• 공업화학
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• 제31권3호
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• pp.258-266
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• 2020

CO₂로부터 5원환 탄산염의 합성은 지구 온난화를 문제를 해결하고 정밀한 화학 물질을 생산하는 유망한 방법 중 하나이다. 본 총설에서는 CO₂와 에폭시 화합물로부터 5원환 탄산염 합성을 위한 다공성 결정 물질인 metal-organic framework (MOF)의 촉매로써 적용 가능성에 대해 검토하였다. CO₂와 에폭시 화합물의 부가 반응에 대하여 MOF의 구조적 기능과 그에 따른 불균일계 촉매로써의 활성을 조사하였다. 그 결과, 5원환 탄산염 합성에서 MOF 촉매의 산점(acidic site)과 친핵체(nucleophile)의 상승효과(synergistic effect)에 의하여 반응성이 높아지는 것을 확인하였다. 또한 CO₂의 부가반응에서 설계된 MOF의 구조에 대한 영향과 반응메커니즘을 조사하여 제시하였다.

• Carbon letters
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• 제4권1호
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• pp.1-9
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• 2003

Recently, the control of pore-characteristics of nano-porous materials has been studied extensively because of their unique applications, which includes size-selective separation, gas adsorption/storage, heterogeneous catalysis, etc. The most widely adopted techniques for controlling pore characteristics include the utilization of pillar effect by metal oxide and of templates such as zeolites. More recently, coordination polymers constructed by transition metal ions and bridging organic ligands have afforded new types of nano-porous materials, porous metal-organic framework(porous MOF), with high degree and uniformity of porosity. The pore characteristics of these porous MOFs can be designed by controlling the coordination number and geometry of selected metal, e.g transition metal and rare-earth metal, and the size, rigidity, and coordination site of ligand. The synthesis of porous MOF by the assembly of metal ions with di-, tri-, and poly-topic N-bound organic linkers such as 4,4'-bipyridine(BPY) or multidentate linkers such as carboxylates, which allow for the formation of more rigid frameworks due to their ability to aggregate metal ions into M-O-C cluster, have been reported. Other porous MOF from co-ligand system or the ligand with both C-O and C-N type linkage can afford to control the shape and size of pores. Furthermore, for the rigidity and thermal stability of porous MOF, ring-type ligand such as porphyrin derivatives and ligands with ability of secondary bonding such as hydrogen and ionic bonding have been studied.

• 소성∙가공
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• 제33권4호
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• pp.261-269
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• 2024

This study aimed to optimize the MIL-53 metal-organic framework coatings for enhanced durability in carbon dioxide capture applications. We synthesized MIL-53 powders using a hydrothermal method and deposited them on stainless-steel substrates by spin coating at various speeds, ranging from 300 to 2,000 rpm. The microstructure, surface properties, and tribological characteristics of the coatings were analyzed systematically. The results indicated that the spin speed significantly impacted the coating uniformity and defect formation. Coatings prepared at moderate speeds of 500 to 1,000 rpm exhibited optimal thickness and density, resulting in superior wear resistance. The tribological tests revealed that the coatings prepared at 700 to 1000 rpm had the lowest wear rates. These findings offer valuable insights for the development of durable MOF-based coatings for carbon dioxide capture and other applications requiring long-term stability under mechanical stress.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1879-1882
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• 2014

• Bulletin of the Korean Chemical Society
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• 제27권10호
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• pp.1523-1524
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• 2006

• 센서학회지
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• 제26권6호
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• pp.379-385
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• 2017

In this study, an amperometric non-enzymatic glucose sensor was developed on the surface of a glassy carbon electrode by simply drop-casting the synthesized homogeneous suspension of hexagonal boron nitride (h-BN) nanosheets with a copper metal-organic framework (Cu-MOF) composite. Comprehensive analytical methods, including field-emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), cyclic voltammetry, electrochemical impedance spectroscopy, and amperometry, were used to investigate the surface and electrochemical characteristics of the h-BN-Cu-MOF composite. The FE-SEM, FT-IR, and XRD results showed that the h-BN-Cu-MOF composite was formed successfully and exhibited a good porous structure. The electrochemical results showed a sensor sensitivity of $18.1{\mu}A{\mu}M^{-1}cm^{-2}$ with a dynamic linearity range of $10-900{\mu}M$ glucose and a detection limit of $5.5{\mu}M$ glucose with a rapid turnaround time (less than 2 min). Additionally, the developed sensor exhibited satisfactory anti-interference ability against dopamine, ascorbic acid, uric acid, urea, and nitrate, and thus, can be applied to the design and development of non-enzymatic glucose sensors.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.160.1-160.1
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• 2014

Using a density functional theory calculation including van der Waals (vdW) corrections, we report that $H_2$ adsorption in a cubic-crystalline microporous metal-organic framework (MOF-5) leads to volume shrinkage, which is in contrast to the intuition that gas adsorption in a confined system (e.g., pores in a material) increases the internal pressure and then leads to volumetric expansion. This extraordinary phenomenon is closely related to the vdW interactions between MOF and $H_2$ along with the $H_2$-$H_2$ interaction, rather than the Madelung-type electrostatic interaction. At low temperatures, $H_2$ molecules adsorbed in the MOF-5 form highly symmetrical interlinked nanocages that change from a cube-like shape to a sphere-like shape with $H_2$ loading, helping to exert centrosymmetric forces and hydrostatic (volumetric) stresses from the collection of dispersive interactions. The generated internal negative stress is sufficient to overcome the stiffness of the MOF-5 which is a soft material with a low bulk modulus (15.54 GPa).

• 한국분말재료학회지
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• 제27권6호
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• pp.477-483
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• 2020

Metal-organic frameworks (MOFs) are of significant interest because of their high porosity, which facilitates their utilization in gas storage and catalysis. To enhance their current properties in these applications, it is necessary to elucidate the interactions between molecules in a confined environment that differ from those in bulk conditions. Herein, we study the confined molecular interaction by investigating the solvent-dependent photophysical properties of two different-sized molecules inside MOF-5. Ruthenium tris-bipyridine (Rubpy) and coumarin 153 (C153) are encapsulated in MOF-5. Rubpy with MOF-5 (Rubpy@MOF) is prepared by building MOF-5 around it, resulting in limited space for solvent molecules in the pores. The smaller C153 is encapsulated in the preformed MOF-5 (C153@MOF) by simply soaking the MOF in a concentrated C153 solution. C153@MOF permits more space for solvent molecules in the pore. Their characteristic absorption and emission spectra are examined to elucidate the confined molecular interactions. Rubpy@MOF and C153@MOF exhibit different spectral shifts compared to the guest molecules under bulk conditions. This discrepancy is attributed to the different micro-environments inside the pores, derived from confined host-guest interactions in the interplay of solvent molecules.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3213-3218
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• 2014

A metal organic framework-supported Nickel nanoparticle (Ni-MOF-5) was successfully synthesized using a simple impregnation method. The obtained solid acid catalyst was characterized by Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen adsorption-desorption and thermogravimetric analysis (TGA). The catalyst was highly crystalline with good thermodynamic stability (up to $400^{\circ}C$) and high surface area ($699m^2g^{-1}$). The catalyst was studied for the oxidation of ethyl benzene, and the results were monitored via gas chromatography (GC) and found that the Ni-MOF-5 catalyst was highly effective for ethyl benzene oxidation. The conversion of ethyl benzene and the selectivity for acetophenone were 55.3% and 90.2%, respectively.

• Bulletin of the Korean Chemical Society
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• 제30권12호
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• pp.2921-2926
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• 2009

Cu-BTC[$Cu_3(BTC)_2(H_2O)_3$, BTC = 1,3,5-benzenetricarboxylate], one of the most well-known metal-organic framework materials (MOF), has been synthesized under atmospheric pressure and room temperature by using ultrasound. The Cu-BTC can be obtained in 1 min in the presence of DMF (N,N-dimethylformamide), suggesting the possibility of continuous production of Cu-BTC. Moreover, the surface area and pore volume show that the concentration of DMF is important for the synthesis of Cu-BTC having high porosity. The morphology and phase also depend on the concentration of DMF : Cu-BTC cannot be obtained at room temperature in the absence of DMF and aggregated Cu-BTC (with low surface area) is produced in the presence of high concentration of DMF. It seems that the deprotonation of benzenetricarboxylic acid by base (such as DMF) is inevitable for the room temperature syntheses.