The Experts below are selected from a list of 234 Experts worldwide ranked by ideXlab platform
Andreas Heuer - One of the best experts on this subject based on the ideXlab platform.
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simulatIon study of the lithium Ion Transport Mechanism in ternary polymer electrolytes the critical role of the segmental mobility
Journal of Physical Chemistry B, 2014Co-Authors: Diddo Diddens, Andreas HeuerAbstract:We present an extensive molecular dynamics (MD) simulatIon study of the lithium Ion Transport in ternary polymer electrolytes consisting of poly(ethylene oxide) (PEO), lithium-bis(trifluoromethane)sulfonimide (LiTFSI), and the Ionic liquid N-methyl-N-propylpyrrolidinium bis(trifluoromethane)sulfonimide (PYR13TFSI). In particular, we focus on two different strategies by which the ternary electrolytes can be devised, namely by (a) adding the Ionic liquid to PEO20LiTFSI and (b) substituting the PEO chains in PEO20LiTFSI by the Ionic liquid. To grasp the changes of the overall lithium Transport Mechanism, we employ an analytical, Rouse-based catIon Transport model (Maitra et al. Phys. Rev. Lett. 2007, 98, 227802), which has originally been devised for binary PEO-based electrolytes. This model distinguishes three different microscopic Transport Mechanisms, each quantified by an individual time scale. In the course of our analysis, we extend this mathematical descriptIon to account for an entirely new Transport...
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lithium Ion Transport Mechanism in ternary polymer electrolyte Ionic liquid mixtures a molecular dynamics simulatIon study
ACS Macro Letters, 2013Co-Authors: Diddo Diddens, Andreas HeuerAbstract:The lithium Transport Mechanism in ternary polymer electrolytes, consisting of PEO20LiTFSI and various fractIons of the Ionic liquid PYR13TFSI, is investigated by means of MD simulatIons. This is motivated by recent experimental findings (Passerini et al. Electrochim. Acta2012, 86, 330), which demonstrated that these materials display an enhanced lithium mobility relative to their binary counterpart PEO20LiTFSI. In order to grasp the underlying microscopic scenario giving rise to these observatIons, we employ an analytical, Rouse-based catIon Transport model (Maitra et al. Phys. Rev. Lett.2007, 98, 227802), which has originally been devised for conventIonal polymer electrolytes. This model describes the catIon Transport via three different Mechanisms, each characterized by an individual time scale. It turns out that also in the ternary electrolytes essentially all lithium Ions are coordinated by PEO chains, thus, ruling out a Transport Mechanism enhanced by the presence of Ionic-liquid molecules. Rather, ...
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lithium Ion Transport Mechanism in ternary polymer electrolyte Ionic liquid mixtures a molecular dynamics simulatIon study
arXiv: Soft Condensed Matter, 2012Co-Authors: Diddo Diddens, Andreas HeuerAbstract:The lithium Transport Mechanism in ternary polymer electrolytes, consisting of PEO/LiTFSI and various fractIons of the Ionic liquid N-methyl-N-propylpyrrolidinium bis(trifluoromethane)sulfonimide, are investigated by means of MD simulatIons. This is motivated by recent experimental findings [Passerini et al., Electrochim. Acta 2012, 86, 330-338], which demonstrated that these materials display an enhanced lithium mobility relative to their binary counterpart PEO/LiTFSI. In order to grasp the underlying microscopic scenario giving rise to these observatIons, we employ an analytical, Rouse-based catIon Transport model [Maitra at al., PRL 2007, 98, 227802], which has originally been devised for conventIonal polymer electrolytes. This model describes the catIon Transport via three different Mechanisms, each characterized by an individual time scale. It turns out that also in the ternary electrolytes essentially all lithium Ions are coordinated by PEO chains, thus ruling out a Transport Mechanism enhanced by the presence of Ionic-liquid molecules. Rather, the plasticizing effect of the Ionic liquid contributes to the increased lithium mobility by enhancing the dynamics of the PEO chains and consequently also the motIon of the attached Ions. AdditIonal focus is laid on the predictIon of lithium diffusIon coefficients from the simulatIon data for various chain lengths and the comparison with experimental data, thus demonstrating the broad applicability of our approach.
Diddo Diddens - One of the best experts on this subject based on the ideXlab platform.
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simulatIon study of the lithium Ion Transport Mechanism in ternary polymer electrolytes the critical role of the segmental mobility
Journal of Physical Chemistry B, 2014Co-Authors: Diddo Diddens, Andreas HeuerAbstract:We present an extensive molecular dynamics (MD) simulatIon study of the lithium Ion Transport in ternary polymer electrolytes consisting of poly(ethylene oxide) (PEO), lithium-bis(trifluoromethane)sulfonimide (LiTFSI), and the Ionic liquid N-methyl-N-propylpyrrolidinium bis(trifluoromethane)sulfonimide (PYR13TFSI). In particular, we focus on two different strategies by which the ternary electrolytes can be devised, namely by (a) adding the Ionic liquid to PEO20LiTFSI and (b) substituting the PEO chains in PEO20LiTFSI by the Ionic liquid. To grasp the changes of the overall lithium Transport Mechanism, we employ an analytical, Rouse-based catIon Transport model (Maitra et al. Phys. Rev. Lett. 2007, 98, 227802), which has originally been devised for binary PEO-based electrolytes. This model distinguishes three different microscopic Transport Mechanisms, each quantified by an individual time scale. In the course of our analysis, we extend this mathematical descriptIon to account for an entirely new Transport...
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lithium Ion Transport Mechanism in ternary polymer electrolyte Ionic liquid mixtures a molecular dynamics simulatIon study
ACS Macro Letters, 2013Co-Authors: Diddo Diddens, Andreas HeuerAbstract:The lithium Transport Mechanism in ternary polymer electrolytes, consisting of PEO20LiTFSI and various fractIons of the Ionic liquid PYR13TFSI, is investigated by means of MD simulatIons. This is motivated by recent experimental findings (Passerini et al. Electrochim. Acta2012, 86, 330), which demonstrated that these materials display an enhanced lithium mobility relative to their binary counterpart PEO20LiTFSI. In order to grasp the underlying microscopic scenario giving rise to these observatIons, we employ an analytical, Rouse-based catIon Transport model (Maitra et al. Phys. Rev. Lett.2007, 98, 227802), which has originally been devised for conventIonal polymer electrolytes. This model describes the catIon Transport via three different Mechanisms, each characterized by an individual time scale. It turns out that also in the ternary electrolytes essentially all lithium Ions are coordinated by PEO chains, thus, ruling out a Transport Mechanism enhanced by the presence of Ionic-liquid molecules. Rather, ...
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lithium Ion Transport Mechanism in ternary polymer electrolyte Ionic liquid mixtures a molecular dynamics simulatIon study
arXiv: Soft Condensed Matter, 2012Co-Authors: Diddo Diddens, Andreas HeuerAbstract:The lithium Transport Mechanism in ternary polymer electrolytes, consisting of PEO/LiTFSI and various fractIons of the Ionic liquid N-methyl-N-propylpyrrolidinium bis(trifluoromethane)sulfonimide, are investigated by means of MD simulatIons. This is motivated by recent experimental findings [Passerini et al., Electrochim. Acta 2012, 86, 330-338], which demonstrated that these materials display an enhanced lithium mobility relative to their binary counterpart PEO/LiTFSI. In order to grasp the underlying microscopic scenario giving rise to these observatIons, we employ an analytical, Rouse-based catIon Transport model [Maitra at al., PRL 2007, 98, 227802], which has originally been devised for conventIonal polymer electrolytes. This model describes the catIon Transport via three different Mechanisms, each characterized by an individual time scale. It turns out that also in the ternary electrolytes essentially all lithium Ions are coordinated by PEO chains, thus ruling out a Transport Mechanism enhanced by the presence of Ionic-liquid molecules. Rather, the plasticizing effect of the Ionic liquid contributes to the increased lithium mobility by enhancing the dynamics of the PEO chains and consequently also the motIon of the attached Ions. AdditIonal focus is laid on the predictIon of lithium diffusIon coefficients from the simulatIon data for various chain lengths and the comparison with experimental data, thus demonstrating the broad applicability of our approach.
Aninda J Bhattacharyya - One of the best experts on this subject based on the ideXlab platform.
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Time–Temperature Scaling and Dielectric Modeling of Conductivity Spectra of Single-Ion Conducting Liquid Dendrimer Electrolytes
2018Co-Authors: Sudeshna Sen, Maria Forsyth, Haijin Zhu, Aninda J BhattacharyyaAbstract:We discuss here the time–temperature scaling and dielectric modeling of the variatIon of single-Ion conductivity with frequency of first generatIon (G1) liquid dendrimer electrolyte, viz., Poly(propyl ether imine) (PETIM):Li-salt. The PETIM:Li-salt electrolyte exhibits a catIon/anIon transference number close to unity in the liquid state. On switching from an ester (G1-COOR) to cyano (G1-CN) peripheral group, keeping constant the linker (ether) and branching groups (amine), an interesting transformatIon from catIonic (t+ ∼1) to anIonic conductor (t– ∼1) takes place. The switch in the nature of the predominant charge carrier is directly related to the change in the magnitude of anIon diffusIon (D–), which increases by 1 order of magnitude from D– = 1.1 × 10–12 m2 s–1 (at 30 °C) in G1-COOR to D– = 1.3 × 10–11 m2 s–1 (at 30 °C) in G1-CN. This intriguing Ion Transport Mechanism is probed comprehensively using ac-impedance spectroscopy. The frequency dependent Ionic conductivity of G1-CN/G1-COOR, comprised of distinct frequency regimes, is analyzed using the time–temperature superpositIon scaling principle (TTSP) based on Summerfield and Baranovski scaling methods. To gain insight into the electrical polarizatIon (EP) phenomenon, the relevant frequency regime is converted from conductivity to dielectric versus frequency. The dielectric versus frequency data is modeled using Macdonald and Coelho. The combined approach of TTSP and dielectric modeling provide explicitly the extent of the influence of Ion–dendrimer, Ion–Ion interactIons, and also the mobile charge carrier density on the effective Ion Transport in the homogeneous single-Ion conducting dendrimer electrolytes. The combined analysis suggests that Ion Transport in PETIM-COOR is only due to enhanced Ion mobility, whereas in PETIM-CN it is due to both mobile charge carrier concentratIon and Ion mobility. To the best of our knowledge, the scaling and modeling approaches employed here constitute a rare example for validatIon of such concepts in the context of dendrimer electrolytes
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Ion Transport Mechanism of a gel electrolyte comprising a salt in binary plastic crystalline mixtures confined inside a polymer network
Journal of Physical Chemistry B, 2016Co-Authors: Sudeshna Sen, Sneha Malunavar, Aninda J BhattacharyyaAbstract:We discuss here the Ion Transport Mechanism of a gel electrolyte comprising lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) solvated by two plastic crystalline solvents, one a solid (succinonitrile, abbreviated as SN) and another (a room temperature Ionic liquid) (1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide, (abbreviated as IL) confined inside a linear network of poly(methyl methacrylate) (PMMA). The concentratIon of the IL component (x) determines the physical properties of the unconfined electrolyte (i.e., SN1–xILx-LiTFSI) and when confined inside the polymer network (GPE-x). The extent of disorder in the SN1–xILx-LiTFSI and the GPE-x electrolytes is enhanced compared to both the bare SN-LiTFSI and IL-LiTFSI electrolytes. The enhanced disordering in the plastic phase alters both the local Ion environment and viscosity. These changes strongly influence the Ion mobility and nature of predominant charge carriers and thus the Ion conductIon Mechanism in SN1–xILx-LiTFSI and GPE-x. Th...
Naoki Hasegawa - One of the best experts on this subject based on the ideXlab platform.
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lithium Ion conductivity of polymers containing n phenyl 2 6 dimethoxybenzamide framework in their side chains possible role of bond rotatIon in polymer side chain substituents for efficient Ion Transport
Solid State Ionics, 2016Co-Authors: Hiroaki Shimomoto, Takahiro Uegaito, Shohei Yabuki, Soichiro Teratani, Tomomichi Itoh, Eiji Ihara, Naohiro Hoshikawa, Akihiko Koiwai, Naoki HasegawaAbstract:Abstract A new carbon–carbon main chain polymer with N -phenyl-2,6-dimethoxybenzamide on its each main chain carbon atom is prepared by Pd-initiated polymerizatIon of diazoacetate containing the benzamide group, and the Li Ion conductivity of the polymer doped with lithium bis(trifluoromethylsulfonyl)imide is evaluated along with its vinyl polymer counterparts with the same benzamide substituent. Although the expected high Ion conductivity at low temperatures derived from a unique Ion Transport Mechanism based on the bond rotatIon in the benzamide moiety reported in a literature is not observed, it is revealed that the dense packing of the benzamide group along the polymer main chain results in the enhanced Ion conductivity. In additIon, investigatIon of the correlatIon between Ion conductivity and glass transitIon temperature of these solid polymer electrolytes (SPEs) reveals that other Ion Transport Mechanism would operate in the benzamide containing SPEs than that derived from segmental motIon of polymer chains observed in PEO-based SPEs.
Shujahadeen B Aziz - One of the best experts on this subject based on the ideXlab platform.
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Ion Transport study in cs poz based polymer membrane electrolytes using trukhan model
International Journal of Molecular Sciences, 2019Co-Authors: Shujahadeen B Aziz, Wrya O Karim, M A Brza, Rebar T Abdulwahid, Salah R Saeed, Shakhawan Alzangana, M F Z KadirAbstract:In this work, analysis of Ion Transport parameters of polymer blend electrolytes incorporated with magnesium trifluoromethanesulfonate (Mg(CF3SO3)2) was carried out by employing the Trukhan model. A solutIon cast technique was used to obtain the polymer blend electrolytes composed of chitosan (CS) and poly (2-ethyl-2-oxazoline) (POZ). From X-ray diffractIon (XRD) patterns, improvement in amorphous phase for the blend samples has been observed in comparison to the pure state of CS. From impedance plot, bulk resistance (Rb) was found to decrease with increasing temperature. Based on direct current (DC) conductivity (σdc) patterns, consideratIons on the Ion Transport models of Arrhenius and Vogel–Tammann–Fulcher (VTF) were given. Analysis of the dielectric properties was carried out at different temperatures and the obtained results were linked to the Ion Transport Mechanism. It is demonstrated in the real part of electrical modulus that chitosan-salt systems are extremely capacitive. The asymmetric peak of the imaginary part (Mi) of electric modulus indicated that there is non-Debye type of relaxatIon for Ions. From frequency dependence of dielectric loss (e″) and the imaginary part (Mi) of electric modulus, suitable coupling among polymer segmental and Ionic motIons was identified. Two techniques were used to analyze the viscoelastic relaxatIon dynamic of Ions. The Trukhan model was used to determine the diffusIon coefficient (D) by using the frequency related to peak frequencies and loss tangent maximum heights (tanδmax). The Einstein–Nernst equatIon was applied to determine the carrier number density (n) and mobility. The Ion Transport parameters, such as D, n and mobility (μ), at room temperature, were found to be 4 × 10−5 cm2/s, 3.4 × 1015 cm−3, and 1.2 × 10−4 cm2/Vs, respectively. Finally, it was shown that an increase in temperature can also cause these parameters to increase.
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role of Ion dissociatIon on dc conductivity and silver nanoparticle formatIon in pva agnt based polymer electrolytes deep insights to Ion Transport Mechanism
Polymers, 2017Co-Authors: Shujahadeen B Aziz, Ranjdar M Abdullah, Mariwan A Rasheed, Hameed M AhmedAbstract:In this study, the role of Ion dissociatIon on formatIon of silver nanoparticle and DC conductivityin PVA:AgNO3 based solid polymer electrolyte has been discussed in detail. Samples of silver Ion conducting solid polymer electrolyte were prepared by using solutIon cast technique. AbsorptIon spectroscopy in the ultraviolet–visible (UV–Vis) spectral regIon was used to investigate the formatIon of silver nanoparticles. Broad and sharp peaks due to plasmonic silver nanoparticles subjected to Ion dissociatIon have been observed. The influence of dielectric constant on the intensity of surface plasmonic resonance (SPR) peaks attributed to silver nanoparticles was discussed. From impedance plots, the diameter of high frequency semicircle was found to be decreased with increasing salt concentratIon. The DC conductivity in relatIon to the dielectric constant was also explained. From the AC conductivity spectra, the dc conductivity was estimated to be close to that calculated from the bulk resistance. The temperature dependence of the DC conductivity was studied and found to follow Arrhenius equatIon within two distinguished regIons. The AC conductivity at different temperatures has been studied to comprehend the Ion conductIon Mechanism. The AC conductivity against frequency was found to obey the universal power law of Jonscher. Three distinct regIons were recognized from the spectra of AC conductivity. The frequency exponent (S) was calculated for the dispersive regIon of the measured AC conductivity spectra. Various models were discussed to explain the behavior of S value with temperature. The behavior of S value with temperature was then used to interpret the DC conductivity pattern against 1000/T. Finally, from the comparison of calculated activatIon energy (Ea) and maximum barrier height (Wm), deep insights into Ion conductIon Mechanism could be grasped.
