• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.273-273
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• 2006

The encapsulation of volatile organic electrolytes is a major challenge in practical applications of the DSSC. Ionic liquid (IL) within polymer electrolytes is an attractive candidate for replacement. Here we used a low viscosity ionic liquid 1-ethyl 3-methylimidazolium thiocyanate in order to modify ionic conductivity (${\sigma}$) of polymer electrolyte ($PEO:Kl/l_{2}$) and hence DSSC efficiency. The doping of IL enhanced ${\sigma}$ and attained maximum (${\sigma}=7.62{\times}10^{-4}S/cm$) at 80 wt% of IL concentration. Beyond this it was harder to get stable films. XRD confirmed that the intensity of the sharp PEO crystalline peaks decreased when IL was added. The DSC studies confirmed the reduction in crystallinity by adding ionic liquid.The efficiency of solar cell using aforesaid material was 0.6 % at 1 sun irradiation.

• Applied Chemistry for Engineering
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• v.27 no.1
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• pp.86-91
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• 2016

Three amorphous silicas and SBA-15 were employed as supports, which were capable of confining ionic liquid (IL) and metallocene in the nanopore. Ionic liquid functionalized silica was prepared by the interaction between the chloride anions of 1,3-bis(cyanomethyl)imidazolium chloride and the surface OH groups. Metallocene and methylaluminoxane (MAO) were subsequently immobilized on the ionic liquid functionalized silica for ethylene polymerization. The metallocene supported on ionic liquid functionalized XPO-2412 and XPO-2410 having a larger pore diameter compared to SBA-15 showed higher activity than that of using supported catalyst without ionic liquid functionalization. However, the activity of metallocene supported on SBA-15 decreased after ionic liquid functionalization, suggesting that the diffusion of ethylene monomer and cocatalyst to the active site of nanopore was restricted during ethylene polymerization. This could be resulted from significant reduction of the pore diameter due to the immobilization of ionic liquid and $(n-BuCp)_2ZrCl_2$ and MAO. The effect on polymerization activity in accordance with the concentration of hydroxyl groups on the surface was also investigated. The polymerization activity increased as the concentration of hydroxyl groups on amorphous silica increased. The polymerization activities of metallocene supported on silica showed the similar trend after ionic liquid functionalization.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.492-497
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• 2008

The solubility of carbon dioxide in ionic liquids and amine solvents has been investigated in gas-liquid absorption equilibrium reactor. Absorption capacity and kinetics of $CO_2$ with $CO_2$ pressure and absorption time in 9 different ionic liquids and 2 kinds of amine solvents were evaluated. In order to understand the effect of ionic type, we changed the cation or anion of ionic liquids. $CO_2$ absorption capacity and absorption rate of amine solvents were higher than those of ionic liquids. $CO_2$ absorption capacity of [emim][$Tf_2N$], $0.14molCO_2/mol\;IL$ at 1 bar, was the highest among the ionic liquids. $CO_2$ absorption capacity of ionic liquid steeply decreased with increasing temperature. Anion of ionic liquid dominates interaction with $CO_2$ and cation plays secondary role.

• Journal of Electrochemical Science and Technology
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• v.10 no.2
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• pp.177-184
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• 2019

An electrochemical detection method for capsaicin has been developed using ionic liquid (IL) doped graphene-titania-Nafion composite-modified electrode. The combination of IL (1-hexyl-3-methylimidazolium with hexafluorophosphate counter ion) in the composite-modified electrode resulted in a significantly increased electrochemical response for capsaicin compared to that obtained at the corresponding electrode without IL. The increased electrochemical signal could be ascribed to the decreased electron transfer resistance through the composite film and also to the effective accumulation of capsaicin on the electrode surface due to ${\pi}-{\pi}$ interaction of the imidazole groups of IL with the aromatic rings of capsaicin. The present IL composite-modified electrode can detect capsaicin with a concentration range from $3.0{\times}10^{-8}M$ to $1.0{\times}10^{-5}M$ with a detection limit of $3.17{\times}10^{-9}M$ (S/N = 3). The present sensor showed good reproducibility (RSD = 3.2%).

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.973-976
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• 2011

The addition of organic ligand (${\beta}$-diketone or heterocyclic compound) to the europium (III)-containing ionic liquid resulted in bright luminescent soft materials with the molar ratio of europium/ionic liquid (IL)/ligand being 1:3:1 that exhibit bright red light under UV lamp. The luminescent properties such as emission features and lifetime of $^5D_0$ $Eu^{3+}$ excited level are dependent on the organic ligands. The materials were characterized by FT-IR and luminescence spectroscopy. The data shows that at least parts of the ILs (carboxylic acid) are replaced with ${\beta}$-diketone ligand rather than the formation of europium complex with the molar ratio of $Eu^{3+}$:IL: ligand being 1:3:1, while no ILs could be replaced by the heterocyclic ligand such as Bpy and Phen.

• Membrane Journal
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• v.30 no.3
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• pp.149-157
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• 2020

Ionic Liquid (IL) in the category of low-temperature molten salts with organic cation and organic/inorganic anion has shown great potentiality in CO₂ gas separation. CO₂ gas separation from flue gas by IL based membrane has been widely researched in recent years to overcome climate change and global warming. Membranes based on free standing polyionic liquid (PIL), blend of ionic liquid and composite ionic liquid membranes are discussed in this review. Introducing different IL monomers and tuning microstructure of PIL membrane and composite of PIL-IL to enhance mechanical properties of membranes with good CO₂ gas permeability and selectivity. Variations in cation and anions of monomer has great impact on the membrane gas separation performance.

• Membrane Journal
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• v.33 no.5
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• pp.240-247
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• 2023

Even among gas separation methods, CO₂ capture and separation via membranes is an ever-growing field, with many different membrane compositions continually being developed. Ionic liquid (IL) based composite membranes show excellent performance values in separating CO₂. Similarly, various copolymer/IL composite membranes also display improved performance. The addition of fillers such as graphene oxide to these copolymer/IL composite membranes shows a further enhanced version of these fillers, most likely due to the strong interactions that occur between ILs and organic fillers, which consequently improves factors such as the affinity, selectivity, and adsorption of CO₂. Copolymer/IL composite membranes utilizing a metal-organic framework (MOF) showed improved CO₂ permeability. This review discusses the study of various combinations of ionic liquid and copolymer composite membranes for carbon dioxide separation.

• Clean Technology
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• v.12 no.3
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• pp.128-137
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• 2006

The volume change of an ionic liquid and the phase separation behavior of room temperature ionic liquid(RTIL)/organic compound mixture in supercritical carbon dioxide were measured in a high pressure view cell. 1-Butyl-3-methylimidazolium hexafluorophosphate ([bmim][$PF_6$]) and 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][$BF_4$]) was used as ionic liquid(IL). and methanol and dimethyl carbonate were used as organic compound. For a fixed amount of [bmim][$PF_6$] the lower critical endpoint (LCEP) pressure, where the liquid phase is split, decreased as increasing the amount of organic compound. The LCEP pressure became higher as the water content of ionic liquid was higher. However, for water contents above a certain value, no LCEP was formed. LCEP appeared 1.0 MPa higher for a mixture with [bmim][$BF_4$] than with [bmim][$PF_6$]. There was almost no difference in the K-point pressures for different types of ionic liquid and for different amounts of organic liquid. When the concentration of ionic liquid([bmim][$PF_6$]) (IL/(IL+MeOH)) in the initial liquid mixture was larger than 5.9 mol% at the LCEP of the mixture, the volume of $L_1$ because larger than the volume of $L_2$. When it was smaller, however, the volume became smaller, too. The volume change of ionic liquid in the presence of carbon dioxide decreased as increasing the temperature, while it increased as increasing the pressure. For temperatures between 313.15 to 343.15K at 300 bar, it was about 123~125 % of the original volume.

• Applied Chemistry for Engineering
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• v.31 no.3
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• pp.305-309
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• 2020

In this study, a series of ionic liquids based electrolytes for lithium batteries were prepared by mixing the anion functionalized ionic liquid, [DMIm][MPEGP] (1,3-dimethylimidazolium (2-methoxy(2-ethoxy(2-ethoxy)))-ethylphosphite), with the lithium salt, LiTf₂N (lithium bis(trifluoromethanesulfonyl)imide), and the concentration of lithium salt was varied between 0 and 3.0 molar ratio. We observed the ionic mixtures became opaque and spontaneously aggregated to form a thermotropic ionic liquid crystal. Extensive spectroscopic examinations of the ionic liquid crystals were carried out to investigate their self-organized structures and the ion transport behavior depending on the concentration of lithium salt. An increase in the ionic conductivity was observed for the ionic liquid crystals related to the ability to form ion diffusion pathways along the ordered structures, resulting in improved electrochemical performances of lithium batteries.

• Clean Technology
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• v.20 no.4
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• pp.354-358
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• 2014

Ionic liquid (IL) is a salt presents in a liquid form at room temperature. Recently, it attracts huge attention due to its possibilities as a clean solvent, electrolyte, and catalyst. In the present work, the charging behavior of six different ILs were investigated using droplet contact charging phenomenon in a dielectric medium. Basically, the charging of an IL droplet can be explained by a perfect conductor theory. However, there were several different features depending on the species of ions of ILs, which requires rigorous molecular level modeling of charge transport through electrochemical reaction of IL. We hope the present results contribute to build up fundamental understanding of electrochemical charge transport of IL.