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Gadermaier B, Hogrefe K, Heitjans P, Wilkening HMR. Direct Assessment of Ultralow Li
+
Jump Rates in Single Crystalline Li
3
N by Evolution‐Time‐Resolved
7
Li Spin‐Alignment Echo NMR. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202000941] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Bernhard Gadermaier
- Institute of Chemistry and Technology of Materials Graz University of Technology Stremayrgasse 9 8010 Graz Austria
| | - Katharina Hogrefe
- Institute of Chemistry and Technology of Materials Graz University of Technology Stremayrgasse 9 8010 Graz Austria
| | - Paul Heitjans
- Institute of Physical Chemistry and Electrochemistry Leibniz University Hannover Callinstraße 3–3a 30167 Hannover Germany
| | - H. Martin R. Wilkening
- Institute of Chemistry and Technology of Materials Graz University of Technology Stremayrgasse 9 8010 Graz Austria
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2
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Hogrefe K, Minafra N, Zeier WG, Wilkening HMR. Tracking Ions the Direct Way: Long-Range Li + Dynamics in the Thio-LISICON Family Li 4MCh 4 (M = Sn, Ge; Ch = S, Se) as Probed by 7Li NMR Relaxometry and 7Li Spin-Alignment Echo NMR. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2021; 125:2306-2317. [PMID: 33584937 PMCID: PMC7876753 DOI: 10.1021/acs.jpcc.0c10224] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 01/13/2021] [Indexed: 05/03/2023]
Abstract
Solid electrolytes are key elements for next-generation energy storage systems. To design powerful electrolytes with high ionic conductivity, we need to improve our understanding of the mechanisms that are at the heart of the rapid ion exchange processes in solids. Such an understanding also requires evaluation and testing of methods not routinely used to characterize ion conductors. Here, the ternary Li4MCh4 system (M = Ge, Sn; Ch = Se, S) provides model compounds to study the applicability of 7Li nuclear magnetic resonance (NMR) spin-alignment echo (SAE) spectroscopy to probe slow Li+ exchange processes. Whereas the exact interpretation of conventional spin-lattice relaxation data depends on models, SAE NMR offers a model-independent, direct access to motional correlation rates. Indeed, the jump rates and activation energies deduced from time-domain relaxometry data perfectly agree with results from 7Li SAE NMR. In particular, long-range Li+ diffusion in polycrystalline Li4SnS4 as seen by NMR in a dynamic range covering 6 orders of magnitude is determined by an activation energy of E a = 0.55 eV and a pre-exponential factor of 3 × 1013 s-1. The variation in E a and 1/τ0 is related to the LiCh4 volume that changes within the four Li4MCh4 compounds studied. The corresponding volume of Li4SnS4 seems to be close to optimum for Li+ diffusivity.
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Affiliation(s)
- Katharina Hogrefe
- Institute
of Chemistry and Technology of Materials, Graz University of Technology (NAWI Graz), Stremayrgasse 9, A-8010 Graz, Austria
| | - Nicolò Minafra
- Institute
of Inorganic and Analytical Chemistry, University
of Münster, Correnstrasse
30, D-48149 Münster, Germany
| | - Wolfgang G. Zeier
- Institute
of Inorganic and Analytical Chemistry, University
of Münster, Correnstrasse
30, D-48149 Münster, Germany
| | - H. Martin R. Wilkening
- Institute
of Chemistry and Technology of Materials, Graz University of Technology (NAWI Graz), Stremayrgasse 9, A-8010 Graz, Austria
- Email
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3
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Brinek M, Hiebl C, Hogrefe K, Hanghofer I, Wilkening HMR. Structural Disorder in Li 6PS 5I Speeds 7Li Nuclear Spin Recovery and Slows Down 31P Relaxation-Implications for Translational and Rotational Jumps as Seen by Nuclear Magnetic Resonance. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2020; 124:22934-22940. [PMID: 33193940 PMCID: PMC7662756 DOI: 10.1021/acs.jpcc.0c06090] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 09/18/2020] [Indexed: 06/11/2023]
Abstract
Lithium-thiophosphates have attracted great attention as they offer a rich playground to develop tailor-made solid electrolytes for clean energy storage systems. Here, we used poorly conducting Li6PS5I, which can be converted into a fast ion conductor by high-energy ball-milling to understand the fundamental guidelines that enable the Li+ ions to quickly diffuse through a polarizable but distorted matrix. In stark contrast to well-crystalline Li6PS5I (10-6 S cm-1), the ionic conductivity of its defect-rich nanostructured analog touches almost the mS cm-1 regime. Most likely, this immense enhancement originates from site disorder and polyhedral distortions introduced during mechanical treatment. We used the spin probes 7Li and 31P to monitor nuclear spin relaxation that is directly induced by Li+ translational and/or PS4 3- rotational motions. Compared to the ordered form, 7Li spin-lattice relaxation (SLR) in nano-Li6PS5I reveals an additional ultrafast process that is governed by activation energy as low as 160 meV. Presumably, this new relaxation peak, appearing at T max = 281 K, reflects extremely rapid Li hopping processes with a jump rate in the order of 109 s-1 at T max. Thus, the thiophosphate transforms from a poor electrolyte with island-like local diffusivity to a fast ion conductor with 3D cross-linked diffusion routes enabling long-range transport. On the other hand, the original 31P nuclear magnetic resonance (NMR) SLR rate peak, pointing to an effective 31P-31P spin relaxation source in ordered Li6PS5I, is either absent for the distorted form or shifts toward much higher temperatures. Assuming the 31P NMR peak as being a result of PS4 3- rotational jump processes, NMR unveils that disorder significantly slows down anion dynamics. The latter finding might also have broader implications and sheds light on the vital question how rotational dynamics are to be manipulated to effectively enhance Li+ cation transport.
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Affiliation(s)
- M. Brinek
- Institute for Chemistry and
Technology of Materials, Christian Doppler Laboratory for Lithium
Batteries, Graz University of Technology
(NAWI Graz), Stremayrgasse 9, 8010 Graz, Austria
| | - C. Hiebl
- Institute for Chemistry and
Technology of Materials, Christian Doppler Laboratory for Lithium
Batteries, Graz University of Technology
(NAWI Graz), Stremayrgasse 9, 8010 Graz, Austria
| | - K. Hogrefe
- Institute for Chemistry and
Technology of Materials, Christian Doppler Laboratory for Lithium
Batteries, Graz University of Technology
(NAWI Graz), Stremayrgasse 9, 8010 Graz, Austria
| | - I. Hanghofer
- Institute for Chemistry and
Technology of Materials, Christian Doppler Laboratory for Lithium
Batteries, Graz University of Technology
(NAWI Graz), Stremayrgasse 9, 8010 Graz, Austria
| | - H. M. R. Wilkening
- Institute for Chemistry and
Technology of Materials, Christian Doppler Laboratory for Lithium
Batteries, Graz University of Technology
(NAWI Graz), Stremayrgasse 9, 8010 Graz, Austria
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4
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Volgmann K, Epp V, Langer J, Stanje B, Heine J, Nakhal S, Lerch M, Wilkening M, Heitjans P. Solid-State NMR to Study Translational Li Ion Dynamics in Solids with Low-Dimensional Diffusion Pathways. Z PHYS CHEM 2017. [DOI: 10.1515/zpch-2017-0952] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Fundamental research on lithium ion dynamics in solids is important to develop functional materials for, e.g. sensors or energy storage systems. In many cases a comprehensive understanding is only possible if experimental data are compared with predictions from diffusion models. Nuclear magnetic resonance (NMR), besides other techniques such as mass tracer or conductivity measurements, is known as a versatile tool to investigate ion dynamics. Among the various time-domain NMR techniques, NMR relaxometry, in particular, serves not only to measure diffusion parameters, such as jump rates and activation energies, it is also useful to collect information on the dimensionality of the underlying diffusion process. The latter is possible if both the temperature and, even more important, the frequency dependence of the diffusion-induced relaxation rates of actually polycrystalline materials is analyzed. Here we present some recent systematic relaxometry case studies using model systems that exhibit spatially restricted Li ion diffusion. Whenever possible we compare our results with data from other techniques as well as current relaxation models developed for 2D and 1D diffusion. As an example, 2D ionic motion has been verified for the hexagonal form of LiBH4; in the high-temperature limit the diffusion-induced 7Li NMR spin-lattice relaxation rates follow a logarithmic frequency dependence as is expected from models introduced for 2D diffusion. A similar behavior has been found for Li
x
NbS2. In Li12Si7 a quasi-1D diffusion process seems to be present that is characterized by a square root frequency dependence and a temperature behavior of the 7Li NMR spin-lattice relaxation rates as predicted. Most likely, parts of the Li ions diffuse along the Si5 rings that form chains in the Zintl phase.
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Affiliation(s)
- Kai Volgmann
- Institute of Physical Chemistry and Electrochemistry , Leibniz Universität Hannover , Callinstr. 3 – 3a, D-30167 Hannover , Germany
- ZFM – Center for Solid State Chemistry and New Materials , Leibniz Universität Hannover , Callinstr. 3 – 3a, D-30167 Hannover , Germany
| | - Viktor Epp
- Institute of Physical Chemistry and Electrochemistry , Leibniz Universität Hannover , Callinstr. 3 – 3a, D-30167 Hannover , Germany
- Institute of Chemistry and Technology of Materials, Christian Doppler Laboratory for Lithium Batteries , Graz University of Technology (NAWI Graz) , Stremayrgasse 9 , A-8010 Graz , Austria
| | - Julia Langer
- Institute of Chemistry and Technology of Materials, Christian Doppler Laboratory for Lithium Batteries , Graz University of Technology (NAWI Graz) , Stremayrgasse 9 , A-8010 Graz , Austria
| | - Bernhard Stanje
- Institute of Chemistry and Technology of Materials, Christian Doppler Laboratory for Lithium Batteries , Graz University of Technology (NAWI Graz) , Stremayrgasse 9 , A-8010 Graz , Austria
| | - Jessica Heine
- Institute of Physical Chemistry and Electrochemistry , Leibniz Universität Hannover , Callinstr. 3 – 3a, D-30167 Hannover , Germany
- ZFM – Center for Solid State Chemistry and New Materials , Leibniz Universität Hannover , Callinstr. 3 – 3a, D-30167 Hannover , Germany
| | - Suliman Nakhal
- Institut für Chemie, Sekr. C2 , Technische Universität Berlin , Straße des 17. Juni 135 , D-10623 Berlin , Germany
| | - Martin Lerch
- Institut für Chemie, Sekr. C2 , Technische Universität Berlin , Straße des 17. Juni 135 , D-10623 Berlin , Germany
| | - Martin Wilkening
- Institute of Physical Chemistry and Electrochemistry , Leibniz Universität Hannover , Callinstr. 3 – 3a, D-30167 Hannover , Germany
- Institute of Chemistry and Technology of Materials, Christian Doppler Laboratory for Lithium Batteries , Graz University of Technology (NAWI Graz) , Stremayrgasse 9 , A-8010 Graz , Austria
| | - Paul Heitjans
- Institute of Physical Chemistry and Electrochemistry , Leibniz Universität Hannover , Callinstr. 3 – 3a, D-30167 Hannover , Germany
- ZFM – Center for Solid State Chemistry and New Materials , Leibniz Universität Hannover , Callinstr. 3 – 3a, D-30167 Hannover , Germany
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5
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Sukegawa T, Sato K, Oyaizu K, Nishide H. Efficient charge transport of a radical polyether/SWCNT composite electrode for an organic radical battery with high charge-storage density. RSC Adv 2015. [DOI: 10.1039/c4ra15949g] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
A fast and reversible charge storage capability was established for the radical polyether/SWCNT composite layer with a large layer thickness of several tens of micrometres despite the low SWCNT content of 10%.
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Affiliation(s)
- Takashi Sukegawa
- Department of Applied Chemistry
- Waseda University
- Tokyo 169-8555, Japan
| | - Kan Sato
- Department of Applied Chemistry
- Waseda University
- Tokyo 169-8555, Japan
| | - Kenichi Oyaizu
- Department of Applied Chemistry
- Waseda University
- Tokyo 169-8555, Japan
| | - Hiroyuki Nishide
- Department of Applied Chemistry
- Waseda University
- Tokyo 169-8555, Japan
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6
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Filsø MØ, Turner MJ, Gibbs GV, Adams S, Spackman MA, Iversen BB. Visualizing Lithium-Ion Migration Pathways in Battery Materials. Chemistry 2013; 19:15535-44. [DOI: 10.1002/chem.201301504] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Indexed: 11/07/2022]
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Graf M, Kresse B, Privalov AF, Vogel M. Combining 7Li NMR field-cycling relaxometry and stimulated-echo experiments: a powerful approach to lithium ion dynamics in solid-state electrolytes. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2013; 51-52:25-30. [PMID: 23375382 DOI: 10.1016/j.ssnmr.2013.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 12/05/2012] [Accepted: 01/07/2013] [Indexed: 06/01/2023]
Abstract
We use (7)Li NMR to study lithium ion dynamics in a (Li2S)-(P2S5) glass. In particular, it is shown that a combination of (7)Li field-cycling relaxometry and (7)Li stimulated-echo experiments allows us to cover a time window extending over 10 orders of magnitude without any gaps. While the (7)Li stimulated-echo method proved suitable to measure correlation functions F2(t) of lithium ion dynamics in solids in recent years, we establish the (7)Li field-cycling technique as a versatile tool to ascertain the spectral density J2(ω) of the lithium ionic motion in this contribution. It is found that the dynamic range of (7)Li field-cycling relaxometry is 10(-9)-10(-5)s and, hence, it complements in an ideal way that of (7)Li stimulated-echo experiments, which amounts to 10(-5)-10(1)s. Transformations between time and frequency domains reveal that the field-cycling and stimulated-echo approaches yield results for the translational motion of the lithium ions that are consistent both with each other and with findings for the motional narrowing of (7)Li NMR spectra of the studied (Li2S)-(P2S5) glass. In the (7)Li field-cycling studies of the (Li2S)-(P2S5) glass, we observe the translational ionic motion at higher temperatures and the nearly constant loss at lower temperatures. For the former motion, the frequency dependence of the measured spectral density is well described by a Cole-Davidson function. For the latter phenomenon, which was considered as an universal phenomenon of disordered solids in the literature, we find an exponential temperature dependence.
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Affiliation(s)
- Magnus Graf
- Institut für Festkörperphysik, Technische Universität Darmstadt, Darmstadt, Germany
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Epp V, Gün Ö, Deiseroth HJ, Wilkening M. Long-range Li+ dynamics in the lithium argyrodite Li7PSe6 as probed by rotating-frame spin–lattice relaxation NMR. Phys Chem Chem Phys 2013; 15:7123-32. [DOI: 10.1039/c3cp44379e] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Ruprecht B, Wilkening M, Uecker R, Heitjans P. Extremely slow Li ion dynamics in monoclinic Li2TiO3--probing macroscopic jump diffusion via 7Li NMR stimulated echoes. Phys Chem Chem Phys 2012; 14:11974-80. [PMID: 22836957 DOI: 10.1039/c2cp41662j] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A thorough understanding of ion dynamics in solids, which is a vital topic in modern materials and energy research, requires the investigation of diffusion properties on a preferably large dynamic range by complementary techniques. Here, a polycrystalline sample of Li(2)TiO(3) was used as a model substance to study Li motion by both (7)Li spin-alignment echo (SAE) nuclear magnetic resonance (NMR) and ac-conductivity measurements. Although the two methods do probe Li dynamics in quite different ways, good agreement was found so that the Li diffusion parameters, such as jump rates and the activation energy, could be precisely determined over a dynamic range of approximately eleven decades. For example, Li solid-state diffusion coefficients D(σ) deduced from impedance spectroscopy range from 10(-23) m(2) s(-1) to 10(-12) m(2) s(-1) (240-835 K). These values are in perfect agreement with the coefficients D(SAE) deduced from SAE NMR spectroscopy. As an example, D(SAE) = 2 × 10(-17) m(2) s(-1) at 433 K and the corresponding activation energy determined by NMR amounts to 0.77(2) eV (400-600 K). At room temperature D(σ) takes a value of 3 × 10(-21) m(2) s(-1).
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Affiliation(s)
- Benjamin Ruprecht
- Leibniz University Hannover, Institute of Physical Chemistry and Electrochemistry, ZFM - Center for Solid State Chemistry and New Materials, Callinstr. 3a, 30167 Hannover, Germany
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10
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Kuhn A, Epp V, Schmidt G, Narayanan S, Thangadurai V, Wilkening M. Spin-alignment echo NMR: probing Li+ hopping motion in the solid electrolyte Li7La3Zr2O12 with garnet-type tetragonal structure. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:035901. [PMID: 22179497 DOI: 10.1088/0953-8984/24/3/035901] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
(7)Li spin-alignment echo (SAE) nuclear magnetic resonance (NMR) spectroscopy has been used to measure single-spin hopping correlation functions of polycrystalline Li(7)La(3)Zr(2)O(12). Damping of the echo amplitude S(2)(t(m),t(p)), recorded at variable mixing time t(m) but fixed preparation time t(p), turns out to be solely controlled by slow Li jump processes taking place in the garnet-like structure. The decay rates τ(SAE)(-1) directly obtained by parametrizing the curves S(2)(t(m),t(p)) with stretched exponential functions show Arrhenius behaviour pointing to an activation energy of approximately 0.5 eV. This value, probed by employing an atomic-scale NMR method, is in very good agreement with that deduced from impedance spectroscopy used to measure macroscopic Li transport parameters. Most likely, the two methods are sensitive to the same hopping correlation function although Li dynamics are probed in a quite different manner.
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Affiliation(s)
- A Kuhn
- Institute of Physical Chemistry and Electrochemistry, Gottfried Wilhlem Leibniz University Hannover, Hannover, Germany
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11
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Welsch AM, Behrens H, Horn I, Roß S, Heitjans P. Self-Diffusion of Lithium in LiAlSi2O6 Glasses Studied Using Mass Spectrometry. J Phys Chem A 2011; 116:309-18. [DOI: 10.1021/jp209319b] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- A.-M. Welsch
- Institut für Mineralogie, ‡ZFM - Zentrum für Festkörperchemie und Neue Materialien, and §Institut für Physikalische Chemie und Elektrochemie, Leibniz Universität Hannover, Hannover, Germany D-30167
| | - H. Behrens
- Institut für Mineralogie, ‡ZFM - Zentrum für Festkörperchemie und Neue Materialien, and §Institut für Physikalische Chemie und Elektrochemie, Leibniz Universität Hannover, Hannover, Germany D-30167
| | - I. Horn
- Institut für Mineralogie, ‡ZFM - Zentrum für Festkörperchemie und Neue Materialien, and §Institut für Physikalische Chemie und Elektrochemie, Leibniz Universität Hannover, Hannover, Germany D-30167
| | - S. Roß
- Institut für Mineralogie, ‡ZFM - Zentrum für Festkörperchemie und Neue Materialien, and §Institut für Physikalische Chemie und Elektrochemie, Leibniz Universität Hannover, Hannover, Germany D-30167
| | - P. Heitjans
- Institut für Mineralogie, ‡ZFM - Zentrum für Festkörperchemie und Neue Materialien, and §Institut für Physikalische Chemie und Elektrochemie, Leibniz Universität Hannover, Hannover, Germany D-30167
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12
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Wilkening M, Heitjans P. From Micro to Macro: Access to Long-Range Li+ Diffusion Parameters in Solids via Microscopic 6, 7Li Spin-Alignment Echo NMR Spectroscopy. Chemphyschem 2011; 13:53-65. [DOI: 10.1002/cphc.201100580] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Indexed: 11/06/2022]
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13
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Buschmann H, Dölle J, Berendts S, Kuhn A, Bottke P, Wilkening M, Heitjans P, Senyshyn A, Ehrenberg H, Lotnyk A, Duppel V, Kienle L, Janek J. Structure and dynamics of the fast lithium ion conductor “Li7La3Zr2O12”. Phys Chem Chem Phys 2011; 13:19378-92. [DOI: 10.1039/c1cp22108f] [Citation(s) in RCA: 457] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Ruprecht B, Billetter H, Ruschewitz U, Wilkening M. Ultra-slow Li ion dynamics in Li(2)C(2)--on the similarities of results from (7)Li spin-alignment echo NMR and impedance spectroscopy. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:245901. [PMID: 21393791 DOI: 10.1088/0953-8984/22/24/245901] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Li diffusion and transport parameters of binary lithium carbide Li(2)C(2) were complementarily investigated by (7)Li (nuclear magnetic resonance) NMR and impedance spectroscopy. Long-range Li diffusion parameters were measured by using mixing-time-dependent and temperature-variable stimulated echo NMR spectroscopy. The method is sensitive to ultra-slow Li hopping processes which were probed from an atomic-scale point of view. Two-time phase correlation functions S(2) obtained can be parameterized by stretched exponentials only. The corresponding echo decay rates τ(-1), which were recorded at a resonance frequency of e.g. 155.5 MHz, show Arrhenius behaviour revealing an activation energy of 0.80(2) eV. This value is in very good agreement with that deduced from dc conductivity measurements (0.79(2) eV) probing Li transport processes on a macroscopic length scale. The comparison of impedance data with the measured NMR echo decay functions showed that both methods reflect diffusion processes being characterized by very similar motional correlation functions.
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Affiliation(s)
- B Ruprecht
- Institute of Physical Chemistry and Electrochemistry, Leibniz University Hannover, Callinstraße 3a, D-30167 Hannover, Germany
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15
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Düvel A, Wilkening M, Uecker R, Wegner S, Šepelák V, Heitjans P. Mechanosynthesized nanocrystalline BaLiF3: The impact of grain boundaries and structural disorder on ionic transport. Phys Chem Chem Phys 2010; 12:11251-62. [DOI: 10.1039/c004530f] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Wilkening M, Heitjans P. Li transport in crystalline and glassy ion conductors as microscopically probed by 6,7Li stimulated echo NMR. Z Anorg Allg Chem 2008. [DOI: 10.1002/zaac.200870021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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17
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Koch B, Vogel M. Lithium ionic jump motion in the fast solid ion conductor Li(5)La(3)Nb(2)O(12). SOLID STATE NUCLEAR MAGNETIC RESONANCE 2008; 34:37-43. [PMID: 18406110 DOI: 10.1016/j.ssnmr.2008.03.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2008] [Indexed: 05/26/2023]
Abstract
Using (7)Li NMR line-shape analysis, spin-lattice relaxation measurements and stimulated-echo spectroscopy, we investigate the lithium ionic jump motion in the garnet Li(5)La(3)Nb(2)O(12). Results for two samples are compared, which were annealed at 850( composite function)C (GR-850) and at 900( composite function)C (GR-900), respectively. All (7)Li NMR data consistently show that two lithium species with distinguishable dynamical behaviors coexist in each of the samples. While the less mobile species is the majority component in GR-850, the more mobile species is the majority component in GR-900. (7)Li NMR stimulated-echo spectroscopy provides straightforward access to the correlation functions describing the jumps of the respective majority component in both samples. From the temperature-dependent correlation times, we obtain activation energies of 56 and 32kJmol(-1) for GR-850 and GR-900, respectively. For both samples, the correlation functions substantially deviate from simple exponential behavior, indicating a high complexity of the lithium ionic motion in Li(5)La(3)Nb(2)O(12).
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Affiliation(s)
- Barbara Koch
- Institut fur Physikaleische Chemie, Westfalische Wilhelms-Universitat Munster, Munster, Germany
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18
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Wilkening M, Iwaniak W, Heine J, Epp V, Kleinert A, Behrens M, Nuspl G, Bensch W, Heitjans P. Microscopic Li self-diffusion parameters in the lithiated anode material Li4+xTi5O12 (0 ≤x≤ 3) measured by 7Li solid state NMR. Phys Chem Chem Phys 2007; 9:6199-202. [DOI: 10.1039/b713311a] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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