GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • The Electrochemical Society  (75)
  • 2010-2014  (75)
  • 1
    Online Resource
    Online Resource
    Doped Transition Metal Nitride Supercapacitors (DTMSCs): Mechanisms of Charge Storage
    The Electrochemical Society ; 2014
    In:  ECS Meeting Abstracts Vol. MA2014-02, No. 3 ( 2014-08-05), p. 200-200
    Details
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2014-02, No. 3 ( 2014-08-05), p. 200-200
    Abstract: Charge storage behavior in nitride nanomaterials depends on a number of particle properties and also on the nature of the electrode (1-9). Vanadium nitride is a promising supercapacitor material on account of pseudocapacitance arising from the surface oxide/oxynitride phase interactions. We have previously reported excellent charge storage behavior of nanoparticulate vanadium nitride on account of the surface reactions occurring on the surface of the oxide exo-shell. Vanadium oxide is a superior pseudocapacitor material but suffers from poor electronic conductivity(10). Forming a thin surface oxide layer on nanoparticle nitrides yields the benefits of the charge storage along with charge storage occurring in the nitride core itself. However, there is evidence showing that the surface oxide suffers from instability in highly alkaline solutions on account of side-reactions. In addition, the core nitride itself becomes a poor conductor when prepared as fine nanoparticles ( 〈 10 nm)(3). In this study, we tailor nitride nanoparticles to engineer architectures similar to that shown in Figure 1 by the use of suitable dopants. By using wet chemical procedures, we generate a number of doped nitrides with doped surface oxide structure. We use ab-initio first principle studies to guide our dopant selection with improved electronic conductivity of surface oxide/core nitride and stability of surface oxide being parameters driving our dopant selection. We demonstrate in this study doped VN with superior electronic conductivity, high capacity and long cycle life. In-depth surface characterization using XPS and electrochemical impedance spectroscopy (EIS) to probe change in charge-storage mechanisms are conducted herein to obtain fundamental understanding into the nature of the various doped nitride materials. Change in nanoparticle morphology and surface composition are also examined and related to charge storage behavior. Results of these studies will be presented and discussed. References 1. D. Choi, G. E. Blomgren and P. N. Kumta, Advanced Materials , 18 , 1178 (2006). 2. P. Jampani, A. Manivannan and P. N. Kumta, The Electrochemical Society Interface , 19 , 57 (2010). 3. P. J. Hanumantha, M. K. Datta, K. S. Kadakia, D. H. Hong, S. J. Chung, M. C. Tam, J. A. Poston, A. Manivannan and P. N. Kumta, Journal of The Electrochemical Society , 160 , A2195 (2013). 4. D. Choi, Synthesis, Structure and Electrochemical Characterization of Transition Metal Nitride Supercapacitors Derived by a Two-Step Metal Halide Approach, in Materials Science and Engineering , Carnegie Mellon University, Pittsburgh (2005). 5. D. Choi, G. E. Blomgren and P. N. Kumta, Advanced Materials , 18 , 1178 (2006). 6. D. Choi and P. N. Kumta, Journal of the Electrochemical Society , 153 , A2298 (2006). 7. D. Choi and P. N. Kumta, Journal of the American Ceramic Society , 90 , 3113 (2007). 8. D. Choi and P. N. Kumta, Journal of the American Ceramic Society , 94 , 2371 (2011). 9. D. W. Choi and P. N. Kumta, Electrochemical and Solid State Letters , 8 , A418 (2005). 10. P. H. Jampani, K. Kadakia, D. H. Hong, R. Epur, J. A. Poston, A. Manivannan and P. N. Kumta, Journal of The Electrochemical Society , 160 , A1118 (2013).
    Type of Medium: Online Resource
    ISSN: 2151-2043
    URL: Article
    DOI: 10.1149/MA2014-02/3/200
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2014
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Evaluating the Thermodynamics of Electrochemical Ammonia Oxidation for Hydrogen Production
    The Electrochemical Society ; 2014
    In:  ECS Meeting Abstracts Vol. MA2014-01, No. 14 ( 2014-04-01), p. 655-655
    Details
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2014-01, No. 14 ( 2014-04-01), p. 655-655
    Abstract: Objective Electrolysis of ammonia on platinum electrodes is a viable technology for wastewater remediation and hydrogen production[1]. Ammonia is oxidized at the anode, in the presence of hydroxide ions, and water is reduced at the cathode. The only products generated are nitrogen and hydrogen. While the anodic reaction is limited by slow kinetics and catalyst deactivation[2], improvements have been made using bimetallic catalysts[3,4] , especially at low concentrations of ammonia. This improved activity by empirical observation indicated a need for more fundamental analysis through a surface chemistry approach to the electrochemical reaction. This analysis will aid in designing improved catalysts and catalytic compositions. The use of density functional theory for characterizing chemical reactions, especially at the catalyst surface, has yielded valuable insight into the thermodynamics and kinetics of the reactions[5] and this method will be applied for this study. Methodology Density Functional Theory as applied in Gaussian 09[6] was used to generate the electronic and thermodynamic properties of the reactants, products and intermediates of ammonia electro-oxidation. Unrestricted spin calculations (due to unpaired electrons) were performed using the hybrid B3LYP functional[7] while the basis sets used were LANL2DZ[8-11] for platinum atoms and 6-311++G** for nitrogen, oxygen, and hydrogen atoms[12,13] . Using the computational hydrogen electrode[14], the effect of an applied potential was evaluated. Results The aforementioned species present during ammonia electro-oxidation are of the form: NH x (x = 0 – 3), OH y (y = 1 & 2) and N 2 H z (z = 0 – 4) when ammonia electrolysis occurs on platinum below the potential for oxide formation. The adsorption of these species has been previously investigated and characterized using the method above[15,16]. The following trend for adsorption was predicted: N 2 〈 H 2 O 〈 NH 3 〈 N 2 H 2 〈 N 2 H 4 〈 N 2 H 〈 N 2 H 3 〈 OH 〈 NH 2 〈 NH 〈 N . However, these calculations have not accounted for the effect of an applied potential, pH or the solvent environment. Using the method of Norskov et al. ,[14] the effect of these pertubations, which are essential to electrochemical reactions, have been investigated. These results will be presented at the meeting. References [1] F. Vitse, M. Cooper, and G. G. Botte, Journal of Power Sources 142, 18 (2005). [2] H. Gerischer and A. Mauerer, Journal of Electroanalytical Chemistry 25, 421 (1970). [3] E. P. Bonnin, E. J. Biddinger, and G. G. Botte, Journal of Power Sources 182(2008). [4] B. K. Boggs and G. G. Botte, Electrochimica Acta 55(2010). [5] J. Norskov, T. Bligaard, J. Rossmeisl, and C. Christensen, Nature Chemistry 1, 37 (2009). [6] M. J. Frisch et al., Gaussian 09, Revision B.01, Gaussian, Inc., 2009. [7] A. D. Becke, Journal of Chemical Physics 98, 5648 (1993). [8] T. H. Dunning, Journal of Chemical Physics 90, 1007 (1989). [9] P. J. Hay and W. R. Wadt, Journal of Chemical Physics 82, 299 (1985). [10] P. J. Hay and W. R. Wadt, Journal of Chemical Physics 82, 270 (1985). [11] W. R. Wadt and P. J. Hay, Journal of Chemical Physics 82, 284 (1985). [12] G. S. Chandler and A. D. McLean, Journal of Chemical Physics 71, 2175 (1979). [13] A. D. McLean and G. S. Chandler, Journal of Chemical Physics 72, 5639 (1980). [14] J. Norskov, J. Rossmeisl, A. Logadottir, L. Lindqvist, J. Kitchin, T. Bligaard, and H. Jonsson, Journal of Physical Chemistry B 108, 17886 (2004). [15] D. A. Daramola and G. G. Botte, Computational and Theoretical Chemistry 989, 7 (2012). [16] D. A. Daramola and G. G. Botte, Journal of Colloid and Interface Science 402, 204 (2013).
    Type of Medium: Online Resource
    ISSN: 2151-2043
    URL: Article
    DOI: 10.1149/MA2014-01/14/655
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2014
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Voltage Control of Magnetization and Its Chemical Properties
    The Electrochemical Society ; 2014
    In:  ECS Meeting Abstracts Vol. MA2014-02, No. 42 ( 2014-08-05), p. 2040-2040
    Details
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2014-02, No. 42 ( 2014-08-05), p. 2040-2040
    Abstract: Magnetization control using an electric field [1] will be useful because of its expected ultra-low power consumption and coherent behavior. Several experimental approaches to realize it have been done using ferromagnetic semiconductors [2] , materials with magnetostriction together with piezo-driver [3], multiferroic materials [4] , ferromagnetic metal films sintered in a liquid electrolyte [5], and ultra-thin ferromagnetic layer in solid-state junctions[6-8] . One of the critical issues in the electric field switching is a realization of bi-stable switching. Since the electric field does not break time reversal symmetry, it does not remove degeneracy of two magnetic states with opposite magnetization. Therefore, a selection of an arbitral magnetic state is not straightforward [9]. Here, we demonstrate a realization of the bi-stable switching using a coherent precessional magnetization toggle switching in nanoscale magnetic cells with a few atomic FeCo (001) epitaxial layers adjacent to MgO barrier [10] . The control of the magnetization by voltage requires well controlled interface structure. We have investigated chemical states of the ferromagnetic atoms at interface with MgO using XAS and XMCD, and found several problems that may happen at the interfaces in voltage devices, i.e. segregation [11] and voltage controlled reversible oxidization/reduction [12] . We discuss the significance of those effects and the intrinsic effect. References: [1] Curie, P., J. Phys. 3, 393 (1894). [2] Ohno, H. et al., Nature 408, 944-946 (2000), Chiba, D., et al, Science 301, 943-945 (2003). [3] Novosad, V. et al., Journal of Applied Physics 87, 6400-6402 (2000), Lee, J.-W., et al., Applied Physics Letters 82, 2458-2460 (2003). [4] Eerenstein, W., et al., Nature 442, 759-765 (2006), Chu, Y.-H. et al., Nature Materal 7, 478-482 (2008). [5] Weisheit, M. et al., Science 315, 349-351 (2007). [6] Maruyama, T. et al., Nature Nanotechnology 4, 158-161 (2009). [7] M. Endo, et al., Appl. Phys. Lett. 96, 212503 (2010). [8] D. Chiba, et al., Nat. Mat. 10, 853 (2011) . [9] Shiota, Y. et al. Applied Physics Express 2, 063001 (2009). [10] Shiota, Y. et al., Nature Materials, 11, 39-43 (2012). [11] Bonell, F. et al., Surface Science 616, 125-130 (2013). [12] Bonell, F. et al., Appl. Phys. Lett. 102, 152401 (2013).
    Type of Medium: Online Resource
    ISSN: 2151-2043
    URL: Article
    DOI: 10.1149/MA2014-02/42/2040
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2014
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Nanostructure-Driven Ion Transport in PCBM-Based Polymer Electrolytes
    The Electrochemical Society ; 2014
    In:  ECS Meeting Abstracts Vol. MA2014-01, No. 27 ( 2014-04-01), p. 1125-1125
    Details
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2014-01, No. 27 ( 2014-04-01), p. 1125-1125
    Abstract: Polyethylene oxide or PEO is an extensively-examined candidate for solid polymer electrolyte materials of lithium ion batteries, and its composite electrolytes has promising ion conductivities. 1-3 Oxide nanoparticles with sizes of 5-10 nm are often introduced into these polymer-based composite electrolytes in order to suppress their room-temperature crystallite formation. 1-9 The size, geometry and surface functionality of the added particles were known to largely affect the structure and performance of the blended electrolytes. 5,10 In this study, we examined a functionalized-fullerene-based composite electrolytes, providing details in their self-assembled nanostructures, modulus, hardness, as well as temperature-dependent ion-conducting behaviors. To the best of our knowledge, no fullerene-based, lithium conducting, composite electrolyte has been reported previously. Herein we used a bench-mark fullerene derivative, phenyl-C 61 -butyric acid methyl ester (PCBM) as a model fullerene compound and performed impedance spectroscopy, equivalent circuit modeling, nanoscale elemental mapping (in transmission electron microscope), wide-angle X-ray diffraction, as well as nanoindentation to shed light on a 6-fold enhancement in low temperature (less than 50 o C) ion conductivity of PEO - lithium bis(trifluoromethanesulfonyl) imide (LiTFSI)-PCBM electrolytes, along with the underlying changes in nanomorphology , mechanical properties, and crystal structures. Based on a previous density functional theory (DFT) calculation, 11 the interaction energies E i among PEO polymers is estimated to be 2.58 kcal mol -1 per monomer, the E i between PCBM and PEO is 3.50 kcal mol -1 per monomer (PCBM is taken as 1 repeat unit), and the E i among PCBMs themselves is 6.01 kcal mol -1 per monomer. This explains that at very low PCBM weight percentage, without sufficient PCBM-PCBM contacts, it is more energetically favorable for fullerenes to disperse into PEO matrix. However, with higher PCBM concentration, the fullerenes will efficiently pack with each other into domains with gradually increased dimensions. Quantification of PCBM domains is performed by line scan analysis of energy filtered TEM (EFTEM) images. Upon the addition of PCBM, the average domain sizes gradually increase from 3.4±1 nm ( 0% PCBM), to 4.6±1 nm (10% PCBM) and 4.9±2 nm (20% PCBM), and finally to 7.5±5 nm (40% PCBM ). (A precise determination of PCBM domain dimension is not possible when the domain size is less than 3 nm, due to the lack of EFTEM contrast in these samples). We attribute the observed ion conductivity improvement to those nanomorphological variation in PCBM-PEO-LiTFSi systems. (The plot below is obtained from line scan analysis of energy filtered TEM images of PCBM based composite blends as a function of PCBM weight percentage. For each blend, 56 domains in total are analyzed and their domain size distribution is plotted in the graph. ) Reference: 1. Croce, F.; Appetecchi, G. B.; Persi, L.; Scrosati, B., Nature 1998, 394 (6692), 456-458 2. Appetecchi, G. B.; Croce, F.; Hassoun, J.; Scrosati, B.; Salomon, M.; Cassel, F., Hot-pressed, dry, composite, Journal of Power Sources 2003, 114 (1), 105-112; 3. Xiong, H. M.; Zhao, X.; Chen, J. S., Journal of Physical Chemistry B 2001, 105 (42), 10169-10174. 4. Fullerton-Shirey, S. K.; Maranas, J. K., Journal of Physical Chemistry C 2010, 114 (20), 9196-9206 5. Krawiec, W.; Scanlon, L. G.; Fellner, J. P.; Vaia, R. A.; Giannelis, E. P., Journal of Power Sources 1995, 54 (2), 310-315 6. Nan, C. W.; Fan, L. Z.; Lin, Y. H.; Cai, Q., Physical Review Letters 2003, 91 (26) 7. Liu, Y.; Lee, J. Y.; Hong, L., Journal of Applied Polymer Science 2003, 89 (10), 2815-2822 8. Singh, T. J.; Bhat, S. V., Journal of Power Sources 2004, 129 (2), 280-287 9.Chen, H. W.; Chiu, C. Y.; Chang, F. C., Journal of Polymer Science Part B-Polymer Physics 2002, 40 (13), 1342-1353. 10. Dissanayake, M., Ionics 2004, 10 (3-4), 221-225. 11. Chen, J.; Yu, X.; Hong, K.; Messman, J. M.; Pickel, D. L.; Xiao, K.; Dadmun, M. D.; Mays, J. W.; Rondinone, A. J.; Sumpter, B. G.; Kilbey, S. M., II, Journal of Materials Chemistry 2012, 22 (26), 13013-13022. Acknowledgements A portion of this research was conducted at the Center for Nanophase Materials Sciences, which is sponsored at Oak Ridge National Laboratory by the Division of Scientific User Facilities, Office of Basic Energy Sciences, U.S. Department of Energy.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    URL: Article
    DOI: 10.1149/MA2014-01/27/1125
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2014
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Electroless Copper-Based Coating on Lithium Iron Phosphate for Improved Performances
    The Electrochemical Society ; 2014
    In:  ECS Meeting Abstracts Vol. MA2014-02, No. 5 ( 2014-08-05), p. 364-364
    Details
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2014-02, No. 5 ( 2014-08-05), p. 364-364
    Abstract: With Lithium-ion battery production increasing every year, a lot of efforts are involved in research and development of new advanced materials 1 capable of addressing the challenges that arise from the most interesting applications , such as hybrid electric vehicles (HEVs). In this work, the electroless metallization technique has been used to obtain a coating on the surface of active material particles used in the preparation of cathodes and anodes for Li-ion batteries. One of the most promising candidates in the field of energy storage is the olivine-type LiFePO 4 (LFP). This particular material, which was first proposed by Padhi et al. 2 , is characterized by high energy density, low cost and chemical stability. However, this material is presenting a major drawback in its low electronic conductivity due to its intrinsic resistance, and several routes are being investigated to mitigate this issue. Most common approaches are applying a Carbon coating on the surface of LFP 3–5 , reduce particle size 6 and particles doping 7 . In this work, copper-based coating has been applied on LFP particles in order to enhance its electronic conductivity and eventually to increase the resistance to Fe dissolution during cycling, which is recognized as one of the main causes of capacity fading during cycling 8–10 . The coating has been obtained with autocatalytic deposition, with a two-step process: (1) Pd-based particles activation and (2) copper plating through deposition bath containing copper ions and a reducing agent that allows the reduction of metal ions from the solution to the surface of the particles. Positive electrodes have been prepared using PVDF latex as polymeric binder. The resulting cathodes show improved electrical conductivity. Electrochemical characterization has been carried out to assess the nature of the coating and its impact on the performances of the electrode in working conditions. Acknowledgments: This work has been financed with the contribution of the LIFE financial instrument of the European Community. Project n° LIFE12 ENV IT 000712 LIFE+ GLEE. References: 1. B. Scrosati and J. Garche, Journal of Power Sources , 195 , 2419–2430 (2010) 2. A. K. Padhi, K. S. Nanjundaswamy, and J. B. Goodenough, Journal of Electrochemical Society , 144 , 1188–1194 (1997). 3. H. Huang, S.-C. Yin, and L. F. Nazar, Electrochemical and Solid-State Letters , 4 , A170 (2001) 4. K. Amine, J. Liu, and I. Belharouak, Electrochemistry Communications , 7 , 669–673 (2005) 5. C.-K. Park, S.-B. Park, S.-H. Oh, H. Jang, and W.-I. Cho, Bulletin of the Korean Chemical Society , 32 , 836–840 (2011) 6. C. Delacourt, P. Poizot, S. Levasseur, and C. Masquelier, Electrochemical and Solid-State Letters , 9 , A352 (2006) 7. T.-F. Yi et al., Ionics , 18 , 529–539 (2012) 8. W. Porcher, P. Moreau, B. Lestriez, S. Jouanneau, and D. Guyomard, Electrochemical and Solid-State Letters , 11 , A4 (2008) 9. K. Zaghib et al., Journal of Power Sources , 185 , 698–710 (2008) 10. L. Castro et al., Journal of The Electrochemical Society , 159 , A357 (2012)
    Type of Medium: Online Resource
    ISSN: 2151-2043
    URL: Article
    DOI: 10.1149/MA2014-02/5/364
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2014
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Electrochemistry in Molten Oxides: From Electrolyte Design to Oxygen Evolution
    The Electrochemical Society ; 2014
    In:  ECS Meeting Abstracts Vol. MA2014-01, No. 12 ( 2014-04-01), p. 585-585
    Details
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2014-01, No. 12 ( 2014-04-01), p. 585-585
    Abstract: The future carbon-free electricity offers substantial promises for electrochemical engineering, in particular its application to materials processing. As a matter of fact, electricity and electrochemical phenomenon have already significantly contributed to modern metal extraction and manufacturing [1]. More developments are however needed to pursue such trends, in particular for the extraction of metals with limited environmental impact. In that respect, molten oxides electrolytes have a particular appeal identified more than a century ago [2] , thanks to their remarkable chemical stability at a temperature range that allows the production of liquid metal. This presentation offers first to review the intrinsic performances of molten oxides as electrolytic medium, and their corresponding key physicochemical properties. In a second time, the most recent discoveries related to the oxygen evolution reaction in such electrolyte will be presented, in particular with respect to mass transfer limitations [3] and anode materials design [4] . [1] A. Allanore, Journal of Metals - JOM, vol. 65, issue 2, 131, (2013) [2] R. H. Aiken, Process of making iron from the ore. US patent 816, 142 (1906) [3] A. Allanore, Electrochimica Acta, 110, 587-592, (2013) [4] A. Allanore, L. Yin and D.R. Sadoway, Nature, 497 (7449), 353–356, (2013)
    Type of Medium: Online Resource
    ISSN: 2151-2043
    URL: Article
    DOI: 10.1149/MA2014-01/12/585
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2014
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    A Study of Li Based Solid State Battery with Nanoscale Transition Metal Oxide Coatings
    The Electrochemical Society ; 2014
    In:  ECS Meeting Abstracts Vol. MA2014-02, No. 5 ( 2014-08-05), p. 361-361
    Details
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2014-02, No. 5 ( 2014-08-05), p. 361-361
    Abstract: 1. Introduction – Solid state batteries overcome many of the essential drawbacks of liquid electrolyte batteries, such as liquid electrolyte and leakage issues [1]. Another major issue is the degradation of the Li based cathode from continuous cycling due to a change in its microstructure [2] . Nanoscale coatings are thought to prevent the degradation of the cathode by acting as a protective layer on its surface [3, 4]. This paper studies the performance of lithium cobalt oxide (LCO) based cathodes with and without protective coatings of Al 2 O 3 and TiO 2 . 2. Fabrication procedures – Fabrication procedures entail the following stages: (i) Making the liquid lithium lanthanum tantalite (LLTO) electrolyte by a sol gel technique from its precursors and then vaporizing the liquid by exposing it to elevated temperature. The paste left behind is thoroughly dried and finely ground and is included as the solid state electrolyte. (ii) The cathode is made by thoroughly grinding lithium cobalt oxide (LCO) powders and then making slurry by mixing them thoroughly with PTFE binder, carbon powder, and alcohol. Pasted on to a stainless steel foil, this whole system acts as the cathode. (iii) The Atomic Layer Deposition (ALD) technique is used to deposit thin films (~6 nm) on the surface of the LCO cathodes to compare them with the pristine cathodes. (iv) The anode includes Li metal foil. Once this is complete, the three separate components are assembled into a coin cell. 3. Experimental steps and results – The characterization procedures are as follows: (i) XRD and SEM study to check the phase of the solid state LLTO electrolyte, pristine LCO cathode, and cathodes with Al 2 O 3 and TiO 2 coatings and the surface morphology. Figure 1 shows the XRD data of the LCO cathode with TiO 2 deposition. The main Al 2 O 3 peaks are seen and no TiO 2 peaks are obtained, indicating the amorphous nature of the deposition. (ii) TEM and XPS analysis to study the nature and actual thickness of the coating. This will give an idea about the actual depth of the deposition as well as the nature of electronic bonding at the surface. From Figure 3 it may be seen that reduction potential shifts more to the right for the TiO 2 coated cathode. The greater ΔV value exhibited by the coated cathode indicates greater energy needed for the reduction reaction owing to the deposition, and TiO 2 has the highest ΔV value. Figure 2 represents the XPS data of the LCO cathode coated with Al 2 O 3 , showing clearly the Al 2s and 2p and the O 1s peaks. (iii) Cyclic voltammetry is performed within a voltage range of 3 V to 4.5 V and the applied current is 5 mA/s. (iv) Cyclical performance of the cell. Figure 4 shows that open circuit voltages are obtained of slightly less than 3 V for a current density of 10 mA/cm 2 , compared with 3.259 V and 3.312 V, respectively, for i = 30 mA/cm 2 and 40 mA/cm 2 for the LCO pristine cathode. 4. Conclusion – Amorphous transition metal oxide coatings have been tried out. XPS data have shown the formation of the thin film. A rightward shift in the reduction potential demonstrated by the CV data indicates greater energy necessary which is a measure of the protective nature of the coating. Future work includes studies of the cycling performance of the cell with the coated cathodes. References: [1] M.V. Tyufekchiev, S. Hur, Developing a Low-Cost Methodology for Fabricating All-Solid-State Lithium-Ion Battery, in: Chemical Engineering, Worcester Polytechnic Institute, 2013. [2] M. Ogawa, K. Yoshida, K. Harada, Environment, Energy and Resources, 88-90. [3] X. Li, J. Liu, X. Meng, Y. Tang, M.N. Banis, J. Yang, Y. Hu, R. Li, M. Cai, X. Sun, Journal of Power Sources, 247 (2014) 57-69. [4] H. Zhao, L. Gao, W. Qiu, X. Zhang, Journal of Power Sources, 132 (2004) 195-200.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    URL: Article
    DOI: 10.1149/MA2014-02/5/361
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2014
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    First Principles Study of Lithium and Oxygen Adsorption on the β-MnO 2 (110) Surface
    The Electrochemical Society ; 2014
    In:  ECS Meeting Abstracts Vol. MA2014-02, No. 2 ( 2014-08-05), p. 141-141
    Details
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2014-02, No. 2 ( 2014-08-05), p. 141-141
    Abstract: The Li-air system is a novel battery technology which promises higher specific energy than Li-ion batteries. In this battery the cathode reaction is not the formation of an intercalation compound but the reduction of oxygen gas in the presence of Li+ ions forming lithium peroxide Li 2 O 2 (or LiOH in the aqueous version). 1-5 Manganese oxides may also play an important role in this battery: it has been shown that nanostructured MnO 2 in different polymorphic states are able to catalyse the formation and decomposition of Li 2 O 2 in the cathode. Understanding the behaviour of the cathode catalysts is the key for improving the function of Li-air batteries. 6 The adsorption and co-adsorption of lithium and oxygen at the surface of rutile-like manganese dioxide (β-MnO 2 ), which are important in the context of Li-air batteries, are investigated using density functional theory. In the absence of lithium, the most stable surface of β-MnO 2 , the (110), adsorbs oxygen in the form of peroxo groups bridging between two manganese cations. Conversely, in the absence of excess oxygen, lithium atoms adsorb on the (110) surface at two different sites, which are both tri-coordinated to surface oxygen anions, and the adsorption always involves the transfer of one electron from the adatom to one of the five-coordinated manganese cations at the surface, creating (formally) Li + and Mn 3+ species. The co-adsorption of lithium and oxygen leads to the formation of a surface oxide, involving the dissociation of the O 2 molecule, where the O adatoms saturate the coordination of surface Mn cations and also bind to the Li adatoms. This process is energetically more favourable than the formation of gas-phase lithium peroxide (Li 2 O 2 ) monomers, but less favourable than the formation of Li 2 O 2 bulk. These results suggest that the presence of β-MnO 2 in the cathode of a non-aqueous Li-O 2 battery lowers the energy for the initial reduction of oxygen during cell discharge. 1. M. Armand and J. M. Tarascon, Nature, 2008, 451 , 652-657. 2. P. G. Bruce, S. A. Freunberger, L. J. Hardwick and J.-M. Tarascon, Nature materials, 2011, 11 , 19-29. 3. K. Abraham and Z. Jiang, Journal of The Electrochemical Society, 1996, 143 , 1-5. 4. R. Black, B. Adams and L. Nazar, Advanced Energy Materials, 2012, 2 , 801-815. 5. J. Christensen, P. Albertus, R. S. Sanchez-Carrera, T. Lohmann, B. Kozinsky, R. Liedtke, J. Ahmed and A. Kojic, Journal of The Electrochemical Society, 2011, 159 , R1-R30. 6. Y. Shao, S. Park, J. Xiao, J.-G. Zhang, Y. Wang and J. Liu, ACS Catalysis, 2012, 2 , 844-857.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    URL: Article
    DOI: 10.1149/MA2014-02/2/141
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2014
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    A Cyclable Laminar Flow Battery for Large Scale Energy Storage
    The Electrochemical Society ; 2014
    In:  ECS Meeting Abstracts Vol. MA2014-01, No. 4 ( 2014-04-01), p. 386-386
    Details
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2014-01, No. 4 ( 2014-04-01), p. 386-386
    Abstract: Electrochemical systems, such as flow batteries, have the potential to enable cost-effective and environmentally friendly large-scale energy storage [1]. Membraneless laminar flow batteries leverage the laminar flow of co-flowing fluids to prevent reactant crossover [2,3,4] . These latter batteries are a promising class of electrochemical large-scale energy storage systems, as they do not require the use of ion exchange membranes, typically the single most expensive component of the flow battery stack [5]. Further, the power density of flow batteries can be limited by the presence of a membrane. For example, in hydrogen-bromine flow batteries, operating at hydrobromic acid concentration of order 1 M (desirable for high liquid-phase conductivity) can cause the membrane to dehumidify and increase membrane resistivity [6] . Laminar flow batteries can eliminate this issue, but still significant challenges remain in their practical implementation. One major challenge is the demonstration of high efficiency closed-loop cycling (charging and discharging) of laminar flow batteries. This cycling relies on maintaining pure (unmixed) anolyte and catholyte fluid streams to prevent crossover reactions in subsequent cycles. However, the mixing layer necessarily developed between co-flowing fluids in laminar flow batteries prevents the extraction of pure fluid streams downstream of the battery [2,3,7] . To our knowledge, the highest reported number of closed-loop cycles attained in a laminar flow battery is a single cycle at 20% energy efficiency, and with a maximum power of about 0.3 W/cm 2 [8]. We here describe our work in the design and development of a unique prototype laminar flow battery. Unlike previous laminar flow batteries, our device is designed for closed-loop cyclability using innovative means of controlling stream mixing within porous media. This is achieved through two novel mechanisms: i) the use of a porous "dispersion blocker" layer to prevent rapid mixing within the porous structure via transverse mechanical dispersion, and ii) a two-dimensional flow field, including a flow component in the direction of the electric field (in addition to the typical flow which is perpendicular to the electric field), to inhibit oxidant crossover. Through the use of hydrogen-bromine chemistry and flow-through porous electrodes, we demonstrate that our battery can achieve an exceptionally high maximum power density of up to 0.66 W/cm 2 in addition to, for the first time in a laminar flow battery, multiple closed loop cycles. References Skyllas-Kazacos, M., et al. "Progress in flow battery research and development." Journal of The Electrochemical Society 158.8 (2011): R55-R79. Ferrigno, Rosaria, et al. "Membraneless vanadium redox fuel cell using laminar flow." Journal of the American Chemical Society 124.44 (2002): 12930-12931. Kjeang, Erik, Ned Djilali, and David Sinton. "Microfluidic fuel cells: A review." Journal of Power Sources 186.2 (2009): 353-369. Salloum, Kamil S., and Jonathan D. Posner. "Counter flow membraneless microfluidic fuel cell." Journal of Power Sources 195.19 (2010): 6941-6944. Li, L, Kim, S., Xai, W., Wang, W., and Yang, Z., “Advanced Redox Flow Batteries for Stationary Electrical Energy Storage”, U.S. Department of Energy, (2012). Kreutzer, Haley, Venkata Yarlagadda, and Trung Van Nguyen. "Performance Evaluation of a Regenerative Hydrogen-Bromine Fuel Cell." Journal of The Electrochemical Society 159.7 (2012): F331-F337. Braff, William A., Martin Z. Bazant, and Cullen R. Buie. "Membrane-less hydrogen bromine flow battery." Nature communications 4 (2013). Lee, Jin Wook, Marc-Antoni Goulet, and Erik Kjeang. "Microfluidic redox battery." Lab Chip (2013). Figure 1: Schematic of the cyclable laminar flow battery using hydrogen-bromine chemistry. Undesirable bromine (oxidant) flux into the electrolyte channel is prevented through use of a dispersion blocker layer and 2D flow (blue arrows). Insets show numerical results of co-flowing fluids within porous media at high Peclet number, a) without a dispersion blocker layer, and b) with a dispersion blocker. The dispersion blocker can strongly inhibit mixing of co-flowing streams within porous structures of a flow battery.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    URL: Article
    DOI: 10.1149/MA2014-01/4/386
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2014
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    Probing Active Particle Assembly in Lithium-Ion Battery Electrode Processing
    The Electrochemical Society ; 2014
    In:  ECS Meeting Abstracts Vol. MA2014-01, No. 2 ( 2014-04-01), p. 313-313
    Details
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2014-01, No. 2 ( 2014-04-01), p. 313-313
    Abstract: Lithium-ion batteries (LIB) are currently considered as the primary choice for electric drive vehicles. The electrode microstructure and composition play an important role in determining the performance of the LIB. To this end, the processing of the multi-phase slurry consisting of active nanoparticles, conductive additives, binder and solvent determines the electrochemical properties and performance of the electrode. Morphology and the size of the active nanoparticles affect the LIB performance due to large active surface area, short diffusion length and fast kinetics. On the contrary, the aggregation of the active nanoparticles might have a detrimental effect. Therefore, fundamental understanding of the aggregation behavior of the active particles in the slurry is of paramount importance. In this regard, the evaporation dynamics of the slurry is a key factor which determines the microstructural heterogeneity of the electrode. The morphology of the aggregated particles is governed by a variety of physicochemical factors such as interaction between nanoparticles, diffusion rate of the nanoparticles and evaporation rate of the solvent. In this work, we present a mesoscale modeling approach in order to investigate the influence of evaporation on active particle assembly in LIB electrode processing. Our mesoscale model is based on a coarse-grain formalism combining lattice gas and kinetic Monte Carlo methodologies. We will present a comprehensive study of the active particle aggregation behavior and resultant influence due to the (1) evaporation rate of the solvent, (2) active particle and binder interaction, and (3) active particle morphology. Figure 1 shows representative aggregation characteristics of different active particle morphology. Reference J. Li, B. L. Armstrong, J. Kiggans, C. Daniel and D. L. Wood, Langmuir, 28 , 3783-3790 (2012). J. Li, C. Daniel and D. L. Wood, Journal of Power Sources, 196 , 2452-2460 (2011). H. Zheng, R. Yang, G. Liu, X. Song and V. S. Battaglia, Journal of Physical Chemestry C, 116 , 4875-4882 (2012). E. Rabani, D. R. Reichman, P. L. Geissler and L.ha E. Brus, Nature, 426 , 271-274 (2003).
    Type of Medium: Online Resource
    ISSN: 2151-2043
    URL: Article
    DOI: 10.1149/MA2014-01/2/313
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2014
    detail.hit.zdb_id: 2438749-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...