1
|
Kreissl JJA, Petit J, Oppermann R, Cop P, Gerber T, Joos M, Abert M, Tübke J, Miyazaki K, Abe T, Schröder D. Electrochemical Lithiation/Delithiation of ZnO in 3D-Structured Electrodes: Elucidating the Mechanism and the Solid Electrolyte Interphase Formation. ACS Appl Mater Interfaces 2021; 13:35625-35638. [PMID: 34309361 DOI: 10.1021/acsami.1c06135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Conversion/alloy active materials, such as ZnO, are one of the most promising candidates to replace graphite anodes in lithium-ion batteries. Besides a high specific capacity (qZnO = 987 mAh g-1), ZnO offers a high lithium-ion diffusion and fast reaction kinetics, leading to a high-rate capability, which is required for the intended fast charging of battery electric vehicles. However, lithium-ion storage in ZnO is accompanied by the formation of lithium-rich solid electrolyte interphase (SEI) layers, immense volume expansion, and a large voltage hysteresis. Nonetheless, ZnO is appealing as an anode material for lithium-ion batteries and is investigated intensively. Surprisingly, the conclusions reported on the reaction mechanism are contradictory and the formation and composition of the SEI are addressed in only a few works. In this work, we investigate lithiation, delithiation, and SEI formation with ZnO in ether-based electrolytes for the first time reported in the literature. The combination of operando and ex situ experiments (cyclic voltammetry, X-ray photoelectron spectroscopy, X-ray diffraction, coupled gas chromatography and mass spectrometry, differential electrochemical mass spectrometry, and scanning electron microscopy) clarifies the misunderstanding of the reaction mechanism. We evidence that the conversion and alloy reaction take place simultaneously inside the bulk of the electrode. Furthermore, we show that a two-layered SEI is formed on the surface. The SEI is decomposed reversibly upon cycling. In the end, we address the issue of the volume expansion and associated capacity fading by incorporating ZnO into a mesoporous carbon network. This approach reduces the capacity fading and yields cells with a specific capacity of above 500 mAh g-1 after 150 cycles.
Collapse
Affiliation(s)
- Julian J A Kreissl
- Institute of Physical Chemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany
- Center for Materials Research (ZfM), Justus-Liebig-University Giessen, Heinrich-Buff-Ring 16, D-35392 Giessen, Germany
| | - Jan Petit
- Fraunhofer Institute for Chemical Technology ICT, Joseph-von-Fraunhofer-Straße 7, D-76327 Pfinztal, Germany
| | - Raika Oppermann
- Institute of Physical Chemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany
- Center for Materials Research (ZfM), Justus-Liebig-University Giessen, Heinrich-Buff-Ring 16, D-35392 Giessen, Germany
| | - Pascal Cop
- Institute of Physical Chemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany
- Center for Materials Research (ZfM), Justus-Liebig-University Giessen, Heinrich-Buff-Ring 16, D-35392 Giessen, Germany
| | - Tobias Gerber
- Fraunhofer Institute for Chemical Technology ICT, Joseph-von-Fraunhofer-Straße 7, D-76327 Pfinztal, Germany
| | - Martin Joos
- Fraunhofer Institute for Chemical Technology ICT, Joseph-von-Fraunhofer-Straße 7, D-76327 Pfinztal, Germany
| | - Michael Abert
- Fraunhofer Institute for Chemical Technology ICT, Joseph-von-Fraunhofer-Straße 7, D-76327 Pfinztal, Germany
| | - Jens Tübke
- Fraunhofer Institute for Chemical Technology ICT, Joseph-von-Fraunhofer-Straße 7, D-76327 Pfinztal, Germany
| | - Kohei Miyazaki
- Department of Energy & Hydrocarbon Chemistry, Kyoto University, Nishikyo-ku, 615-8510 Kyoto, Japan
| | - Takeshi Abe
- Department of Energy & Hydrocarbon Chemistry, Kyoto University, Nishikyo-ku, 615-8510 Kyoto, Japan
| | - Daniel Schröder
- Institute of Energy and Process Systems Engineering, Technische Universität Braunschweig, Langer Kamp 19B, D-38106 Braunschweig, Germany
| |
Collapse
|
2
|
Oppermann R, Schmidt MJ. Universality class of replica symmetry breaking, scaling behavior, and the low-temperature fixed-point order function of the Sherrington-Kirkpatrick model. Phys Rev E Stat Nonlin Soft Matter Phys 2008; 78:061124. [PMID: 19256819 DOI: 10.1103/physreve.78.061124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Indexed: 05/27/2023]
Abstract
A scaling theory of replica symmetry breaking (RSB) in the Sherrington-Kirkpatrick (SK) model is presented in the framework of critical phenomena for the scaling regime of large RSB orders kappa , small temperatures T , and small (homogeneous) magnetic fields H . We employ the pseudodynamical picture [R. Oppermann, M. J. Schmidt, and D. Sherrington, Phys. Rev. Lett. 98, 127201 (2007)], where two critical points CP1 and CP2 are associated with the order function's pseudodynamical limits lim_{a-->infinity}q(a)=1 and lim_{a-->0}q(a)=0 at (T=0 , H=0 , 1kappa=0) . CP1 - and CP2 -dominated contributions to the free energy functional F[q(a)] require an unconventional scaling hypothesis. We determine the scaling contributions in accordance with detailed numerical self-consistent solutions for up to 200 orders of RSB. Power laws, scaling functions, and crossover lines are obtained. CP1 -dominated behavior is found for the nonequilibrium susceptibility, which decays like chi_{1}=kappa;{-53}f_{1}(Tkappa;{-53}) , for the entropy, which obeys S(T=0) approximately chi_{1};{2} , and for the subclass of diverging parameters a_{i}=kappa;{53}f_{a_{i}}(Tkappa;{-53}) [describing Parisi box sizes m_{i}(T) identical witha_{i}(T)T ], with f_{1}(zeta) approximately zeta and f_{a_{i}}(zeta) approximately 1zeta for zeta-->infinity , while f(0) is finite. CP2 -dominated behavior, controlled by the magnetic field H while temperature is irrelevant, is retrieved in the plateau height (or width) of the order function q(a) according to q_{pl}(H)=kappa;{-1}f_{pl}(H;{23}kappa;{-1}) with f_{pl}mid R:(zeta)mid R:_{zeta-->infinity} approximately zeta and f_{pl}(0) finite. Divergent characteristic RSB orders kappa_{CP1}(T) approximately T;{-35} and kappa_{CP2}(H) approximately H;{-23} , respectively, describe the crossover from mean field SK- to RSB-critical behavior with rational-valued exponents extracted with high precision from our RSB data. The order function q(a) is obtained as a fixed-point function q(a) of RSB flow, in agreement with integrated fixed-point energy and susceptibility distributions.
Collapse
Affiliation(s)
- R Oppermann
- Institut für Theoretische Physik, Universität Würzburg, Am Hubland, 97074 Würzburg, Federal Republic of Germany
| | | |
Collapse
|
3
|
Oppermann R, Schmidt MJ, Sherrington D. Double criticality of the Sherrington-Kirkpatrick model at T=0. Phys Rev Lett 2007; 98:127201. [PMID: 17501152 DOI: 10.1103/physrevlett.98.127201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2006] [Indexed: 05/15/2023]
Abstract
Numerical results up to the 42nd order of replica-symmetry breaking (RSB) are used to predict the singular structure of the Sherrington-Kirkpatrick spin glass at T=0. We confirm predominant single parameter scaling and derive corrections for the T=0 order function q(a), related to a Langevin equation with pseudotime 1/a. a=0 and a=infinity are shown to be two critical points for infinity-RSB, associated with two discrete spectra of Parisi block size ratios, attached to a continuous spectrum. Finite-RSB-size scaling, associated exponents, and T=0-energy are obtained with unprecedented accuracy.
Collapse
Affiliation(s)
- R Oppermann
- Institut für Theoretische Physik, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | | | | |
Collapse
|
4
|
Oppermann R, Sherrington D. Scaling and renormalization group in replica-symmetry-breaking space: evidence for a simple analytical solution of the Sherrington-Kirkpatrick model at zero temperature. Phys Rev Lett 2005; 95:197203. [PMID: 16384018 DOI: 10.1103/physrevlett.95.197203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2005] [Indexed: 05/05/2023]
Abstract
Using numerical self-consistent solutions of a sequence of finite replica symmetry breakings (RSB) and Wilson's renormalization group but with the number of RSB steps playing a role of decimation scales, we report evidence for a nontrivial T-->0 limit of the Parisi order function q(x) for the Sherrington-Kirkpatrick spin glass. Supported by scaling in RSB space, the fixed point order function is conjectured to be q*(a)=sqrt[pi]/2 a/xi erf(xi/a) on 0<or=a<or=infinity, where x/T --> a at T =0 and xi approximately 1.13+/-0.01. Xi plays the role of a correlation length in a-space. q*(a) may be viewed as the solution of an effective 1D field theory.
Collapse
Affiliation(s)
- R Oppermann
- Institut für Theoretische Physik, Universität Würzburg, Am Hubland, 97074 Würzburg, Federal Republic of Germany
| | | |
Collapse
|
7
|
Abstract
We derive a path-integral Schwinger-Keldysh approach for quantum spin systems. This is achieved by means of a semionic representation of spins as fermions with imaginary chemical potential. The major simplifying feature in comparison with other representations (Holstein-Primakoff, Dyson-Maleev, slave bosons/fermions, etc.) is that the local constraint is taken into account exactly. As a result, the standard diagram technique with the usual Feynman codex is constructed. We illustrate the application of this technique for the Néel and spin-liquid states of the antiferromagnetic Heisenberg model.
Collapse
Affiliation(s)
- M N Kiselev
- Institut für Theoretische Physik, Universität Würzburg, D-97074 Würzburg, Germany
| | | |
Collapse
|
10
|
Nakhmedov EP, Kumru M, Oppermann R. Density of states of disordered two-dimensional crystals with half-filled band. Phys Rev Lett 2000; 84:3930-3933. [PMID: 11019242 DOI: 10.1103/physrevlett.84.3930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/1999] [Indexed: 05/23/2023]
Abstract
A diagrammatic method is applied to study the effects of commensurability in two-dimensional disordered crystalline metals by using the particle-hole symmetry with respect to the nesting vector P0 = +/-pi / a,pi / a for a half-filled electronic band. The density of electronic states (DoS) is shown to have nontrivial quantum corrections due to both nesting and elastic impurity scattering processes, and as a result the Van Hove singularity is preserved in the center of the band. However, the energy dependence of the DoS is significantly changed. A small offset from the middle of the band gives rise to the disappearance of quantum corrections to the DoS.
Collapse
Affiliation(s)
- EP Nakhmedov
- Institut fur Theoretische Physik, Universitat Wurzburg, D-97074 Wurzburg, Germany and Institute of Physics, Azerbaijan Academy of Sciences, H. Cavid Street 33, Baku, Azerbaijan
| | | | | |
Collapse
|
11
|
Abstract
The aim of this study was to evaluate the effects of locus of control and work-related stress on burnout in hospital staff nurses. A convenience sample of 361 staff nurses from nine units in five German hospitals were surveyed using the Maslach Burnout Inventory, the Locus of Control Questionnaire and a Work-Related Stress Inventory. Causal modeling was used to explore the moderating effect of locus of control on burnout. Results support the hypothesized model and suggest that greater work-related stress and burnout would be associated with poorer locus of control in nurses. The findings supported the notion that perceived degree of control is instrumental in enabling nurses to cope with stress and burnout.
Collapse
Affiliation(s)
- N Schmitz
- Clinic for Psychosomatic Medicine and Psychotherapy, Heinrich-Heine-University, Bergische Landstr. 2, H19 D-40605, Dusseldorf, Germany.
| | | | | |
Collapse
|