• 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.

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1562-1566
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• 2007

1-Alkenyl-2,3-dimethylimidazolium tetrafluoroborate ionic liquids having an olefinic substituent were synthesized and characterized. Among them, [AMMIm]BF4 with an allyl group showed lower viscosity, higher ionic conductivity, and a wider electrochemical window compared with its analogue having a saturated alkyl substituent. An EDLC with [AMMIm]BF4 showed better performance than that with [PMMIm]BF4, too.

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1567-1572
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• 2007

New pyrrolidinium and piperidinium bis(trifluoromethanesulfonyl)imide (TFSI) ionic liquids (ILs) having allyl substituents were synthesized and characterized. All of them are liquid at room temperature and stable up to 300 oC. The pyrrolidinium-based ILs showed better conductivities and lower viscosities than the corresponding piperidinium-based ILs. Among them, 1-allyl-1-methylpyrrolidinium TFSI showed the lowest viscosity of 52 cP, the highest conductivity of 5.7 mS cm?1, and the most negative cathodic voltage window of ?3.2 V (vs. Fc/Fc+) on a platinum electrode, which are the improved results compared to the corresponding analogue having a saturated substituent, 1-methyl-1-propylpyrrolidinium TFSI.

• 한국전기화학회:학술대회논문집
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• 2003.10a
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• pp.51-51
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• 2003

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.188-190
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• 2007

The MEA with the catalyst layer containing PtRu black and 60 wt. %Pt/C as their anode and cathode catalysts. For find to effect of carbon support, the MEA with platinum black for cathode catalyst was fabricated. The performance of the MEA with the catalyst layer containing (PtRu black:60 wt.% Pt/C) as their anode and cathode catalyst has shown competitively higher value than the performance of the MEA with the catalyst layer containing (PtRu black:Pt black) as their anode and cathode catalyst.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.169-171
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• 2007

A breaking layer was introduced to conventional decal transfer method in membrane electrolyte assembly fabrication for high catalyst transfer ratio. In this study, the modified decal transfer method with high catalyst transfer ratio was introduced and its performance is studied. The structural features of electrodes made by decal method were investigated using scanning electron microscopy and current-voltage polarization measurement.

• Journal of Electrochemical Science and Technology
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• v.1 no.1
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• pp.19-24
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• 2010

Alloying degree is an important structural factor of PtRu catalysts for direct methanol fuel cells (DMFC). In this work, carbon supported PtRu catalysts were synthesized by reduction method using anhydrous ethanol as a solvent and $NaBH_4$ as a reducing agent. Using anhydrous ethanol as a solvent resulted in high alloying degree and good dispersion. The morphological structure and crystallanity of synthesized catalysts were characterized by X-ray diffraction (XRD), high resolution transmission electron microscope (HR-TEM). CO stripping and methanol oxidation reaction were measured. Due to high alloying degree catalyst prepared in anhydrous ethanol, exhibited low onset potential for methanol oxidation and negative peak shift of CO oxidation than commercial sample. Consequently, samples, applying ethanol as a solvent, exhibited not only enhanced CO oxidation, but also increased methanol oxidation reaction (MOR) activity compared with commercial PtRu/C (40 wt%, E-tek) and 40 wt% PtRu/C prepared in water solution.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.356-359
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• 2006

고분자전해질 연료전지의 MEA를 CCM (Catalyst Coated Membrane) CCS(Catalyst Coated Substrate) 형태로 각각 제조하고 백금담지 비율이 서로 다른 백금 담지촉매를 각각 적응하여 MEA를 CCM형태로 제조하여 단위전지 성능평가를 수행하였다 백금담지 비율이 다른 촉매를 적용한 CCM형태 MEA의 표면을 SEM (scanning electron microscopy)으로 분석하였으며, 단위전지 성능평가를 수행하는 동시에 EIS (Electrochemical Impedance Spectroscopy)를 통하여 MEA의 저항을 분석하였다. 고분자전해질 연료전지의 성능은 MEA의 제조방법과 백금담지 촉매의 백금담지비율에 따라 크게 변함을 확인 할 수 있었다.

• Journal of Hydrogen and New Energy
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• v.23 no.6
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• pp.647-653
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• 2012

We have investigated the kinetics and activity of waste catalysts for steam-lignite gasification. Waste catalysts I, II, III and reference $K_2CO_3$ were used and physical mixed with a coal. The gasification experiments were carried out with the low rank coal loaded with 1 wt% and 5 wt% catalyst at the temperature range from 700 to $900^{\circ}C$ using thermobalance reactor. It was observed that the carbon conversion reached almost 100% regardless of the kinds of catalysts at $900^{\circ}C$. The shortest time to reach the designated conversion was obtained for 1 wt% waste catalyst II and 5 wt% $K_2CO_3$ at $900^{\circ}C$. The gasification reaction rate constant increased with increasing the temperature. Highest rate constant was obtained with $K_2CO_3$ at $900^{\circ}C$. The lowest activation energy was 69.42 kJ/mol for 5 wt% waste catalyst II. The waste catalyst had an influence on the reduction of activation energy.

• 한국전기화학회:학술대회논문집
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• 2005.04a
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• pp.43-43
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• 2005