• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.2961-2965
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• 2012

Mesoporous carbons with tailored pore size were prepared by using sucrose as the carbon source and silicas as the templates. The silica templates were obtained from a hydroxypropyl-${\beta}$-cyclodextrin-silica hybrids using ammonium perchlorate oxidation at different temperatures to remove the organic matter. The structures and surface chemistry properties of these carbon materials were characterized by $N_2$ adsorption, TEM, SEM and FTIR measurements. The catalytic performances of these carbon materials were investigated through the reduction of nitroaromatic using hydrazine hydrate as the reducing agent. Compared with other carbon materials, such as active carbon, and carbon materials from the silica templates obtained by using calcination to remove the organic matter, these carbon materials exhibited much higher catalytic activity, no obvious deactivation was observed after recycling the catalyst four times. Higher surface area and pore volume, and the presence of abundant surface oxygen-containing functional groups, which originate from the special preparation process of carbon material, are likely responsible for the high catalytic property of these mesoporous carbon materials.

• Carbon letters
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• 제1권3_4호
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• pp.133-137
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• 2001

Mesoporous activated carbon fiber (ACF) was prepared from phenolic resin containing a small amount (0.1 wt %) of organic nickel complex through carbonization and steam activation. Microporous ACF as reference sample was also prepared from phenolic resin without agent. In both cases of the mesoporous ACFs and the microporous ACFs, the electric double layer capacitance of the nonaqueous electrolyte (0.5 M $TEABF_4$/PC or 1.0 M $LiClO_4$/PC) was not proportional to the BET specific surface area. This is owing to the low permeability of nonaqueous electrolyte or the low mobility of ion in narrow micropores. However, the mesoporous ACF showed higher double layer capacitance than the microporous (normal) ACF. This result suggests that the presence of many mesopores promotes the formation of effective double layer or the transfer of ion in the micropore.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3331-3335
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• 2014

We examine the potential use of disordered mesoporous carbon as a functional additive for confining dissolved Li-polysulfides and improving the cycling performance of Li-S batteries. To promote a better understanding of the correlation between the total pore volume of disordered mesoporous carbon and the cycling performance of Li-S batteries, a series of disordered mesoporous carbons with different total pore volumes are successfully synthesized using a commercial silica template. Based on the electrochemical and structural analyses, we suggest that the total pore volume of disordered mesoporous carbon is a predominant factor in determining its capability for either the absorption or adsorption of Li-polysulfides, which is primarily responsible for enhancing the cycling performance. The addition of disordered mesoporous carbon is also effective in enhancing the homogeneous distribution of active sulfur in the cathode, thereby affecting the cycling performance.

• Bulletin of the Korean Chemical Society
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• 제26권5호
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• pp.709-710
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• 2005

• Current Applied Physics
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• 제18권12호
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• pp.1480-1485
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• 2018

Mesoporous carbon-silica composites supported Pt nanoparticle catalysts (Pt/MCS) were firstly applied to the heterogeneous asymmetric hydrogenation of ethyl 2-oxo-4-phenylbutyrate (EOPB). A series of different silica contents were investigated in the fabrication of this mesoporous material. When the volume of added tetraethyl orthosilicate (TEOS) during the preparation of composites is 8 mL, Pt/MCS-8 holds carbon and silica as the main components and possesses relatively strong acidity, mesoporous structures with micropores, appropriate Pt nanoparticle size and high dispersibility showing by XRD, XPS, TPD, $N_2$ sorption and TEM. These properties cause its good catalytic performance in the heterogeneous asymmetric hydrogenation of EOPB with the enantiomeric excess value and conversion up to 85.6% and 97.8%, respectively.

• 한국산학기술학회논문지
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• 제13권4호
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• pp.1915-1922
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• 2012

본 연구는 SBA-15, MCM-41, MCM-48, KIT-6와 같은 메조포러스실리카를 다양한 조건에서 합성하고 이를 이용하여 CMK(Carbon Mesoporous Korea)를 합성한다. 합성된 CMK를 이용하여 메조포러스 구조의 전이금속체를 제조하였다. 각각의 메조포러스실리카에 따라 합성된 CMK의 특성을 분석하고 이를 이용하여 합성된 메조포러스 전이금속체의 특성을 질소흡탈착 등온선, SEM, 저각 X-선 회절분석으로 분석하므로써 최적의 메조포러스 전이금속체의 합성조건을 도출하였다, 실험 결과 가장 우수한 특성을 나타내는 메조실리카는 SBA-15이며, BET 분석으로 SBA-15로부터 합성된 메조포러스 구리 분자체의 비표면적은 $225m^2/g$, 기공크기는 2.91nm로 나타났다.

• Carbon letters
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• 제23권
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• pp.9-16
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• 2017

This paper introduces a nitrogen-doped ordered mesoporous carbon (NOMC) derived from glucosamine with hybrid capacitive behaviors, achieved by successfully combining electrical double-layer capacitance with pseudo-capacitance behaviors. The nitrogen doping content of the fabricated NOMC reached 7.4 at% while its specific surface area ($S_{BET}$) and total pore volume reached $778m^2g^{-1}$ and $1.17cm^3g^{-1}$, respectively. A dual mesoporous structure with small mesopores centered at 3.6 nm and large mesopores centered at 9.9 nm was observed. The specific capacitance of the reported materials reached up to $328Fg^{-1}$, which was 2.1 times higher than that of pristine CMK-3. The capacitance retention rate was found to be higher than 87.9% after 1000 charge/discharge cycles. The supplementary pseudocapacitance as well as the enhanced wettability and conductivity due to the incorporation of nitrogen heteroatoms within the carbon matrixes were found to be responsible for the excellent capacitive performance of the reported NOMC materials.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.221.2-221.2
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• 2011

In this study, we prepared the magnesium oxide decorated ordered mesoporous carbons processed by the reduction of magnesium oxide precursor on the CMK-3 surfaces in order to investigate the characterization and the effect on their carbon dioxide adsorption behaviors. The magnesium contents of the prepared samples were characterized using XPS. The textural properties of the prepared samples were investigated by $N_2$/77 K adsorption isotherms by BET equation. The carbon dioxide adsorption capacities of the prepared samples were investigated by the amounts of carbon dioxide adsorptions at 298 K and 1.0 atm. The results showed that the magnesium oxide on the CMK-3 surface enhanced interaction between carbon dioxide and adsorbents. Consequently, it was found that the magnesium oxide led to an increase in the carbon dioxide adsorption capacity of the CMK-3.

• Bulletin of the Korean Chemical Society
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• 제30권8호
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• pp.1778-1782
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• 2009

Mesoporous TS-1 catalysts were prepared via a nanocasting route using two different carbon template sources of CMK-3 and commercial carbon black. Products were characterized by XRD, UV-Vis spectroscopy, SEM, TEM, and $N_2$ adsorption- desorption measurement. The catalytic performances of the samples for allylchloride epoxidation and oxidative desulfurization of the representative refractory sulfur compounds, dibenzothiophene and 4,6-dimethyldibenzothiophene, were compared against those of conventional TS-1. Whilst the allychloride epoxidation activity for the mesoporus TS-1 samples were similar, mesoporous TS-1 exhibited significantly higher catalytic activities than conventional TS-1 in oxidative desulfurization.

• Bulletin of the Korean Chemical Society
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• 제29권2호
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• pp.413-416
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• 2008

A synthesis route to ordered mesoporous carbons with controllable nitrogen content has been developed for high-performance EDLC electrodes. Nitrogen-doped ordered mesoporous carbons (denoted as NMC) were prepared by carbonizing a mixture of two different carbon sources within the mesoporous silica designated by KIT-6. Furfuryl alcohol was used as a primary carbon precursor, and melamine as a nitrogen dopant. This synthesis procedure gave cubic Ia3d mesoporous carbons containing nitrogen as much as 13%. The carbon exhibited a narrow pore size distribution centered at 3-4 nm with large pore volume (0.6-1 cm3 g-1) and high specific BET surface area (700-1000 m2 g-1). Electrochemical behaviors of the NMC samples with various N-contents were investigated by a two-electrode measurement system at aqueous solutions. At low current density, the NMC exhibited markedly increasing capacitance due to the increase in the nitrogen content. This result could be attributed to the enhanced surface affinity between carbon electrode and electrolyte ions due to the hydrophilic nitrogen functional groups. At high current density conditions, the NMC samples exhibited decreasing specific capacitance against the increase in the nitrogen content. The loss of the capacitance with the N-content may be explained by high electric resistance which causes a significant IR drop at high current densities. The present results indicate that the optimal nitrogen content is required for achieving high power and high energy density simultaneously.