• Carbon letters
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• 제18권
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• pp.84-89
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• 2016

• Bulletin of the Korean Chemical Society
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• 제26권10호
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• pp.1585-1587
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• 2005

• 대한화학회지
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• 제55권4호
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• pp.666-672
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• 2011

Vanadium 치환체인 polyoxometalate 1, [Cu(2,2'-bipy)]$[Cu(2,2'-bipy)_2]_2[PMo_8V_6O_{42}]{\cdot}1.5H_2O$을 가지고 있는 inorganicorganic complex의 촉매 활성도를 Biginelli 반응에 적용하여 연구하였다. Dihydropyrimidinones를 one-pot 합성하는 반응에서, $H_3PMo_{12}O_{40}$ 촉매 보다[Cu(2,2'-bipy)]$[Cu(2,2'-bipy)_2]_2[PMo_8V_6O_{42}]{\cdot}1.5H_2O$ 촉매가 더 좋은 결과를 나타내었다.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.373-379
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• 2018

A transparent, freestanding Porous Aromatic Framework-97 (PAF-97) membrane was successfully synthesized via a one-step acid-catalyzed reaction. Due to the introduction of ether groups, the obtained PAF-97 membrane possesses enhanced structural flexibility, thus increasing the flexibility of the resulting membrane. This is proofed by the fact that the feeding pressure of the membrane reaches as high as 5.5 bar during the separation of gas mixtures. The Young's moduli of the membrane were 6.615 GPa and 11.11 GPa, either in a dry or hydrated state respectively. To be highlighted, under a feeding pressure of 3.6 bar, the PAF-97 membrane rendered the permeance values of $2.90{\times}10^{-7}$, $1.29{\times}10^{-8}mol\;m^{-2}s^{-1}Pa^{-1}$ for $CO_2$ and $CH_4$, respectively, with a $CO_2/CH_4$ permselectivity of 22.48.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3749-3754
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• 2013

Two 3D isomorphous and isostructural complexes, namely, $[Zn(BDOA)(bpy)(H_2O)_2]_n$ (1) and $[Cd(BDOA)-(bpy)(H_2O)_2]_n$ (2); (BDOA = Benzene-1,4-dioxyacetic acid, bpy = 4,4'-bipyridine) were synthesized under hydrothermal conditions and characterized by means of elemental analyses, thermogravimetric (TG), infrared spectrometry, and single crystal X-ray diffraction. Complexes 1 and 2 crystallize in the triclinic system, space group P-1 and each metal ion in the complexes are six-coordinated with the same coordination environment. In the as-synthesized complexes, $BDOA^{2-}$ anions link central metal ions to form a 1D zigzag chain $[-BDOA^{2-}-Zn(Cd)-BDOA^{2-}-Zn(Cd)-]_{\infty}$, whereas bpy pillars connect metal ions to generate a 1D linear chain $[-bpy-Zn(Cd)-bpy-Zn(Cd)-]_{\infty}$. Both infinite chains are interweaved into 2D grid-like layers which are further constructed into a 3D open framework, where hydrogen bonds play as the bridges between the adjacent 2D layers. Luminescent properties of complex 1 showed selectivity for $Hg^{2+}$ ion.

• 공업화학
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• 제35권3호
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• pp.255-259
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• 2024

본 연구에서는 음극 활물질로 폴리옥소메탈레이트(polyoxometalate, POM)인 규소텅스텐산(tungstosilic acid, TSA)과 양극 활물질로 염화 철(iron chloride)을 사용하고, 지지 전해질 황산(H₂SO₄) 수용액을 이용한 수계 레독스 흐름 전지(redox flow battery, RFB)를 구성하였다. 운전 결과에 따르면 용량 저하와 낮은 에너지 효율을 보이는 문제점이 있었다. 이와 같은 문제를 해결하기 위해서 양극 활물질에 유기화합물 첨가제인 말산(malic acid)를 첨가하여, 첨가제에 따른 전기화학적 특성과 셀 충방전 테스트를 진행하였다. 말산은 염화 철 수용액에서 킬레이트제로 작용하였으며, 말산내 두 개의 카르복실기가 철 이온과 효과적으로 배위결합을 형성한다. 이는, 양극 활물질인 염화 철의 전해질 저항을 줄어들게 하여 화학적으로 안정화되어 용량과 에너지 효율의 증가를 이끌어냈다.

• 전기화학회지
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• 제12권1호
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• pp.75-80
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• 2009

The effect of polyoxometalate monolayers on the electrodeposition of Au nanoparticles (AuNPs) on glassy carbon (GC) surfaces was examined by electrochemical and scanning electron microscope techniques. The presence of $SiMo_{12}O^{4-}_{40}$-layers resulted in average particle sizes of ca. 60 nm, which is larger than AuNPs deposited on bare GC surfaces. AuNPs electrodeposited on $SiMo_{12}O^{4-}_{40}$-modified GC surfaces for 20 s exhibited the best electrocatalytic activity for oxygen reduction. This system exhibited similar or slightly better efficiency for oxygen reduction than a bare Au electrode. Rotating disk electrode experiments were also performed and revealed that the catalytic reduction of oxygen on AuNPs deposited on $SiMo_{12}O^{4-}_{40}$-modified GC electrodes is a two-electron process.

• 펄프종이기술
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• 제37권5호통권113호
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• pp.56-62
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• 2005

The catalytic effect of molybdovandophosphate heteropolyanion (HPAs) on the delignification of kraft bagasse pulp by hydrogen peroxide has been investigated. Very small amounts of the catalyst (0.05 0.3 mM/l) gave convenient results. Partial reduction of the catalyst was also studied. The effect of reaction medium (water, ethyl alcohol and acetone) on the bleaching was also studied. The results obtained show that the optimum condition for bleaching in presence of polyoxometalate were 0.05 mM/l catalyst concentration at $70^{\circ}C$ reaction temperature and $7\%$ consistency at pH 2 in aqueous medium. The ratio of water to solvent of 60:40 from acetone gives higher brightness than ethyl alcohol. The catalyst solution can be reused for 5 times without any reduction in brightness. ESR for the blank and exhausted solutions under different conditions was also carried out to find the relation between reduced metals and pulp brightness.

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.3139-3141
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• 2012

• 공업화학
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• 제34권2호
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• pp.175-179
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• 2023

본 연구에서는 음극 활물질로 폴리옥소메탈에이트(polyoxometalate, POM)인 포스포몰리브 산(phosphomolybdic acid)와 양극 활물질로 페로시아나이드(ferrocyanide)를 지지 전해질인 수산화나트륨 수용액을 이용하여 산화환원 흐름 전지(redox flow battery, RFB)를 구성하였다. 다양한 농도의 수산화나트륨 수용액(1.0 M, 1.2 M, 1.4 M, 1.5 M, 1.6 M)을 이용하여 배터리의 성능테스트를 진행하였으며, 각 물질에 대한 전기화학적 특성과 안정성에 대해 연구하였다. 지지 전해질의 농도는 음극 활물질인 포스포몰리브 산에 영향을 주며 최적 값이 존재하고 농도가 증가할수록 전해질 저항이 줄어들게 되며 1.5 M에서 가장 줄어드는 현상을 확인하였고 1.6 M로 농도가 증가할 시 전해질 저항이 다시 증가한다는 것을 확인하였다. 전해질 저항의 감소는 전체 에너지 효율에도 영향을 주어 농도가 증가됨에 따라 효율은 증가하며 1.5 M에서 가장 좋은 배터리 성능을 보인다는 것을 확인하였다.