• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.117-117
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• 2015

Availability of X-ray photoelectron spectroscopy (XPS) for the identification of ionic liquids (ILs) was tested. Commercially available ionic liquids (1-butyl-3-methyl imidazolium tetrafluoroborate ([BMIM] $BF_4$), (1-butyl-3-methyl imidazolium trifluoromethanesulfonate ([BMIM] OTf), (1-butyl-3-methyl imidazolium hexafluorophosphate ([BMIM] $PF_6$), 1-hexyl-3-imidazolium hexafluorophosphate ([HMIM] $PF_6$), and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM] $Tf_2N$) were qualitatively and semi-quantitatively analyzed with XPS. In order to confirm whether the results of XPS were correct, conventional method such as a nuclear magnetic resonance (NMR) was performed. After the XPS results were convinced by NMR, we synthesized ILs (1-(4-sulfonic acid) butyl-3-butylimidazolium trifluoromethanesulfonate ([SBBIM] OTf), 1-(4-sulfonic acid) propyl-3-methylimidazolium trifluoromethanesulfonate ([SPMIM] OTf), and 1-(4-sulfonic acid) propyl-3-butylimidazolium trifluoromethanesulfonate ([SPBIM] OTf) and analyzed it with XPS and NMR as well. It was successful the usage of XPS to analyze ILs without any purification processes.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2633-2636
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• 2011

A new type of ionic liquid based on N-(3-aminepropyl)imidazolium iodide, called IIQAI, which consists of imidazolium and quaternary ammonium salt, and APII-(hydroxyethyl, propyl, hexyl) were synthesized and used as ionic liquid in dye-sensitized solar cells. APII-hexyl is solid, whereas IIQAI, APII-(hydroxyethyl, propyl) are viscous liquids. The synthesized ionic liquid showed relative thermal stability compared to the commercial ionic liquid of DMII. Among them, IIQAI was more stable than the other ionic liquid because of the two salt groups. APII-hydroxyethyl, which contains two hydroxyl groups, showed low viscosity with good flow. New types of ionic liquids were examined by $^1H$-NMR spectroscopy, thermo gravimetric analysis (TGA). IIQAI enabled a solar energy conversion efficiency of 6.3%, which is slightly higher than that of the referenced (DMII, 6.2%).

• Bulletin of the Korean Chemical Society
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• v.27 no.6
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• pp.847-852
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• 2006

Imidazolium tetrafluoroborate ionic liquids having unsaturated aliphatic side chains were synthesized and characterized. Most of them are liquid at room temperature and all of them are stable up to $300{^{\circ}C}$. Some imidazolium tetrafluoroborates with an allylic side chain showed much wider voltage windows on the platinum electrode, better conductivities, and lower viscosities compared with the corresponding ionic liquids containing the saturated side chains.

• Clean Technology
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• v.20 no.4
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• pp.349-353
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• 2014

Succinic acid is an important precursor in industries producing biopolymers, pharmaceutical and food additives and green solvents. However, due to the high price of petroleum and the global $CO_2$ emission, the biological production of succinic acid from renewable biomass is a novel process due to the fixation of $CO_2$ into succinate during fermentation. In this study, aqueous two phase systems based on imidazolium ionic liquids/$K_2HPO_4$ were used as an effective separation and concentration process for succinic acid. Experimental results show that aqueous two phase systems can be formed by adding appropriate amount of imidazolium ionic liquids to aqueous $K_2HPO_4$ solutions in the presence of succinic acid. It can be found that the ability of imidazolium ionic liquids for phase separation followed the order [HMIm][Br]${\fallingdotseq}$[OMIm][Br]>[BMIm][Br]>[EMIm][Br]. The maximum value of extraction efficiency for succinic acid was about 90% and the amount of coextracted water into top phase is proportional to the chain length of cation in imidazolium ionic liquids. It was concluded that the aqueous two phase systems composed of imidazolium ionic liquids/$K_2HPO_4$ was effective for the selective extraction and concentration of succinic acid.

• Applied Chemistry for Engineering
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• v.23 no.5
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• pp.510-513
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• 2012

Palladium particles were synthesized by conventional chemical reduction method with ionic liquids. The size and shape of palladium particles were significantly affected by the cation parts of ionic liquids. This is mainly attributed to the different stabilities of the ionic liquid structure formed by the physical bond between the cation parts. Among ionic liquids with [$BF_{4}$] as an anion part, the hexyl substituent in the cation parts was more effective to synthesize palladium particles with the smaller size and more uniform shape.

• Analytical Science and Technology
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• v.24 no.6
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• pp.467-476
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• 2011

Solubility data of carbon dioxide ($CO_2$) in the imidazolium-based ionic liquids with methylsulfate anion are presented at pressures up to about 45 MPa and at temperatures between 303.15 K and 343.15 K. The ionic liquids studied in this work were 1-ethyl-3-methylimidazolium methylsulfate ([emim][$mSO_4$]), 1-butyl-3-methylimidazolium methylsulfate ([bmim][$mSO_4$]). The solubilities of $CO_2$ were determined by measuring the bubble point or cloud point pressures of the binary mixtures using a high-pressure equilibrium apparatus equipped with a variable-volume view cell. The equilibrium pressure increased very steeply at high $CO_2$ compositions. The $CO_2$ solubility in ionic liquids increased with increase of the total length of alkyl chains attached to the imidazolium cation of the ionic liquids. The phase equilibrium data for the $CO_2$ + ionic liquid systems have been correlated using the Peng-Robinson equation of state.

• Journal of the Korean Applied Science and Technology
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• v.31 no.3
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• pp.337-344
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• 2014

In this paper, we have examined the interaction of low bandgap polymer {poly(2-heptadecyl-4-vinylthieno[3,4-d]thiazole)(PHVTT)} with ionic liquids. Further, we have studied the temperature dependent interactions between the ionic liquids [tri-butyl methyl ammonium methyl sulfate ([TBMA][$MeSO_4$]), methyl imidazolium chloride ([MIM]Cl) and butyl methyl imidazolium chloride ([BMIM]Cl)] and polymer using UV-vis spectroscopy, FT-IR spectroscopy, photoluminescence (PL) spectroscopy, as a function of temperature at 21, 28, 32, $37^{\circ}C$. These experimental results suggest that interactions of polymer with ionic liquids ([MIM]Cl, [TBMA][$MeSO_4$]) showed weak interactions by increasing temperature but [BMIM]Cl has no significant effect with increase in temperature.

• Journal of the Korean Electrochemical Society
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• v.13 no.3
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• pp.198-202
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• 2010

Lithium co-polyelectrolyte-ionic liquid systems, using poly (lithium 2-acrylamido-2-methyl propanesulfonate; PAMPSLi) and polyvinyl formamid (PVF) were prepared and their electrochemical and physical properties were measured. The conductivity of co-polymer systems, PAMPSLi/PVF/N, N-dimethyl-N-propyl-N-butylammonium tricyanomethanide (PAMPSLi/PVF/$N_{1134}$TCM) and PAMPSLi/PVF/N, N-dimethyl-N-propyl-N-butylammonium dicyanamide (PAMPSLi/PVF/$N_{1134}$DCA) exhibited low viscosity ($N_{1134}$TCM:$N_{1134}$DCA 28.6cP, 28.7cP) and higher conductivity ($2.48{\times}10^{-3}Scm^{-1}$, $2.2{\times}10^{-3}Scm^{-1}$) than homopolymer system. The ionic conductivity PAMPSLi/PVF/1-ethyl-3-methyl imidazolium dicyanamide (PAMPSLi/PVF/emImDCA) exhibited $1.54{\times}10^{-3}Scm^{-1}$ and low viscosity (emImDCA: 28.09cP). High flexibility of imidazolium cation and dissociation of lithium cation from the co-polymer chains were affected by high conductivity and low viscosity.

• Bulletin of the Korean Chemical Society
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• v.25 no.10
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• pp.1531-1537
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• 2004

Twenty four thiol-functionalized ionic liquids based on imidazolium cation, 1-(12-mercaptododecyl)-3-alkylimidazolium salts, have been synthesized, and utilized to investigate the effects of alkyl-chain length and anion on the wettability of Au surfaces on the basis of self-assembled monolayers presenting [(CnSAMIM)X], where n = 1-6, X = Br, $BF_4$, $PF_4$ and $NTf_2$. Water wettabilities of the surfaces were measured as a water contact angle by contact angle goniometry. It was found that water wettability of the Au surfaces coated with imidazolium ions was largely dependent not only on counter anions but also on the length of alkyl chains. In the case of SAMs of N-alkylimidazolium ions having short length of N-alkyl chain (C1-$C_4$), anions played great role in determining water wettability of the surfaces.

• Applied Chemistry for Engineering
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• v.32 no.3
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• pp.277-282
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• 2021

Two hydrophobic imidazolium based ionic liquids including 1-benzyl-3-butylimidazolium hexafluorophosphate [BzBIM]PF₆ and 1-pentyl-3-butylimidazolium hexafluorophosphate [PBIM]PF₆ having the same anion and different cation parts were synthesized. The structural composition of these ionic liquids were confirmed with Fourier-transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (¹H-NMR). Their physiochemical properties such as viscosity, ionic conductivity and thermal stability alongside electrochemical potential window range for both ionic liquid electrolytes were characterized and compared to each other. The overall results revealed that [BzBIM]PF₆ has higher thermal and electrochemical stabilities and viscosity than that of [PBIM]PF₆ probably due to the presence of benzyl ring in the imidazolium cation providing strong intermolecular π-π interactions.