• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.14-17
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• 2012

Submicron silver particles were synthesized by chemical reduction with various room temperature ionic liquids. The size and distribution of silver particles were significantly affected by the anion type of ionic liquids and this is mainly attributed to the different abilities of the anions to coordinate with the silver particle, leading to various coagulation of silver particles. Among ionic liquids, 1-butyl-3-methylimidazolium hexafluorophosphate was the most effective to synthesize submicron silver particles.

• Journal of the Korean Electrochemical Society
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• v.15 no.1
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• pp.35-40
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• 2012

The composite membranes using Nafion as matrix and 1-ethyl-3-methylimidazolium tetracyanoborate (EMITCB) as ion-conducting medium in replacement of water were prepared and characterized. The amount of EMITCB in Nafion varied from 30 to 50wt%. The composite membranes are characterized by ion conductivity, thermogravitational analyses (TGA) and small-angle X-ray scattering (SAXS). The composite membranes containing EMITCB of 40wt% showed the maximum ionic conductivity which was ~0.0146 S $cm^{-1}$ at 423.15 K. It is inferred that the decrease in ionic conductivity of all the composite membranes might be due to the decomposition of a tetracyanoboric acid formed in the composite membranes. The results of SAXS indicated that the ionic clusters to conduct proton in the composite membranes were successfully formed. In accordance with the results of ionic conductivity as a function of a reciprocal temperature, SAXS showed a proportional decrease in scattering maximum $q_{max}$ as the amount of EMITCB increases in the composite membranes, which results in the increase in ionomer cluster size. The TGA showed no significant decomposition of the ionic liquid as well as the composite membranes in the range of operating temperature ($120-150^{\circ}C$) of high temperature proton exchange membrane fuel cells (HTPEMFC). As a result, EMITCB is able to play an important role in transferring proton in the composite membranes at elevated temperatures with no external humidification for proton exchange membrane fuel cells.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.342-346
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• 2013

In this study the cycloaddition of glycidyl methacrylate (GMA) and $CO_2$ using ionic liquid as catalyst was performed for the technology of $CO_2$ reduction. The structure of synthesized cyclic carbonate, [2-oxo-1,3-dioxolan-4-yl]methacrylate (DOMA) was analyzed and confirmed by FT-IR and $^1H$-NMR. The change in conversion with respect to reaction time was investigated using $^1H$-NMR. Interestingly, the ionic polymerization of vinyl groups and crosslinking reaction between cyclic carbonate rings of DOMA were observed following completion of cycloaddition.

• Journal of the Korean Electrochemical Society
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• v.14 no.1
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• pp.38-43
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• 2011

Because the ionic liquid added with Propylene carbonate(PC) at room temperature has lower viscosity than original, we considered electrochemical behavior of it in EDLC. The ionic liquid without PC which does not have ions has no problem in capacity since it has enough ions. The electrolyte resistance was decreased with decreasing viscosity. As a result of identifying high current discharge capacity, we observed that the ionic liquid had capacity of 73.12% at current density of $80\;mA/cm^{-2}$, but it increased to 81.94% at PC content of 40 vol%.

• Proceedings of the Korean Vacuum Society Conference
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• 2006.08a
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• pp.89-89
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• 2006

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.05a
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• pp.265-266
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• 2018

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2017.05a
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• pp.334-335
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• 2017

• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.271-276
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• 2011

We investigated the possibility of introducing functional groups without damaging surface polymeric chains through the treatment of a polypropylene(PP) film immersed in liquid phase using an atmospheric pressure plasma with large area. The ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate: $[BMIM]^{+}[BF_{4}]^{-}$- was successfully applied for generating stable plasmas in the plasma-solution system. We successfully treated the film surface using the plasma-solution system and confirmed various oxygen-containing functional groups formed on the surface of PP film. The surface free energy of PP film was increased with increasing plasma treatment time and power. It also showed a maximum value at the PP sample treated in the ionic liquid solution of 1.5 M. ATR-FTIR analyses revealed the increase of various carbonyl groups(1,726 $cm^{-1}$, 1,643 $cm^{-1}$) and OH groups$(3,100{\sim}3,500\;cm^{-1})$ after plasma treatment of PP film, and XPS also supported the ATR-FTIR result.

• Clean Technology
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• v.17 no.1
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• pp.37-40
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• 2011

Some ionic liquids are suitable for catalysts and solvents which are applicable to $CO_2$ fixation reaction converting $CO_2$ to carbonate. Using the ionic liquids, the synthesis process will become greener and simpler because of easy catalyst recycling and unnecessary use of volatile and harmful organic solvents. In this work, the synthesis of propylene carbonate from propylene oxide using carbon dioxide and ionic liquids were measured at high pressures up to ~140 bar and at temperatures between $60^{\circ}C$ and $80^{\circ}C$. As a results, we found the optimum condition and obtained the maximum yield under that condition.

• Carbon letters
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• v.28
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• pp.47-54
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• 2018

High surface carbon aerogels with hierarchical and tunable pore structure were prepared using ionic liquid as carbon precursor via a simple salt templating method. The as-prepared carbon aerogels were characterized by nitrogen sorption measurement and scanning electron microscopy. Through instant visual observation experiments, it was found that salt eutectics not only serve as solvents, porogens, and templates, but also play an important role of foaming agents in the preparation of carbon aerogels. When the pyrolyzing temperature rises from 800 to $1000^{\circ}C$, the higher temperature deepens the carbonization reaction further to form a nanoporous interconnected fractal structure and increase the contribution of super-micropores and small mesopores and improve the specific surface area and pore volume, while having few effects on the macropores. As the mass ratio of ionic liquid to salt eutectics drops from 55% to 15%, that is, the content of salt eutectics increases, the salt eutectics gradually aggregate from ion pairs, to clusters with minimal free energy, and finally to a continuous salt phase, leading to the formation of micropores, uniform mesopores, and macropores, respectively; these processes cause BET specific surface area initially to increase but subsequently to decrease. With the mass ratio of ionic liquids to salts at 35% and carbonization temperature at $900^{\circ}C$, the specific surface area of the resultant carbon aerogels reached $2309m^2g^{-1}$. By controlling the carbonization temperature and mass ratio of the raw materials, the hierarchically porous architecture of carbon aerogels can be tuned; this advantage will promote their use in the fields of electrodes and adsorption.