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Synergistic regulation of garnet-type Ta-doped Li7La3Zr2O12 solid electrolyte by Li+ concentration and Li+ transport channel size. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2018.11.136] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Hayamizu K, Seki S, Haishi T. Lithium ion micrometer diffusion in a garnet-type cubic Li7La3Zr2O12(LLZO) studied using7Li NMR spectroscopy. J Chem Phys 2017; 146:024701. [DOI: 10.1063/1.4973827] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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Pinzaru D, Thangadurai V. Evaluation on the effect of gadolinium-doping for niobium on the morphology and ionic conductivity of garnet-like Li5La3Nb2O12. CAN J CHEM 2016. [DOI: 10.1139/cjc-2015-0268] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
There is a great interest in gaining a deeper understanding of the lithium ion conductivity of Li-stuffed garnets that result from the substitution at either the La or M sites in Li5La3M2O12 (M = Nb, Ta), since these materials can be used as potential electrolytes in all solid-state batteries. Here, we investigate the effect of replacing Nb5+ with Gd3+ and stuffing two Li+ per Gd3+ in Li5La3Nb2O12 on the structure and ionic conductivity of the new family of garnet-type compounds with the nominal formula Li5+2xLa3Nb2−xGdxO12 (0 ≤ x ≤ 0.45). The samples were prepared via conventional solid-state synthesis in air at elevated temperatures. Powder X-ray diffraction studies confirmed the formation of the garnet-type structure for Li5+2xLa3Nb2−xGdxO12 (0 ≤ x ≤ 0.45). Elemental mapping obtained using energy dispersive X-ray analysis showed no evidence of a secondary phase being formed in Li5+2xLa3Nb2−xGdxO12 (0 ≤ x ≤ 0.45). Archimedes’ density measurements confirmed that the density of the samples with x ≤ 0.25 is not improved. The porosity of the samples with x ≥ 0.3 was found to be in the 8%–16% range. Among the samples investigated in this work, the x = 0.45 member of Li5+2xLa3Nb2−xGdxO12 showed the highest ionic conductivity of 1.91 × 10−5 S cm−1 at room temperature, which is an order of magnitude higher than that of the parent compound Li5La3Nb2O12. The activation energy of this material was calculated to be 0.38 eV at 25–225 °C and 0.28 eV at 225–325 °C. The change in the activation energy at the high temperature regime can be explained using the Li site occupation model in the garnet-type structure.
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Affiliation(s)
- Dana Pinzaru
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
| | - Venkataraman Thangadurai
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
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Zeier WG. Structural limitations for optimizing garnet-type solid electrolytes: a perspective. Dalton Trans 2015; 43:16133-8. [PMID: 25277079 DOI: 10.1039/c4dt02162b] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Lithium ion batteries exhibit the highest energy densities of all battery types and are therefore an important technology for energy storage in every day life. Today's commercially available batteries employ organic polymer lithium conducting electrolytes, leading to multiple challenges and safety issues such as poor chemical stability, leakage and flammability. The next generation lithium ion batteries, namely all solid-state batteries, can overcome these limitations through employing a ceramic Li(+) conducting electrolyte. In the past decade, there has been a major focus on the structural and ionic transport properties of lithium-conducting garnets, and the extensive research efforts have led to a thorough understanding of the structure-property relationships in this class of materials. However, further improvement seems difficult due to structural limitations. The purpose of this Perspective article is to provide a brief structural overview of Li conducting garnets and the structural influence on the optimization of Li-ionic conductivities.
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Affiliation(s)
- Wolfgang G Zeier
- Department of Applied Physics and Material Science, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125, USA.
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Baral AK, Narayanan S, Ramezanipour F, Thangadurai V. Evaluation of fundamental transport properties of Li-excess garnet-type Li5+2xLa3Ta2−xYxO12 (x = 0.25, 0.5 and 0.75) electrolytes using AC impedance and dielectric spectroscopy. Phys Chem Chem Phys 2014; 16:11356-65. [DOI: 10.1039/c4cp00418c] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Thangadurai V, Narayanan S, Pinzaru D. Garnet-type solid-state fast Li ion conductors for Li batteries: critical review. Chem Soc Rev 2014; 43:4714-27. [DOI: 10.1039/c4cs00020j] [Citation(s) in RCA: 992] [Impact Index Per Article: 99.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Bottke P, Ren Y, Hanzu I, Bruce PG, Wilkening M. Li ion dynamics in TiO2anode materials with an ordered hierarchical pore structure – insights from ex situ NMR. Phys Chem Chem Phys 2014; 16:1894-901. [DOI: 10.1039/c3cp54586e] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ramakumar S, Satyanarayana L, Manorama SV, Murugan R. Structure and Li+ dynamics of Sb-doped Li7La3Zr2O12 fast lithium ion conductors. Phys Chem Chem Phys 2013; 15:11327-38. [PMID: 23732926 DOI: 10.1039/c3cp50991e] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Antimony-doped lithium stuffed garnets Li(7-x)La3Zr(2-x)Sb(x)O12 (x = 0.2-1.0) prepared using a conventional solid state reaction method are characterized using Powder X-ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Energy Dispersive Analysis by X-ray (EDAX), AC Impedance spectroscopy, Magic Angle Spinning Nuclear Magnetic Resonance (MAS NMR) and Raman spectroscopic techniques. PXRD confirms the formation of a garnet-like structure with cubic symmetry for the entire selected compositional range. Among the investigated compounds, the compound with an Sb content corresponding to x = 0.4, i.e. Li6.6La3Zr1.6Sb0.4O12 exhibits the maximum total (bulk + grain boundary) ionic conductivity of 7.7 × 10(-4) S cm(-1) at 30 °C. The shape of the imaginary part of the modulus spectra suggests that the relaxation processes are non-Debye in nature. The full width at half maximum (FWHM) for the master modulus curve of Li6.6La3Zr1.6Sb0.4O12 is found to be the smallest among the investigated lithium garnets. The full width at half maximum (FWHM) of the (7)Li MAS NMR spectrum for the composition Li6.6La3Zr1.6Sb0.4O12 is the smallest among the investigated compounds. Raman data collected for the compounds in this series indicates an increase of Li(+) occupancy in the tetrahedrally coordinated site with an associated decrease of Li(+) occupancy in the octahedrally coordinated site during an increase of x in Li(7-x)La3Zr(2-x)Sb(x)O12. The present investigation reveals that the optimal Li(+) concentration required to achieve the maximum room-temperature Li(+) conductivity in Li(7-x)La3Zr(2-x)Sb(x)O12 lithium stuffed garnet is around x = 0.4.
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Affiliation(s)
- S Ramakumar
- Department of Physics, Pondicherry University, Puducherry 605 014, India
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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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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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Kuhn A, Choi JY, Robben L, Tietz F, Wilkening M, Heitjans P. Li Ion Dynamics in Al-Doped Garnet-Type Li7La3Zr2O12 Crystallizing with Cubic Symmetry. ACTA ACUST UNITED AC 2012. [DOI: 10.1524/zpch.2012.0250] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Lithium-ion dynamics in the garnet-type solid electrolyte “Li7La3Zr2O12” (LLZ) crystallizing with cubic symmetry was probed by means of variable-temperature 7Li NMR spectroscopy and ac impedance measurements. Li jump rates of an Al-containing sample follow Arrhenius behaviour being characterized by a relatively high activation energy of 0.54(3) eV and a pre-exponential factor of 2.2(5) × 10
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s-1. The results resemble those which were quite recently obtained for an Al-free LLZ sample crystallizing, however, with tetragonal symmetry. Hence, most likely, the significantly higher Li conductivity previously reported for a cubic LLZ sample cannot be ascribed solely to the slight structural distortions accompanying the change of the crystal symmetry. Here, even Al impurities, acting as stabilizer for the cubic polymorph at room temperature, do not lead to the high ion conductivity reported previously.
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Affiliation(s)
| | - Joon-Yong Choi
- Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research, Jülich, Deutschland
| | - Lars Robben
- Leibniz Universität Hannover, Institute of Mineralogy, Hannover, Deutschland
| | - Frank Tietz
- Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research, Jülich, Deutschland
| | - Martin Wilkening
- Leibniz University Hannover, Institute of Phys. Chemistry and Electrochemistry, Hannover, Deutschland
| | - Paul Heitjans
- Universität Hannover, Institut f. Physikalische Chemie und Elektrochemie, Hannover, Deutschland
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Epp V, Brünig C, Binnewies M, Heitjans P, Wilkening M. Studying Li Dynamics in a Gas-Phase Synthesized Amorphous Oxide by NMR and Impedance Spectroscopy. Z PHYS CHEM 2012. [DOI: 10.1524/zpch.2012.0224] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Li diffusion parameters of a structurally disordered Li-Al-Si-oxide prepared by gas-phase synthesis were complementarily investigated by both time-domain NMR techniques and impedance spectroscopy. The first include 7Li NMR spin-lattice relaxation (SLR) measurements in the laboratory as well as in the rotating frame of reference. An analysis of variable-temperature NMR line widths point to an activation energy Ea
of approximately 0.6 eV. The value is confirmed by rotating-frame SLR NMR data recorded at approximately 11 kHz. Above room temperature the low-temperature flank of a diffusion-induced rate peak shows up which can be approximated by an Arrhenius law yielding Ea=0.56(1) eV. This is in very good agreement with the result obtained from 7Li spin-alignment echo (SAE) NMR being sensitive to even slower Li dynamics. For comparison, dc-conductivity measurements, probing long-range motions, yield Ea=0.8 eV. Interestingly, low-temperature SAE NMR decay rates point to localized Li motions being characterized with a very small activation energy of only 0.09 eV.
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Affiliation(s)
| | - Christian Brünig
- Leibniz University Hannover, Institute of Inorganic Chemistry, Hannover, Deutschland
| | - Michael Binnewies
- Leibniz University of Hannover, Institute of Inorganic Chemistry, Hannover, Deutschland
| | - Paul Heitjans
- Universität Hannover, Institut f. Physikalische Chemie und Elektrochemie, Hannover, Deutschland
| | - Martin Wilkening
- Leibniz University Hannover, Institute of Phys. Chemistry and Electrochemistry, Hannover, Deutschland
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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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Howard MA, Clemens O, Kendrick E, Knight KS, Apperley DC, Anderson PA, Slater PR. Effect of Ga incorporation on the structure and Li ion conductivity of La3Zr2Li7O12. Dalton Trans 2012; 41:12048-53. [DOI: 10.1039/c2dt31318a] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Narayanan S, Epp V, Wilkening M, Thangadurai V. Macroscopic and microscopic Li+ transport parameters in cubic garnet-type “Li6.5La2.5Ba0.5ZrTaO12” as probed by impedance spectroscopy and NMR. RSC Adv 2012. [DOI: 10.1039/c2ra01042a] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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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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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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Geiger CA, Alekseev E, Lazic B, Fisch M, Armbruster T, Langner R, Fechtelkord M, Kim N, Pettke T, Weppner W. Crystal Chemistry and Stability of “Li7La3Zr2O12” Garnet: A Fast Lithium-Ion Conductor. Inorg Chem 2010; 50:1089-97. [DOI: 10.1021/ic101914e] [Citation(s) in RCA: 492] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Charles A. Geiger
- Institut für Geowissenschaften, Abteilung Mineralogie, Christian-Albrechts-Universität zu Kiel, D-24118 Kiel, Germany
| | - Evgeny Alekseev
- Institut für Geowissenschaften, Abteilung Mineralogie, Christian-Albrechts-Universität zu Kiel, D-24118 Kiel, Germany
| | - Biljana Lazic
- Mineralogische Kristallographie, Institut für Geologie, Universität Bern, CH-3012 Bern, Switzerland
| | - Martin Fisch
- Mineralogische Kristallographie, Institut für Geologie, Universität Bern, CH-3012 Bern, Switzerland
| | - Thomas Armbruster
- Mineralogische Kristallographie, Institut für Geologie, Universität Bern, CH-3012 Bern, Switzerland
| | - Ramona Langner
- Institut für Geologie, Mineralogie und Geophysik, Ruhr-Universität Bochum, D-44780 Bochum, Germany
| | - Michael Fechtelkord
- Institut für Geologie, Mineralogie und Geophysik, Ruhr-Universität Bochum, D-44780 Bochum, Germany
| | - Namjun Kim
- Department of Geological and Environmental Sciences, Stanford University, Stanford, California 94305-2115, United States
| | - Thomas Pettke
- Mineralogische Kristallographie, Institut für Geologie, Universität Bern, CH-3012 Bern, Switzerland
| | - Werner Weppner
- Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel, Otto-Hahn-Platz 6-7, D-24118 Kiel, Germany
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Brinkmann C, Faske S, Koch B, Vogel M. NMR Multi-Time Correlation Functions of Ion Dynamics in Solids. ACTA ACUST UNITED AC 2010. [DOI: 10.1524/zpch.2010.0014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
We show that NMR multi-time correlation functions provide interesting new insights into the nature of lithium and silver ion dynamics in solids. For solid ion conductors, they usually probe the elementary jumps of the long-range charge transport. NMR two-time correlation functions yield rates and activation energies of the ionic hopping motion. Moreover, they reveal that the ionic relaxation exhibits a strong nonexponentiality in the studied crystals and glasses. NMR three-time correlation functions enable quantitative determination of the origin of the nonexponentiality. For various solid-state electrolytes, the analysis shows that pronounced dynamical heterogeneities govern the ionic hopping motion. If dynamical heterogeneities exist, NMR four-time correlation functions allow one to measure the time scale of exchange processes within the rate distributions. For silver ion dynamics in a crystalline and a glassy material, the results indicate that initially slow ions exhibit random new rates from broad rate distributions after very few jump events.
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Affiliation(s)
- Christian Brinkmann
- Westfälische Wilhelms-Universität Münster, Institut für Physikalische Chemie, Münster
| | - Sandra Faske
- Westfälische Wilhelms-Universität Münster, Institut für Physikalische Chemie, Münster
| | - Barbara Koch
- Westfälische Wilhelms-Universität Münster, Institut für Physikalische Chemie, Münster
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Ramzy A, Thangadurai V. Tailor-made development of fast Li ion conducting garnet-like solid electrolytes. ACS APPLIED MATERIALS & INTERFACES 2010; 2:385-90. [PMID: 20356183 DOI: 10.1021/am900643t] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
This paper reports a novel approach to designing advanced solid Li ion electrolytes for application in various solid state ionic devices, including Li ion secondary batteries, gas sensors, and electrochromic displays. The employed methodology involves a solid-solution reaction between the two best-known fast Li ion conductors in the garnet-family of compounds Li(6)BaLa(2)M(2)O(12) (M = Nb, Ta) and Li(7)La(3)Zr(2)O(12). Powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), AC impedance, and (7)Li nuclear magnetic resonance (Li NMR) spectroscopy were employed to characterize phase formation, morphology, ionic conductivity, and Li ion coordination in Li(6.5)La(2.5)BaZrMO(12). PXRD shows for formation of a cubic garnet-like structure and AC impedance data is consistent with other known solid Li ion electrolytes. Li(6.5)La(2.5)BaZrTaO(12) exhibits a fast Li ion conductivity of about 6 x 10(-3) S cm(-1) at 100 degrees C, which is comparable to that of currently employed organic polymer electrolytes value at room temperature. The Nb analogue shows an order of magnitude lower ionic conductivity than that of the corresponding Ta member, which is consistent with the trend in garnet-type electrolytes reported in the literature. Samples sintered at 1100 degrees C shows the highest electrical conductivity compared to that of 900 degrees C. (7)Li MAS NMR shows a sharp single peak at 0 ppm with respect to LiCl, which may be attributed to fast migration of ions between various sites in the garnets, and also suggesting average distributions of Li ions at average octahedral coordination in Li(6.5)La(2.5)BaZrMO(12). The present work together with literature used to establish very important fundamental relationship of functional property-Li concentration-crystal structure-Li diffusion coefficient in the garnet family of Li ion electrolytes.
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Affiliation(s)
- Adam Ramzy
- Department of Chemistry, The University of Calgary, Calgary, Alberta T2N 1N4, Canada
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Percival J, Kendrick E, Smith RI, Slater PR. Cation ordering in Li containing garnets: synthesis and structural characterisation of the tetragonal system, Li7La3Sn2O12. Dalton Trans 2009:5177-81. [DOI: 10.1039/b907331k] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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