101
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Rong Q, Liu XB, Chen C, Hu YL. Novel and Sustainable Solvent‐Free Synthesis of 2‐Oxazolidinones Using Periodic Mesoporous Organosilica‐Supported Triazolium Ionic Liquids as Highly Active Catalysts. ChemistrySelect 2021. [DOI: 10.1002/slct.202103442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Qi Rong
- College of Materials and Chemical Engineering Key laboratory of inorganic nonmetallic crystalline and energy conversion materials China Three Gorges University Yichang 443002 Hubei province P. R. China
| | - Xiao Bing Liu
- College of Chemistry and Chemical Engineering Jinggangshan University Ji'an 343009 P. R. China
| | - Chen Chen
- College of Environmental and Chemical Engineering Jiangsu University of Science and Technology Zhenjiang 212003 P. R. China
| | - Yu Lin Hu
- College of Materials and Chemical Engineering Key laboratory of inorganic nonmetallic crystalline and energy conversion materials China Three Gorges University Yichang 443002 Hubei province P. R. China
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102
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Cai Y, Zhang Q, Lu Y, Hao Z, Ni Y, Chen J. An Ionic Liquid Electrolyte with Enhanced Li
+
Transport Ability Enables Stable Li Deposition for High‐Performance Li‐O
2
Batteries. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111360] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Yichao Cai
- Frontiers Science Center for New Organic Matter Renewable Energy Conversion and Storage Center (RECAST) Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) College of Chemistry Nankai University Tianjin 300071 China
| | - Qiu Zhang
- Frontiers Science Center for New Organic Matter Renewable Energy Conversion and Storage Center (RECAST) Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) College of Chemistry Nankai University Tianjin 300071 China
| | - Yong Lu
- Frontiers Science Center for New Organic Matter Renewable Energy Conversion and Storage Center (RECAST) Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) College of Chemistry Nankai University Tianjin 300071 China
| | - Zhimeng Hao
- Frontiers Science Center for New Organic Matter Renewable Energy Conversion and Storage Center (RECAST) Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) College of Chemistry Nankai University Tianjin 300071 China
| | - Youxuan Ni
- Frontiers Science Center for New Organic Matter Renewable Energy Conversion and Storage Center (RECAST) Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) College of Chemistry Nankai University Tianjin 300071 China
| | - Jun Chen
- Frontiers Science Center for New Organic Matter Renewable Energy Conversion and Storage Center (RECAST) Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) College of Chemistry Nankai University Tianjin 300071 China
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103
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Rauber D, Philippi F, Kuttich B, Becker J, Kraus T, Hunt P, Welton T, Hempelmann R, Kay CWM. Curled cation structures accelerate the dynamics of ionic liquids. Phys Chem Chem Phys 2021; 23:21042-21064. [PMID: 34522943 DOI: 10.1039/d1cp02889h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ionic liquids are modern liquid materials with potential and actual implementation in many advanced technologies. They combine many favourable and modifiable properties but have a major inherent drawback compared to molecular liquids - slower dynamics. In previous studies we found that the dynamics of ionic liquids are significantly accelerated by the introduction of multiple ether side chains into the cations. However, the origin of the improved transport properties, whether as a result of the altered cation conformation or due to the absence of nanostructuring within the liquid as a result of the higher polarity of the ether chains, remained to be clarified. Therefore, we prepared two novel sets of methylammonium based ionic liquids; one set with three ether substituents and another set with three butyl side chains, in order to compare their dynamic properties and liquid structures. Using a range of anions, we show that the dynamics of the ether-substituted cations are systematically and distinctly accelerated. Liquefaction temperatures are lowered and fragilities increased, while at the same time cation-anion distances are slightly larger for the alkylated samples. Furthermore, pronounced liquid nanostructures were not observed. Molecular dynamics simulations demonstrate that the origin of the altered properties of the ether substituted ionic liquids is primarily due to a curled ether chain conformation, in contrast to the alkylated cations where the alkyl chains retain a linear conformation. Thus, the observed structure-property relations can be explained by changes in the geometric shape of the cations, rather than by the absence of a liquid nanostructure. Application of quantum chemical calculations to a simplified model system revealed that intramolecular hydrogen-bonding is responsible for approximately half of the stabilisation of the curled ether-cations, whereas the other half stems from non-specific long-range interactions. These findings give more detailed insights into the structure-property relations of ionic liquids and will guide the development of ionic liquids that do not suffer from slow dynamics.
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Affiliation(s)
- Daniel Rauber
- Department of Chemistry, Saarland University, Campus B2.2, 66123, Saarbrücken, Germany.
| | - Frederik Philippi
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, UK
| | - Björn Kuttich
- INM-Leibniz Institute for New Materials, Campus D2.2, 66123, Saarbrücken, Germany
| | - Julian Becker
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, UK
| | - Tobias Kraus
- Department of Chemistry, Saarland University, Campus B2.2, 66123, Saarbrücken, Germany. .,INM-Leibniz Institute for New Materials, Campus D2.2, 66123, Saarbrücken, Germany
| | - Patricia Hunt
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, UK.,School of Chemical and Physical Sciences, Victoria University of Wellington, New Zealand
| | - Tom Welton
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, UK
| | - Rolf Hempelmann
- Department of Chemistry, Saarland University, Campus B2.2, 66123, Saarbrücken, Germany.
| | - Christopher W M Kay
- Department of Chemistry, Saarland University, Campus B2.2, 66123, Saarbrücken, Germany. .,London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH, UK.
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104
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Ivanov MY, Prikhod’ko SA, Bakulina OD, Kiryutin AS, Adonin NY, Fedin MV. Validation of Structural Grounds for Anomalous Molecular Mobility in Ionic Liquid Glasses. Molecules 2021; 26:5828. [PMID: 34641371 PMCID: PMC8510339 DOI: 10.3390/molecules26195828] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/21/2021] [Accepted: 09/23/2021] [Indexed: 11/25/2022] Open
Abstract
Ionic liquid (IL) glasses have recently drawn much interest as unusual media with unique physicochemical properties. In particular, anomalous suppression of molecular mobility in imidazolium IL glasses vs. increasing temperature was evidenced by pulse Electron Paramagnetic Resonance (EPR) spectroscopy. Although such behavior has been proven to originate from dynamics of alkyl chains of IL cations, the role of electron spin relaxation induced by surrounding protons still remains unclear. In this work we synthesized two deuterated imidazolium-based ILs to reduce electron-nuclear couplings between radical probe and alkyl chains of IL, and investigated molecular mobility in these glasses. The obtained trends were found closely similar for deuterated and protonated analogs, thus excluding the relaxation-induced artifacts and reliably demonstrating structural grounds of the observed anomalies in heterogeneous IL glasses.
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Affiliation(s)
- Mikhail Yu. Ivanov
- International Tomography Center SB RAS, Institutskaya Street 3a, 630090 Novosibirsk, Russia; (O.D.B.); (A.S.K.)
| | - Sergey A. Prikhod’ko
- Boreskov Institute of Catalysis SB RAS, Lavrentiev Avenue 5, 630090 Novosibirsk, Russia; (S.A.P.); (N.Y.A.)
| | - Olga D. Bakulina
- International Tomography Center SB RAS, Institutskaya Street 3a, 630090 Novosibirsk, Russia; (O.D.B.); (A.S.K.)
| | - Alexey S. Kiryutin
- International Tomography Center SB RAS, Institutskaya Street 3a, 630090 Novosibirsk, Russia; (O.D.B.); (A.S.K.)
| | - Nicolay Yu. Adonin
- Boreskov Institute of Catalysis SB RAS, Lavrentiev Avenue 5, 630090 Novosibirsk, Russia; (S.A.P.); (N.Y.A.)
| | - Matvey V. Fedin
- International Tomography Center SB RAS, Institutskaya Street 3a, 630090 Novosibirsk, Russia; (O.D.B.); (A.S.K.)
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105
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Chen XM, Jiang X, Jing Y, Chen X. Synthesis and Dehydrogenation of Organic Salts of a Five-Membered B/N Anionic Chain, a Novel Ionic Liquid. Chem Asian J 2021; 16:2475-2480. [PMID: 34245108 DOI: 10.1002/asia.202100632] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 07/07/2021] [Indexed: 01/02/2023]
Abstract
We have synthesized the tetrabutylammonium ([Bu4 N]+ ), tetraethylammonium ([Et4 N]+ ), guanidinium ([C(NH2 )3 ]+ ), and methylguanidinium ([C(N3 H5 CH3 )]+ ) salts of the [BH3 (NH2 BH2 )2 H]- anion, a five-membered B/N anionic chain, in high yields by the metathesis reactions of Na[BH3 (NH2 BH2 )2 H] with the corresponding halides and characterized them by NMR (11 B, 11 B{1 H}, 1 H, 1 H{11 B}, 13 C), IR, elemental analysis, TGA-DSC, and TGA-MS. These complexes behave like ionic liquids (ILs), in which the melting point of the [Bu4 N][BH3 (NH2 BH2 )2 H] is the lowest (-51 °C). The dehydrogenation of these ILs have been studied through the thermal decomposition and catalytic hydrolysis in aqueous solution using the noble or non-noble metals or their salts as catalysts, and the results indicate that these ILs of five-membered B/N anionic chain are promising hydrogen storage materials.
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Affiliation(s)
- Xi-Meng Chen
- School of Chemistry and Chemical Engineering, Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Henan Normal University, Xinxiang, Henan, 453007, P. R. China
| | - Xin Jiang
- School of Chemistry and Chemical Engineering, Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Henan Normal University, Xinxiang, Henan, 453007, P. R. China
| | - Yi Jing
- School of Chemistry and Chemical Engineering, Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Henan Normal University, Xinxiang, Henan, 453007, P. R. China
| | - Xuenian Chen
- School of Chemistry and Chemical Engineering, Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Henan Normal University, Xinxiang, Henan, 453007, P. R. China.,Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan, 450001, P. R. China
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106
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Yang L, Kong D, Chang X, Jiang G, Ao T, Xie C, Kinkeyi Moukoko AD, Ma J. Counterion-specific shale hydration inhibiting performance of vinylimdazolium ionic liquids. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116544] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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107
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Structure-Property Relation of Trimethyl Ammonium Ionic Liquids for Battery Applications. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11125679] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Ionic liquids are attractive and safe electrolytes for diverse electrochemical applications such as advanced rechargeable batteries with high energy densities. Their properties that are beneficial for energy storage and conversion include negligible vapor-pressure, intrinsic conductivity as well as high stability. To explore the suitability of a series of ionic liquids with small ammonium cations for potential battery applications, we investigated their thermal and transport properties. We studied the influence of the symmetrical imide-type anions bis(trifluoromethanesulfonyl)imide ([TFSI]−) and bis(fluorosulfonyl)imide ([FSI]−), side chain length and functionalization, as well as lithium salt content on the properties of the electrolytes. Many of the samples are liquid at ambient temperature, but their solidification temperatures show disparate behavior. The transport properties showed clear trends: the dynamics are accelerated for samples with the [FSI]− anion, shorter side chains, ether functionalization and lower amounts of lithium salts. Detailed insight was obtained from the diffusion coefficients of the different ions in the electrolytes, which revealed the formation of aggregates of lithium cations coordinated by anions. The ionic liquid electrolytes exhibit sufficient stability in NMC/Li half-cells at elevated temperatures with small current rates without the need of additional liquid electrolytes, although Li-plating was observed. Electrolytes containing [TFSI]− anions showed superior stability compared to those with [FSI]− anions in battery tests.
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108
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Avula NVS, Karmakar A, Kumar R, Balasubramanian S. Efficient Parametrization of Force Field for the Quantitative Prediction of the Physical Properties of Ionic Liquid Electrolytes. J Chem Theory Comput 2021; 17:4274-4290. [PMID: 34097391 DOI: 10.1021/acs.jctc.1c00268] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The prediction of transport properties of room-temperature ionic liquids from nonpolarizable force field-based simulations has long been a challenge. The uniform charge scaling method has been widely used to improve the agreement with the experiment by incorporating the polarizability and charge transfer effects in an effective manner. While this method improves the performance of the force fields, this prescription is ad hoc in character; further, a quantitative prediction is still not guaranteed. In such cases, the nonbonded interaction parameters too need to be refined, which requires significant effort. In this work, we propose a three-step semiautomated refinement procedure based on (1) atomic site charges obtained from quantum calculations of the bulk condensed phase; (2) quenched Monte Carlo optimizer to shortlist suitable force field candidates, which are then tested using pilot simulations; and (3) manual refinement to further improve the accuracy of the force field. The strategy is designed in a sequential manner with each step improving the accuracy over the previous step, allowing the users to invest the effort commensurate with the desired accuracy of the refined force field. The refinement procedure is applied on N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide (DEME-TFSI), a front-runner as an electrolyte for electric double-layer capacitors and single-molecule-based devices. The transferability of the refined force field is tested on N,N-dimethyl-N-ethyl-N-methoxyethoxyethylammonium bis(trifluoromethanesulfonyl)imide (N112,2O2O1-TFSI). The refined force field is found to be better at predicting both structural and transport properties compared to the uniform charge scaling procedure, which showed a discrepancy in the X-ray structure factor. The refined force field showed quantitative agreement with structural (density and X-ray structure factor) and transport properties-diffusion coefficients, ionic conductivity, and shear viscosity over a wide temperature range, building a case for the wide adoption of the procedure.
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Affiliation(s)
- Nikhil V S Avula
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Anwesa Karmakar
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Rahul Kumar
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Sundaram Balasubramanian
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
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109
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Marion S, Vučemilović-Alagić N, Špadina M, Radenović A, Smith AS. From Water Solutions to Ionic Liquids with Solid State Nanopores as a Perspective to Study Transport and Translocation Phenomena. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2100777. [PMID: 33955694 DOI: 10.1002/smll.202100777] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/01/2021] [Indexed: 06/12/2023]
Abstract
Solid state nanopores are single-molecular devices governed by nanoscale physics with a broad potential for technological applications. However, the control of translocation speed in these systems is still limited. Ionic liquids are molten salts which are commonly used as alternate solvents enabling the regulation of the chemical and physical interactions on solid-liquid interfaces. While their combination can be challenging to the understanding of nanoscopic processes, there has been limited attempts on bringing these two together. While summarizing the state of the art and open questions in these fields, several major advances are presented with a perspective on the next steps in the investigations of ionic-liquid filled nanopores, both from a theoretical and experimental standpoint. By analogy to aqueous solutions, it is argued that ionic liquids and nanopores can be combined to provide new nanofluidic functionalities, as well as to help resolve some of the pertinent problems in understanding transport phenomena in confined ionic liquids and providing better control of the speed of translocating analytes.
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Affiliation(s)
- Sanjin Marion
- Laboratory of Nanoscale Biology, Institute of Bioengineering, School of Engineering, EPFL, 1015, Lausanne, Switzerland
| | - Nataša Vučemilović-Alagić
- Group for Computational Life Sciences, Ruđer Bošković Institute, Division of Physical Chemistry, 10000, Zagreb, Croatia
- PULS Group, Physics Department, Interdisciplinary Center for Nanostructured Films, FAU Erlangen-Nürnberg, 91058, Erlangen, Germany
| | - Mario Špadina
- Group for Computational Life Sciences, Ruđer Bošković Institute, Division of Physical Chemistry, 10000, Zagreb, Croatia
| | - Aleksandra Radenović
- Laboratory of Nanoscale Biology, Institute of Bioengineering, School of Engineering, EPFL, 1015, Lausanne, Switzerland
| | - Ana-Sunčana Smith
- Group for Computational Life Sciences, Ruđer Bošković Institute, Division of Physical Chemistry, 10000, Zagreb, Croatia
- PULS Group, Physics Department, Interdisciplinary Center for Nanostructured Films, FAU Erlangen-Nürnberg, 91058, Erlangen, Germany
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110
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Dong Y, Laaksonen A, Huo F, Gao Q, Ji X. Hydrated Ionic Liquids Boost the Trace Detection Capacity of Proteins on TiO 2 Support. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:5012-5021. [PMID: 33861604 PMCID: PMC8154861 DOI: 10.1021/acs.langmuir.1c00525] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 04/06/2021] [Indexed: 05/05/2023]
Abstract
Trace detection based on surface-enhanced Raman scattering (SERS) has attracted considerable attention, and exploiting efficient strategies to stretch the limit of detection and understanding the mechanisms on molecular level are of utmost importance. In this work, we use ionic liquids (ILs) as trace additives in a protein-TiO2 system, allowing us to obtain an exceptionally low limit of detection down to 10-9 M. The enhancement factors (EFs) were determined to 2.30 × 104, 6.17 × 104, and 1.19 × 105, for the three systems: one without ILs, one with ILs in solutions, and one with ILs immobilized on the TiO2 substrate, respectively, corresponding to the molecular forces of 1.65, 1.32, and 1.16 nN quantified by the atomic force microscopy. The dissociation and following hydration of ILs, occurring in the SERS system, weakened the molecular forces but instead improved the electron transfer ability of ILs, which is the major contribution for the observed excellent detection. The weaker diffusion of the hydrated IL ions immobilized on the TiO2 substrate did provide a considerably greater EF value, compared to the ILs in the solution. This work clearly demonstrates the importance of the hydration of ions, causing an improved electron transfer ability of ILs and leading to an exceptional SERS performance in the field of trace detection. Our results should stimulate further development to use ILs in SERS and related applications in bioanalysis, medical diagnosis, and environmental science.
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Affiliation(s)
- Yihui Dong
- Beijing
Key Laboratory of Ionic Liquids Clean Process, CAS Key Laboratory
of Green Process and Engineering, State Key Laboratory of Multiphase
Complex Systems, Institute of Process Engineering,
Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Aatto Laaksonen
- Energy
Engineering, Division of Energy Science, Luleå University of Technology, 97187 Luleå, Sweden
- Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm SE-10691, Sweden
- State
Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Centre
of Advanced Research in Bionanoconjugates and Biopolymers, Petru Poni Institute of Macromolecular Chemistry, Iasi 700487, Romania
| | - Feng Huo
- Beijing
Key Laboratory of Ionic Liquids Clean Process, CAS Key Laboratory
of Green Process and Engineering, State Key Laboratory of Multiphase
Complex Systems, Institute of Process Engineering,
Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Qingwei Gao
- State Key
Laboratory of Chemical Engineering and School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, P. R. China
| | - Xiaoyan Ji
- Energy
Engineering, Division of Energy Science, Luleå University of Technology, 97187 Luleå, Sweden
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111
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Golub B, Fumino K, Stange P, Fossog V, Hempelmann R, Ondo D, Paschek D, Ludwig R. Balance Between Contact and Solvent-Separated Ion Pairs in Mixtures of the Protic Ionic Liquid [Et 3NH][MeSO 3] with Water Controlled by Water Content and Temperature. J Phys Chem B 2021; 125:4476-4488. [PMID: 33899479 DOI: 10.1021/acs.jpcb.1c01850] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The formation of aggregates of ionic species is a crucial process in liquids and solutions. Ion speciation is particularly interesting for the case of ionic liquids (ILs) since these Coulombic fluids consist solely of ions. Most of their unique properties, such as enthalpies of vaporization and conductivities, are strongly related to ion pair formation. Here, we show that the balance of hydrogen-bonded contact ion pairs (CIP) and solvent-separated (SIP) ion pairs in protic ionic liquids (PILs) and in their mixtures with water can be well understood by a combination of far-infrared (FIR) and mid-infrared (MIR) spectroscopy, density functional theory (DFT) calculations of PIL/water aggregates, and molecular dynamics (MD) simulations of PIL/water mixtures. This combined approach is applied to mixtures of triethylammonium methanesulfonate [Et3NH][MeSO3] with water. It is shown that ion speciation in this mixture depends on three parameters: the relative hydrogen bond acceptor strength of the counter ion and the molecular solvent, the solvent concentration, and the temperature. For selected PIL/water mixtures, the equilibrium constants for CIPs and SIPs were determined as a function of the solvent content and temperature. Finally, for the studied PIL/water mixtures, the transition from CIPs to SIPs could be understood on enthalpic and entropic grounds. A detailed picture of this interconversion process could be described at the molecular level by means of MD simulations. In addition, the concentration dependence of ion pair formation can be well understood with help of a simplified "cartoon-like" statistical model describing hydrogen bond redistribution.
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Affiliation(s)
- Benjamin Golub
- Institut für Chemie, Abteilung Physikalische und Theoretische Chemie, Universität Rostock, Albert-Einstein-Straße 21, D-18059 Rostock, Germany
| | - Koichi Fumino
- Institut für Chemie, Abteilung Physikalische und Theoretische Chemie, Universität Rostock, Dr.-Lorenz-Weg 2, D-18059 Rostock, Germany
| | - Peter Stange
- Institut für Chemie, Abteilung Physikalische und Theoretische Chemie, Universität Rostock, Dr.-Lorenz-Weg 2, D-18059 Rostock, Germany
| | - Verlaine Fossog
- Transfercenter Sustainable Electrochemistry, Saarland University and KIST Europe, D-66123 Saarbrücken, Germany
| | - Rolf Hempelmann
- Transfercenter Sustainable Electrochemistry, Saarland University and KIST Europe, D-66123 Saarbrücken, Germany
| | - Daniel Ondo
- Department of Physical Chemistry, University of Chemistry and Technology, Technicka 5, CZ-166 28 Prague 6, Czech Republic
| | - Dietmar Paschek
- Institut für Chemie, Abteilung Physikalische und Theoretische Chemie, Universität Rostock, Albert-Einstein-Straße 21, D-18059 Rostock, Germany
| | - Ralf Ludwig
- Institut für Chemie, Abteilung Physikalische und Theoretische Chemie, Universität Rostock, Dr.-Lorenz-Weg 2, D-18059 Rostock, Germany.,Leibniz Institut für Katalyse an der Universität Rostock, Albert-Einstein-Straße 29a, D-18059 Rostock, Germany
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112
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Hakim L, Ishii Y, Matubayasi N. Spatial-Decomposition Analysis of Electrical Conductivity in Mixtures of Ionic Liquid and Sodium Salt for Sodium-Ion Battery Electrolytes. J Phys Chem B 2021; 125:3374-3385. [PMID: 33759521 DOI: 10.1021/acs.jpcb.1c00372] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Ionic liquid (IL)-based electrolytes are a promising material for the development of sodium-ion batteries, and their performance can be quantified by electrical conductivity. In this highly concentrated ionic system, the correlated motions of ion pairs are influential on the ionic transport properties. Herein, all-atom analyses are conducted through molecular dynamics simulations to bridge the macroscopically observable electrical conductivity with the molecular pictures of correlated motion of ion pairs. The analysis is applied to three mixtures of IL with sodium salt that are relevant to the electrolyte for a sodium-ion battery: [1-ethyl-3-methylimidazolium, Na][bis(fluorosulfonyl)amide] ([C2C1im, Na][FSA]), [N-methyl-N-propylpyrrolidinium, Na][FSA] ([C3C1pyrr, Na][FSA]), and [K, Na][FSA]. The computational results on electrical conductivities are in agreement with the experimental reports, and their dependency on temperature and sodium-ion composition is reproduced well. The overall contributions from cross-correlated motions are found to be negative in all the IL mixtures; thus, the total conductivities are less than their Nernst-Einstein estimates. The spatial view of cross-correlated motions is further obtained by decomposing the time correlation functions of velocities according to the distances between ion pairs. It is observed that ion pairs are moving in the same direction for ∼0.3 ps when they were initially within the first coordination shell, followed by motions toward opposite directions. The cross-correlation terms are also dissected into local and nonlocal components, and it is commonly seen for all the ion pairs that the local component is negative for cation-anion pairs and is positive for cation-cation and anion-anion pairs. The motions of ion pairs are accompanied by a "backflow" that manifests in the form of the nonlocal component whose sign is opposite to the corresponding local component. In fact, the contributions of the correlated motions of ions to the electrical conductivity are not localized to contact pairs and extend spatially beyond the first coordination shell of the cation-anion pairs.
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Affiliation(s)
- Lukman Hakim
- Elements Strategy Initiatives for Catalysts and Batteries, Kyoto University, Katsura, Kyoto 615-8520, Japan.,Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.,Department of Chemistry, Faculty of Mathematics and Natural Science, Brawijaya University, Malang 65145, Indonesia
| | - Yoshiki Ishii
- Elements Strategy Initiatives for Catalysts and Batteries, Kyoto University, Katsura, Kyoto 615-8520, Japan.,Graduate School of Simulation Studies, University of Hyogo, Kobe, Hyogo 650-0047, Japan
| | - Nobuyuki Matubayasi
- Elements Strategy Initiatives for Catalysts and Batteries, Kyoto University, Katsura, Kyoto 615-8520, Japan.,Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
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113
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Srivastava AK, Kumar A, Misra N. Superhalogens as Building Blocks of Ionic Liquids. J Phys Chem A 2021; 125:2146-2153. [PMID: 33666417 DOI: 10.1021/acs.jpca.1c00599] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ionic liquids (ILs) are composed of large asymmetric organic cations with a wide range of anions. The simple anions, e.g., halogen, result in less stable ILs, and therefore, ILs generally consist of complex anions such as BF4 and PF6. These anions coincidently belong to a special class known as superhalogen. This prompted us to enquire whether the concept of superhalogen can be exploited to design new ILs. We study the complexes of 1-butyl-3-methylimidazolium (BMIM) cation and typical superhalogen (X) anions such as LiF2, BeF3, BO2, NO3, BF4, and PF6 including Cl using density functional theory and the quantum theory of atoms in molecule. Our ωB97XD/6-311++G(d,p) calculations suggest that the BMIM-X complexes are stable in which the charge transfer of 0.90-0.97 e takes place from BMIM to X. The charge-transferred tends to delocalize as the size of X increases. These complexes are stabilized by several ionic and/or covalent intramolecular interactions (H-bonds). The BMIM-X complexes prefer to dissociate into ionic fragments (BMIM+ + X-) than neutral fragments (BMIM + X). The dissociation energy and energy gap of BMIM-X complexes are closely related to the electron affinity of superhalogens (X). These findings not only reveal the superhalogens as building blocks of ILs but also suggest the design of highly stable ILs by employing the superhalogens with higher electron affinities.
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Affiliation(s)
- Ambrish Kumar Srivastava
- Department of Physics, Deen Dayal Upadhyaya Gorakhpur University, Civil Lines, Gorakhpur 273009, Uttar Pradesh, India
| | - Abhishek Kumar
- Department of Physics, University of Lucknow, University Road, Lucknow 226007, Uttar Pradesh, India
| | - Neeraj Misra
- Department of Physics, University of Lucknow, University Road, Lucknow 226007, Uttar Pradesh, India
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