Symposium Organizers
Rico E. Del Sesto, Los Alamos National Laboratory
Sheng Dai, Oak Ridge National Laboratory
Robin D. Rogers, The University of Alabama
Yukihiro Yoshida, Meijo University
Tuesday PM, April 02, 2013
Marriott Marquis, Golden Gate Level, Salon C2
2:30 AM - *VV2.01
Recent Progress in KOEIrsquo;s Ionic Liquid
Toshio Sumida 1 Mayumi Nishida 1
1Koei Chemical Company Tokyo Japan
Show AbstractKOEI CHMICAL is an expert in manufacturing chemical products containing nitrogen atom such as pyridines, pyrazines and amines. Using such products as a key component, we synthesized phase transfer catalysts and launched them into the market in 1982.
In 2000, we started the research of ionic liquids. Since then, the product line-up has been increasing up to over 500 chemicals and we named our ionic liquids ‘KOELIQ&’.
Ionic liquids have unique physical properties, such as low volatility, high electrical conductivity, high electrochemical stability (wide electrochemical window), high thermal conductivity as well as good thermal stability. Such unique properties of ionic liquids make them attractive in various fields of industrial applications. For example, ionic liquids are used as electrolytes, lubricants, antistatic agents, thermal energy storage materials and so on. They are also used in industrial processes for separation, purification, degradation and recovery.
In this presentation, we would like to focus on following three topics.
1. Hard coating agents with antistatic performance
We developed hard coating agents for PET films. In this hard coating agent, ionic liquids were used as an antistatic agent.
2. Recovery of cellulose from biomass
The relationship between structure of ionic liquids and solubility of cellulose in ionic liquid was studied.
3. Recovery of MMA from PMMA
PMMA degradation experiments were conducted in ionic liquids followed by distillation of MMA. We found particular ionic liquids which work as heat media for this degradation process.
3:00 AM - VV2.02
Inkjet Printing of Ionic Liquids for the Formation of Surface Structures on Biopolymer Substrates
Kurt D Sweely 1 Luke M. Haverhals 1 Matthew P. Foley 1 Eva K. Brown 1 Hugh C. De Long 2 Paul C. Trulove 1
1United States Naval Academy Annapolis USA2Air Force Office of Scientific Resesarch Arlington USA
Show AbstractInkjet printing has become an increasingly popular tool for materials science research due to its ability to reliably and inexpensively create devices with a wide variety of applications and functionalities. Recent studies have utilized inkjet printing for the construction of inexpensive devices using “ink” solutions containing various materials of interest (magnetic, sensing, electronic)1,2,3.
Ionic liquid (IL) utilization in inkjet printing presents an exciting and promising avenue of research due to its unique properties, as some ILs can be used to solubilize biopolymers (such as cellulose and silk)4. When paired with inkjet printing, these ILs and materials of interest allow for the controllable construction of a wide variety of devices and structures. To further enhance the reliability and control over the inkjet printing process, raster image processing (RIP) software is used to gain complete control over the printing process, most notably droplet size and print quality. Using inkjet printing of ILs enhanced by RIP software, this research demonstrates the capacity to create robust materials with desireable physical and chemical properties.
References
1. Delaney, J. T., Jr.; Smith, P. J.; Schubert, U. S. Inkjet Printing of Proteins. Soft Matter, 2009, 24, 4866.
2. Singh, M.; Haverinen, H. M.; Dhagat, P.; Jabbour, G. E. Inkjet Printing - Process and Its Applications. Adv. Materials, 2010, 22, 673.
3. Hu, C.; Bai, X.; Wang, Y.; Jin, W.; Zhang, X.; Hu, S. Inkjet Printing of Nanoporous Gold Electrode Arrays. Anal. Chem. 2012, 84, 3745.
4. Swatloski, R. P.; Spear, S. K.; Holbrey, J. D.; Rogers, R. D. Dissolution of Cellulose with Ionic Liquids. J. Am. Chem. Soc., 2002, 18, 4974.
3:15 AM - VV2.03
Electrospinning of Biopolymers from Ionic Liquid Co-solvent Systems
Eva Kathryn Brown 1 Luke M. Haverhals 1 Kurt D. Sweely 1 Matthew P. Foley 1 Hugh C. De Long 2 Paul C. Trulove 1
1United States Naval Academy Annapolis USA2Air Force Office of Scientific Research Arlington USA
Show AbstractElectrospinning is a technique commonly employed to obtain high surface area micro to nano sized fibers1. Of particular interest are electrospun natural fibers, such as cellulose, its derivatives or combinations thereof, with high biocompatibility allowing for a variety of applications2. Unfortunately, cellulose is insoluble in common solvents due to its natural recalcitrance arising from an exceptionally strong hydrogen bonding network leading to high-crystallinity. Currently, processing techniques such as wet or dry-wet spinning3 as well as electrospinning1-5 have been investigated with known cellulose solvents (N-methyl-morpholine N-oxide/water3,4, salt/solvent systems such as lithium chloride/dimethyl acetamide3,4 or ethylene diamine/potassium thiocyanate3, ionic liquids, ILs1 and IL/dimethylsulfoxide systems5).
Among the known solvent systems for cellulose dissolution, ILs offer certain advantages over other solvents such as high biopolymer solubility and a simple dissolution process requiring only mild heating and stirring. In the current work, solutions of cellulose dissolved in an IL, 1-ethyl-3-methylimidazolium (EMIAc), and a molecular co-solvent, were investigated for their ability to form spinnable fibers at room temperature without the use of controlled humidity or coagulation bath. The impact of IL and solvent concentration and composition on polymer melt rheology as well as fiber formation and characteristics has been investigated. Introduction and incorporation of nano-materials into dopes was also explored.
References
1. Quan, S.; Kang, S.; Chin, I. Characterization of cellulose fibers electrospun using ionic liquid. Cellulose, 2010, 17, 223.
2. Freire, M. G.; Reles, A. R. R.; Ferreira, R. A. S.; Carlos, L. D.; Lopes-de-Silva, J. A.; Coutinho, J. A. P. Electrospun nanosized cellulose fibers using ionic liquids at room temperature. Green Chemistry, 2011, 13, 3173.
3. Kim, C.; Kim, D.; Kang, S.; Marquez, M.; Joo, Y. L. Structural studies of electrospun cellulose nanofibers. Polymer, 2006, 47, 5097.
4. Frey, M. W. Electrospinning cellulose and cellulose derivatives. Polymer Reviews, 2008, 48, 378.
5. Xu, S.; Zhang, J.; He, A.; Li, J.; Zhang, H.; Han, C. C. Electrospinning of native cellulose from nonvolatile solvent system. Polymer, 2008, 49, 2911.
3:30 AM - *VV2.04
Biomass Separations with Ionic Liquids
Wesley Henderson 1 Xinglian Geng 1 Ezinne Achinivu 1
1North Carolina State University Raleigh USA
Show AbstractIonic liquids (ILs) represent powerful media for the separation and processing of biomass components. This separation is strongly influenced by the structure of the IL ions, as well as other process variables. Unfortunately, ILs are quite costly and only a limited number of ILs are known to be effective at polysaccharide dissolution. Thus, the properties of these ILs cannot be readily tailored for process optimization. Several alternative approaches to "traditional" processing of biomass with ILs will be presented—these include the dissolution of polysaccharides with solvent-IL mixtures, regeneration of the polysaccharides with alterative nonsolvents (to water) and the dissolution of lignin (rather than the polysaccharides) with ILs. Correlations will be provided between ion structure and IL properties...and the impact of these on biomass processing. These methods may well be viable means to process a wide variety of lignocellulosic biomass substrates.
4:30 AM - *VV2.05
Deep Eutectic Solvents Playing Multiple Roles in the Synthesis of Hierarchical Monolithic Carbons
Francisco del Monte 1 Maria C. Gutierrez 1 Julian Patino 1 Elena Posada 1 M. Nieves Lopez-Salas 1 Daniel Carriazo 1 M. Luisa Ferrer 1
1ICMM-CSIC Madrid Spain
Show AbstractThere are certain properties of ionic liquids (ILs) such as the excellent solubility of number of substances, their good thermal stability or their intrinsic ionic character that make them especially suitable for use as media for the preparation of materials. In these cases, ILs can act as a regular solvent, as a solvent which shows a more or less controlled structure directing effect or even as a molecular precursor with a well-defined composition, structure, and reactivity (the termed next generation “all-in-one” solvent-template-reactant ILs). Within this context, ILs have also emerged as an interesting media to carry out different polymerizations. However, the replacement is yet difficult to justify in economical terms because of the cost of common ILs unless the resulting polymer offer certain specific properties attainable only because of their use. A related class of ILs named deep-eutectic solvents (DESs) may offer an interesting alternative. DESs are obtained by complexion of quaternary ammonium salts with hydrogen-bond donors.[1] DESs share many characteristics of conventional ILs (e.g. nonreactive with water, nonvolatile and biodegradable) while offering certain advantages (e.g. high purity and low cost, among the most significant). Our work has been lately focussed on the use of DESs playing multiple roles (e.g. reaction medium, monomer precursors and even structure directing agents) in polycondensation reactions. Thus, after thermal treatments at 800°C, the resulting hierarchical carbon monoliths exhibited interesting properties both as 3D electrodes in supercapacitors and for CO2 adsorption in gas separation processes.[2]
Bibliography:
1. Abbott, A. P.; Capper, G.; Davies, D. L.; Rasheed, R. K.; Tambyrajah, V. Chem. Commun. 2003, 70.
2. (a) Gutierrez, M. C.; Rubio, F.; del Monte, F. Chem. Mater. 2010, 22, 2711-2719. (b) Carriazo, D.; Gutierrez, M. C.; Ferrer, M. L.; del Monte, F. Chem. Mater. 2010, 22, 6146-6152. (c) Gutierrez, M. C.; Carriazo, D.; Ania, C.; Parra, J.; Ferrer, M. L.; del Monte, F. Energy Environ. Sci. 2011, 4, 3535-3544. (d) Gutierrez, M. C.; Carriazo, D.; Tamayo, A.; Jiménez, R.; Picoacute;, F.; Rojo, J. M.; Ferrer, M. L.; del Monte, F. Chem.-A Eur. J. 2011, 17, 10533-10537. (e) Carriazo, D.; Gutierrez, M. C.; Picoacute;, P.; Rojo, J. M.; Fierro, J. L. G.; Ferrer, M. L.; del Monte, F., ChemSusChem 2012, 5, 1405-1409. (f) Patiño, J.; Gutierrez, M. C.; Carriazo, D.; Ania, C.; Parra, J.; Ferrer, M. L.; del Monte, F. Energy Environ. Sci. 2012, 5, 8699-8707
5:00 AM - VV2.06
Carbon Dioxide Capture and Electro-reduction in Imidazolium Ionic Liquids at Metal Electrodes
John D. Watkins 1 Andrew B Bocarsly 1
1Princeton University Princeton USA
Show AbstractCarbon dioxide is a well known atmospheric pollutant and combustion by-product. A possible solution for its mitigation would involve the simultaneous sequestration and conversion of carbon dioxide to value added products such as fuels or common chemical starting materials. For this approach not only is potentially hazardous carbon dioxide removed from the environment, but there is also a potential for solving of the problem of decreasing reserves of fossil fuels. In this way, room temperature ionic liquids (RTILs) represent a potentially ideal medium for this approach. They are known to have a high capacity and large selectivity for carbon dioxide capture as well as being inherently conductive, making them well suited for the direct electro-reduction of CO2. The nature of the ionic liquid structure, however, allows many millions of potential candidates to be readily available and as such a targeted approach for optimisation of physical and electrochemical properties is important.
Thus far, the electrochemical reduction of carbon dioxide in RTILs has focused on the use of 1-Ethyl-3-methylimidazolium tetrafluoroborate [1] but this ionic liquid is far from ideal in terms of carbon dioxide capture and electro-reduction. 1-Ethyl-3-methylimidazolium acetate by contrast is known to facilitate the storage of far more carbon dioxide but becomes solid and unusable in its neat form when saturated with CO2.[2]
In this study, an alternative electrolyte, 1-ethyl-3-methylimidazolium trifluoroacetate was explored for carbon dioxide reduction under both neat and co-solvated conditions. This ionic liquid was chosen due to its excellent balance of relative physical and electrochemical properties including; a low viscosity, high conductivity, high CO2 content and large cathodic electrochemical window in which the liquid is not itself reduced. It was found that by using heavy post-transition metal electrodes known to facilitate the direct reduction of carbon dioxide to formate, high yields of formate were achievable (10-20 mM) with analysis by electrochemical methods, 1H and 2H NMR spectroscopy.
[1] “Ionic Liquid-Mediated Selective Conversion of CO2 to CO at Low Overpotentials”, Rosen et al. 2011, Science, 334, 643-644.
[2] “Demonstration of Chemisorption of Carbon Dioxide in 1,3-Dialkylimidazolium Acetate Ionic Liquids”, Garau et al. 2011, Angew. Chem. Int. Ed. 50, 12024-12026.
5:15 AM - VV2.07
The Development of Advanced Liquid Composite Materials by Controlling Stabilization of Nanoparticles in Ionic Liquids
Robin D Rogers 1 Parker D McCrary 1
1The University of Alabama Tuscaloosa USA
Show AbstractIonic liquids (ILs) have been utilized to incorporate a variety of nanomaterials, such as nanoparticles, graphene, clays, drugs, etc. The dispersed or exfoliated nanomaterials can be effectively stabilized in an IL through specific and tunable surface interactions. Typically, the added particles are incorporated for a particular task, such as catalysis, drug delivery, or as an energetic additive within an IL that is designed to be merely a solvent or a carrier. However, recent results suggest that a synergistic effect is possible through the design of surface interactions to improve the deficient properties of either material. By selecting ILs and nanomaterials with complementary functions, a single, composite material can be created. Due to the applicability of both ILs and nanomaterials, a wide range of potential composite materials exist from energetic materials to drug delivery. Here we demonstrate how ILs and nanomaterials, with varying compositions, can be utilized together as a single composite liquid material with improved and synergistic properties through the design and incorporation of specific surface interactions.
5:30 AM - *VV2.08
Microscopic Insights of Ionic Liquids in Gas Separations and Energy Storage
De-en Jiang 1
1Oak Ridge National Lab Oak Ridge USA
Show AbstractIonic liquids are a unique medium for gas separations and energy storage. For important separations such as capture of carbon dioxide from flue gas, ionic liquids can be used for either physisorption or chemisorption of carbon dioxide. In the case of chemisorption, we find that superbase derived ionic liquids and phosphonium-based ionic liquids can absorb carbon dioxide at 1:1 stoichiometry through reaction of the anion with carbon dioxide. The heat of absorption is shown to be tunable and correlated with the atomic charges on the anion, thereby providing a handle to achieve optimal interaction. For physisorption, we find that the tetracycanoborate anion is unique in yielding ionic liquids with high solubility for carbon dioxide; this is due to the weak interaction between the tetracycanoborate anion and the cation which allows easy creation of cavity for carbon dioxide inside the ionic liquid. Ionic liquids are also a good electrolyte for supercapacitor applications where symmetric porous carbon electrodes are used. Here we find that the surface-area-normalized capacitance oscillates with the pore size when an ionic liquid is used as an electrolyte; we attribute this behavior to the interference of the electrical double layers of ionic liquids. These findings highlight the unique opportunity and physicochemical properties that ionic liquids offer in gas separations and energy storage.
VV3: Poster Session
Session Chairs
Rico E. Del Sesto
Yukihiro Yoshida
Tuesday PM, April 02, 2013
Marriott Marquis, Yerba Buena Level, Salons 7-8-9
9:00 AM - VV3.01
Electroposition in Ionic Liquid of SiGe Alloy Thin Films and Nanowires
Karine Namur 1 Jeremy Mallet 1 Florie Martineau 1 Michel Troyon 1 Michael Molinari 1
1University of Reims Champagne Ardenne Reims France
Show AbstractSiGe alloys (thin films and nanowires) have numerous applications in various domains (transistors, photovoltaic cells or even thermoelectrical devices). Interest of this material relies on its compatibility with existing silicon technology and particularly on its adjustable band gap with composition and dimensions.
CVD process is the commonly used technic to grow SiGe materials. While it can give well crystallized material, it remains a constraining process which needs high vacuum and high temperature and an accurate adjustment of growth parameters to control the composition of the alloy. Electrodeposition in Room Temperature Ionic Liquids is then an interesting alternative way of growing SiGe at a lower cost and under room-temperature conditions and atmospheric pressure and thus transposable more easily to future industrial large scale synthesis. However to be competitive, it is necessary to understand and control the chemical composition and growth kinetic of SiGe alloys electrodeposition, because both can have a drastic influence on the physical properties of the alloy.
Whereas reliable models describe well electrodeposition process of alloy in aqueous solvent, there is an important lack to describe mass transport and material growth in RTILs. One of the main differences between water and RTILs is the viscosity. One can note that as for water, the viscosity of RTILs is supposed to be strongly correlated to the ionic conductivity and ionic diffusion. In consequence this study sheds a light on the influence of several electrodeposition parameters such as potential (or current density), precursor&’s concentrations, temperature on the composition and the growth rate of the SiGe alloy for thin films and nanowires using two different RTILs.
By adjusting growth parameter, pure SiGe thin films and nanowires can be synthesized over a wide range of composition from (10 at% to 90 at% of Ge). Finally, the correlation between electrodeposition parameters and structural characterizations and the promising optical properties of the NWs will be discussed.
9:00 AM - VV3.02
Supramolecular Features of Materials Based on Zwitterionic Molecules: A Quantum Chemical Study
Ernesto Lopez-Chavez 1 Alberto Garcia-Quiroz 1 Gabriela Esmeralda Orozco-Duran 3 1 Luis Silvestre Zamudio-Rivera 2 Jose Manuel Martinez-Magadan 2 Eduardo Buenrostro-Gonzalez 2 Raul Hernandez-Altamirano 2
1Autonomous University of Mexico City Mamp;#233;xico, D.F. Mexico2Mexican Institute of Petroleum Mamp;#233;xico, D.F. Mexico3National Politechnic Institute Mamp;#233;xico, D.F. Mexico
Show AbstractIn this work we present a quantum chemical study pertaining to some supramolecular complexes acting as wettability modifiers of oil-water-limestone system. The complexes studied are derived from zwitterionic liquids of the types N'-alkyl-bis, N-alquenil, N-cycloalkyl, N-amyl-bis-beta amino acid or salts acting as sparkling agents. We studied two molecules of zwitterionic liquids (ZL10 and ZL13), the HOMO and LUMO levels, and the energy gap between them, were calculated, as well as Electron Affinity (EA) and Ionization Potential (IP), chemical potential, chemical hardness, and chemical electrophilicity index and selectivity descriptors such as Fukui indices.
9:00 AM - VV3.03
Glyme-Na Salt Complex as a New Solvate Ionic Liquid
Shoshi Terada 1 Risa Nozawa 1 Kazuki Yoshida 1 Kaoru Dokko 1 Masayoshi Watanabe 1 Kazuhide Ueno 1
1Yokohama National University Yokohama Japan
Show AbstractRoom temperature ionic liquids (RTILs) are desirable electrolyte materials for the batteries because of their unique properties such as non-volatility, nonflammability and high thermal and electrochemical stability. We have reported that glyme-Li salt complexes, comprising equimolar mixtures of a glyme (CH3O(CH2CH2O)nCH3) and a Li salt, have similar properties to RTILs and classified as solvate ionic liquids. Certain glyme-Li salt complexes such as lithium bis(trifluoromethylsulfonyl)amide (Li[TFSA]) and tetraglyme or triglyme are liquid at room temperature and show high thermal stability, high lithium ion transference number, and high lithium ion concentration. We demonstrated reversible charge-discharge of lithium secondary batteries using glyme-Li salt complex as an electrolyte.
The most widely used secondary batteries today as the power sources of electronic devices are lithium batteries. In addition, large scale lithium batteries are now being developed for electric vehicles (EV) and energy storage for electrical power generated by wind farm and solar energies. However, the lithium resources are limited and unevenly distributed to certain countries. The development of batteries without using lithium is desirable, and sodium is attracting much attention because of its abundance.
In this study, we prepared a glyme-Na salt complex by mixing pentaglyme and NaTFSA in a various molar ratio and investigated its thermal properties by DSC and TG. Equimolar pentaglyme-NaTFSA mixture was liquid at room temperature and melting point was found to be 31.7 °C, which is different from either that of pure glyme or NaTFSA. The thermogravimetric analysis of the equimolar pentaglyme-NaTFSA mixture showed weight loss at such temperature of neither pure glyme nor NaTFSA. These results suggest the equimolar mixture forms a complex and can be regarded as a sodium solvate ionic liquid. Physicochemical properties of equimolar pentaglyme-NaTFSA salt complex were measured at 30 °C. The conductivity was 0.6 mS cm-1, the viscosity was 244 mPa s, the sodium concentration was 2.44 mol dm-3, and the ionicity calculated by the Walden plot was as high as 0.64. In conclusion, the glyme-Na salt complexes have physicochemical properties similar to those of conventional ionic liquids. Possible application of the sodium solvate ionic liquid to sodium batteries will also be discussed.
9:00 AM - VV3.04
Pyrrolinium-based Ionic Liquids with Ether Substituents as Electrolytes for Lithium Ion Batteries
Hyung-Tae Kim 1 Hyeroung Lee 1 Oh min Kwon 1 Taeeun Yim 1 Junyoung Mun 1 Seung M. Oh 1 Geon Joong Kim 2 Young Gyu Kim 1
1Seoul National University Seoul Republic of Korea2Inha University Incheon Republic of Korea
Show AbstractLithium ion batteries (LIBs) have some advantages such as a high energy density, negligible memory effect and a less self-discharge. Consequently, they have been applied to not only small electronic devices but also large energy storage systems. Although LIBs have been considered to be promising rechargeable power sources for next-generation HEVs, the safety issue of LIBs must be overcome to realize large, high-power, and high-voltage LIBs. The highly flammable and volatile carbonate type solvents that are used in common liquid electrolytes can be major causes of fire and explosion. Thus, ionic liquids (ILs) have attracted much attention due to their superior thermal stability. ILs are salts that remain as liquid at room temperature even if they are composed of ionic species, cations and anions. Due to the ionic nature in bonding, ILs show favorable physicochemical properties such as high ionic conductivity, non-volatility, and non-flammability as well as a wide liquid range and wide electrochemical stability window. Previously reported imidazolium-based ILs with low viscosity and high ionic conductivity have some defects as electrolytes for LIBs. To deal with decomposition of acidic proton at the C-2 position of the imidazolium ring, we have studied saturated cyclic ammonium-based ILs based on pyrrolidine or piperidine, which showed more stable electrochemical behavior compared to the imidazolium-based ILs but less favored properties such as high viscosity and lower ionic conductivity.
In the present work, novel pyrrolinium-based ILs were studied as electrolytes for LIBs to overcome those problems. Introduction of ether substituents into the pyrrolinium ring was expected to give some positive effect on not only electrochemical stability but also physicochemical properties. Several pyrrolinium-based ILs with ether substituents that were synthesized in the present study showed higher thermal stability as expected than the conventional carbonate electrolytes. In addition, these pyrrolinium-based ILs showed a good cycle performance at high temperature as well as at room temperature.
9:00 AM - VV3.05
Polymeric Ionic Liquids with Enhanced Electrical Conductivity and Tuneable Mechanical Properties
Kaija Pohako-Esko 1 2 3 Martin Timusk 2 3 Silver Leinberg 2 3 Kristjan Saal 2 3 Ruenno Lohmus 2 3 Ilmar Kink 2 3 Uno Maeorg 1
1University of Tartu Tartu Estonia2University of Tartu Tartu Estonia3Estonian Nanotechnology Compentence Center Tartu Estonia
Show AbstractIonic liquids (IL) are defined as room temperature molten salts. They are in focus of intense research because of their extraordinary chemical and physical properties [1].
Recently interest in polymeric forms of ILs (PILs) has been increasing. Typical characteristics of ILs combined with mechanical durability of polymers make PILs applicable as solid electrolytes in electrochemical devices, like batteries and fuel cells [2-4]. Another major area of PIL research is the use of the material as gas absorber [5]. The extraordinary solvation properties inherent to ILs make PILs attractive for preparation of composite materials such as “bucky plastic” [6] or PIL-cellulose composites [7].
In this study new type of PILs with enhanced conductivity and tuneable mechanical properties were prepared by adding ionic liquid [EMIM][BF4] to methacrylate type PILs.
For synthesis of PIL monomers, 1-[(n-methacryloyloxy)alkyl]-3-methylimidazolium salts with different alkyl chain length, a new method was developed with the main focus to avoid premature polymerization during synthesis, which is a main drawback of conventional synthesis routes [8].
Synthesised PIL monomers were mixed with [EMIM][BF4] in different ratios. Polymerization of the obtained mixtures was carried out using UV radiation. During the polymerization electrical conductivity of the material was measured, which was proven as a convenient method for observing the progression of the polymerization reaction.
It was shown that content of [EMIM][BF4] has a significant influence on the properties of PIL. PILs prepared solely from PILs monomers were hard and brittle, but the addition of [EMIM][BF4] made PILs more elastic. The addition of IL also had a remarkable effect on the conductivity of PILs, which varied from 10-3 to 10-5 S cm-1 at room temperature and showed higher values with increasing [EMIM][BF4] content.
References:
[1] Wasserscheid; P., Welton; T. Ionic Liquids in Synthesis. Wiley-VCH Verlag GmbH & Co., 2002.
[2] Green, O.; Grubjesic, S.; Lee, S.; Firestone, M. A. Polym. Rev. 2009, 49, 4, 339 - 360.
[3] Green, M. D.; Long, T. E. Polym. Rev. 2009, 49, 291 - 314.
[4] Armand, M.; Endres, F.; MacFarlane, D. R.; Ohno, H.; Scrosati, B. Nat. Mater. 2009, 8, 621-929.
[5] Tang, J.; Tang, H.; Sun, W.; Plancher, H.; Radosz, M.; Shen, Y. Chem. Commun. 2005, 3325-3327.
[6] Fukushima, T.; Kosaka, A.; Yamamoto, Y.; Aimiya, T.; Notazawa, S.; Takigawa, T.; Inabe, T.; Aida, T. Small 2006, 2, 554 - 560.
[7] Murakami, M.; Kaneko, Y.; Kadokawa, J. Carbohydr. Polym. 2007, 69, 378-381.
[8] Ding, S.; Tang, H.; Radosz, M.; Shen, Y. J. Polym. Sci., Part A: Polym. Chem. 2004, 42, 5794-5801.
9:00 AM - VV3.06
Lithium Solvate Ionic Liquids for Polymer Electrolytes
Ryosuke Kido 1 Kaori Iwata 1 Satoru Imaizumi 1 Kazuhide Ueno 1 Kaoru Dokko 1 Masayoshi Watanabe 1
1Yokohama National University Yokohama Japan
Show AbstractIonic liquids have been studied as Li+-conducting electrolytes by dissolving Li-salts in conventional ILs. However, low ionic conductivity and low lithium transference numbers remain certain issues to be addressed. In previous work, we found that equimolar mixtures of glymes (triglyme (G3) and tetra glyme (G4)) and lithium bis(trifluoromethanesulfonyl)amide (LiTFSA), in which the robust complex cation [Li(glyme)]+ was formed, behaved like typical ILs: the glyme-Li salt complexes were liquid at ambient temperatures and showed high ionic conductivity, high lithium transference number, good thermal stability, and low volatility. Thus, they can be recognized as lithium solvate ILs and would be a promising electrolyte alternative to conventional ILs containing Li-salts.
Due to the remarkable properties of the lithium solvate ILs, polymer electrolytes (ion gels) of the lithium solvate ILs would also be an alternative to well-studied polymer electrolytes, such as poly(ethylene oxide) and LiTFSA binary systems. Similar to the concept of ion gels and “polymer-in-salt electrolytes”, the solvate ILs serve as both lithium-ion conducting species and plasticizers toward matrix polymers, and thus resulting ion gels become rubbery electrolytes showing high conductivity.
In this work, we studied polymer electrolytes of a lithium solvate ionic liquid and three different polymer matrices, poly(ethylene oxide)(PEO), poly(methyl methacrylate)(PMMA) and poly(butyl acrylate)(PBA). PBA-[Li(G4)1][TFSA] mixtures (unit molar ratio = 1 : 1) exhibited high conductivity of ca. 0.6 mS/cm at room temperature. The lithium transference numbers in the polymer electrolytes, measured by pulsed-field gradient spin-echo NMR (PGSE-NMR) method, were found to be ca. 0.5. This is much higher than the reported value for classical PEO-LiTFSA system, and was independent of the polymer concentrations in non-coordinating polymer matrices, such as PMMA-[Li(G4)1][TFSA] mixtures and PBA-[Li(G4)1][TFSA] mixtures. On the contrary, the lithium transference numbers in PEO-[Li(G4)1][TFSA] mixtures decreased with increasing the amount of PEO, since Li+ was trapped by the interaction with PEO main chains. The Li+ coordination in the polymer electrolyte was further analyzed by Raman spectroscopy. In addition, we will present effect of polymer structure on the thermal and other electrochemical properties of the polymer electrolytes.
9:00 AM - VV3.07
High Performance Ionic Liquid Based Electrolytes for Energy Applications
Frank M Stiemke 1 Thomas J.S. Schubert 2 Maria Ahrens 2
1IOLITEC Inc. Tuscaloosa USA2IOLITEC GmbH Heilbronn Germany
Show AbstractThe fast and efficient storage of electric energy delivered by renewable sources is one of the major challenges nowadays. Besides batteries (e.g. Li-Ion Batteries) supercapacitors are strongly in the focus of research by industry and scientific institutions. New is the combination of both types (long term and short term storage) in one device. Novel types of electrolytes are currently under investigation worldwide. For short term storage of energy electric double-layer capacitors (EDLCs, “supercaps”, “goldcaps” or “ultracaps”) are the most common technique. The performance of the EDLC is determined by the specific power density, the specific energy density and the charging time of the device. Today&’s supercaps suffer from limited specific energy density. Important requirements for the EDLC electrolytes include large electrochemical stabilities, sufficient to good conductivities and viscosities as well as incombustible electrolyte materials for safety reasons.
Ionic liquids (ILs) - salts which are liquid at temperatures below 100°C - show interesting profiles of physical and chemical properties which allows their use as safe electrolytes in batteries and EDLCs. These properties include tunable viscosities and conductivities, chemical and thermal stability as well as large electrochemical windows, and incombustibility at temperatures below their decomposition point.
In this presentation we will give an overview about recent developments in the field of LIBs and EDLCs using IL-based electrolytes. The focus of this talk will be on the use of mixtures of ionic liquids and additives in order to increase the performance of such electronic devices. In the field battery applications, we&’ll put also some light on their ability to dissolve Lithium-salts. For EDLC applications we&’ll focus on techniques to lower the viscosity of ILs, resulting in faster charging/discharging speeds.
9:00 AM - VV3.08
Development of High-current Ionic Liquid Ion Source toward Surface Modification
Mitsuaki Takeuchi 1 Takuya Hamaguchi 1 Hiromichi Ryuto 1 Gikan H Takaoka 1
1Kyoto University Kyoto Japan
Show AbstractPolyatomic ion beam characterized by equivalently high current with low energy is an important technology not only for ultra-shallow ion-implantation, but also for surface modifications, e.g. oxidizing, redoxizing, coating, sputtering, roughening, and smoothing. These are induced by physical and/or chemical interactions among surfaces and many kinds of functional groups included in the incident polyatomic ions.
One of the most interested polyatomic ion is room temperature molten salts: ionic liquids(ILs). In the recent decade, ionic liquid ion source (ILIS) has been reported by several groups toward applications to electronic space propulsion, focused ion beam processing, probing ions in secondary ion mass spectroscopy. Ion order to improve the IL beam stability, we has developed a field-type ILIS made of carbon tip embedded with carbon felt, because the carbon has a good wettability of ILs at room temperature without any surface treatment[1]. Using the ILIS, we obtained many types of IL ion beam: positive ion beam with pure cations, negative ion beam with pure anions, and positive/negative cluster ion beams containing cation-anion pairs[2]. This leads to possibility for charge-up-less modification of insulating substrates such as a glass, which has been widely used electronic and optical devices as seen in touch screens. Toward practical applications, a high-current ion beam which can make substrates modify more rapidly and extensively is required. In this study, development of a high-current ILIS was investigated with respect to multi-emitter.
The developed ILIS consists of an ionic liquid reserver, a feeding tube, a multiple carbon tips emitter embedded with carbon felt and a extractor with a through hole. Ion beam properties were evaluated in case of 1-butyl-3methylimidazolium hexafluorophosphate(BMIM-PF6) and 1-ethyl-3methylimidazolium tetrafluoroborate(EMIM-BF4) under vacuum below 1e-5 torr. As a result, it was found that current of the ionic liquid ion beam extracted from the emitter increased with increasing number of carbon tip.
References
[1]M. Takeuchi, H. Ryuto, G.H. Takaoka, AIP Conference Proceedings 1321 (2011) 456.
[2]M. Takeuchi, T. Hamaguchi, R. Ueda, H. Ryuto, G.H. Takaoka, in:, IUMRS-International Conference on Electronic Materials IUMRS-ICEM at Pacifico Yokohama, Yokohama, Japan, (2012).
VV1
Session Chairs
Rico E. Del Sesto
Charles Hussey
Tuesday AM, April 02, 2013
Marriott Marquis, Golden Gate Level, Salon C2
9:30 AM - *VV1.01
Electrochemistry and Spectroscopy of f-Electron Elements in Room-temperature Ionic Liquids
Charles L. Hussey 1 Li-Hsien Chou 1 Yunfeng Pan 1
1University of Mississippi University USA
Show AbstractPyrochemical methods for the reprocessing of spent nuclear fuel (SNF), such as those based on halide volatility and direct electrodeposition, serve as attractive alternatives to established hydrometallurgical processing methods. However, current pyrochemical technology is based on high melting inorganic salts such LiCl-KCl. Hydrophobic, moisture stable room-temperature molten salts or ionic liquids are under evaluation as potential substitutes for these molten inorganic salts in some applications. Unfortunately, very little is known about the chemistry/electrochemistry of f-electron elements (actinides and lanthanides) in these ionic liquids. In this paper, we will discuss the electrochemical and spectroscopic behavior of a number of such elements, including cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), and ytterbium (Yb) in ionic liquids based on the combination of quaternary ammonium cations with bis(trifluoromethylsulfonyl)imide anions. These studies were also carried out in ionic liquid solutions containing complexing agents such as chloride and the neutral tridentate ligand, N,N,N&’,N&’-tetra(n-octyl)diglycolamide (TODGA). (TODGA is an extractant with potential applications for the recovery of f-electron elements during the reprocessing of spent nuclear fuel.) The overall aim of this investigation is to probe the solvation, accessibility, and stability of the various oxidation states of f-electron species in these ionic liquids. This work was funded by the Division of Chemical Sciences, Geoscience, and Biosciences, Office of Basic Energy Sciences of the U. S. Department of Energy through Grant DE-AC02-98CH10886.
10:00 AM - VV1.02
Nanoparticle Electrides
Scott C Warren 1 Yong Yan 1 Bartosz Grzybowski 1
1Northwestern University Evanston USA
Show AbstractNanoparticles with self-assembled monolayers (SAMs) have emerged as important platforms for sensing, diagnostics and energy conversion. In solid films comprised of these particles, the SAM often acts as an insulator, restricting charge transport to a tunneling current between adjacent nanoparticle cores. Here we show that for nanoparticles in which the SAM comprises an ionic liquid, electrons can be injected into the SAM, transforming it into an electron conductor. The electrons do not reside on atomic or molecular orbitals but are instead solvated by cationic sites that are part of the SAM. Our analysis is supported by a direct measurement of the magnetic properties imparted by the injection of unpaired electrons into the SAM as well as an excellent correspondence between the electrical properties of the materials and a theoretical model that we have developed. These mesoscopically ordered films of nanoparticles have electrons acting as anions and, as such, can be considered an electride. Although solvated electrons had been identified in only a small number of systems—e.g., those formed by combining an alkali metal with liquid ammonia, crown ethers, or cryptands—the observation of solvated electrons in nanoparticle-based materials may have important implications for this technologically important class of materials. Most especially, the formation of nanoparticle electrides provides a mode for efficient electron transport within the SAM, thereby enabling applications in energy conversion and information processing. In particular, we demonstrate the construction of a transistor and a thermistor based on these nanoparticle electrides.
10:15 AM - VV1.03
CO2 Reactive Ionic Liquids Prepared from Novel Substituted 1,2,3-Triazoles
Robert L. Thompson 1 Hunaid Nulwala 3 Erik Albenze 1 Damodaran Krishnan 2 David Luebke 3
1URS/National Energy Technology Laboratory Pittsburgh USA2University of Pittsburgh Pittsburgh USA3U.S. Dept. of Energy/National Energy Technology Laboratory Pittsburgh USA
Show AbstractNew materials are required for effective capture of CO2 to address the issues faced by raising CO2 concentrations in the atmosphere. Ionic liquids (ILs) are promising candidates to selectively remove CO2 from mixed gas streams due to their desirable properties. These properties include high thermal stability, high CO2 solubility, low vapor pressure, large electrochemical window, and generally environmentally benign nature.
The use of aprotic heterocyclic anions (AHAs) in ionic liquids has been shown to be a successful general approach to selectively and reversibly react with CO2 without suffering detrimental increases in viscosity. Here we will present the preparation and detailed of characterization of 1,2,3-triazoles with a base-labile pivalate group at the 1-position utilizing click chemistry. From the synthesized triazoles, a library of five task specific 1,2,3-triazolide AHA ionic liquids based on a phosphonium core was synthesized and fully characterized. It was observed that the side groups at the 4-position has influence on the CO2 solubility, and certain conclusions can be drawn regarding the solubility of CO2 in these materials. The viscosities and surface tensions of these ILs were also measured. NMR and FTIR studies reveal interesting insight suggesting that neat IL samples when reacted with CO2 form multiple isomers of carbamate product. Additionally, computational insights were gained and compared to experimental studies which will also be discussed. This work provides important insights to AHA ILs and designing better materials.
10:30 AM - *VV1.04
Novel Collection, Storage, and Analysis of CBRNE Forensic Samples Using Ionic Liquids
John S. Wilkes 1 Cynthia Corley 1 Jessica Drewicz 1 Michelle Kiyota 1 Joseph A. Levisky 1 Hannah A. Miller 1 Michael Wilcox 1
1US Air Force Academy USAF Academy USA
Show AbstractForensic specimen collection of Chemical, Biological, Radiological, Nuclear, and Explosive (CBRNE) compounds during a forensic investigation continues to challenge military investigators as well as civilian first responders. The ideal medium for this requirement will extract the compounds of interest in high yield, retain the compounds in a chemically and physically stable form, and be compatible with qualitative and quantitative analyses. Ionic liquids were selected for this study due to extremely low volatility, high chemical and thermal stability, and “green chemistry” compatibility. In this study the radiological and nuclear parts of the CBRNE spectrum were not included, but some common drugs (licit and illicit) were added to the list. The example chosen for a chemical warfare agent was 2-chloroethylphenyl sulfide, which is a generally accepted simulant for the sulfur mustard agent bis-2-chloroethyl sulfide. Bacillus thuringiensus and B. thuringiensus and B. cereus were studied as surrogates for the biological agent B. anthracis (the anthrax organism). TNT (2,4,6-trinitrotoluene) was used as a common explosive for this project. The licit drugs tested included local anesthetics, dissociative anesthetics, including midazolam and flunitrazepam, frequently used as “date rape” drugs and morphine, a potent narcotic analgesic. The illicit drugs, included cocaine, which could also be considered as a licit drug under certain circumstances, and tetrahydrocannibinol (THC).
The ionic liquids used in this study included 1-butyl-3-methylpyrrolidinium bis(trifluoromethanesulfonyl)amide (BMPyr-Tf2N), 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIm-BF4), trihexyltetradecylphosphonium chloride (PR4-Cl). Other ionic liquids were used for specific purposes and are described in the text of this document. 1-Ethyl-3-methylimidazolium tetrafluoroborate produced a novel colorimetric product when solubilizing TNT and was also effective in collecting numerous compounds from hard surfaces.
The analyses of the chemical, explosive and drug compounds collected by ionic liquid impregnated swags was usually accomplished by separation by liquid chromatography, and detection by UV absorption and electrospray ionization time-of-flight mass spectrometry (LC/UV-ESI-TOF-MS). The presence of bacteria or their viable spores was done by standard culture methods.
11:30 AM - *VV1.05
Structure-property Relations in Ionic Liquid Crystals
Anja V Mudring 1 Kathrin Stappert 1 Mei Yang 1
1Ruhr-Universitamp;#228;t Bochum Bochum Germany
Show AbstractIonic liquid crystals (ILC) combine the properties of ionic liquids (IL) and liquid crystals (LC). Apart from typical IL features like a low vapor pressure many of the physicochemical and mechanical properties of ILCs highly depend on the direction such as the ionic conductivity which is due to the LC character. Because of this interesting property combination ILCs are of interest for applications in fields ranging from electrochemistry to transition metal catalysis. In recent years a number of cation types for ionic liquids have been developed, but still the most commonly used ones are imidazolium cations. Hence, most of the ionic liquid crystals studied so far are based on imidazolium cations as well. For example mesomorphic behavior has been reported for 1-alkyl-3-methylimidazolium salts with long alkyl chains.
But what happens to the mesophase if we abstain from the acidic proton and replace the imidazolium by 1,2,3-triazolium? To answer this question several triazolium based ILs have been synthesized and their structural and thermal behavior characterized. This analysis shows that all of the investigated materials are indeed thermotropic liquid crystals. Identity and structure of the mesophases will be discussed in detail and the differences between 1,3-dialkyltriazolium and 1,3-dialkylimidazolium will be considered which allows to reveal important structure-property relationships.
12:00 PM - VV1.06
Acid Catalyzed Hydrolysis of Biomass in Ionic Liquid and Separation of Sugars Using Liquid-liquid Extraction
Ning Sun 1 Noppadon Sathitsuksanoh 1 Kim Tran 1 2 Vitalie Stavila 2 Anthe George 1 3 Kenneth L Sale 1 2 Seema Singh 1 2 Blake A Simmons 1 2 Bradley M Holmes 1 2
1Joint Bioenergy Institute Emeryville USA2Sandia National Laboratories Livermore USA3Sandia National Laboratories Livermore USA
Show AbstractThe use of Ionic liquids (ILs) as biomass solvents is considered to be an attractive alternative for the pretreatment of lignocellulosic biomass. It has been shown that pretreatment with imidazolium based ILs, containing specific anions can greatly accelerate the enzymatic digestion of the pretreated biomass. Acid catalysis have also been used to produce sugars and other high value compounds in situ through the acid catalyzed hydrolysis of biomass dissolved in imidazolium chloride ILs. Acid catalysts have been used previously to hydrolyze polysaccharides into sugars during IL pretreatment. This could potentially provide a means of liberating fermentable sugars from biomass without the use of costly enzymes. However, the separation of the sugars from the aqueous IL and recovery of IL is challenging and imperative to make this process viable.
In this work, we use a kosmotropic salt solution to induce the formation of a biphasic system from a concentrated solution of sugars produced by the acid catalyzed hydrolysis of switchgrass in the IL 1-butyl-3-methylimidazolium chloride. The biphasic system allows for the easy recycling of IL and recovery of the sugars. This process provides an alternative route to the production of monomeric sugars from biomass that eliminates the need of enzymes, and reduces the amount of water required by the process.
12:15 PM - VV1.07
Electrowetting-on-Dielectric Behavior of Ionic Liquids: Fluidic versus Electrical Hysteresis Effects
Natalie Gogotsi 1 Marriner Merrill 1 James P. Thomas 1
1Naval Research Laboratory Washington USA
Show AbstractPhysical manipulation of small quantities of ionic liquids (IL&’s) on surfaces and in capillary networks is an important capability for effective IL use in microfluidics, lab-on-a-chip, and drop-based synthesis applications. An elegant and useful technique for moving fluids in contact with a solid surface and controlling their meniscus shape is electrowetting-on-dielectric (EWOD). This technique permits control of the contact angle at a fluid-air-solid interface (triple line) using an applied potential between a conductive fluid and an electroded solid surface that is insulated and made non-wetting with thin dielectric and hydrophobic layers. Electrostatic stresses in the fluid create a lateral “spreading” force on the triple line, which causes the contact angle to change from non-wetting to wetting with fluid surface distortion and movement. Interestingly, several prior studies of EWOD with IL&’s have shown inconsistent results and disagreement with theory relative to that observed with aqueous solutions.
In an attempt to better understand and explain these disparities, we have conducted a detailed study of contact angle as a function of applied potential (0 to +/- 200 V) for two methyl-imidazolium based IL&’s on three different substrates with surface roughness values ranging from 10&’s to 100&’s of nanometers. We discovered that EWOD experiments performed using constant sessile drop volumes with changing applied potentials, which is common practice, lead to the observed disparities. This effect is more significant with liquids having higher viscosities and non-ideal surfaces with greater triple line pinning (e.g. IL&’s on a rough surface). More consistent data can be obtained with experiments that utilize constant applied potential while varying the droplet volume to obtain ‘fluidic-based&’ advancing/receding contact angles. Using this method, we show that IL&’s do follow the theoretical EWOD predictions described by the Young-Lippmann equation. Details of the experiments and analysis used to address these issues will be discussed along with a brief description of an application being developed that uses EWOD control of IL&’s in poro-vascular (solid) laminate skins to achieve multifunctional structure-plus-surface morphology control.
12:30 PM - *VV1.08
Selective Gas Absorption by Ionic Liquids and by Supported Ionic Liquid-phase (SILP) Absorbers - Mechanistic Aspects
Rasmus Fehrmann 1 Andreas J. Kunov-Kruse 1 Peter Thomassen 1 Susanne L. Mossin 1 Helene Kolding 1 Anders Riisager 1 Saravanamurugan Shunmugavel 1 Jacques Rogez 2
1Technical University of Denmark Kgs.-Lyngby Denmark2Universitamp;#233; de Provence Marseille France
Show AbstractEmission of acidic gases such as NOx and SOx and COx from e.g. energy production by fossil fuels in power plants and from ships, is a major concern in relation to atmospheric pollution and climate changes. Therefore, these gases have to be effectively removed from flue gases. Presently - if carried out at all- this is mainly achieved by relatively energy intensive and resource demanding technologies via e.g. selective catalytic reduction (SCR) of NOX with ammonia, by gypsum formation after SO2 wet-scrubbing while organic amines are being used as absorbents in CO2 scrubbers. This leads to concern about, e.g. intensive energy requirements for desorption, corrosion of steel pipes and pumps, CO2 absorption capacity and thermal decomposition of the amine. In this work, we present our latest results regarding specific ionic liquids (IL) tuned by design to perform as selective, high-capacity absorbents of the environmentally problematic flue gases SO2 , NO ,NO2 and CO2 .
Reversible absorption has been obtained for several different ILs at different temperatures and flue gas compositions. Furthermore, different porous, high surface area carriers have been applied as supports for the ionic liquids to obtain Supported Ionic Liquid-Phase (SILP) absorber materials.
The results show that CO2 , NO, NO2 and SO2 can be reversible and selective absorbed using different ILs and that SILP absorbers are promising materials for industrial flue gas cleaning. Absorption / desorption dynamics can be tuned by temperature, pressure ,gas concentrations and the properties of the porous carrier.
The mechanistic details regarding gas absorption and desorption based on our latest theoretical and experimental investigations will be highlighted.
Symposium Organizers
Rico E. Del Sesto, Los Alamos National Laboratory
Sheng Dai, Oak Ridge National Laboratory
Robin D. Rogers, The University of Alabama
Yukihiro Yoshida, Meijo University
VV5
Session Chairs
Rika Hagiwara
Jenny Pringle
Wednesday PM, April 03, 2013
Marriott Marquis, Golden Gate Level, Salon C2
2:30 AM - *VV5.01
Functional Ion Gels: Block Polymer/Ionic Liquid Composites for Advanced Applications
Timothy Lodge 1 2 Dan Frisbie 2 Sipei Zhang 2 Keun-Hyung Lee 2 Yuanyan Gu 1
1University of Minnesota Minneapolis USA2University of Minnesota Minneapolis USA
Show AbstractIonic liquids possess many attributes that render them attractive candidates for diverse applications. Block polymer self-assembly in ionic liquids can impart the desired nanostructure and mechanical integrity for a particular function, without compromising the performance of the ionic liquid. We illustrate these general principles in two specific cases using ABA triblocks with ionic-liquid compatible midblocks. First, the extremely high specific capacitance combined with rapid ion motion makes ions gels superior gate dielectrics in organic thin film transistors. The possibility of printed plastic circuitry with MHz switching will also be demonstrated. Second the remarkable thermodynamic selectivity of certain ionic liquids for CO2 over N2 or CH4 offers a route to rapid membrane separations, if the ionic liquid can be suitably immobilized. An ABA system in which the midblock is itself a polymerized imidazolium salt serves this purpose, and performance above the famous “Robeson&’s Upper Bound” has been achieved.
3:00 AM - VV5.02
Ionic Liquids Behave as Dissociable Liquids
Matthew Allen Gebbie 1 Markus Valtiner 2 Banquy Xavier 3 Eric Fox 4 Wesley A Henderson 4 Jacob N Israelachvili 3 1
1University of California, Santa Barbara Santa Barbara USA2Max-Planck-Institut fur Eisenforschung GmbH Damp;#252;sseldorf Germany3University of California, Santa Barbara Santa Barbara USA4North Carolina State University Raleigh USA
Show AbstractThe electrochemical properties of ionic liquids (ILs) are a critical determinant for the performance of IL-based electrochemical devices. Using a surface forces apparatus with in-situ electrochemical control of a gold surface, we quantitatively investigated equilibrium force-distance profiles of two dissimilar surfaces interacting across an IL. Force-distance profiles exhibit a long-range regime (surface separations out to 35 nm) that is solely attributable to electrostatic forces and is well-fitted by equations describing overlapping diffuse electric double-layers. Short-range forces, arising from an interplay of van der Waals, structural (steric) and oscillatory forces, dominate below 3 nm surface separations. These results indicate that the IL ions behave as if they exist in two distinct effective states: associated (electrically neutral) ions, and freely dissociated ions. The equilibrium for this effective dissociation reaction (pKd = 9.14) is quantitatively explicable in terms of the energetics of thermally dissociating ions in a dielectric medium.
3:15 AM - VV5.03
Development of Organic Ionic Plastic Crystals as Solid State Electrolytes for Energy Generation and Storage Applications
Liyu Jin 1 Katherine Nairn 1 Patrick Howlett 3 Douglas MacFarlane 2 Maria Forsyth 3 Jenny Pringle 1 2
1Monash University Clayton Australia2Monash University Clayton Australia3Deakin University Burwood Australia
Show AbstractThe advantages of ionic liquids as electrolytes for electrochemical applications such as lithium batteries and dye-sensitized solar cells are well recognized. Organic Ionic Plastic Crystals (OIPCs) are crystalline phases found in many of the same organic salt families as ionic liquids but these materials have elevated melting points and exhibit various forms of disorder, which is the origin of their plastic mechanical properties. These plastic crystal materials are showing increasing promise as solid state electrolytes for various electrochemical applications.
OIPCs display one or more solid-solid phase transitions before melting, which are associated with the onset of rotational or translational motions of the ions and thus a progressive transformation from an ordered crystalline phase to an increasingly disordered structure. This disorder is paramount to the fast ion conduction of dopant species, such as lithium ions or iodide/triiodide, which is core to the efficient performance of the OIPCs as solid state electrolytes. Analysis of the rotational or translational ionic motions within OIPCs is non-trivial and demands a range of in-depth techniques, ideally in combination with computational studies.
Here we discuss our recent research into the development of OIPC electrolytes for lithium batteries[1] and dye-sensitised solar cells.[2] Furthermore, we discuss a model of the ion transport in a new phosphonium-based OIPC in the different solid phases,[3] proposed using data from variable temperature solid state NMR analysis and second moment calculations.
References
[1]. J. Sunarso, Y. Shekibi, J. Efthimiadis, L. Jin, J. M. Pringle, A. F. Hollenkamp, D. R. MacFarlane, M. Forsyth and P. C. Howlett, J. Solid State Electrochem., 2012, 16, 1841-1848.
[2]. V. Armel, M. Forsyth, D. R. MacFarlane and J. M. Pringle, Energy & Environmental Science, 2011, 4, 2234-2239.
[3]. L. Jin, K. M. Nairn, C. M. Forsyth, A. J. Seeber, D. R. MacFarlane, P. C. Howlett, M. Forsyth and J. M. Pringle, Journal of the American Chemical Society, 2012, 134, 9688-9697.
3:30 AM - *VV5.04
Materialization of Ionic Liquids: Polymer Electrolytes of Ionic Liquids
Masayoshi Watanabe 1
1Yokohama National University Yokohama Japan
Show AbstractIonic liquids (ILs) are liquids comprising entirely ions, which afford them non-volatility, non-flammability, and high ionic conductivity. Certain ILs can be compatible with polymers [1]; in such cases polymer electrolytes containing ILs (ion gels) can be formed [2-4]. Generally, cations and anions of ionic liquids have very low Lewis acidities and Lewis basicities, respectively, and they are self-dissociative without the aid of solvation of molecular and polymer solvents [5-6]. Thus, the interaction of ions of ILs and polymers in the polymer electrolytes are very weak, which clearly contrasts with conventional polyether electrolytes containing lithium salts. This weak interaction makes possible decoupled ionic motion from the segmental motion of polymers [7] and high ionic conductivity close to that of electrolyte solutions, while non-volatility and thermal stability is maintained thanks to the nature of ILs.
The ion gels can find a wide range of applications by designing properties of ILs. For instance, ion gels that exhibit high ionic conductivities (> 10-3 S cm-1) with wide electrochemical windows can be used as an electrolyte of an ionic polymer actuator [8-9], which has a tri-laminar structure consisting of the ion-gel electrolyte sandwiched between two composite carbon electrodes containing high-surface-area activated carbon powders (solid electric double layer capacitor (EDLC) structure). By applying relatively low voltages (< 3.0 V) to the electrodes, the actuator exhibits a soft bending motion. Taking the ionic transport mechanisms into consideration, a deformation model for actuators having solid EDLC structures is proposed [9]. The model points out the important factor, t+v+ minus; tminus;vminus; (t: cationic or anionic transference number; v: cationic or anionic volume), which determines the direction of deformation against applied voltage. A pplication of the ion gels to fuel cells will also be presented [10-12].
References
[1] Bull. Chem. Soc. Jpn. (Accounts) 85 (2012) 33. [2] JCS Chem. Commun. (1993) 929. [3] Electrochim. Acta 45 [12] Chem. Commun. (2007) 2539. [13] J. Am. Chem. Soc. 132 (2010) 9764. (2000) 1265. [4] J. Am. Chem. Soc. 127 (2005) 4976. [5] J. Phys. Chem. B 110 (2006) 19593. [6] Phys. Chem. Chem. Phys. 12 (2010) 1649. [7] J. Phys. Chem. B 109 (2005) 3886. [8] Macromolecules 45 (2012) 401. [9] J. Phys. Chem. B 116 (2012) 5080. [10] J. Phys. Chem. B 107, (2003) 4024. [11] Chem. Commun. (2007) 2539. [12] J. Am. Chem. Soc. 132 (2010) 9764.
4:30 AM - *VV5.05
Intermediate Phases of Ionic Solids and Liquids: Plastic- and Liquid Crystals of Fluorohydrogenate Salts
Rika Hagiwara 1 Kazuhiko Matsumoto 1 Ryosuke Taniki 1 Fei Xu 1 Takeshi Enomoto 1
1Kyoto University Kyoto Japan
Show AbstractNew ionic plastic crystals, N,N-dimethylpyrrolidinium fluorohydrogenate (DMPyr(FH)2F) and N-ethyl-N-methylpyrrolidinium fluorohydrogenate (EMPyr(FH)2F), exhibit a small entropy change of melting, 4.1 and 2.0 J K-1 mol-1, respectively, and have ionic plastic crystal phases in the temperature range of 258-325 and 236-303 K, respectively, although EMPyr(FH)2F has a remaining ionic liquid (IL) phase below 303 K. These phases have a NaCl-type structure, of which the lattice constants are 9.90 Å for DMPyr(FH)2F and 10.18 Å for EMPyr(FH)2F. Ionic conductivities of the ionic plastic crystal phases range from 100 to 101 mS cm-1 (e.g. 10.3 mS cm-1 at 298 K for DMPyr(FH)2F and 14.4 mS cm-1 at 288 K for EMPyr(FH)2F). Only the anion can move in the ionic plastic crystal phase as a charge carrier with a diffusion coefficient of ~10-7 cm2 s-1 and self-diffusion coefficient of the cation in the ionic plastic crystal phase was too low to measure.
Fluorohydrogenate salts of quaternary phosphonium cations with short alkyl and methoxy groups (tetraethylphosphonium (P2222+), triethyl-n-pentylphosphonium (P2225+), triethyl-n-octylphosphonium (P2228+), and triethylmethoxymethylphosphonium (P222(1O1)+)) have been synthesized by the metatheses of anhydrous hydrogen fluoride and the corresponding phosphonium bromide or chloride precursors. The three salts with asymmetric cations, P222m(FH)2.1F (m = 5, 8, and 1O1), are obtained as room temperature ILs. These phosphonium fluorohydrogenate ILs have wide electrochemical windows (> 4.9 V) with the lowest viscosity and highest conductivity in the known phosphonium-based ILs. Thermogravimetry shows their thermal stabilities are also improved compared to previously reported alkylammonium cation-based fluorohydrogenate salts. Tetraethylphosphonium fluorohydrogenate salt, P2222(FH)2F, exhibits two plastic crystal phases. The high temperature phase has a hexagonal lattice, which is the first example of a plastic crystal phase with an inverse nickel arsenide-type structure, and the low-temperature phase has an orthorhombic lattice. The high-temperature plastic crystal phase exhibits an ionic conductivity of 5 mS cmminus;1 at 323 K, which is the highest value for the neat plastic crystals.
Liquid crystalline mesophases with a smectic A interdigitated bilayer structure are observed for N-alkyl-N-methylpyrrolidinium fluorohydrogenate salts, CxMPyr(FH)2F (x = 14, 16, and 18), showing a fan-like or focal conic texture by the polarized optical microscope. Temperature range of the mesophase increases with increase in alkyl chain length (from 299.8 K for C14MPyr(FH)2F to 363.8 K for C18MPyr(FH)2F). The layer spacing in the smectic structure monotonously increases with increasing alkyl chain length and decreases with increasing temperature. The liquid crystalline mesophase of C14MPyr(FH)2F exhibits anisotropy in ionic conductivity and the ionic conductivity parallel to the smectic layer is roughly ten times larger than that perpendicular to it.
5:00 AM - VV5.06
Computational Study of Ionic Liquids Confined inside Amorphous Carbon Structures
Joshua Monk 1 3 Ramesh Singh 2 3 Francisco R Hung 3
1NASA ARC Moffett Field USA2University of Notre Dame Notre Dame USA3Louisiana State University Baton Rouge USA
Show AbstractIonic liquids (ILs) have potential applications as alternative electrolytes in devices such as electrochemical double layer capacitors and dye-sensitized solar cells. In these devices, the electrodes typically consist of a nanoporous material which is in contact with the IL. However, a fundamental understanding of the behavior of ILs inside nm-sized pores is still lacking. Such knowledge is essential to optimize the performance of these IL-based devices.
In this study we investigate the behavior of 1,3-dimethylimidazolium chloride, [dmim][Cl], confined inside three carbon systems, which consist of a single amorphous carbon nanotube (ACNT), hexagonally arranged nanorods (CMK-3 material) and nanotubes (CMK-5 material) made up of amorphous carbon. We report molecular dynamics results that aim at understanding the influence of (1) pore geometry and size and (2) pore loading, on the structural and dynamical properties of the confined IL. The effects of pore size, geometry and loading on the density profiles, orientation of the ions, and dynamics of the ions are also evaluated and discussed, as these molecular-level properties impact the macroscopic properties (e.g., electrical capacitance and resistance) of these systems.
5:15 AM - VV5.07
Modeling-based Study of the Effect of Diluents on Transport Properties of Ionic Liquid Electrolytes
David Binion 1 Soumik Banerjee 1
1Washington State University Pullman USA
Show AbstractLithium ion batteries are widely used as a power source for portable devices in the consumer electronics market. However, the highest energy storage capacity achieved by a state-of-the-art Li-ion battery is too low to meet current demands in larger applications such as in the automotive industry. The limitation is due, in part, to the limited ionic conductivity of currently used organic electrolytes coupled with their volatility and flammability, which raises safety concerns. The development of new generation of Li ion batteries with significantly improved energy storage would require the selection of novel electrolyte materials with improved performance without compromising on safety standards. Room temperature ionic liquids (IL) possess unique properties, such as low vapor pressure and non-flammability, making them promising alternatives for use as Li battery electrolytes. However, IL&’s often exhibit a great degree of ion association resulting in multiple anions coordinating with a single Li ion. Such enhanced coordination produces negatively charged clusters which can greatly reduce the mobility of Li and thus degrade the performance of IL electrolytes. Addition of organic diluents has been shown to enhance the transport properties of Li within IL&’s. In this computational study, molecular dynamics (MD) simulations have been used to investigate the effect of such additives on the diffusion of Li through the pyrrolidinium based N-methyl-N-propylpyrrolidinium bis(trifluoro- methanesulfonyl)imide (mppy+TFSI-) ionic liquid. Ab initio charge calculations were performed using the second order Moller-Plesset (MP2) perturbation theory with the 6-31G(d) basis set to determine the partial charges on various atoms of the ionic liquid and diluents. Simulations of neat Li-doped ILs were performed using the Optimized Potentials for Liquid Simulations (OPLS) force field and the calculated partial charges and material properties, such as density and self-diffusion coefficients, were determined and compared to experimental data to validate our model. The relative errors of our simulated self-diffusion coefficients compared to experimental values ranged from 7.7-10.3%. In order to investigate the effect of diluents, systems comprising IL, Li-TFSI salt and the solvents tetrahydrofuran (THF), vinylene carbonate (VC) and ethylene carbonate (EC) were simulated at various concentrations and over a wide temperature range. The results indicate that the diluent molecules, such as THF, associate with the Li ions and reduce the number of anions coordinating with Li thus improving the diffusion of Li. Both the size and charge density of these clusters determine the extent to which they improve the mobility of Li ions. The use of alternative additives such as methyltetrahydrofuran and dioxane will be explored in future studies to identify suitable additives that maximize the diffusive properties of Li within IL&’s and hence improve their ionic conductivity.
5:30 AM - VV5.08
Surface Smoothing of Glass Substrate by Irradiation of Ionic Liquid Ion Beams
Mitsuaki Takeuchi 1 Takuya Hamaguchi 1 Hiromichi Ryuto 1 Gikan H Takaoka 1
1Kyoto University Kyoto Japan
Show AbstractPolyatomic ion beam characterized by equivalently high current with low energy is an important technology not only for ultra-shallow ion-implantation, but also for surface modifications, e.g. oxidizing, redoxizing, coating, sputtering, roughening, and smoothing. These effects are induced by physical and/or chemical interactions among surfaces and many kinds of functional groups included in the incident polyatomic ions.
One of the most interested polyatomic ion is room temperature molten salts: ionic liquids(ILs). In the recent decade, ionic liquid ion source (ILIS) has been reported by several groups toward applications to electronic space propulsion, focused ion beam processing, probing ions in secondary ion mass spectroscopy. Ion order to improve the IL beam stability, we has developed a field-type ILIS made of carbon tip embedded with carbon felt, because the carbon has a good wettability of ILs at room temperature without any surface treatment[1]. Using the ILIS, we obtained many types of IL ion beam: positive ion beam with pure cations, negative ion beam with pure anions, and positive/negative cluster ion beams containing cation-anion pairs[2]. This leads to possibility for charge-up-less modification of insulating substrates such as a glass, which has been widely used for electronic and optical devices as seen in touch screens. In this study, irradiation effects on an non-alkali glass substrate by IL ion beams extracted from the developed ILIS were investigated.
1-butyl-3-methylimidazolium hexafluorophosphate(BMIM-PF6) and 1-ethyl-3-methylimidazolium tetrafluoroborate(EMIM-BF4) was used for the ion source liquid. Positive and negative ion beams from the developed ILIS with porous emitter were irradiated to a borosilicate glass substrate (Matsunami, compatible Corning #7059). The positive ion beam was accelerated to plus several kV, and the negative ion beam was also accelerated to minus several kV. The irradiations ware carried out under a fluence range from 1e13 to 1e15 ions/cm2, which was assumed as a single charge ion.
Surface roughness(arithmetic average) of the glass substrate irradiated with BMIM-PF6 ion beams were decreased from 0.2 nm for an unirradiated glass to 0.1 nm for the irradiated glass. The surface smoothing was clearly observed for lower acceleration voltage.
References
[1] M. Takeuchi, H. Ryuto, G.H. Takaoka, AIP Conference Proceedings 1321 (2011) 456.
[2] M. Takeuchi, T. Hamaguchi, R. Ueda, H. Ryuto, G.H. Takaoka, in:, IUMRS-International Conference on Electronic Materials IUMRS-ICEM, September, at Pacifico Yokohama, Yokohama, Japan, (2012).
Wednesday AM, April 03, 2013
Marriott Marquis, Golden Gate Level, Salon C2
9:30 AM - *VV4.01
Confined Ionic Liquids within Host Networks: From Intensive ILs Properties to Solid Devices
Aurelie Guyomard-Lack 1 Pierre-Emmanuel Delannoy 1 Jean Le Bideau 1
1Universitamp;#233; de Nantes Nantes Cedex 3 France
Show AbstractIonic liquids (ILs) have been the focus of a rapidly growing number of studies in materials science since early 2000&’s. Their liquid state is advantageous for their properties but often prevents their applications in devices which most often need solid state shaping. Thus, several approaches to get round this drawback are under investigation. On one hand, among these approaches, we have developped sol-gel routes to inorganic networks confining the IL : a silicon alkoxide precursor, for instance, is solvated in an IL, in which occurs subsequently a sol-gel process. The resulting monolithic silica shows an opened 3D interconnected mesoporosity, in the pores of which the IL stays confined, namely an ionogel. The solid obtained is thus endowed with properties of the choosen IL (non volatility, ionic conductivity and so on) simultaneously with those of a robust silicon oxide host backbone. On the other hand, similar sol-gel routes but associated with specifically designed polymers permits to enhance further the mechanical properties and shaping of the material confining the ILs.
The resulting ionogels and derived materials show striking properties. The synergetic associations allow most often to lower the melting point of IL as well as to increase the ionic transport. It will be shown that the bicontinuous interface and the confinement at nanoscale are modifying advantageously intensive properties of ILs. The conclusions are supported by results of studies with impedance spectroscopy and QENS, relaxometry, PGSE spectroscopies with show complementary characteristic time and space scales.
Among several potential applications, we will focus on lithium batteries and sensors. The macroscopic observation of the properties of these solid devices shows either equal or superior properties as referred to genuine ILs.
10:00 AM - VV4.02
Electroposition in Ionic Liquid of Si and Ge Related Nanowires (NWs) and Nanotubes (NTs)
Jeremy Mallet 1 Karine Namur 1 Florie Martineau 1 Michel Troyon 1 Michael Molinari 1
1University of Reims Champagne Ardenne Reims France
Show AbstractSilicon and Germanium NanoWires (NWs) or NanoTubes (NTs) have numerous applications in hydrogen storage, gas sensing, field emission, Li-ion Batteries, optoelectronics and so on. However, the preparation of silicon and germanium still requires constraining deposition conditions such as high vacuum and high preparation and the control of the geometry, composition (alloying or doping for example) is time consuming as it involves the development of one growing process per materials. Thus, it is not easily transposable to a future industrial large scale synthesis. In consequence, finding an alternative method for growing such NWs or NTs of different composition at a low cost, under room-temperature conditions and with easier growing process is a real challenge in the next few years.
In 2008, our group shows the possibility of growing Si NWs through a simple, innovative, original and alternative technique: electrodeposition in Room Temperature Ionic Liquids (RTILs) which enables to prepare silicon at room temperature and under atmospheric pressure. Thanks to this study we show an improvement of the method to grow well organized Si, Ge NWs but also NTs at a large scale and SiGe alloy NWs or even Er doped SiNWs.
While it is impossible to electrodeposit silicon using aqueous solvents, the wide electrochemical window of several RTILs compared to water makes possible the electrodeposition of Si, Ge, SiGe alloys or doped-Si materials. The simultaneous use during the growth of polymer or alumina membranes with pores of controlled diameters, lengths and densities lead to the growth of NWs with diameters between 15 and 400 nm.
By using RTILs and membranes, it is possible to grow pure Si and Ge NWs but also SiGe alloy NWs with various compositions and Si:Er doped NWs only by controlling the ratio between SiCl4, GeCl4 or ErCl3 in the solution and the deposition potential which makes this method very competitive compared to classical PVD or CVD experiments. From an electrochemical point of view, an important difference between aqueous solvent and ionic liquid is the viscosity (it can be eighty times more viscous than water), strongly correlated to the ionic conductivity and ionic diffusion. Considering this, many characteristics of the synthesized nanostructures are influenced by the ionic diffusion of ions inside the nanopores. To have an influence on the diffusion regime, nanostructures have been grown at various temperature using different deposition regime (steady state current deposition or pulse deposition) with various membrane thickness and we have shown that it is also possible to grow NTs instead of NWs by carefully choosing the growth parameters.
Finally, the correlation between the structural characterizations and the promissing optical properties of the NWs will be discussed.
10:15 AM - VV4.03
(Functional) Coatings by Metal Deposition from Ionic Liquids
Frank M Stiemke 1 Thomas J.S. Schubert 2 Maria Ahrens 2 Sven Sauer 2
1IOLITEC Inc. Tuscaloosa USA2IOLITEC GmbH Heilbronn Germany
Show AbstractIonic liquids (ILs) - new materials which consist entirely of ions and are liquid at temperatures below 100°C - show an interesting and often unique set of physical and chemical properties which cannot be found in other materials. Since most of these properties can be tuned towards a special application by rational design or adjusted through new combinations of anions and cations, these so called “designer solvents” offer new possibilities for various fields of applications.
In recent years many applications of ionic liquids in coating technologies have been developed.
One of the earliest published applications of ionic liquids in surface technologies was their use as electrolytes for the electro deposition of metals, especially those, which cannot be deposit from an aqueous electrolyte, on surfaces. It was shown that the choice of the ionic liquid could influence the surface structure of the deposited metal (e.g. micro- or nano-crystalline structures) and therefore the properties of the surface (e.g. bright and shiny finishes). Many different metals and metal alloys have been deposited from ionic liquids in the meantime and the first large scale process are on the way to commercialization. Right now, the deposition of aluminum is a very hot topic for decorative, consumer applications or corrosion protection. In addition, the deposition of nano-structured iron from IL-electrolytes allows iron to show unexpected properties and passivation behavior such as known from aluminum.
In this presentation we will give an overview on the application of ionic liquids in the area of coating technologies. We will present our own work on the electro deposition of aluminum and iron from IL-based electrolytes onto different metal substrates by using the suitable additives and deposition conditions.
11:30 AM - VV4.05
Morphologies and Ionic Conductivity in Polymerized Ionic Liquid Block Copolymers
Sharon Wang 1 Yuesheng Ye 2 Jae-Hong Choi 1 Yossef A. Elabd 2 Karen I. Winey 1
1University of Pennsylvania Philadelphia USA2Drexel University Philadelphia USA
Show AbstractPolymerized ionic liquid (PIL) block copolymers are nanostructured single-ion conductors that have many potential applications in electrochemical devices and serve as model systems for studying the effects of morphology on ionic conductivity. For a series of poly(methyl methacrylate-b-1-[2-(methacryloyloxy)ethyl]-3-butylimidazolium X-) (PMMA-b-PMEBIm-X-) diblock copolymers, we demonstrate that the strength of microphase separation is dictated by the counteranion (X- = OH-, Br-, or TFSI-). The degree of microphase separation was determined by differential scanning calorimetry (DSC) and small-angle X-ray scattering (SAXS). In the case of strongly microphase separated PIL block copolymers (X- = Br-, phi;PIL = 0.11-0.38), a sequence of morphologies is observed as the volume fraction of PIL increases, whereas for weakly microphase separated PIL block copolymers (X- = TFSI-), a microphase-separated morphology without long-range order is observed for all investigated compositions. A subset of these materials containing a hydrophilic PIL segment (X- = OH-, Br-) was characterized by in situ environmental SAXS. PMMA-b-PMEBIm-OH- (phi;PIL = 0.38) undergoes an order-disorder transition between 60 and 90 %RH and is disordered at 90 %RH, 30 °C, 50 °C, and 80 °C. In contrast, PMMA-b-PMEBIm-Br- (phi;PIL = 0.38) exhibits lamellar morphology at all investigated temperature and relative humidity conditions. Ionic conductivities of TFSI-, OH-, and Br-containing diblock copolymers were measured by electrochemical impedance spectroscopy (EIS) and are comparable at room temperature; however, at elevated relative humidity and temperature, the conductivities of OH- and Br-containing block copolymers (phi;PIL = 0.38) are as high as 30 and 6 mS/cm, respectively, exceeding the conductivities of their respective PIL homopolymers. Random copolymers based on the same monomeric units have disordered morphology and their conductivities are as much as two orders of magnitude less than that of the block copolymer of similar phi;PIL. Our findings demonstrate that microphase separation enhances ionic conductivity, in part by increasing the local ion concentration in conductive domains. The ionic conductivities of all three block copolymers were compared in terms of the morphology factor, f, and the implications will be discussed. The counterion, monomeric sequence (diblock vs. random), temperature, and environmental conditions (relative humidity) significantly influence both the morphology and ionic conductivity of PIL copolymers.
11:45 AM - VV4.06
Electrolyte-gated Transistors Based on Light-emitting Solution-processable Films
Jonathan J. Sayago 1 Yuvaraj Sivalingam 2 Mitesh Patel 1 Fabio Cicoira 1
1Ecole Polytechnique de Montreal Montramp;#233;al Canada2University of Rome Tor Vergata Rome Italy
Show AbstractOrganic Field Effect Transistors (OFETs) are the key elements for low-cost flexible electronics, such as flexible displays, sensor arrays and radio frequency identification tags[1]. The replacement of conventional gate dielectrics (e.g. SiO2) with an electrolyte gating media is an effective approach to induce high charge density, in the transistor channel, upon application of low electric bias [2,3]. We report on electrolyte-gated transistors based on thin light-emitting films of organic polymers, such as poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene], or metal oxides, such as zinc oxide. As the electrolytes, different ionic liquids were considered based on 1-butyl-3-methylimidazolium [BMIm] or 1-ethyl-3-methylimidazolium [EMIm] as the cation, and bis(trifluoromethylsulfonyl)imide [TFSI] or hexafluorophosphate [PF6] as the anion. The light-emitting properties of the films in contact with the ionic liquids were investigated, in inert atmosphere. The transistor electrical characteristics were correlated to the ionic conductivity, viscosity and ion size of the electrolyte.
[1] Klauk, H. Organic Electronics II. (John Wiley & Sons: 2012).
[2] M. J. Panzer & C. D. Frisbie, J. Am. Chem. Soc. 129, 6599 (2007).
[3] T. Takenobu, S.Z. Bisri, T. Takahashi, M. Yahiro, C. Adachi, Y. Iwasa Phys. Rev. Lett. 100, 066601 (2008).
12:00 PM - VV4.07
New Ionic Liquid Gels and Their Application in ZnO Field-effect Transistors
Stefan Thiemann 1 Swetlana Sachnov 2 Peter Wasserscheid 2 Jana Zaumseil 1
1Institute of Polymer Materials Erlangen-Nuremberg Germany2Chemical Reaction Engineering Erlangen-Nuremberg Germany
Show AbstractIonogels or ionic liquid gels are promising materials as electrolytes in low voltage, organic and inorganic field-effect transistors. They consist mainly of an ionic liquid (IL) and a gelator or blockpolymer in order to add mechanical stability and processability to the properties of the IL. The use of polymers like cellulose or cross-linkers like trimethylorthosilane (TMOS) leads to gelation of functionalized ionic liquids while preserving their electrochemical properties.
Here we present several novel imidazolium methylphosphonate ILs with polyethyleneglycol (PEG), silane, and carbon ester functionalities attached to the anion.[1] These are used to form solvent-free IL gels by adding cellulose (5-20 wt%) or trimethylorthosilane (TMOS). The obtained gels can be processed as thin films and conform to various device geometries. We compare the electrical (resistance, conductivity and specific capacitance), physicochemical (glass transition temperature and thermal stability) and rheological properties of gelated ILs with PEG, silane, and carbon ester groups. Temperature dependent studies of conductivity, resistance and capacitance of the ionogels give further insight into the nature of the obtained networks. We find that for imidazolium methylphosphonate ILs with cellulose as the gelator the mechanical stability and electrochemical performance depends strongly on the side chain functionalization of the IL anion. Conductivity as well as the capacitance decrease with increasing amount of the cellulose indicating a stiff network for high cellulose contents. The imidazolium methylphosphonate ILs with silane-functionalized anions show a linear correlation between the amount of TMOS and the mechanical stability as well as the electrochemical properties. Optimized gels can be processed by doctor-blading and act as dielectrics in electrolyte-gated ZnO-FETs. The obtained FETs show similar properties as devices gated with pristine ILs.[2]
References:
[1] Sachnov, S. J., et al., Chem. Commun., 2011, 47, 11234.
[2] Thiemann, S. et al., J. Phys. Chem. C, 2012, 116 (25), 13536-13544.
12:15 PM - VV4.08
Towards Ionic Liquid-based Thermoelectrochemical Cells for the Harvesting of Waste Heat
Theodore J Abraham 1 3 Jennifer M Pringle 2 3 Douglas R MacFarlane 1 3
1Monash University Clayton Australia2Monash University Clayton Australia3ARC Centre of Excellence for Electromaterials Science Clayton Australia
Show AbstractThe ability to efficiently harvest low level heat as a source of sustainable energy would make a significant contribution to reducing our current reliance on fossil fuels. Waste heat sources, such as those produced in industrial processes or through geothermal activity, are extensive, often continuous, and at present severely underutilised.
Thermoelectrochemical cells offer an alternative design to the traditional semiconductor-based thermoelectric devices and offer the promise of continuous and cheap operation at moderate temperatures, low maintenance and no carbon emissions.
Thermoelectrochemical cells utilise two electrodes, held at different temperatures, separated by an electrolyte containing a redox couple. It is the temperature dependence of the electrochemical redox potential that generates the potential difference across the device as a result of the applied temperature gradient. The magnitude of this temperature dependence is given by the Seebeck coefficient, Se.
Until recently, research into thermoelectrochemical cells had primarily focused on aqueous media, predominantly with the ferri/ferrocyanide redox couple.[1] However, the good thermal and electrochemical stability, non-volatility and non-flammability of many ionic liquids makes them promising alternative electrolytes for these devices. The use of ionic liquid electrolytes offers potential advantages that include increased thermoelectrochemical device efficiencies and lifetimes and the ability to utilise waste heat sources in the 100 - 200 oC temperature range.
Here we discuss our research into the influence of different ionic liquids on the Seebeck coefficients of a variety of redox couples,[2] and our progress towards the development of high efficiency ionic liquid-based thermoelectrochemical devices.
References
[1] R. Hu, B. A. Cola, N. Haram et al. Harvesting Waste Thermal Energy Using a Carbon-Nanotube-Based Thermo-
Electrochemical Cell, Nano Lett. 2010, 10: 838-846.
[2] T. J. Abraham, D. R. MacFarlane, J. M. Pringle, Seebeck coefficients in ionic liquids -prospects for
thermo-electrochemical cells, Chem. Commun., 2011, 47: 6260 -6262.
Symposium Organizers
Rico E. Del Sesto, Los Alamos National Laboratory
Sheng Dai, Oak Ridge National Laboratory
Robin D. Rogers, The University of Alabama
Yukihiro Yoshida, Meijo University
VV6
Session Chairs
Masayoshi Watanabe
Rico E. Del Sesto
Thursday AM, April 04, 2013
Marriott Marquis, Golden Gate Level, Salon C2
9:30 AM - VV6.01
Ionic Liquids as Low Cost and Versatile Organic Precursors for Carbonaceous Materials
Shiguo Zhang 1 Kaoru Dokko 1 Masayoshi Watanabe 1
1Yokohama National University Yokohama Japan
Show AbstractCarbon materials have attracted great interest, due to its wide applications in diverse areas such as environmental treatment and energy conversion and storage. The properties and performance are well known to depend on the carbonization methods and in particular, the precursor choices. Since most organic compounds are completely evaporated and decomposed before reaching 1000 oC, the current choice of precursors is limited to only a few conventional carbon sources, which can be classified into three typical types: (a) Natural or synthetic oligomers and polymers such as pitch, polyacrylonitrile, phenolic resins, and polyaniline, which are difficult to generate carbon nanocomposites and coatings. (b) Monomers that can be polymerized such as furfuryl alcohol, but a two-step procedure (pre-polymerization and carbonization) are necessary. (c) Other compounds with low molecular weight and high volatility, such as acetonitrile, can also be used with the help of harsh conditions such as chemical vapor deposition involving vacuum-based elaborate and careful fabrications, which are often too troublesome and too expensive. Although ionic liquids (ILs) were recently reported to be a new type of potential precursor for high N-content and highly conducting carbons due to its negligible volatility and molecular tunability,1-2 the reported ILs that can give substantial carbon yield is only limited to task-specific aprotic ILs containing cross-linkable intermediate, which are time-consuming for the synthesis and purification and highly expensive. Herein, we report that protic ILs (PILs) can be used as single, versatile, cheap and facile organic precursors for carbonaceous materials. In this case, the synthesis of PILs is very easy (only neutralization) and time-saving, resulting in generally low cost. Using the PILs concept, nearly all N-containing compounds, in particular those with low boiling points, which could not be used in conventional procedures, can be used as counter bases for PILs and can result in intrinsic N-doped carbon. Moreover, the chemical structure, pore structure, specific area, etc., of the resultant carbon materials can be easily tailored by choosing specific cation and anion.
1. J. Lee, X. Wang, H. Luo, G. Baker, and S. Dai, J. Am. Chem. Soc., 2009, 131, 4596-4597.
2. J. Paraknowitsch, J. Zhang, D. Su, A. Thomas, and M. Antonietti, Adv. Mater., 2010, 22, 87-92.
9:45 AM - VV6.02
Tough Block Copolymer Ion Gels via End-block Crosslinking
Yuanyan Gu 1 Sipei Zhang 2 Luca Martinetti 2 Keun Hyung Lee 2 Lucas D. McIntosh 2 C. Daniel Frisbie 2 Timothy P. Lodge 1 2
1University of Minnesota Minneapolis USA2University of Minnesota Minneapolis USA
Show AbstractBlock copolymer ion gels are a novel class of functional materials, which consist of an ABA triblock copolymer network swollen in an ionic liquid (IL). Previous studies have shown that ion gels can be used as gate dielectric materials for thin film transistors, and as a selective layer for CO2 separation membranes. Due to the high IL fraction, the mass transfer rate of ions (ionic conductivity) and gas molecules (gas permeability) is comparable to that of pure ILs. However, for applications in flexible electrochemical devices or high-pressure gas separations, it is desirable to enhance the mechanical strength of block copolymer ion gels. We introduce a novel type of ion gel which incorporates a chemically crosslinkable end-block. The cross-linkable ion gels are prepared through self-assembly of poly[(styrene-r-vinylbenzylazide)-b-ethylene oxide-b-(styrene-r-vinylbenzylazide)] (SOS-N3) and a selected IL 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMI][TFSA]). The poly(styrene-r-vinylbenzylazide) (PS-N3) end-blocks associate into micellar cores, whereas the PEO mid-blocks are solvated in [EMI][TFSA]. Upon further increase in temperature (200 °C), the azide groups in the cores can be chemically cross-linked, thereby locking the PS-N3 chains in the cores. Through this strategy, we can convert a physically crosslinked network to a chemically crosslinked one. The crosslinking kinetics has been systematically studied using rheology. After chemical crosslinking, the shear modulus and ionic conductivity remain the same, while the toughness and ultimate strength of ion gels have been significantly increased, by 800% and 460%, respectively.
10:00 AM - VV6.03
The Effect of Ionic Liquid Uptake and Self-assembled Conductive Network Composite Layers on Nafion(TM) Based Ionic Polymer Metal Composite Electromechanical Bending Actuators
Dong Wang 1 Reza Montazami 2 James Randy Heflin 1
1Virginia Tech Blacksburg USA2Iowa State University Ames USA
Show AbstractIonic polymer metal composite (IPMC) electromechanical bending actuators typically have a Nafion membrane as an ion conductive backbone. Conductive network composite (CNC) layers consisting of poly(allylamine hydrochloride) (PAH) and gold nanoparticles (Au NPs) have been formed via layer-by-layer (LbL) self-assembly on both sides of the Nafion membrane to enhance the ion transport and storage. The ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (EMI-Tf) has been used as the working electrolyte because of its high electrochemical stability window (>4V), thermal stability (>400 °C), high ionic conductivity and durability due to its almost zero vapor pressure. Under the external electric field, the cations and anions of the IL travel through the Nafion membrane, and accumulate in the CNC layers near the cathode and anode sides, respectively. The ion distribution within the actuator experiences a transition from a random, neutral mix to forced separation. Any imbalance (size, number, speed) between the cations and anions during this process will result in a differential swelling between the two sides of the actuator, resulting in a bending motion. With an applyied DC voltage (steady external electric field), the actuator shows a fast but smaller bending toward the anode followed by a slow but larger bending toward the cathode. This bi-directional bending behavior strongly suggests that the cations of the IL are smaller and faster under external electric field compared to the anions. By testing actuators all with 20 bilayers of CNC but different IL uptake, it is found that the maximum curvatures (both the cationic and anionic direction) are larger for the ones containing more IL (up to 35% wt.), which shows the crucial role played by the IL in the actuator. However, under the same conditions, the performance improvement of actuators without CNC layers saturates when the IL uptake reaches around 10% wt. This demonstrates the role of the CNC layers to provide a porous electrode with increased capacitance that thus accommodates accumulation of more ions near the electrodes, which in turn boosts the overall bending curvature of the actuator.
10:15 AM - VV6.04
Use of Ionic Liquids in Textile Finishing
Klaus Opwis 1 Torsten Textor 1 Jochen Stefan Gutmann 1
1Deutsches Textilforschungszentrum Nord-West gGmbH Krefeld Germany
Show AbstractThe dyeing of textile materials is still accompanied with several economic and ecological disadvantages resulting in a high consumption of water, energy and chemicals. In particular the dyeing of polyester fibers (PET) - beside cotton the most important fiber type - is accompanied with additional disadvantages, because it needs particular high process temperatures of more than 130 °C enabling the disperse dye stuffs to penetrate the fiber matrix. Therefore, an aqueous dyeing liquor would evaporate if open systems were used. Due to this, in praxis the dyeing of PET fibers is carried out in special pressure vessels, which results in another cost intensive factor. Thus, since many years textile researchers around the world are looking for alternative dyeing techniques for all kind of fiber types but especially for PET.
In this context, ionic liquids (IL) can play an important role. IL are salts with a melting point lower than 100 °C. IL excel by their extremely low vapor pressure and they are often thermo-stable far beyond 200 °C. Moreover, manifold substances, such as cellulose, keratin, and silicones, show high solubility in IL. In addition, preliminary work at DTNW has shown that IL can act as solvents for dyestuffs typically used for textiles.
Here, we present a new and innovative approach to dye synthetic and natural fibers in IL. This has been investigated for the commercially most important fibers PET, cotton and their blends, but also for other types, such as polyamide and polyacrylonitrile. Our dyeing procedure allows a pressure-free dyeing at high temperatures with minimal air pollution, which enables the textile industry to carry out their business with new methods avoiding high consumption of energy, water and chemicals.
As a second example, we report investigations on the deposition of cellulosic materials onto PET fibers from IL solutions to achieve cotton-like surfaces on the synthetic core fiber. Polyester is hydrophobic and chemically inert. It exhibits excellent mechanical properties and absorbs only low amounts of water. Thus, compared to hydrophilic cellulose textiles made of PET dry very fast. On the other hand, cotton has a lot of functional groups and is, therefore, comparably reactive, which is useful for further modifications. Since it produces a comfortable microclimate close to human skin it is widely accepted for manufacturing of apparel. The idea of our approach is to finish conventional PET fibers with cellulose to generate a new fiber combining positive properties of both materials. Our procedure allows the deposition of cellulose covering PET fibers. The resulting textiles show hydrophilic surfaces as known from cotton while the strength of the PET fiber is not affected. Because it exhibits excellent adhesion values and a highly reactive surface our cellulose modified PET fiber is of interest not only for apparel, since it promises the “cotton feeling” but also in the field of technical textiles.
10:30 AM - VV6.05
Ionic Liquids Confined in Porous Chalcogenides: A Molecular Simulation Study
Guido Ori 1 Massimo Celino 2 Carlo Massobrio 3 Benoit Coasne 1 4 5
1Institut Charles Gerhardt - ENSCM Montpellier France2ENEA Roma Italy3Institut de Physique et de Chimie des Matamp;#233;riaux de Strasbourg (UMR 7504-CNRS) Strasbourg France4Massachusetts Institute of Technology Cambridge USA5UMI 3466 CNRS - MIT Cambridge USA
Show AbstractObtaining in a controlled way chalcogenide-based materials, which exhibit a large surface area from ~10 to 500 m2/g made up of highly polarizable atoms, is an opened and very interesting challenge as it may lead to breakthroughs in various fields in which applications rely on the surface properties of host materials [1,2]. Ionic Liquids (ILs) are promising potential candidates as structuring agents to synthesize porous chalcogenides with controlled pore morphology and surface chemistry [3,4]. In the present work, a computational approach has been set up in order to obtain structural and dynamical insights into ionic liquids (ILs) confined in-between amorphous nanochalcogenide surfaces (nanopores).
By ab-initio Car-Parrinello Molecular Dynamics (CPMD) simulations, representative models of a-GeS2 surfaces have been obtained and compared with an amorphous GeS2 bulk model. After the insertion and equilibration, by classical MD simulations, of different amount of ILs molecules in-between two a-GeS2 surfaces, the structural and dynamical features of the internal ILs layer have been analyzed.
The present work represents, for our knowledge, the first computational study of ILs-Nanochalcogenide hybrid systems and opens the door to the complete understanding and optimization of the real application potentialities of these hybrid systems as promising catalysts or components in Li/Na-ions batteries, etc.
References
[1] S. Bag, P. N. Trikalitis, P. J. Chupas, G. S. Armatas, M. G. Kanatzidis, Science, 2007, 317, 490.
[2] G. S. Armatas, M. G. Kanatzidis, Nature Mater., 2009, 8, 217.
[3] S. Murugesan, P. Kearns, K. J. Stevenson, Langmuir, 2012, 28, 5513.
[4] Q. Zhang, I. Chung, J. I. Jang. J. B. Ketterson, M. G. Kanatzidis, J. Am. Chem. Soc., 2009, 131, 9896.
10:45 AM - VV6.06
Cycling Performance of Low-cost Lithium Ion Batteries with LiFePO4 Cathode
Hassan Srour 1 2 Helene Rouault 1 Catherine Santini 2
1CEA Grenoble France2Universitamp;#233; de Lyon 1 Lyon France
Show AbstractRoom temperature ionic liquids attract the attention of many scientists dealing with lithium-ion batteries. This interest is caused by their unique properties: wide liquid range, a wide electrochemical stability, good ionic conductivity, negligible volatility, non-flammability, etc. [1, 2]. The interest in lithium rechargeable batteries in electric vehicles (EVs) has been significantly increased in recent years [3]. The substitution of a common, organic carbonate-based electrolyte with an IL-based electrolyte leads to a significant improvement in system safety and the reduction of environmental risks and negative impacts on human health.
Transition metal oxides, such as LiNiO2 and spinel LiMnO4 have been studied as cathode materials in lithium batteries. These materials have shown good cyclibility and high capacity at potential (around 4 V versus Li/Li+). So far, LiCoO2 has been the main cathode material used in Li-ion batteries due to its high energy density. However, the questionable long term supply of cobalt material that is Co-free is needed rapidly to prepare for the future application Li-ion battery technology in HEV&’s. Since the demonstration of LiFePO4 by Padhi et al [4, 5] as potential cathode materials, considerable interest has been generated due to its safety, low cost and environmentally friendly nature [6, 7].
In this work, we assembled and tested low-cost lithium ion cells based on Cgr/LiFePO4 and Li4Ti5O12/LiFePO4 based on ionic liquids electrolyte. Two different lithium salts have been tested, LiNTf2 and LiPF6, vinylene carbonate used as co-additive to stabilize the graphite based electrode. The cycle performance, life, electrochemical stability of this cell is reported, along with some post-test, electrochemical diagnostics of the components after cycling. It worth to mention that lithium ion Cgr/LFP cells employing IL-electrolyte were realized and found to deliver a full discharge capacity, even more important, the cycling done at 60°C, which can&’t be safely achieved with conventional, organic solvent based electrolytes.
References
[1] M. Armand, F.Endres, D.R.Macfarlane, H.Ohno, B.Scrosati, Nat. Mater,; 8, 621 (2009).
[2] W.A. Van Schalkwijk, B. Scrosati, Advance in Lithium-ion Batteries, Kluwer Academic/Plenum Pulisher, (2002).
[3] V. Borgel, E. Markevich, D. Aurbach, G. Semrau, M. Schmidt, Journal of Power Sources,; 189, 331 (2009).
[4] A.K. Padhi, K.S. Nanjundaswany, and J. B. Goodenough, J. Electrochem. Soc., 144, 1188 (1997).
[5] A.K. Padhi, K.S. Nanjundaswany, C. Masquelier, S. Okada, and J. B. Goodenough, J. Electrochem. Soc., 144, 1609 (1997).
[6] H. Srour, N. Giroud, H. Rouault, C. Santini, ECS Trans, 41(41), 23 (2011).
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11:30 AM - *VV6.07
Ionic Liquids for Biomass Processing
Tom Welton 1 Agnieszka Brandt 1 S. M. Shahrul Nizan S. Z. 1 Jason P. Hallett 1
1Imperial College London London United Kingdom
Show AbstractAs a new chemicals industry based upon biomass sources emerges, there is an opportunity to create this on a sustainable basis from the outset. Ionic liquids have already shown their use in creating a more sustainable chemicals industry through the introduction of more sustainable processes. Using the knowledge that we have gained about the effects of solvent-solute interactions in ionic liquids, we have been developing these as solvents for lignocellulosic biomass processing.
Most approaches to the processing of biomass with ionic liquids have focused on the dissolution of cellulose. However, these potential processes have a number of drawbacks, greatest among these being their intolerance to water.
We present here our development of ionic liquids to fractionate lignocellulosic biomass via delignification, so that cellulose is made available for subsequent biological processing and the lignin component can be recovered for conversion into high value chemicals. We consider the optimum conditions for these reactions. We also present the use of ionic liquids to reduce the energy requirements of mechanical processing of the biomass.
12:00 PM - VV6.08
Self-templated Fluidic Precursor-based Carbons with Tailorable Pores and Their Application as Supercapacitor Electrodes
Pasquale F. Fulvio 1 Patrick C. Hillesheim 1 Shannon M. Mahurin 1 Gabriel M. Veith 2 Sheng Dai 1 3
1Oak Ridge National Laboratory Oak Ridge USA2Oak Ridge National Laboratory Oak Ridge USA3University of Tennessee Knoxville USA
Show AbstractCarbon materials having large specific surface areas and good electronic conductivities are highly desirable for energy storage applications as supercapacitors. Most research efforts have thus been concentrated in the development of routes to prepare carbons that combine both properties. Recently, the facile preparation of nitrogen-rich micro and mesoporous carbons via an ionothermal synthesis involving fluidic task specific ionic liquids (TSILs) with negligible vapor pressures, and high carbon yields, has been demonstrated. The latter have been prepared by using a cation, or anion having a cross-linkable moiety, with pores templated by the non-crosslinked counter ion. However, the ability to prepare large mesopores or hierarchical porous carbons was hindered by the size of the anion or cation that was not involved in the cross-linking reaction. In this work, we report a new family of TSILs capable of forming hierarchical microporous-mesoporous and microporous-macroporous carbons without the use of additional templates or additives. These compounds have bis-imidazolium cations linked by alkyl or phenyl-containing groups, with two terminal cyanide groups. Nitrogen adsorption at -196°C showed that carbons exhibit specific surface areas between 115-1200m2/g, micropores within 0.70-1.20nm, and mesopore widths exceeding 7nm. Short ethyl chains linking the imidazolium ions afforded microporous-mesoporous carbons, whereas increasing the chain length resulted in carbons with microporous-macroporous structures. Nitrogen contents as high as 7 at% were found by X-ray photoelectron (XPS). These carbons were tested as potential candidates for supercapacitor electrodes. The gravimetric capacitance values ranged between 100 and 160 F/g in aqueous KOH electrolyte, proportionally increasing with the specific surface area of these samples. Hence, this new family of TSILs is promising for the large scale preparation of carbons having well-developed mesopores, high specific surface areas and improved performance for electrochemical applications.
Acknowledgements: Work supported as part of Fluid Interface Reactions, Structures and Transport (FIRST) Center, Energy Frontier Research Center, U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences.
12:15 PM - VV6.09
High Temperature Solid-state Dye-sensitized Solar Cells Based on Organic Ionic Plastic Crystal Electrolytes
Feng Yan 1
1Soochow University Suzhou China
Show AbstractOrganic ionic plastic crystal, 1-Ethyl-1-methyl pyrrolidinium iodide (P12I), which possess a broad plastic phase was applied as solid-state ion conductors at room temperature. The synthesized P12I was doped with 1-ethyl-3-methylimidazolium iodide (EMII) to prepare the solid-state electrolytes, and employed for dye-sensitized solar cells (DSSCs), without using any volatile organic solvent. The fabricated solid-state devices give an overall power conversion efficiency of about 5.8 % at 80 °C under simulated radiation (50 mW/cm2). Furthermore, DSSCs based on PMII doped P12I ionic plastic crystal electrolyte show excellent long-time stability at 80 °C. These results demonstrate a feasible approach to solid-state DSSCs for practical outdoor application at high temperatures.
12:30 PM - VV6.10
A Novel PEO Based Poly (Ionic Liquid) Material for Energy Device Application
Heyi Hu 1 Wen Yuan 1
1Michigan State Univ. Lansing USA
Show AbstractA novel Poly (ionic liquid) based on PEO backbone was investigated as a promising electrolyte material for energy device like dye sensitized solar cells and lithium battery. This material, named as Poly(1-glycidyl-3-butylimidazolium bis(trifluoromethanesulfonyl)imide) (polyGBIM-TFSI) showed a high ionic conductivity (1.8 x 10-5 S/cm at 30 °C, 1.4 x 10-3 S/cm at 90 °C), corresponding to a low Tg of - 25 °C. In addition, it showed good thermal stability. The degradation temperature was higher than 300 °C. Furthermore, to obtain higher conductivity, a series of copolymer with different amounts of 1-glycidyltriethylene glycol monomethyl ether was synthesized. Copolymer with 1:1 molar ratio showed the highest conductivity, 1.2 x 10-4 S/cm at 30 °C, 5.0 x 10-3 S/cm at 90 °C, which corresponded to a lower Tg of - 41 °C.
12:45 PM - VV6.11
Magnetism and Paramagnetism in Metal-based Ionic Liquids
Rico E Del Sesto 1 Katherine S Lovejoy 1 Todd C Monson 2
1Los Alamos Natl Lab Los Alamos USA2Sandia National Laboratory Albuquerque USA
Show AbstractParamagnetic ionic liquids (ILs) have been around for decades, but their magnetic properties have been generally overlooked until recent reports of the manipulation of ILs via magnets at room temperature. The liquid nature of ILs makes them unique in their potential applications and magnetic behavior in non-ordered systems. There is now growing interest in the magnetic properties of ILs, but confusion exists whether ordered magnetic behavior as compared to general paramagnetic behavior exists. Herein we present examples of paramagnetic and ordered magnetic behavior, the latter of which only exists at low temperatures. We have synthesized room temperature ionic liquids containing transition metal and lanthanide halide-based anions, paired with a glass-forming phosphonium cation [R3R&’P]+. With lanthanide ILs, interesting behavior is observed for the ILs with deviations below 50K, and is likely the result of formation of small metal-halide clusters in the IL during glass formation, resulting in spin glass-like magnetic behavior.
Los Alamos National Laboratory is operated by Los Alamos National Security, LLC, for the National Nuclear Security Administration of the U.S. Department of Energy under contract DE-AC52-06NA25396. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.