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Arumugam Manthiram - One of the best experts on this subject based on the ideXlab platform.

  • high energy high rate lithium sulfur batteries synergetic effect of hollow tio2 webbed Carbon nanotubes and a dual functional Carbon Paper interlayer
    Advanced Energy Materials, 2016
    Co-Authors: Jang Yeon Hwang, Ali Abouimrane, Mohammad A Khaleel, Ilias Belharouak, Arumugam Manthiram
    Abstract:

    A novel nanocomposite cathode consisting of sulfur and hollow-mesoporous titania (HMT) embedded within Carbon nanotubes (CNT), which is designated as S-HMT@CNT, has been obtained by encapsulating elemental sulfur into the pores of hollow-mesoporous, spherical TiO2 particles that are connected via CNT. A Carbon-Paper interlayer, referred to as dual functional porous Carbon wall (DF-PCW), has been obtained by filling the voids in TiO2 spheres with Carbon and then etching the TiO2 template with a chemical process. The DF-PCW interlayer provides a medium for scavenging the lithium polysulfides and suppressing them from diffusing to the anode side when it is inserted between the sulfur cathode and the separator. Lithium–sulfur cells fabricated with the thus prepared S-HMT@CNT cathode and the DF-PCW interlayer exhibit superior performance due to the containment of sulfur in TiO2 and improved lithium–ion and electron transports. The Li–S cells display high capacity with excellent capacity retention at rates as high as 1C, 2C, and 5C rates.

  • improved lithium sulfur cells with a treated Carbon Paper interlayer
    Physical Chemistry Chemical Physics, 2013
    Co-Authors: Chenxi Zu, Yu-sheng Su, Yongzhu Fu, Arumugam Manthiram
    Abstract:

    A simple, low-cost modification of lithium–sulfur (Li–S) cells by placing a treated Carbon Paper between the sulfur electrode and the separator has been investigated to significantly improve the performance of Li–S cells. The treated Carbon Paper was prepared by an alcohol-alkaline/thermal treatment of a commercial Toray Carbon Paper, introducing hydroxyl functional groups and micro-cracks on the Carbon fibers in the Carbon Paper, which enhances the hydrophilicity and increases surface areas of the Carbon Paper matrix. The modified Li–S cells deliver a higher initial capacity of 1651 mAh g−1 at 1.5–2.8 V at a rate of C/5 compared to the cells without any interlayer or with an untreated Carbon Paper interlayer. The cells with the treated Carbon Paper offer additional improvement in performance when the discharge cut-off voltage is raised to 1.8 V: 1057, 1002, and 929 mAh g−1 after 100 cycles, respectively, at C/5, C/2, and 1 C rates. The improved cell performance is attributed to the 3D architecture of the Carbon Paper interlayer, serving as a conductive skeleton for trapping and depositing dissolved sulfur-containing active materials, as confirmed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The novel configuration presented here offers a low-cost approach to overcome the persistent problems of Li–S cells.

  • improved lithium sulfur cells with a treated Carbon Paper interlayer
    Physical Chemistry Chemical Physics, 2013
    Co-Authors: Arumugam Manthiram
    Abstract:

    A simple, low-cost modification of lithium–sulfur (Li–S) cells by placing a treated Carbon Paper between the sulfur electrode and the separator has been investigated to significantly improve the performance of Li–S cells. The treated Carbon Paper was prepared by an alcohol-alkaline/thermal treatment of a commercial Toray Carbon Paper, introducing hydroxyl functional groups and micro-cracks on the Carbon fibers in the Carbon Paper, which enhances the hydrophilicity and increases surface areas of the Carbon Paper matrix. The modified Li–S cells deliver a higher initial capacity of 1651 mAh g−1 at 1.5–2.8 V at a rate of C/5 compared to the cells without any interlayer or with an untreated Carbon Paper interlayer. The cells with the treated Carbon Paper offer additional improvement in performance when the discharge cut-off voltage is raised to 1.8 V: 1057, 1002, and 929 mAh g−1 after 100 cycles, respectively, at C/5, C/2, and 1 C rates. The improved cell performance is attributed to the 3D architecture of the Carbon Paper interlayer, serving as a conductive skeleton for trapping and depositing dissolved sulfur-containing active materials, as confirmed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The novel configuration presented here offers a low-cost approach to overcome the persistent problems of Li–S cells.

  • lithium sulphur batteries with a microporous Carbon Paper as a bifunctional interlayer
    Nature Communications, 2012
    Co-Authors: Arumugam Manthiram
    Abstract:

    The limitations in the cathode capacity compared with that of the anode have been an impediment to advance the lithium-ion battery technology. The lithium–sulphur system is appealing in this regard, as sulphur exhibits an order of magnitude higher capacity than the currently used cathodes. However, low active material utilization and poor cycle life hinder the practicality of lithium–sulphur batteries. Here we report a simple adjustment to the traditional lithium–sulphur battery configuration to achieve high capacity with a long cycle life and rapid charge rate. With a bifunctional microporous Carbon Paper between the cathode and separator, we observe a significant improvement not only in the active material utilization but also in capacity retention, without involving complex synthesis or surface modification. The insertion of a microporous Carbon interlayer decreases the internal charge transfer resistance and localizes the soluble polysulphide species, facilitating a commercially feasible means of fabricating the lithium–sulphur batteries. The practical performance of lithium sulphide batteries is much less than their predicted performance because redox products dissolve over time. Su and Manthiram show that microporous Carbon membranes inserted between cathode and separator localize soluble polysulphide species and improve battery cycling characteristics.

  • lithium sulphur batteries with a microporous Carbon Paper as a bifunctional interlayer
    Nature Communications, 2012
    Co-Authors: Yu-sheng Su, Arumugam Manthiram
    Abstract:

    The practical performance of lithium sulphide batteries is much less than their predicted performance because redox products dissolve over time. Su and Manthiram show that microporous Carbon membranes inserted between cathode and separator localize soluble polysulphide species and improve battery cycling characteristics.

Guoxiu Wang - One of the best experts on this subject based on the ideXlab platform.

  • 3d interconnected Carbon fiber network enabled ultralong life na3v2 po4 3 Carbon Paper cathode for sodium ion batteries
    Small, 2017
    Co-Authors: Katja Kretschmer, Jinqiang Zhang, Guoxiu Wang, Xiuqiang Xie, Bing Sun, Hao Liu
    Abstract:

    Sodium-ion batteries (NIBs) are an emerging technology, which can meet increasing demands for large-scale energy storage. One of the most promising cathode material candidates for sodium-ion batteries is Na3V2(PO4)3 due to its high capacity, thermal stability, and sodium (Na) Superionic Conductor 3D (NASICON)-type framework. In this work, the authors have significantly improved electrochemical performance and cycling stability of Na3V2(PO4)3 by introducing a 3D interconnected conductive network in the form of Carbon fiber derived from ordinary Paper towel. The free-standing Na3V2(PO4)3-Carbon Paper (Na3V2(PO4)3@CP) hybrid electrodes do not require a metallic current collector, polymeric binder, or conducting additives to function as a cathode material in an NIB system. The Na3V2(PO4)3@CP cathode demonstrates extraordinary long term cycling stability for 30 000 deep charge–discharge cycles at a current density of 2.5 mA cm−2. Such outstanding cycling stability can meet the stringent requirements for renewable energy storage.

  • mos2 nanosheets vertically aligned on Carbon Paper a freestanding electrode for highly reversible sodium ion batteries
    Advanced Energy Materials, 2016
    Co-Authors: Xiuqiang Xie, Taron Makaryan, Mengqiang Zhao, Katherine L Van Aken, Yury Gogotsi, Guoxiu Wang
    Abstract:

    The development of sodium-ion batteries for large-scale applications requires the synthesis of electrode materials with high capacity, high initial Coulombic efficiency (ICE), high rate performance, long cycle life, and low cost. A rational design of freestanding anode materials is reported for sodium-ion batteries, consisting of molybdenum disulfide (MoS2) nanosheets aligned vertically on Carbon Paper derived from Paper towel. The hierarchical structure enables sufficient electrode/electrolyte interaction and fast electron transportation. Meanwhile, the unique architecture can minimize the excessive interface between Carbon and electrolyte, enabling high ICE. The as-prepared MoS2@Carbon Paper composites as freestanding electrodes for sodium-ion batteries can liberate the traditional electrode manufacturing procedure, thereby reducing the cost of sodium-ion batteries. The freestanding MoS2@Carbon Paper electrode exhibits a high reversible capacity, high ICE, good cycling performance, and excellent rate capability. By exploiting in situ Raman spectroscopy, the reversibility of the phase transition from 2H-MoS2 to 1T-MoS2 is observed during the sodium-ion intercalation/deintercalation process. This work is expected to inspire the development of advanced electrode materials for high-performance sodium-ion batteries.

  • sn cnt nanopillars grown perpendicularly on Carbon Paper a novel free standing anode for sodium ion batteries
    Nano Energy, 2015
    Co-Authors: Xiuqiang Xie, Jinqiang Zhang, Katja Kretschmer, Bing Sun, Guoxiu Wang
    Abstract:

    Abstract Sodium-ion batteries have attracted extensive interest for energy storage and conversion as an alternative to lithium-ion batteries. The development of advanced electrode materials is important for the implementation of sodium-ion batteries into practical applications. Herein, we developed a facile soaking-chemical vapour deposition method to grow core–sheath structured Sn@CNT nanopillar arrays on Carbon Paper with a unique 3D hierarchical architecture as free-standing electrode for sodium-ion batteries. The electrode achieved a reversible capacity of 887 µA h cm −2 in the first cycle and good cyclability extending to 100 cycles. The electrode also demonstrated a promising rate capability, which is suitable for high power applications. We also assembled prototype Na-ion full cells, consisting of the as-prepared free-standing Sn@CNT@Carbon Paper anode and Na 0.80 Li 0.12 Ni 0.22 Mn 0.66 O 2 cathode. The full sodium-ion battery can power LED lights. This work is expected to inspire the development of sustainable sodium-ion batteries for energy storage and conversion.

Matthew M Mench - One of the best experts on this subject based on the ideXlab platform.

  • elucidating effects of cell architecture electrode material and solution composition on overpotentials in redox flow batteries
    Electrochimica Acta, 2017
    Co-Authors: Alan Pezeshki, Douglas Aaron, Robert L Sacci, Frank M Delnick, Matthew M Mench
    Abstract:

    An improved method for quantitative measurement of the charge transfer, finite diffusion, and ohmic overpotentials in redox flow batteries using electrochemical impedance spectroscopy is presented. The use of a pulse dampener in the hydraulic circuit enables the collection of impedance spectra at low frequencies with a peristaltic pump, allowing the measurement of finite diffusion resistances at operationally relevant flow rates. This method is used to resolve the rate-limiting processes for the V2+/V3+ redox couple on Carbon felt and Carbon Paper electrodes in the vanadium redox flow battery. Carbon felt was limited by both charge transfer and ohmic resistance, while Carbon Paper was limited by charge transfer, finite diffusion, and ohmic resistances. The influences of vanadium concentration and flow field design also are quantified.

  • Carbon nanoporous layer for reaction location management and performance enhancement in all vanadium redox flow batteries
    Journal of Power Sources, 2013
    Co-Authors: Michael P Manahan, Qinghua Liu, M L Gross, Matthew M Mench
    Abstract:

    Abstract In this study, the performance and reaction location in a VRFB was investigated with a Carbon Paper electrode that was modified to include a thin layer of multi-walled Carbon nanotubes. The nanotube layer was introduced into the electrode at locations on the negative and positive electrode nearest the membrane and nearest the flow field. Results with the nanotube layer on the positive electrode yielded small changes in the performance, despite the location. However, when the nanotube layer was introduced on the negative electrode, the performance was greatly improved when it was closest to the current collector. In this configuration, an 8% increase in power density and a 65 mV increase in cell voltage were observed, compared to a cell with raw Carbon Paper. This is attributed to the increase in active area of the nanoporous structure in a location where the reaction is favored to occur.

  • dramatic performance gains in vanadium redox flow batteries through modified cell architecture
    Journal of Power Sources, 2012
    Co-Authors: Douglas Aaron, Qinghua Liu, Zhijiang Tang, G M Grim, Alexander B Papandrew, A Turhan, Thomas A Zawodzinski, Matthew M Mench
    Abstract:

    Abstract We demonstrate a vanadium redox flow battery with a peak power density of 557 mW cm −2 at a state of charge of 60%. This power density, the highest reported to date, was obtained with a zero-gap flow field cell architecture and non-wetproofed Carbon Paper electrodes. The electrodes were comprised of stacked sheets of Carbon Paper and optimized through systematic variation of the total electrode thickness. We anticipate significant reductions in the ultimate system cost of redox flow battery systems based on this design.

Xueliang Sun - One of the best experts on this subject based on the ideXlab platform.

  • Carbon Paper interlayers: A universal and effective approach for highly stable Li metal anodes
    Nano Energy, 2018
    Co-Authors: Yang Lu-zhao, Keegan R. Adair, Yipeng Sun, Qian Sun, Ruying Li, Changhong Wang, Xia Li, Xueliang Sun
    Abstract:

    The Li metal anode is considered as one of the most promising candidates for next generation Li metal batteries (LMBs) due to the unique properties of high specific capacity, low potential and light weight. However, the crucial problems, including serious Li dendrite growth, undesired side reactions and infinite volume changes, are still big challenges for Li metal anodes, which can not only lead to the low Coulombic efficiency, but also can create short circuit risks. In this Paper, we propose a novel and universal approach to achieve long life time and dendrite-free Li metal anodes by introducing Carbon Paper (CP) as an interlayer. As a result, the as-designed electrodes can deliver extremely high capacity (up to 3 mA h cm−2 and 5 mA h cm−2), superior stable performances (620 h/265 cycles with 3 mA h cm−2) and high operational current densities (3 mA cm−2 and 5 mA cm−2). Meanwhile, the electrodes also can demonstrate high capacity and long life time in full cells using Carbon-coated LiFePO4 (C/LiFePO4) as the cathode for lithium ion batteries (LIBs) and molecular layer deposition (MLD) coated C/S as cathode for Li-S batteries. These new findings could open a new window for the fabrication of safe, long life time and dendrite-free Li metal anodes.

  • 3 d composite electrodes for high performance pem fuel cells composed of pt supported on nitrogen doped Carbon nanotubes grown on Carbon Paper
    Electrochemistry Communications, 2009
    Co-Authors: Madhu S Saha, Xueliang Sun
    Abstract:

    The 3-D composite electrodes consisting of Pt nanoparticles supported on nitrogen-doped Carbon nanotubes (CNx) grown directly on Carbon Paper were successfully prepared. The effect of the nitrogen atom incorporation in Carbon nanotubes (CNTs) on the Pt nanoparticle dispersion and catalytic activities for the oxygen reduction reaction has been investigated. Compared to regular CNTs, highly dispersed Pt nanoparticles with smaller size (2–3 nm) and higher electrochemical Pt surface area as well as higher fuel cell performance were obtained for CNx. 2008 Elsevier B.V. All rights reserved.

  • high loading and monodispersed pt nanoparticles on multiwalled Carbon nanotubes for high performance proton exchange membrane fuel cells
    Journal of Power Sources, 2008
    Co-Authors: Madhu S Saha, Xueliang Sun
    Abstract:

    Abstract Composite electrodes consisting of Pt nanoparticles-supported on multiwalled Carbon nanotubes grown directly on Carbon Paper (Pt/CNTs/Carbon Paper) have been synthesized by a new method using glacial acetic acid as a reducing agent. Transmission electron microscopy (TEM) images show that the Pt nanoparticles with high density and relative small in size (2–4 nm) were monodispersed on the surface of CNTs. X-ray photoelectron spectroscopy (XPS) analysis indicates that the glacial acetic acid acts as a reducing agent and has the capability of producing a high density of oxygen-containing functional groups on the surface of CNTs that leads to high density and monodispersion of Pt nanoparticles. Compared with standard Pt/C electrode, the Pt/CNT/Carbon Paper composite electrodes exhibit higher electrocatalytic activity for methanol oxidation reaction and higher single-cell performance in a H2/O2 fuel cell.

  • composite electrodes made of pt nanoparticles deposited on Carbon nanotubes grown on fuel cell backings
    Chemical Physics Letters, 2003
    Co-Authors: Xueliang Sun, Dominique Villers, Jeanpol Dodelet, Sylvain Desilets
    Abstract:

    Abstract Multiwalled Carbon nanotubes (MWCNTs), with typical lengths of 20 μm and diameters of 40 nm, have been grown directly on Carbon Paper backing. A sulfonic acid–silicate intermediate was used to deposit Pt particles on the MWCNTs in order to obtain an electrode that could be used in electrocatalysis. The electrical path between the Pt nanoparticles (1.2 ± 0.3 nm in size) and the Carbon Paper, through the MWCNTs, was demonstrated by cyclic voltammetry. The Pt surface density of a typical MWCNT composite electrode is estimated to be about 25% of that of an ELAT electrode from E-TEK, containing 0.4 mg Pt/cm 2 .

Yu-sheng Su - One of the best experts on this subject based on the ideXlab platform.

  • improved lithium sulfur cells with a treated Carbon Paper interlayer
    Physical Chemistry Chemical Physics, 2013
    Co-Authors: Chenxi Zu, Yu-sheng Su, Yongzhu Fu, Arumugam Manthiram
    Abstract:

    A simple, low-cost modification of lithium–sulfur (Li–S) cells by placing a treated Carbon Paper between the sulfur electrode and the separator has been investigated to significantly improve the performance of Li–S cells. The treated Carbon Paper was prepared by an alcohol-alkaline/thermal treatment of a commercial Toray Carbon Paper, introducing hydroxyl functional groups and micro-cracks on the Carbon fibers in the Carbon Paper, which enhances the hydrophilicity and increases surface areas of the Carbon Paper matrix. The modified Li–S cells deliver a higher initial capacity of 1651 mAh g−1 at 1.5–2.8 V at a rate of C/5 compared to the cells without any interlayer or with an untreated Carbon Paper interlayer. The cells with the treated Carbon Paper offer additional improvement in performance when the discharge cut-off voltage is raised to 1.8 V: 1057, 1002, and 929 mAh g−1 after 100 cycles, respectively, at C/5, C/2, and 1 C rates. The improved cell performance is attributed to the 3D architecture of the Carbon Paper interlayer, serving as a conductive skeleton for trapping and depositing dissolved sulfur-containing active materials, as confirmed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The novel configuration presented here offers a low-cost approach to overcome the persistent problems of Li–S cells.

  • lithium sulphur batteries with a microporous Carbon Paper as a bifunctional interlayer
    Nature Communications, 2012
    Co-Authors: Yu-sheng Su, Arumugam Manthiram
    Abstract:

    The practical performance of lithium sulphide batteries is much less than their predicted performance because redox products dissolve over time. Su and Manthiram show that microporous Carbon membranes inserted between cathode and separator localize soluble polysulphide species and improve battery cycling characteristics.

  • Lithium-sulphur batteries with a microporous Carbon Paper as a bifunctional interlayer
    Nature Communications, 2012
    Co-Authors: Yu-sheng Su, Arumugan Manthiram
    Abstract:

    The limitations in the cathode capacity compared with that of the anode have been an impediment to advance the lithium-ion battery technology. The lithium-sulphur system is appealing in this regard, as sulphur exhibits an order of magnitude higher capacity than the currently used cathodes. However, low active material utilization and poor cycle life hinder the practicality of lithium-sulphur batteries. Here we report a simple adjustment to the traditional lithium-sulphur battery configuration to achieve high capacity with a long cycle life and rapid charge rate. With a bifunctional microporous Carbon Paper between the cathode and separator, we observe a significant improvement not only in the active material utilization but also in capacity retention, without involving complex synthesis or surface modification. The insertion of a microporous Carbon interlayer decreases the internal charge transfer resistance and localizes the soluble polysulphide species, facilitating a commercially feasible means of fabricating the lithium-sulphur batteries.