1
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Kumar R, Zhu Q. Dynamic density functional theory of polymers with salt in electric fields. J Chem Phys 2024; 161:104902. [PMID: 39254960 DOI: 10.1063/5.0222997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Accepted: 08/22/2024] [Indexed: 09/11/2024] Open
Abstract
We present a dynamic density functional theory for modeling the effects of applied electric fields on the local structure of polymers with added salt (polymer electrolytes). Time-dependent equations for the local electrostatic potential and volume fractions of polymer, cation, and anion of added salt are developed using the principles of linear irreversible thermodynamics. For such a development, a field theoretic description of the free energy of polymer melts doped with salts is used, which captures the effects of local variations in the dielectric function. Connections of the dynamic density functional theory with experiments are established by relating the three phenomenological Onsager's transport coefficients of the theory to the mutual diffusion of electrolyte, ionic conductivity, and transference number of one of the ions. The theory is connected with a statistical mechanical model developed by Bearman and Kirkwood [J. Chem. Phys. 28, 136 (1958)] after relating the three transport coefficients to friction coefficients. The steady-state limit of the dynamic density functional theory is used to understand the effects of dielectric inhomogeneity on the phase separation in polymer electrolytes. The theory developed here provides not only a way to connect with experiments but also to develop multi-scale models for studying connections between local structure and ion transport in polymer electrolytes.
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Affiliation(s)
- Rajeev Kumar
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Qinyu Zhu
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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2
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Rajahmundry GK, Patra TK. Understanding Ion Distribution and Diffusion in Solid Polymer Electrolytes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:18942-18949. [PMID: 39185775 DOI: 10.1021/acs.langmuir.4c01543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Solid polymer electrolytes (SPEs)─polymer melts with added salts─exhibit ion conduction and high mechanical properties, and are thus promising materials for future energy storage devices. The ion conductivity in an SPE is intricately connected to the salt ion distribution in the polymer matrix. The relationship between ion diffusion and ion distribution in SPEs remains unresolved. Here, we conduct coarse-grained molecular dynamics simulations and establish correlations between ion distribution and transport for a phenomenological SPE model. We propose phase diagrams of SPEs as a function of ion pair size, ion concentration, and the Bjerrum length of the material. A crossover from a discrete ion aggregate to a percolated ion aggregate is demonstrated as a function of ion pair size for low ion concentration in the SPE. The ion diffusion shows a strong correlation with its size, as has been found experimentally. The work provides important design strategies for controlling the ion distribution and enhancing ion conductivity in a polymer matrix.
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Affiliation(s)
- Ganesh K Rajahmundry
- Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai 600036, India
| | - Tarak K Patra
- Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai 600036, India
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3
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Carrillo-Bohórquez O, Kuroda DG, Kumar R. A transferable classical force field to describe glyme based lithium solvate ionic liquids. J Chem Phys 2024; 161:054504. [PMID: 39092940 DOI: 10.1063/5.0214769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Accepted: 07/14/2024] [Indexed: 08/04/2024] Open
Abstract
A non-polarizable force field for lithium (Li+) and bis(trifluoromethanesulfonyl)imide (TFSI-) ions solvated in diglyme at around 0.2 mol fraction salt concentration was developed based on ab initio molecular dynamics (AIMD) simulations and a modified polymer consistent force field model. A force-torque matching based scheme, in conjunction with a genetic algorithm, was used to determine the Lennard-Jones (LJ) parameters of the ion-ion and ion-solvent interactions. This force field includes a partial charge scaling factor and a scaling factor for the 1-4 interactions. The resulting force field successfully reproduces the radial distribution function of the AIMD simulations and shows better agreement compared to the unmodified force field. The new force field was then used to simulate salt solutions with glymes of increasing chain lengths and different salt concentrations. The comparison of the MD simulations, using the new force field, with experimental data at different salt concentrations and AIMD simulations on equimolar concentrations of the triglyme system demonstrates the transferability of the force field parameters to longer glymes and higher salt concentrations. Furthermore, the force field appears to reproduce the features of the experimental x-ray structure factors, suggesting accuracy beyond the first solvation shell, for equimolar salt solutions using both triglyme and tetraglyme as the solvent. Overall, the new force field was found to accurately reproduce the molecular descriptions of LiTFSI-glyme systems not only at various salt concentrations but also with glymes of different chain lengths. Thus, the new force field provides a useful and accurate tool to perform in silico studies of this family of systems at the atomistic level.
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Affiliation(s)
- Orlando Carrillo-Bohórquez
- Department of Chemistry, Louisiana State University, 232 Choppin Hall, Baton Rouge, Louisiana 70803, USA
| | - Daniel G Kuroda
- Department of Chemistry, Louisiana State University, 232 Choppin Hall, Baton Rouge, Louisiana 70803, USA
| | - Revati Kumar
- Department of Chemistry, Louisiana State University, 232 Choppin Hall, Baton Rouge, Louisiana 70803, USA
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4
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Tsamopoulos A, Wang ZG. Ion Conductivity in Salt-Doped Polymers: Combined Effects of Temperature and Salt Concentration. ACS Macro Lett 2024; 13:322-327. [PMID: 38395049 PMCID: PMC10956493 DOI: 10.1021/acsmacrolett.3c00757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/19/2024] [Accepted: 02/21/2024] [Indexed: 02/25/2024]
Abstract
We construct a coarse-grained molecular dynamics model based on poly(ethylene oxide) and lithium bis(trifluoromethane)sulfonimide salt to examine the combined effects of temperature and salt concentration on the transport properties. Salt doping notably slows the dynamics of polymer chains and reduces ion diffusivity, resulting in a glass transition temperature increase proportional to the salt concentration. The polymer diffusion is shown to be well represented by a modified Vogel-Fulcher-Tamman (M-VFT) equation that accounts for both the temperature and salt concentration dependence. Furthermore, we find that, at any temperature, the concentration dependence of the conductivity is well described by the product of its infinite dilution value and a correction factor accounting for the reduced segmental mobility with increasing salt concentration. These results highlight the important role of polymer segmental mobility in the salt concentration dependence of ion conductivity for temperatures near and above the glass transition.
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Affiliation(s)
- Alexandros
J. Tsamopoulos
- Division of Chemistry and Chemical
Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Zhen-Gang Wang
- Division of Chemistry and Chemical
Engineering, California Institute of Technology, Pasadena, California 91125, United States
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5
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Hua H, Huang B, Yang X, Cheng J, Zhang P, Zhao J. Toward a molecular understanding of the conductivity of lithium-ion conducting polyanion polymer electrolytes by molecular dynamics simulation. Phys Chem Chem Phys 2023; 25:29894-29904. [PMID: 37901964 DOI: 10.1039/d3cp02225k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
With the improved lithium-ion transference number near unity, the low conductivity of single lithium-ion conducting solid polymer electrolytes (SLIC-SPEs) still hinders their application in high-rate batteries. Though some empirical conclusions on the conducting mechanism of SLIC-SPEs have been obtained, a more comprehensive study on the quantitative relationship between the molecular structure factors and ionic conduction performance is expected. In this study, a model structure that contains adjustable main chain and anion groups in the polyethylene oxide (PEO) matrix was used to clarify the influence of molecular structural factors on ionic conductivity and electrochemical stability of SLIC-SPEs. The anionic group was further disassembled into the intermediate group and end group while the main chain structure was distinguished into different degrees of polymerization and various lengths of the spacers between anions. Therefore, a well-defined molecular structure was employed to describe its relationship with ionic conductivity. In addition, the dissociation degree of salts and mobility of ions changing with the molecular structure were also discussed to explore the fundamental causes of conductivity. It can be concluded that the anion group affects the conductivity mainly via the dissociation degree, while the main chain structure impacts the conductivity by both dissociation degree and mobility.
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Affiliation(s)
- Haiming Hua
- College of Chemistry and Chemical Engineering, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, State Key Laboratory of Physical Chemistry of Solid Surfaces, Engineering Research Center of Electrochemical Technology, Ministry of Education, Collaborative Innovation Center of Chemistry for Energy Materials, Xiamen University, Xiamen 361005, Fujian, China.
| | - Boyang Huang
- College of Chemistry and Chemical Engineering, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, State Key Laboratory of Physical Chemistry of Solid Surfaces, Engineering Research Center of Electrochemical Technology, Ministry of Education, Collaborative Innovation Center of Chemistry for Energy Materials, Xiamen University, Xiamen 361005, Fujian, China.
| | - Xueying Yang
- College of Energy, Xiamen University, Xiamen 361102, Fujian, China.
| | - Jun Cheng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China.
| | - Peng Zhang
- College of Energy, Xiamen University, Xiamen 361102, Fujian, China.
| | - Jinbao Zhao
- College of Chemistry and Chemical Engineering, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, State Key Laboratory of Physical Chemistry of Solid Surfaces, Engineering Research Center of Electrochemical Technology, Ministry of Education, Collaborative Innovation Center of Chemistry for Energy Materials, Xiamen University, Xiamen 361005, Fujian, China.
- College of Energy, Xiamen University, Xiamen 361102, Fujian, China.
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6
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Chen X, Kong X. Nanoscale Confinement Effects on Ionic Conductivity of Solid Polymer Electrolytes: The Interplay between Diffusion and Dissociation. NANO LETTERS 2023. [PMID: 37220138 DOI: 10.1021/acs.nanolett.3c01171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Solid polymer electrolytes (SPEs) are attractive for next-generation lithium metal batteries but still suffer from low ionic conductivity. Nanostructured materials offer design concepts for SPEs with better performance. Using molecular dynamics simulation, we examine SPEs under nanoscale confinement, which has been demonstrated to accelerate the transport of neutral molecules such as water. Our results show that while ion diffusion indeed accelerates by more than 2 orders of magnitude as the channel diameter decreases from 15 to 2 nm, the ionic conductivity does not increase significantly in parallel. Instead, the ionic conductivity shows a nonmonotonic variation, with an optimal value above, but on the same order as, its bulk counterparts. This trend is due to enhanced ion association with decreasing channel size, which reduces the number of effective charge carriers. This effect competes with accelerated ion diffusion, leading to the nonmonotonicity in ion conductivity.
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Affiliation(s)
- Xiupeng Chen
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
| | - Xian Kong
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
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7
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Gullbrekken Ø, Røe IT, Selbach SM, Schnell SK. Charge Transport in Water-NaCl Electrolytes with Molecular Dynamics Simulations. J Phys Chem B 2023; 127:2729-2738. [PMID: 36921121 PMCID: PMC10068734 DOI: 10.1021/acs.jpcb.2c08047] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
Abstract
A systematic description of microscopic mechanisms is necessary to understand mass transport in solid and liquid electrolytes. From Molecular Dynamics (MD) simulations, transport properties can be computed and provide a detailed view of the molecular and ionic motions. In this work, ionic conductivity and transport numbers in electrolyte systems are computed from equilibrium and nonequilibrium MD simulations. Results from the two methods are compared with experimental results, and we discuss the significance of the frame of reference when determining and comparing transport numbers. Two ways of computing ionic conductivity from equilibrium simulations are presented: the Nernst-Einstein approximation or the Onsager coefficients. The Onsager coefficients take ionic correlations into account and are found to be more suitable for concentrated electrolytes. Main features and differences between equilibrium and nonequilibrium simulations are discussed, and some potential anomalies and critical pitfalls of using nonequilibrium molecular dynamics to determine transport properties are highlighted.
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Affiliation(s)
- Øystein Gullbrekken
- Department of Materials Science and Engineering, Norwegian University of Science and Technology, NTNU, Trondheim NO-7491, Norway
| | - Ingeborg Treu Røe
- Department of Materials Science and Engineering, Norwegian University of Science and Technology, NTNU, Trondheim NO-7491, Norway
| | - Sverre Magnus Selbach
- Department of Materials Science and Engineering, Norwegian University of Science and Technology, NTNU, Trondheim NO-7491, Norway
| | - Sondre Kvalvåg Schnell
- Department of Materials Science and Engineering, Norwegian University of Science and Technology, NTNU, Trondheim NO-7491, Norway
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8
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Mason TG, Freeman BD, Izgorodina EI. Influencing Molecular Dynamics Simulations of Ion-Exchange Membranes by Considering Comonomer Propagation. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c01743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Thomas G. Mason
- School of Chemistry, Monash University, Clayton, Melbourne, VIC3800, Australia
| | - Benny D. Freeman
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas78712, United States
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9
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Zhu C, Pedretti BJ, Kuehster L, Ganesan V, Sanoja GE, Lynd NA. Ionic Conductivity, Salt Partitioning, and Phase Separation in High-Dielectric Contrast Polyether Blends and Block Polymer Electrolytes. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c02023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Congzhi Zhu
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Benjamin J. Pedretti
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Louise Kuehster
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Venkat Ganesan
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Gabriel E. Sanoja
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Nathaniel A. Lynd
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
- Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712, United States
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10
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Ion Correlations and Partial Ionicities in the Lamellar Phases of Block Copolymeric Ionic Liquids. ACS Macro Lett 2022; 11:1265-1271. [DOI: 10.1021/acsmacrolett.2c00401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Fan M, Shen KH, Hall LM. Effect of Tethering Anions in Block Copolymer Electrolytes via Molecular Dynamics Simulations. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01309] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mengdi Fan
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Kuan-Hsuan Shen
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Lisa M. Hall
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
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12
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Zhu Z, Paddison SJ. Perspective: Morphology and ion transport in ion-containing polymers from multiscale modeling and simulations. Front Chem 2022; 10:981508. [PMID: 36059884 PMCID: PMC9437359 DOI: 10.3389/fchem.2022.981508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 07/14/2022] [Indexed: 11/20/2022] Open
Abstract
Ion-containing polymers are soft materials composed of polymeric chains and mobile ions. Over the past several decades they have been the focus of considerable research and development for their use as the electrolyte in energy conversion and storage devices. Recent and significant results obtained from multiscale simulations and modeling for proton exchange membranes (PEMs), anion exchange membranes (AEMs), and polymerized ionic liquids (polyILs) are reviewed. The interplay of morphology and ion transport is emphasized. We discuss the influences of polymer architecture, tethered ionic groups, rigidity of the backbone, solvents, and additives on both morphology and ion transport in terms of specific interactions. Novel design strategies are highlighted including precisely controlling molecular conformations to design highly ordered morphologies; tuning the solvation structure of hydronium or hydroxide ions in hydrated ion exchange membranes; turning negative ion-ion correlations to positive correlations to improve ionic conductivity in polyILs; and balancing the strength of noncovalent interactions. The design of single-ion conductors, well-defined supramolecular architectures with enhanced one-dimensional ion transport, and the understanding of the hierarchy of the specific interactions continue as challenges but promising goals for future research.
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Affiliation(s)
| | - Stephen J. Paddison
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN, United States
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13
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Pedretti BJ, Czarnecki NJ, Zhu C, Imbrogno J, Rivers F, Freeman BD, Ganesan V, Lynd NA. Structure–Property Relationships for Polyether-Based Electrolytes in the High-Dielectric-Constant Regime. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00639] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Benjamin J. Pedretti
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Natalie J. Czarnecki
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Congzhi Zhu
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Jennifer Imbrogno
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Frederick Rivers
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Benny D. Freeman
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Venkat Ganesan
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Nathaniel A. Lynd
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
- Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712, United States
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14
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Abstract
Ion-containing polymers have continued to be an important research focus for several decades due to their use as an electrolyte in energy storage and conversion devices. Elucidation of connections between the mesoscopic structure and multiscale dynamics of the ions and solvent remains incompletely understood. Coarse-grained modeling provides an efficient approach for exploring the structural and dynamical properties of these soft materials. The unique physicochemical properties of such polymers are of broad interest. In this review, we summarize the current development and understanding of the structure-property relationship of ion-containing polymers and provide insights into the design of such materials determined from coarse-grained modeling and simulations accompanying significant advances in experimental strategies. We specifically concentrate on three types of ion-containing polymers: proton exchange membranes (PEMs), anion exchange membranes (AEMs), and polymerized ionic liquids (polyILs). We posit that insight into the similarities and differences in these materials will lead to guidance in the rational design of high-performance novel materials with improved properties for various power source technologies.
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Affiliation(s)
- Zhenghao Zhu
- Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Xubo Luo
- Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Stephen J Paddison
- Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
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15
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Ying C, Houghtaling J, Mayer M. Effects of off-axis translocation through nanopores on the determination of shape and volume estimates for individual particles. NANOTECHNOLOGY 2022; 33:275501. [PMID: 35320779 DOI: 10.1088/1361-6528/ac6087] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
Resistive pulses generated by nanoparticles that translocate through a nanopore contain multi-parametric information about the physical properties of those particles. For example, non-spherical particles sample several different orientations during translocation, producing fluctuations in blockade current that relate to their shape. Due to the heterogenous distribution of electric field from the center to the wall of a nanopore while a particle travels through the pore, its radial position influences the blockade current, thereby affecting the quantification of parameters related to the particle's characteristics. Here, we investigate the influence of these off-axis effects on parameters estimated by performing finite element simulations of dielectric particles transiting a cylindrical nanopore. We varied the size, ellipsoidal shape, and radial position of individual particles, as well as the size of the nanopore. As expected, nanoparticles translocating near the nanopore wall produce increase current blockades, resulting in overestimates of particle volume. We demonstrated that off-axis effects also influence estimates of shape determined from resistive pulse analyses, sometimes producing a multiple-fold deviation in ellipsoidal length-to-diameter ratio between estimates and reference values. By using a nanopore with the minimum possible diameter that still allows the particle to rotate while translocating, off-axis effects on the determination of both volume and shape can be minimized. In addition, tethering the nanoparticles to a fluid coating on the nanopore wall makes it possible to determine an accurate particle shape with an overestimated volume. This work provides a framework to select optimal ratios of nanopore to nanoparticle size for experiments targeting free translocations.
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Affiliation(s)
- Cuifeng Ying
- Adolphe Merkle Institute, University of Fribourg, Fribourg, Switzerland
- Advanced Optics and Photonics Laboratory, Department of Engineering, School of Science &Technology, Nottingham Trent University, Nottingham, United Kingdom
| | - Jared Houghtaling
- Adolphe Merkle Institute, University of Fribourg, Fribourg, Switzerland
| | - Michael Mayer
- Adolphe Merkle Institute, University of Fribourg, Fribourg, Switzerland
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16
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Zhang Z, Zofchak E, Krajniak J, Ganesan V. Influence of Polarizability on the Structure, Dynamic Characteristics, and Ion-Transport Mechanisms in Polymeric Ionic Liquids. J Phys Chem B 2022; 126:2583-2592. [DOI: 10.1021/acs.jpcb.1c10662] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zidan Zhang
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Everett Zofchak
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Jakub Krajniak
- Independent Researcher, os. Kosmonautow 13/56, 61-631 Poznan, Poland
| | - Venkat Ganesan
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
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17
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Lytle TK, Yethiraj A. The effect of explicit counterion binding on the transference number of polyelectrolyte solutions. J Chem Phys 2022; 156:104901. [DOI: 10.1063/5.0083414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Polyelectrolyte solutions have been proposed as a method to improve the efficiency of lithium-ion batteries by increasing the cation transference number because the polymer self-diffusion coefficient is much lower than that of the counterion. However, this is not necessarily true for the polymer mobility. In some cases, negative transference numbers have been reported, which implies that the lithium ions are transporting to the same electrode as the anion, behavior that is often attributed to a binding of counterions to the polyion. We use a simple model where we bind some counterions to the polymer via harmonic springs to investigate this phenomenon. We find that both the number of bound counterions and the strength of their binding alter the transference number, and, in some cases, the transference number is negative. We also investigate how the transference number depends on the Manning parameter, the ratio of the Bjerrum length to charge separation along the chain. By altering the Manning parameter, the transference number can almost be doubled, which suggests that charge spacing could be a way to increase the transference number of polyelectrolyte solutions.
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Affiliation(s)
- T. K. Lytle
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - A. Yethiraj
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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18
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Ghosh D, Sakpal SS, Chatterjee S, Deshmukh SH, Kwon H, Kim YS, Bagchi S. Association-Dissociation Dynamics of Ionic Electrolytes in Low Dielectric Medium. J Phys Chem B 2021; 126:239-248. [PMID: 34961310 DOI: 10.1021/acs.jpcb.1c08613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ionic electrolytes are known to form various complexes which exist in dynamic equilibrium in a low dielectric medium. However, structural characterization of these complexes has always posed a great challenge to the scientific community. An additional challenge is the estimation of the dynamic association-dissociation time scales (lifetime of the complexes), which are key to the fundamental understanding of ion transport. In this work, we have used a combination of infrared absorption spectroscopy, two-dimensional infrared spectroscopy, molecular dynamics simulations, and density functional theory calculations to characterize the various ion complexes formed by the thiocyanate-based ionic electrolytes as a function of different cations in a low dielectric medium. Our results demonstrate that thiocyanate is an excellent vibrational reporter of the heterogeneous ion complexes undergoing association-dissociation dynamics. We find that the ionic electrolytes exist as contact ion pairs, dimers, and clusters in a low dielectric medium. The relative ratios of the various ion complexes are sensitive to the cations. In addition to the interactions between the thiocyanate anion and the countercation, the solute-solvent interactions drive the dynamic equilibrium. We have estimated the association-dissociation dynamics time scales from two-dimensional infrared spectroscopy. The exchange time scale involving the cluster is faster than that between a dimer and an ion pair. Moreover, we find that the dynamic equilibrium between the cluster and another ion complex is correlated to the solvent fluctuations.
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Affiliation(s)
- Deborin Ghosh
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
| | - Sushil S Sakpal
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Srijan Chatterjee
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Samadhan H Deshmukh
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Hyejin Kwon
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Korea
| | - Yung Sam Kim
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Korea
| | - Sayan Bagchi
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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19
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Rosenwinkel MP, Schönhoff M. Polymer‐Induced Inversion of the Li
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Drift Direction in Ionic Liquid‐Based Ternary Polymer Electrolytes. MACROMOL CHEM PHYS 2021. [DOI: 10.1002/macp.202100320] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Mark P. Rosenwinkel
- Institute of Physical Chemistry University of Münster Corrensstraße 28/30 Münster 48149 Germany
| | - Monika Schönhoff
- Institute of Physical Chemistry University of Münster Corrensstraße 28/30 Münster 48149 Germany
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20
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Affiliation(s)
- Jelena Popovic
- Max Planck Institute for Solid State Research Heisenbergstr. 1 Stuttgart 70569 Germany
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21
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Genier FS, Hosein ID. Effect of Coordination Behavior in Polymer Electrolytes for Sodium-Ion Conduction: A Molecular Dynamics Study of Poly(ethylene oxide) and Poly(tetrahydrofuran). Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Francielli S. Genier
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Ian D. Hosein
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
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22
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Gudla H, Shao Y, Phunnarungsi S, Brandell D, Zhang C. Importance of the Ion-Pair Lifetime in Polymer Electrolytes. J Phys Chem Lett 2021; 12:8460-8464. [PMID: 34449227 PMCID: PMC8436209 DOI: 10.1021/acs.jpclett.1c02474] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 08/25/2021] [Indexed: 06/13/2023]
Abstract
Ion pairing is commonly considered as a culprit for the reduced ionic conductivity in polymer electrolyte systems. However, this simple thermodynamic picture should not be taken literally, as ion pairing is a dynamical phenomenon. Here we construct model poly(ethylene oxide)-bis(trifluoromethane)sulfonimide lithium salt systems with different degrees of ion pairing by tuning the solvent polarity and examine the relation between the cation-anion distinct conductivity σ+-d and the lifetime of ion pairs τ+- using molecular dynamics simulations. It is found that there exist two distinct regimes where σ+-d scales with 1/τ+- and τ+-, respectively, and the latter is a signature of longer-lived ion pairs that contribute negatively to the total ionic conductivity. This suggests that ion pairs are kinetically different depending on the solvent polarity, which renders the ion-pair lifetime highly important when discussing its effect on ion transport in polymer electrolyte systems.
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Affiliation(s)
- Harish Gudla
- Department of Chemistry-Ångström
Laboratory, Uppsala University, Lägerhyddsvägen 1, Box 538, 75121 Uppsala, Sweden
| | - Yunqi Shao
- Department of Chemistry-Ångström
Laboratory, Uppsala University, Lägerhyddsvägen 1, Box 538, 75121 Uppsala, Sweden
| | - Supho Phunnarungsi
- Department of Chemistry-Ångström
Laboratory, Uppsala University, Lägerhyddsvägen 1, Box 538, 75121 Uppsala, Sweden
| | - Daniel Brandell
- Department of Chemistry-Ångström
Laboratory, Uppsala University, Lägerhyddsvägen 1, Box 538, 75121 Uppsala, Sweden
| | - Chao Zhang
- Department of Chemistry-Ångström
Laboratory, Uppsala University, Lägerhyddsvägen 1, Box 538, 75121 Uppsala, Sweden
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23
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Imbrogno J, Maruyama K, Rivers F, Baltzegar JR, Zhang Z, Meyer PW, Ganesan V, Aoshima S, Lynd NA. Relationship between Ionic Conductivity, Glass Transition Temperature, and Dielectric Constant in Poly(vinyl ether) Lithium Electrolytes. ACS Macro Lett 2021; 10:1002-1007. [PMID: 35549112 DOI: 10.1021/acsmacrolett.1c00305] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report a partial elucidation of the relationship between polymer polarity and ionic conductivity in polymer electrolyte mixtures comprising a homologous series of nine poly(vinyl ether)s (PVEs) and lithium bis(trifluoromethylsulfonyl)imide. Recent simulation studies have suggested that low dielectric polymer hosts with glass transition temperatures far below ambient conditions are expected to have ionic conductivity limited by salt solubility and dissociation. In contrast, high dielectric hosts are expected to have the potential for high ion solubility but slow segmental dynamics due to strong polymer-polymer and polymer-ion interactions. We report results for PVEs in the low polarity regime with dielectric constants of about 1.3 to 9.0. Ionic conductivity measured for the PVE and salt mixtures ranged from about 10-10 to 10-3 S/cm. In agreement with the predictions from computer simulations, the ionic conductivity increased with dielectric constant and plateaued as the dielectric approached 9.0, comparable to the dielectric constant of the widely used poly(ethylene oxide).
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Affiliation(s)
| | - Kazuya Maruyama
- Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | | | | | | | | | | | - Sadahito Aoshima
- Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
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24
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Tekell MC, Kumar SK. Structure and Dynamics of Stockmayer Polymer Electrolyte. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marshall C. Tekell
- Department of Chemical Engineering, Columbia University, New York, New York 10027, United States
| | - Sanat K. Kumar
- Department of Chemical Engineering, Columbia University, New York, New York 10027, United States
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25
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Ketkar PM, Shen KH, Fan M, Hall LM, Epps TH. Quantifying the Effects of Monomer Segment Distributions on Ion Transport in Tapered Block Polymer Electrolytes. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00941] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Priyanka M. Ketkar
- Department of Chemical & Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Kuan-Hsuan Shen
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Mengdi Fan
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Lisa M. Hall
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Thomas H. Epps
- Department of Chemical & Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
- Department of Materials Science & Engineering, University of Delaware, Newark, Delaware 19716, United States
- Center for Research in Soft matter & Polymers (CRiSP), University of Delaware, Newark, Delaware 19716, United States
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26
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Zhang Z, Krajniak J, Ganesan V. A Multiscale Simulation Study of Influence of Morphology on Ion Transport in Block Copolymeric Ionic Liquids. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00025] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Zidan Zhang
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Jakub Krajniak
- Independent researcher, os. Kosmonautow 13/56, 61-631 Poznan, Poland
| | - Venkat Ganesan
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
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27
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Fong KD, Self J, McCloskey BD, Persson KA. Ion Correlations and Their Impact on Transport in Polymer-Based Electrolytes. Macromolecules 2021. [DOI: 10.1021/acs.macromol.0c02545] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Kara D. Fong
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California 94720, United States
- Energy Technologies Area, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Julian Self
- Energy Technologies Area, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, California 94720, United States
| | - Bryan D. McCloskey
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California 94720, United States
- Energy Technologies Area, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Kristin A. Persson
- Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, California 94720, United States
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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28
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Sharon D, Bennington P, Webb MA, Deng C, de Pablo JJ, Patel SN, Nealey PF. Molecular Level Differences in Ionic Solvation and Transport Behavior in Ethylene Oxide-Based Homopolymer and Block Copolymer Electrolytes. J Am Chem Soc 2021; 143:3180-3190. [DOI: 10.1021/jacs.0c12538] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Daniel Sharon
- Pritzker School of Molecular Engineering, University of Chicago, 5640 S Ellis Ave, Chicago, Illinois 60637, United States
- Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
| | - Peter Bennington
- Pritzker School of Molecular Engineering, University of Chicago, 5640 S Ellis Ave, Chicago, Illinois 60637, United States
| | - Michael A. Webb
- Department of Chemical and Biological Engineering, Princeton University, 41 Olden St, Princeton, New Jersey 08540, United States
| | - Chuting Deng
- Pritzker School of Molecular Engineering, University of Chicago, 5640 S Ellis Ave, Chicago, Illinois 60637, United States
| | - Juan J. de Pablo
- Pritzker School of Molecular Engineering, University of Chicago, 5640 S Ellis Ave, Chicago, Illinois 60637, United States
- Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
| | - Shrayesh N. Patel
- Pritzker School of Molecular Engineering, University of Chicago, 5640 S Ellis Ave, Chicago, Illinois 60637, United States
| | - Paul F. Nealey
- Pritzker School of Molecular Engineering, University of Chicago, 5640 S Ellis Ave, Chicago, Illinois 60637, United States
- Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
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29
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Shen KH, Fan M, Hall LM. Molecular Dynamics Simulations of Ion-Containing Polymers Using Generic Coarse-Grained Models. Macromolecules 2021. [DOI: 10.1021/acs.macromol.0c02557] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Kuan-Hsuan Shen
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Mengdi Fan
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Lisa M. Hall
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
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30
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Galluzzo MD, Loo WS, Schaible E, Zhu C, Balsara NP. Dynamic Structure and Phase Behavior of a Block Copolymer Electrolyte under dc Polarization. ACS APPLIED MATERIALS & INTERFACES 2020; 12:57421-57430. [PMID: 33307687 DOI: 10.1021/acsami.0c16209] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
An important consideration when designing lithium battery electrolytes for advanced applications is how the electrolyte facilitates ion transport at fast charge and discharge rates. Large current densities are accompanied by large salt concentration gradients across the electrolyte. Nanostructured composite electrolytes have been proposed to enable the use of high energy density lithium metal anodes, but many questions about the interplay between the electrolyte morphology and the salt concentration gradient that forms under dc polarization remain unanswered. To address these questions, we use an in situ small-angle X-ray scattering technique to examine the nanostructure of a polystyrene-block-poly(ethylene oxide) copolymer electrolyte under dc polarization with spatial and temporal resolution. In the quiescent state, the electrolyte exhibits a lamellar morphology. The passage of ionic current in a lithium symmetric cell leads to the formation of concurrent phases: a disordered morphology near the negative electrode, lamellae in the center of the cell, and coexisting lamellae and gyroid near the positive electrode. The most surprising result of this study was obtained after the applied electric field was turned off: a current-induced gyroid phase grows in volume for 6 h in spite of the absence of an obvious driving force. We show that this reflects the formation of localized pockets of salt-dense electrolyte, termed concentration hotspots, under dc polarization. Our methods may be applied to understand the dynamic structure of composite electrolytes at appreciable current densities.
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Affiliation(s)
- Michael D Galluzzo
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Whitney S Loo
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Eric Schaible
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Chenhui Zhu
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Nitash P Balsara
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Joint Center for Energy Storage Research (JCESR), Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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31
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Shen KH, Hall LM. Effects of Ion Size and Dielectric Constant on Ion Transport and Transference Number in Polymer Electrolytes. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c02161] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Kuan-Hsuan Shen
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Lisa M. Hall
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
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32
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Gudla H, Zhang C, Brandell D. Effects of Solvent Polarity on Li-ion Diffusion in Polymer Electrolytes: An All-Atom Molecular Dynamics Study with Charge Scaling. J Phys Chem B 2020; 124:8124-8131. [PMID: 32840375 PMCID: PMC7503542 DOI: 10.1021/acs.jpcb.0c05108] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 08/24/2020] [Indexed: 11/29/2022]
Abstract
We herein report an all-atom molecular dynamics study on the role of solvent polarity for Li+ diffusion in polymer electrolytes using PEO-LiTFSI (poly(ethylene oxide)-lithium bis(trifluoromethane)sulfonimide) as a model system. By separating the effect of Tg and the effect of solvent polarity in our simulations, we show that the maximum in the diffusion coefficient of Li+ with respect to the dielectric constant of polymer solvent εp is due to transitions in the transport mechanism. In particular, it is found that the frequent interchain hopping involves the coordination of both PEO and TFSI. This optimal solvating ability of PEO at an intermediate value of εp leads to the fast ion conduction. These findings highlight the synergetic effect of solvent polarity and bond polarity on Li-ion diffusion in solid polymer electrolytes.
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Affiliation(s)
- Harish Gudla
- Department of Chemistry—Ångström
Laboratory, Uppsala University, Lägerhyddsvägen 1, Box 538, 75121 Uppsala, Sweden
| | - Chao Zhang
- Department of Chemistry—Ångström
Laboratory, Uppsala University, Lägerhyddsvägen 1, Box 538, 75121 Uppsala, Sweden
| | - Daniel Brandell
- Department of Chemistry—Ångström
Laboratory, Uppsala University, Lägerhyddsvägen 1, Box 538, 75121 Uppsala, Sweden
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