08-15

    In this contribution, a cheap organic material, disodium terephthalate, Na{sub 2}C{sub 8}H{sub 4}O{sub 4}, has been firstly evaluated as a novel anode for room-temperature Na-ion batteries. The material exhibits a high reversible capacity of 250 mAh/g with excellent cycleability. The average Na storage voltage is approximately 0.43 V vs. Na{sup +}/Na. A thin layer of Al{sub 2}O{sub 3} coating on the electrode surface derived from the atomic layer deposition technique is effective in further enhancing Na storage performance. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Anodic oxidation of benzoquinone using diamond anode.

    Science.gov (United States)

    Panizza, Marco

    2014-01-01

    The anodic degradation of 1,4-benzoquinone (BQ), one of the most toxic xenobiotic, was investigated by electrochemical oxidation at boron-doped diamond anode. The electrolyses have been performed in a single-compartment flow cell in galvanostatic conditions. The influence of applied current (0.5-2 A), BQ concentration (1-2 g dm(-3)), temperature (20-45 °C) and flow rate (100-300 dm(3) h(-1)) has been studied. BQ decay kinetic, the evolution of its oxidation intermediates and the mineralization of the aqueous solutions were monitored during the electrolysis by high-performance liquid chromatograph (HPLC) and chemical oxygen demand (COD) measurements. The results obtained show that the use of diamond anode leads to total mineralization of BQ in any experimental conditions due to the production of oxidant hydroxyl radicals electrogenerated from water discharge. The decay kinetics of BQ removal follows a pseudo-first-order reaction, and the rate constant increases with rising current density. The COD removal rate was favoured by increasing of applied current, recirculating flow rate and it is almost unaffected by solution temperature. PMID:24710725

  3. Battery, especially for portable devices, has an anode containing silicon

    NARCIS (Netherlands)

    Kan, S.Y.

    2002-01-01

    The anode (2) contains silicon. A battery with a silicon-containing anode is claimed. An Independent claim is also included for a method used to make the battery, comprising the doping of a silicon substrate (1) with charge capacity-increasing material (preferably boron, phosphorous or arsenic), etc

  4. New development of anodizing process of magnesium alloys

    Institute of Scientific and Technical Information of China (English)

    BAI Li-qun; LI Di

    2004-01-01

    Magnesium alloy, a kind of environment-friendly material with promising and excellent properties, is a good choice for a number of applications. The research and development of anodizing on magnesium alloys and its application situation are reviewed, and the anodizing development trend on magnesium alloys is summarized.

  5. Planar metal-supported SOFC with novel cermet anode

    DEFF Research Database (Denmark)

    Blennow Tullmar, Peter; Hjelm, Johan; Klemensø, Trine; Persson, Åsa Helen; Ramousse, Severine; Mogensen, Mogens Bjerg

    2011-01-01

    Metal-supported solid oxide fuel cells are expected to offer several potential advantages over conventional anode (Ni-YSZ) supported cells. For example, increased resistance against mechanical and thermal stresses and a reduction in material costs. When Ni-YSZ based anodes are used in metal suppo...

  6. Development of Planar Metal Supported SOFC with Novel Cermet Anode

    DEFF Research Database (Denmark)

    Blennow Tullmar, Peter; Hjelm, Johan; Klemensø, Trine; Persson, Åsa Helen; Brodersen, Karen; Srivastava, Akhilesh Kumar; Frandsen, Henrik Lund; Lundberg, Mats; Ramousse, Severine; Mogensen, Mogens Bjerg

    2009-01-01

    Metal-supported solid oxide fuel cells are expected to offer several potential advantages over conventional anode (Ni-YSZ) supported cells, such as increased resistance against mechanical and thermal stresses and a reduction in materials cost. When Ni-YSZ based anodes are used in metal supported ...

  7. Low cost fuel cell diffusion layer configured for optimized anode water management

    Science.gov (United States)

    Owejan, Jon P; Nicotera, Paul D; Mench, Matthew M; Evans, Robert E

    2013-08-27

    A fuel cell comprises a cathode gas diffusion layer, a cathode catalyst layer, an anode gas diffusion layer, an anode catalyst layer and an electrolyte. The diffusion resistance of the anode gas diffusion layer when operated with anode fuel is higher than the diffusion resistance of the cathode gas diffusion layer. The anode gas diffusion layer may comprise filler particles having in-plane platelet geometries and be made of lower cost materials and manufacturing processes than currently available commercial carbon fiber substrates. The diffusion resistance difference between the anode gas diffusion layer and the cathode gas diffusion layer may allow for passive water balance control.

  8. 锂离子电池负极材料Li4Ti5O12的研究概况%Research on Li4Ti5O12anode materials for lithium-ion battery

    Institute of Scientific and Technical Information of China (English)

    樊勇利; 李文升

    2011-01-01

    The research development of anode materials Li4Ti5O12 for Li-ion battery was reviewed in the recent ten years, including structure, synthesis, modification, application. and etc., which was expected to provide some help for commerical applications of LiTiO12 anode, realize some techical breaks, and explore the earlier apolication to power Li-ion battery.%对近10年来锂离子电池负极材料Li4 Ti5 O(12)研究概况如结构、合成方法、改性、应用等方面情况进行综述,以期在Li4Ti5012的商业化应用研究方面提供帮助,实现一些技术突破,为Li4Ti5O12早日应用于动力锂离子电池上做一些探索.

  9. Thin layers elaborated from new anodic and cathodic materials for lithium-ions micro-batteries; Nouveaux materiaux d'electrodes elabores sous forme de couches minces pour batteries lithium-ion

    Energy Technology Data Exchange (ETDEWEB)

    Benjelloun, N.

    2002-12-01

    Thin layers elaborated by R.F. sputtering from new anodic and cathodic materials were investigated as electrodes for lithium-ion micro-batteries. Anodic thin films based on the Tin Composite Oxides (TCOs) were found to exhibit interesting electrochemical characteristics. However, the irreversible capacity loss occurring during the first charge and due to the reduction of tin oxide remains a drawback. According to the gold collector contribution to the faradic yield, electrochemical behavior of metallic thin films (Au, Ag, Cu, Zn, etc...) was studied. AuCuAg and Ag based thin films were associated via an aprotic or solid electrolyte (LiPON) to Li{sub 1+x}Mn{sub 1,5}Ni{sub 0,5}O{sub 4} thin layers in order to build up mini or micro batteries with an average voltage close to 4,7 V. However, all solid state micro-batteries were found to present high ohmic drop. (author)

  10. Optimal Conditions for Fast Charging and Long Cycling Stability of Silicon Microwire Anodes for Lithium Ion Batteries, and Comparison with the Performance of Other Si Anode Concepts

    Directory of Open Access Journals (Sweden)

    Enrique Quiroga-González

    2013-10-01

    Full Text Available Cycling tests under various conditions have been performed for lithium ion battery anodes made from free-standing silicon microwires embedded at one end in a copper current collector. Optimum charging/discharging conditions have been found for which the anode shows negligible fading (< 0.001% over 80 cycles; an outstanding result for this kind of anodes. Several performance parameters of the anode have been compared to the ones of other Si anode concepts, showing that especially the capacity as well as the rates of charge flow per nominal area of anode are the highest for the present anode. With regard to applications, the specific parameters per area are more important than the specific gravimetric parameters like the gravimetric capacity, which is good for comparing the capacity between materials but not enough for comparing between anodes.

  11. Phase-pure β-NiMoO4 yolk-shell spheres for high-performance anode materials in lithium-ion batteries

    International Nuclear Information System (INIS)

    Phase-pure β-NiMoO4 yolk-shell spheres for lithium-ion battery anodes were prepared for the first time by one-pot spray pyrolysis, and their electrochemical properties were investigated. The yolk-shell-structured β-NiMoO4 powders exhibited high initial discharge/charge capacities (1634/1253 mA h g−1) at a current density of 1000 mA g−1. After 200 cycles, these powders exhibited a high discharge capacity of 1292 mA h g−1, whereas the initial discharge capacity (1341 mA h g−1) of the filled structured NiMoO4 powders was dramatically decreased to 479 mA h g−1. The significant enhancement of the cycling performance of the β-NiMoO4 powders with ultrafine crystallite size was attributed to the structural stability of the yolk-shell structure

  12. Anodic Stripping Voltammetry: An Instrumental Analysis Experiment.

    Science.gov (United States)

    Wang, Joseph

    1983-01-01

    Describes an experiment designed to acquaint students with the theory and applications of anodic stripping voltammetry (ASV) as well as such ASV problems as contamination associated with trace analysis. The experimental procedure, instrumentation, and materials discussed are designed to minimize cost and keep procedures as simple as possible. (JM)

  13. Study on selenium extraction from anode slime

    Institute of Scientific and Technical Information of China (English)

    GU; Heng

    2005-01-01

    Taking a copper anode slime as the raw material, a novel process for selenium extraction was studied. The primary selenium recovery can reach above 88.5 % and the quality index of selenium product can be up to 99.5 %. The economic benefit resulted is remarkable and environment has been protected.

  14. Improving Efficiency of Aluminium Sacrificial Anode Using Cold Work Process

    Science.gov (United States)

    Asmara, Y. P.; Siregar, J. P.; Tezara, C.; Ann, Chang Tai

    2016-02-01

    Aluminium is one of the preferred materials to be used as sacrificial anode for carbon steel protection. The efficiency of these can be low due to the formation of oxide layer which passivate the anodes. Currently, to improve its efficiency, there are efforts using a new technique called surface modifications. The objective of this research is to study corrosion mechanism of aluminium sacrificial anode which has been processed by cold work. The cold works are applied by reducing the thickness of aluminium sacrificial anodes at 20% and 40% of thickness reduction. The cathodic protection experiments were performed by immersion of aluminium connected to carbon steel cylinder in 3% NaCl solutions. Visual inspections using SEM had been conducted during the experiments and corrosion rate data were taken in every week for 8 weeks of immersion time. Corrosion rate data were measured using weight loss and linear polarization technique (LPR). From the results, it is observed that cold worked aluminium sacrificial anode have a better corrosion performance. It shows higher corrosion rate and lower corrosion potential. The anodes also provided a long functional for sacrificial anode before it stop working. From SEM investigation, it is shown that cold works have changed the microstructure of anodes which is suspected in increasing corrosion rate and cause de-passivate of the surface anodes.

  15. SnO2/carbon nanotube nanocomposites synthesized in supercritical fluids: highly efficient materials for use as a chemical sensor and as the anode of a lithium-ion battery

    Science.gov (United States)

    An, Guimin; Na, Na; Zhang, Xinrong; Miao, Zhenjiang; Miao, Shiding; Ding, Kunlun; Liu, Zhimin

    2007-10-01

    SnO2/multi-walled carbon nanotube (MWCNT) nanocomposites were prepared via oxidation of SnCl2 in a supercritical CO2-methanol mixture containing MWCNTs. The as-prepared nanocomposites were characterized by means of x-ray diffraction, x-ray photoelectron spectroscopy, and transmission electron microscopy. It was indicated that SnO2 nanoparticles with size of 3-5 nm were uniformly and tightly decorated on the MWCNTs. The chemiluminescence characteristic to H2S and electrochemical performance of the as-prepared SnO2/MWCNT composites were investigated. The SnO2/MWCNT composites exhibited extremely high efficiency for detecting H2S, and also displayed good electrochemical performance as the anode material in a lithium-ion battery.

  16. A- and B-site doping effect on physicochemical properties of Sr2‑xBaxMMoO6 (M = Mg, Mn, Fe) double perovskites — candidate anode materials for SOFCs

    Science.gov (United States)

    Zheng, Kun; Świerczek, Konrad

    2016-06-01

    In this work, we evaluate the physicochemical properties of Sr2‑xBaxMMoO6 (M = Mg, Mn, Fe) double perovskites as alternative anode materials for solid oxide fuel cells, for which the effect of substitution of strontium by barium in a full range of compositions is studied. The crystal structure, microstructure, characterization of transport properties (electrical conductivity, Seebeck coefficient) and oxygen content as a function of temperature, as well as chemical stability in oxidizing and reducing conditions are discussed. Fe- and Mo-containing Sr2‑xBaxFeMoO6 oxides show very high total conductivities with values of 100-1000 Sṡcm‑1, while Sr2‑xBaxMgMoO6 present good redox stability.

  17. SnO2/carbon nanotube nanocomposites synthesized in supercritical fluids: highly efficient materials for use as a chemical sensor and as the anode of a lithium-ion battery

    International Nuclear Information System (INIS)

    SnO2/multi-walled carbon nanotube (MWCNT) nanocomposites were prepared via oxidation of SnCl2 in a supercritical CO2-methanol mixture containing MWCNTs. The as-prepared nanocomposites were characterized by means of x-ray diffraction, x-ray photoelectron spectroscopy, and transmission electron microscopy. It was indicated that SnO2 nanoparticles with size of 3-5 nm were uniformly and tightly decorated on the MWCNTs. The chemiluminescence characteristic to H2S and electrochemical performance of the as-prepared SnO2/MWCNT composites were investigated. The SnO2/MWCNT composites exhibited extremely high efficiency for detecting H2S, and also displayed good electrochemical performance as the anode material in a lithium-ion battery

  18. Facile synthesis of MgCo2O4 nanowires as binder-free flexible anode materials for high-performance Li-ion batteries

    International Nuclear Information System (INIS)

    MgCo2O4 nanowires are synthesized for the first time through two-step synthesis method, followed by annealing of the MgCo2O4 precursors. The microstructure and morphology of MgCo2O4 nanowires are examined by powder X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. MgCo2O4 nanowires give rise to a BET surface area of 45.1 m2 g−1 and the adsorption average pore size of 11.5 nm. When tested as an anode for lithium-ion batteries, the MgCo2O4 nanowires electrode exhibit exceptional properties in terms of specific capacity, cycling performance, and rate capacity compared with previously reported Co-based binary metal oxides. For instance, when the current densities increase from 5, 10, 15, and 20 A g−1, the discharge capacities of the MgCo2O4 nanowires electrode are about 649, 348, 188, and 121 mAh g−1, respectively. The enhanced electrochemical performance of the MgCo2O4 nanowires can be mainly attributed to the nanostructures which lead to decreased lithium-ion diffusion distances and increased active sites for Li insertion/extraction reactions

  19. Novel MnOx@Carbon hybrid nanowires with core/shell architecture as highly reversible anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Novel MnOx@Carbon hybrid nanowires were successfully synthesized by the combination of a hydrothermal process and a simple PVP (polyvinylpyrrolidone) – solution-soaking method followed by a subsequent carbonization treatment. The nanostructures exhibit the unique feature of having nanocrystalline manganese oxide particle encapsulated inside and an amorphous carbon layer coating the outside. The unique porous characteristics with many meso/micro-pores, and further the highly conductive carbon matrix would lead to the excellent electrochemical performance of the MnOx@Carbon nanowire electrode. The MnOx@Carbon hybrid nanowires exhibit a high initial reversible capacity of 824.4 mAhg−1, a reversible capacity of approximately 541 mAhg−1 after 54 cycles, and excellent cycling stability and rate capability with specific capacity of 298.24 mAhg−1 when cycled at the current density of 1000 mAg−1, which indicates that the composite is a promising anode candidate for Li-ion batteries. - Highlights: • MnOx@C composite were obtained by hydrothermal and PVP-solution-soaking method. • The structures is characteristic of MnOx nanocrystals coated into carbon matrix. • The electrode exhibits good Li+ capacities, cycling stability and rate capability

  20. Highly porous Ti/SnO2 network composite film as stable binder-free anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • A 3D porous Ti/SnO2 network film was designed and prepared. • The 3D network composites consists of Ti core and SnO2 shell. • The 3D network film shows promising capacity and enhanced cycling performance. - Abstract: Electrodes with three-dimensional (3D) nanostructure are expected to improve the energy and power densities of lithium ion batteries. Herein, we report a 3D porous Ti/SnO2 nanocomposite which was prepared by a novel experimental procedure combining the dealloying technique and hydrothermal treatment. Its structure and electrochemical properties were investigated with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray (EDX) spectroscopy and galvanostatic charge–discharge tests. The results of electrochemical tests showed that the porous composite anode presented the largest reversible capacity of 616.0 mA h g−1 at the first cycle; and it still delivered a reversible Li storage capacity of 432.5 mA h g−1 after 100 cycles. Our work suggests the possibility of further improving the specific capacity/energy density of 3D microelectrodes by designing ordered hybrid nanostructure arrays

  1. Double anodization experiments in tantalum

    Energy Technology Data Exchange (ETDEWEB)

    Albella, J.M.; Fernandez, M.; Gomez-Aleixandre, C.; Martinez-Duart, J.M.; Montero, I.

    1985-10-01

    Based on our previous model of anodization, a new formula is given for the relation between the breakdown voltage V /SUB B/ during the anodic oxidation of tantalum and the anodization parameters. The formula predicts the well known diminution of V /SUB B/ with the logarithm of the electrolyte concentration. The model also explains the experimentally-observed fact that V /SUB B/ is solely determined by the latter electrolyte in double anodization experiments.

  2. Inert Anode Report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1999-07-01

    This ASME report provides a broad assessment of open literature and patents that exist in the area of inert anodes and their related cathode systems and cell designs, technologies that are relevant for the advanced smelting of aluminum. The report also discusses the opportunities, barriers, and issues associated with these technologies from a technical, environmental, and economic viewpoint.

  3. Effects of structural patterns and degree of crystallinity on the performance of nanostructured ZnO as anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Liang, E-mail: xiaoliang@whut.edu.cn; Mei, Daidi; Cao, Minglei; Qu, Deyu; Deng, Bohua

    2015-04-05

    Highlights: • Effects of structural patterns on nanostructured ZnO anode are studied. • Structural patterns with sufficient inner spacing show better capacity retention. • Capacity of nanostructured ZnO increase with the increasing of crystallinity. • Crystallized ZnO with inner spacing are expected to have good performance. - Abstract: The effects of structural patterns and degree of crystallinity on the electrochemical performance of ZnO were systematically studied using a controllable synthesis. The microspheres assembled with distorted nanosheets, hexagonal nanorods and radial assembly of nanorods of ZnO were successfully prepared by the hydrothermal reaction of zinc nitrate, hexamethylenetetramine and different amount of trisodium citrate. ZnO microspheres were calcinated at different temperatures (300, 600 and 900 °C) to increase their degree of crystallization. Constant current charge and discharge measurements show that the capacity retention of the microspheres and radial assembled nanorods are higher than that of hexagonal nanorods. This may be due to their inner spacing of specific structure patterns that can accommodate and restrain the volume changes during cycling. Additionally, the capacity of ZnO microspheres can be improved by short-time calcinations at 600 or 900 °C for their crystallization. The studies of differential capacity versus potential plots indicate that the enhanced degree of crystallization facilitates the alloying and dealloying of the reduction products of ZnO. Therefore, both large specific capacity and good capacity retention can be expected with highly crystallized specific nanostructures of ZnO with the sufficient inner spacing. The ZnO microspheres calcinated at 600 °C show the best performance with a specific capacity of 1328.2 mA h g{sup −1} for the first cycle and 662.8 mA h g{sup −1} for the 50th cycle at 0.1 C with an operating potential of 0.05–3.00 V.

  4. Facile synthesis of MgCo{sub 2}O{sub 4} nanowires as binder-free flexible anode materials for high-performance Li-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiujuan; Zhai, Gaohong, E-mail: zgh@nwu.edu.cn; Wang, Hui, E-mail: hwangnwu@sina.cn, E-mail: huiwang@nwu.edu.cn [Northwest University, Key Laboratory of Synthetic and Natural Functional Molecule Chemistry (Ministry of Education), College of Chemistry & Materials Science (China)

    2015-08-15

    MgCo{sub 2}O{sub 4} nanowires are synthesized for the first time through two-step synthesis method, followed by annealing of the MgCo{sub 2}O{sub 4} precursors. The microstructure and morphology of MgCo{sub 2}O{sub 4} nanowires are examined by powder X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. MgCo{sub 2}O{sub 4} nanowires give rise to a BET surface area of 45.1 m{sup 2} g{sup −1} and the adsorption average pore size of 11.5 nm. When tested as an anode for lithium-ion batteries, the MgCo{sub 2}O{sub 4} nanowires electrode exhibit exceptional properties in terms of specific capacity, cycling performance, and rate capacity compared with previously reported Co-based binary metal oxides. For instance, when the current densities increase from 5, 10, 15, and 20 A g{sup −1}, the discharge capacities of the MgCo{sub 2}O{sub 4} nanowires electrode are about 649, 348, 188, and 121 mAh g{sup −1}, respectively. The enhanced electrochemical performance of the MgCo{sub 2}O{sub 4} nanowires can be mainly attributed to the nanostructures which lead to decreased lithium-ion diffusion distances and increased active sites for Li insertion/extraction reactions.

  5. Three-dimensional structure-based tin disulfide/vertically aligned carbon nanotube arrays composites as high-performance anode materials for lithium ion batteries

    Science.gov (United States)

    Deng, Weina; Chen, Xiaohua; Liu, Zheng; Hu, Aiping; Tang, Qunli; Li, Zhe; Xiong, Yina

    2015-03-01

    Three-dimensional (3D) structure-based tin disulfide/vertically aligned carbon nanotube arrays (VACNTs) composites have been successfully fabricated via a facile hydrothermal method for self-assembly with the help of nebulization-assisted infiltration. The SnS2 particles are anchored on the surface of the VACNTs and the number of these nanoparticles increases as the nebulization time increase. The novel 3D structure-based SnS2/VACNTs sample with the SnS2 content of 67 wt% exhibits excellent electrochemical performance, including high capacity (738 mA h g-1 at 50 mA g-1 after 1st cycle), good cycle stability (551 mA h g-1 at 100 mA g-1after 100 cycles), and excellent rate capability (223 mA h g-1 at 2000 mA g-1) when used as an anode in lithium ion batteries. The high electrochemical performance can be attributed to the synergistic effect of SnS2 and the unique microstructure of VACNTs, which provide the rapid pathways for ionic and electronic transport ascribing to their well-directed 1D conductive electron paths and well defined regular pore structures. The VACNTs serve as not only conductive additives to improve the conductivity of SnS2 in the composites, but also as buffer matrix to restrain the volume change of SnS2 and stabilize the electrode structure during the alloying/dealloying process.

  6. Research Progress of High Capacity Si Based Anode Material for Li-Ion Battery%锂离子电池用高容量合金类硅基负极材料研究进展

    Institute of Scientific and Technical Information of China (English)

    沈龙; 董爱想; 乔永民; 吴敏昌

    2012-01-01

      锡、硅负极材料由于具有高的比容量等优点,成为提高锂离子电池能量密度的首选负极材料。首先介绍了目前产业界开发锡、硅负极材料的进展,并从商业化的角度比较了这两类材料在开发工艺及实际使用电性能方面的区别。进一步从基础研发角度重点阐述了不同结构的硅基材料(单质硅、硅氧化物、硅碳复合物及硅合金)的电性能改性研究进展,指出了具有工业化前景的工艺方法。%  Tin and Silicon-based compounds are the research focuses of high capacity anode material for lithium ion batteries. The research progress of Si&Sn materials is introduced, and their process development from commercial perspective is also compared. The electrochemical behaviors modification progresses of Si materials, which are crystal silicon、silicon oxygen compound, Si/C composite and silicon alloy, have been reported. The process route which is fit for industrialization has been provided.

  7. Improving the electrochemical properties of Al, Zr Co-doped Li{sub 4}Ti{sub 5}O{sub 12} as a lithium-ion battery anode material

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jung Soo; Baek, Seong Ho; Park, Yi Seul; Kim, Jae Hyun [Daegu-Gyeongbuk Institute of Science and Technology, Daegu (Korea, Republic of)

    2014-05-15

    Li{sub 4}Ti{sub 5}O{sub 12} and Al{sup 3+}, Zr{sup 4+} co-doped Li{sub (4-x/3)}Al{sub x}Ti{sub (5-5x/3)}Zr{sub x}O{sub 12} (x = 0.01, 0.05, 0.1, 0.15, 0.2) were synthesized at 950 .deg. C via a solid state reaction by using rutile TiO{sub 2}, Li{sub 2}CO{sub 3}, and Al{sub 2}O{sub 3} as precursors for the anode material of a lithium-ion battery. The average particle sizes of Li{sub (4-x/3)}Al{sub x}Ti{sub (5-5x/3)}Zr{sub x}O{sub 12} (x = 0, 0.01, 0.05, 0.1, 0.15, 0.2) range from 700 to 1200 nm. The particle sizes of pure Li{sub 4}Ti{sub 5}O{sub 12} and Al{sup 3+}, Zr{sup 4+} co-doped Li{sub 4}Ti{sub 5}O{sub 12} were not obviously different, but did result in a shift in the (111) peak in X-ray diffraction. Li{sub (4-x/3)}Al{sub x}Ti{sub (5-5x/3)}Zr{sub x}O{sub 12} (x = 0.01) exhibits an excellent rate capability with a reversible capacity of 127.7 mAh/g at a 5 C-rate and even 113.1 mAh/g at a 10 C-rate. The capacity retention was improved remarkably compared to that for an undoped anode when discharged at a high C- rate.

  8. Fundamental Investigation of Silicon Anode in Lithium-Ion Cells

    Science.gov (United States)

    Wu, James J.; Bennett, William R.

    2012-01-01

    Silicon is a promising and attractive anode material to replace graphite for high capacity lithium ion cells since its theoretical capacity is 10 times of graphite and it is an abundant element on Earth. However, there are challenges associated with using silicon as Li-ion anode due to the significant first cycle irreversible capacity loss and subsequent rapid capacity fade during cycling. Understanding solid electrolyte interphase (SEI) formation along with the lithium ion insertion/de-insertion kinetics in silicon anodes will provide greater insight into overcoming these issues, thereby lead to better cycle performance. In this paper, cyclic voltammetry and electrochemical impedance spectroscopy are used to build a fundamental understanding of silicon anodes. The results show that it is difficult to form the SEI film on the surface of a Si anode during the first cycle; the lithium ion insertion and de-insertion kinetics for Si are sluggish, and the cell internal resistance changes with the state of lithiation after electrochemical cycling. These results are compared with those for extensively studied graphite anodes. The understanding gained from this study will help to design better Si anodes, and the combination of cyclic voltammetry with impedance spectroscopy provides a useful tool to evaluate the effectiveness of the design modifications on the Si anode performance.

  9. Recent anode advances in solid oxide fuel cells

    Science.gov (United States)

    Sun, Chunwen; Stimming, Ulrich

    Solid oxide fuel cells (SOFCs) are electrochemical reactors that can directly convert the chemical energy of a fuel gas into electrical energy with high efficiency and in an environment-friendly way. The recent trends in the research of solid oxide fuel cells concern the use of available hydrocarbon fuels, such as natural gas. The most commonly used anode material Ni/YSZ cermet exhibits some disadvantages when hydrocarbons were used as fuels. Thus it is necessary to develop alternative anode materials which display mixed conductivity under fuel conditions. This article reviews the recent developments of anode in SOFCs with principal emphasis on the material aspects. In addition, the mechanism and kinetics of fuel oxidation reactions are also addressed. Various processes used for the cost-effective fabrication of anode have also been summarized. Finally, this review will be concluded with personal perspectives on the future research directions of this area.

  10. Efficient and stable iron based perovskite La0.9Ca0.1Fe0.9Nb0.1O3-δ anode material for solid oxide fuel cells

    Science.gov (United States)

    Kong, Xiaowei; Zhou, Xiaoliang; Tian, Yu; Wu, Xiaoyan; Zhang, Jun; Zuo, Wei; Gong, Xiaobo; Guo, Zhanhu

    2016-06-01

    A novel La0.9Ca0.1Fe0.9Nb0.1O3-δ (LCFNb) perovskite for solid oxide fuel cells (SOFCs) anode is prepared by means of the citrate-nitrate route and composited with Ce0.8Sm0.2O1.9 (SDC) by impregnation method to form nano-scaled LCFNb/SDC anode catalytic layers. The single cells with LCFNb and LCFNb/SDC impregnated anodes both achieve relatively high power output with maximum power densities (MPDs) reaching up to 610, 823 mW·cm-2 in H2 at 800 °C, respectively, presenting a high potential of LCFNb for use as SOFCs anode. The power outputs of the single cells with LCFNb/SDC composite anode in CO and syngas (COsbnd H2 mixture) are almost identical to that in H2 at each testing temperature. This composite anode also presents excellent durability in both H2 and CO for as long as 50 h, showing desirable anti-reduction and carbon deposition resistance abilities. Besides, the cell output is stable in 100 ppm H2Ssbnd H2 atmospheres for 20 h at a current density of 600 mA·cm-2 with negligible sulfur accumulation on the anode surface. Hence, a novel iron based perovskite LCFNb anode with remarkable cell performance, carbon deposition resistance and sulfur poisoning tolerance for SOFCs is successfully obtained.

  11. Anodic bonded graphene

    OpenAIRE

    Balan, Adrian; Kumar, Rakesh; Boukhicha, Mohamed; Beyssac, Olivier; Bouillard, Jean-Claude; Taverna, Dario; Sacks, William; Marangolo, Massimiliano; Lacaze, Emmanuelle; Escoffier, Walter; Poumirol, Jean-Marie; Shukla, Abhay

    2010-01-01

    Abstract We show how to prepare graphene samples on a glass substrate with the anodic bonding method. In this method, a graphite precursor in flake form is bonded to a glass substrate with the help of an electrostatic field and then cleaved off to leave few layer graphene on the substrate. Now that several methods are available for producing graphene, the relevance of our method is in its simplicity and practicality for producing graphene samples of about 100 ?m lateral dimensions. This me...

  12. Perovskites synthesis to SOFC anodes

    International Nuclear Information System (INIS)

    Perovskite structure materials containing lanthanum have been widely applied as solid oxide fuel cells (SOFCs) electrodes, due to its electrical properties. Was investigated the obtain of the perovskite structure LaCr0,5Ni0,5O3, by Pechini method, and its suitability as SOFC anode. The choice of this composition was based on the stability provided by chromium and the catalytic properties of nickel. After preparing the resins, the samples were calcined at 300 deg C, 600 deg C, 700 deg C and 850 deg C. The resulting powders were characterized by X-ray diffraction to determine the existing phases. Furthermore, were performed other analysis, like X-ray fluorescence, He pycnometry, specific surface area by BET isotherm and scanning electronic microscopy (author)

  13. Laser-Ultrasonic Measurement of Elastic Properties of Anodized Aluminum Coatings

    Science.gov (United States)

    Singer, F.

    Anodized aluminum oxide plays a great role in many industrial applications, e.g. in order to achieve greater wear resistance. Since the hardness of the anodized films strongly depends on its processing parameters, it is important to characterize the influence of the processing parameters on the film properties. In this work the elastic material parameters of anodized aluminum were investigated using a laser-based ultrasound system. The anodized films were characterized analyzing the dispersion of Rayleigh waves with a one-layer model. It was shown that anodizing time and temperature strongly influence Rayleigh wave propagation.

  14. High-capacity nanocarbon anodes for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • The nanocarbon anodes in lithium-ion batteries deliver a high capacity of ∼1100 mA h g−1. • The nanocarbon anodes exhibit excellent cyclic stability. • A novel structure of carbon materials, hollow carbon nanoboxes, has potential application in lithium-ion batteries. - Abstract: High energy and power density of secondary cells like lithium-ion batteries become much more important in today’s society. However, lithium-ion battery anodes based on graphite material have theoretical capacity of 372 mA h g−1 and low charging-discharging rate. Here, we report that nanocarbons including mesoporous graphene (MPG), carbon tubular nanostructures (CTN), and hollow carbon nanoboxes (HCB) are good candidate for lithium-ion battery anodes. The nanocarbon anodes have high capacity of ∼1100, ∼600, and ∼500 mA h g−1 at 0.1 A g−1 for MPG, CTN, and HCB, respectively. The capacity of 181, 141, and 139 mA h g−1 at 4 A g−1 for MPG, CTN, and HCB anodes is retained. Besides, nanocarbon anodes show high cycling stability during 1000 cycles, indicating formation of a passivating layer—solid electrolyte interphase, which support long-term cycling. Nanocarbons, constructed with graphene layers which fulfill lithiation/delithiation process, high ratio of graphite edge structure, and high surface area which facilitates capacitive behavior, deliver high capacity and improved rate-capability

  15. Nanostructural Engineering of Nanoporous Anodic Alumina for Biosensing Applications

    Directory of Open Access Journals (Sweden)

    Josep Ferré-Borrull

    2014-07-01

    Full Text Available Modifying the diameter of the pores in nanoporous anodic alumina opens new possibilities in the application of this material. In this work, we review the different nanoengineering methods by classifying them into two kinds: in situ and ex situ. Ex situ methods imply the interruption of the anodization process and the addition of intermediate steps, while in situ methods aim at realizing the in-depth pore modulation by continuous changes in the anodization conditions. Ex situ methods permit a greater versatility in the pore geometry, while in situ methods are simpler and adequate for repeated cycles. As an example of ex situ methods, we analyze the effect of changing drastically one of the anodization parameters (anodization voltage, electrolyte composition or concentration. We also introduce in situ methods to obtain distributed Bragg reflectors or rugate filters in nanoporous anodic alumina with cyclic anodization voltage or current. This nanopore engineering permits us to propose new applications in the field of biosensing: using the unique reflectance or photoluminescence properties of the material to obtain photonic barcodes, applying a gold-coated double-layer nanoporous alumina to design a self-referencing protein sensor or giving a proof-of-concept of the refractive index sensing capabilities of nanoporous rugate filters.

  16. Interconnected hollow carbon nanospheres for stable lithium metal anodes.

    Science.gov (United States)

    Zheng, Guangyuan; Lee, Seok Woo; Liang, Zheng; Lee, Hyun-Wook; Yan, Kai; Yao, Hongbin; Wang, Haotian; Li, Weiyang; Chu, Steven; Cui, Yi

    2014-08-01

    For future applications in portable electronics, electric vehicles and grid storage, batteries with higher energy storage density than existing lithium ion batteries need to be developed. Recent efforts in this direction have focused on high-capacity electrode materials such as lithium metal, silicon and tin as anodes, and sulphur and oxygen as cathodes. Lithium metal would be the optimal choice as an anode material, because it has the highest specific capacity (3,860 mAh g(-1)) and the lowest anode potential of all. However, the lithium anode forms dendritic and mossy metal deposits, leading to serious safety concerns and low Coulombic efficiency during charge/discharge cycles. Although advanced characterization techniques have helped shed light on the lithium growth process, effective strategies to improve lithium metal anode cycling remain elusive. Here, we show that coating the lithium metal anode with a monolayer of interconnected amorphous hollow carbon nanospheres helps isolate the lithium metal depositions and facilitates the formation of a stable solid electrolyte interphase. We show that lithium dendrites do not form up to a practical current density of 1 mA cm(-2). The Coulombic efficiency improves to ∼ 99% for more than 150 cycles. This is significantly better than the bare unmodified samples, which usually show rapid Coulombic efficiency decay in fewer than 100 cycles. Our results indicate that nanoscale interfacial engineering could be a promising strategy to tackle the intrinsic problems of lithium metal anodes. PMID:25064396

  17. Anode glow and double layer in DC magnetron anode plasma

    International Nuclear Information System (INIS)

    Sputtering magnetron is widely used device in research and industry alike. DC planar magnetron employs series of magnets to create magnetic field above the electrode surface which traps electrons in closed E-bar x B-bar drift. Similar device used in reversed polarity power was reported for use in various applications. In contrast to its normal counterpart there is no closed drift effect in there. This device has very limited understanding. We here investigate this device for its discharge properties. Our device is dominated by anode glow. The anode glow is expected to have the electron sheath which provides energy to electron to excite the neutrals. Where as many experimental studies have been reported for anode glow and anode double layer, many of them uses auxiliary anode in the discharge. Most of the cases anode double layer (fire ball/fire rod) is small structures very near to anode surface which in itself is required to be small. The DC planar magnetron biased in reverse polarity have glow only near anode. Measurements confirm it as anode glow and the presence of electrons sheath is proven. The double layer structure was observed and measured in two mutually perpendicular directions. The double layer shows sub MHz oscillation that is typical of the unstable anode double layer. The dimension of anode glow is relatively large and is primarily in magnetic field free region making it easy to probe. The potential structure still shows large cathode fall but surprisingly visible cathode glow is not present. The device operates very stable for pressure bellow 0.01 mbar. But it shows instabilities such as unstable anode double layer above said pressure. (author)

  18. Process for anodizing aluminum foil

    International Nuclear Information System (INIS)

    In an integrated process for the anodization of aluminum foil for electrolytic capacitors including the formation of a hydrous oxide layer on the foil prior to anodization and stabilization of the foil in alkaline borax baths during anodization, the foil is electrochemically anodized in an aqueous solution of boric acid and 2 to 50 ppm phosphate having a pH of 4.0 to 6.0. The anodization is interrupted for stabilization by passing the foil through a bath containing the borax solution having a pH of 8.5 to 9.5 and a temperature above 800 C. and then reanodizing the foil. The process is useful in anodizing foil to a voltage of up to 760 V

  19. The effect of antimony presence in anodic copper on kinetics and mechanism of anodic dissolution and cathodic deposition of copper

    Directory of Open Access Journals (Sweden)

    Stanković Z.D.

    2008-01-01

    Full Text Available The influence of the presence of Sb atoms, as foreign metal atoms in anode copper, on kinetics, and, on the mechanism of anodic dissolution and cathodic deposition of copper in acidic sulfate solution has been investigated. The galvanostatic single-pulse method has been used. Results indicate that presence of Sb atoms in anode copper increase the exchange current density as determined from the Tafel analysis of the electrode reaction. It is attributed to the increase of the crystal lattice parameter determined from XRD analysis of the electrode material.

  20. Photoelectrochemical cell with nondissolving anode

    Science.gov (United States)

    Ellis, A. B.; Kaiser, S. W.; Wrighton, M. S.

    1980-01-01

    Improved electrolytic cells have efficiencies comparable to those of best silicon solar cells but are potentially less expensive to manufacture. Cells consist of light-sensitive n-type semiconductor anode and metallic cathode immersed in electrolytic solution. Reversible redox cells produce no chemical change in electrolyte and stabilize anode against dissolving. Cell can produce more than 500 mW of power per square centimeter of anode area at output voltage of 0.4 V.