• Journal of Powder Materials
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• v.27 no.6
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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.

• Membrane Journal
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• v.25 no.6
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• pp.465-477
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• 2015

Recently membrane-based gas separation has attracted a lot of attention due to the growing demands on energy efficient separation processes. Current membrane-based gas separation is dominant by polymer membranes and limited mostly to non-condensable gases rather than condensable gases such as hydrocarbon isomers due to the limitation s of polymer materials. Metal-organic framework (MOF) materials, consisting of metal ions and organic ligands, have received a tremendous attention as membrane materials due to high surface area, controllable pore structure, and functionality. In this review, we provide a recent development of MOF membrane preparation methods and their gas separation applications.

• Carbon letters
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• v.10 no.1
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• pp.19-22
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• 2009

In this work, the hydrogen storage behaviors of carbon nanotubes (CNTs)/metal-organic frameworks-5 (MOF-5) hybrid composites (CNTs/MOF-5) were studied. Hydrothermal synthesis of MOF-5 was conducted by conventional convection heating using 1-methyl-2-pyrrolidone (NMP) as a solvent. Morphological characteristics and average size of the CNTs/MOF-5 were also obtained using a scanning electron microscopy (SEM). The pore structure and specific surface area of the CNTs/MOF-5 were analyzed by N2/77 K adsorption isotherms. The capacity of hydrogen storage of the CNTs/MOF-5 was investigated at 298 K/100 bar. As a result, the CNTs/MOF-5 had crystalline structures which were formed by hybrid synthesis process. It was noted that the CNTs/MOF-5 can be potentially encouraging materials for hydrogen adsorption and storage applications at room temperature.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.45.2-45.2
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• 2011

Metal organic frameworks (MOF) have generated considerable interests as a potential candidate for hydrogen storage owing to their extremely high surface-to-volume ratio and low density. In this study, Pt nanoparticles of about 3 nm in size were introduced outside MOF-5 [$Zn_4O$(1,4-benzenedicarbocylate)3], which was then encapsulated with hydrophobic microporous carbon black (denoted CB@Pt/MOF-5) in order to enhance hydrogen uptake capacity without decreasing the specific surface area and hydrostability. To study the chemical composition, morphology, crystal information, and properties of the synthesized material, a variety of techniques is employed, including WXRD, XPS, ICP-AES, FE-SEM, HR-TEM, and N2 adsorption-desorption, confirming the formation of novel hybrid composite designated CB@Pt/MOF-5 with highly crystalline structure, large specific surface area and pore volume. In addition, $H_2$ storage capacity for resulting material was measured using magnetic suspension microbalance at 77 and 298 K under high-pressure condition, and the hydrostability was also tested by exposing the sample to 33% relative humidity at $23^{\circ}C$ and measuring XRD as a function of time.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.65-67
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• 2011

The moment-of-fluid (MOF) method is a new volume-tracking method that accurately treats evolving material interfaces. The MOF method uses moment data, namely the material volume fraction, as well as the centroid, for a more accurate representation of the material configuration, interfaces and concomitant volume advection. In this paper, unstructured mesh extension of the MOF method is to be presented. The MOF method is coupled with a stabilized finite element incompressible Navier-Stokes solver for two materials. The effectiveness of the MOF method is demonstrated with a free-surface dam-break problem.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.4
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• pp.510-520
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• 2014

Metal-Organic Frameworks(MOFs) are attracting attentions from various fields including chemistry, materials science, physics and medical science because of its exceptionally large pore volumes and surface areas which far exceed those of zeolites. The possibilities of applications of MOFs for gas separation, catalysts, drug delivery, and high explosives detections have already been verified. In these review the author describes the structures, synthetic methods and applications of MOFs based on the literatures published during last 15 years to give the readers general pictures of MOF itself as well as the global research trends of these materials.

• Prospectives of Industrial Chemistry
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• v.23 no.3
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• pp.1-16
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• 2020

식품 산업에서 제품의 품질을 향상시키기 위해서는 약한 세기의 맛에서도 다양한 종류의 맛을 감지해낼 수 있어야만 한다. 이러한 목적 달성을 위해서 2차원 물질과 금속유기골격체(metal-organic framework, MOF)를 이용한 미각 감지 센서에 대한 연구들이 한창 진행 중이다. 2차원 물질 및 MOF는 고유한 특성으로 인하여 현재 다양한 분야에서 많은 관심을 받아오고 있으며 화학 및 생화학 감지 등 다양한 분야에서도 응용될 수 있다. 본 기고문에서는 미각 감지 응용에서 2차원 물질과 MOF의 최신 연구동향을 다루고자 한다. 본 기고문을 통하여 미각 감지 응용 분야에서 2차원 물질과 MOF의 작용 메커니즘을 이해하고 현재의 연구 현황 및 앞으로의 발전 방향을 알아보고자 한다.

• Applied Chemistry for Engineering
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• v.34 no.5
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• pp.556-565
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• 2023

Fast industrial and agricultural expansion result in the production of heavy metal ions (HMIs). These are exceedingly hazardous to both humans and the environment, and the necessity to eliminate them from aqueous systems prompts the development of novel materials. In the present study, a UIO-66 (COOH)₂ metal-organic framework (MOF) containing free carboxylic acid groups was post-synthetically modified with L-glutamic acid via the solid-solid reaction route. Pristine and glutamic acid-treated MOF materials were characterized in detail using several physicochemical techniques. Single-ion batch adsorption studies of Pb(II) and Hg(II) ions were carried out using pristine as well as amino acid-modified MOFs. We further examined parameters that influence removal efficiency, such as the initial concentration and contact time. The bare MOF had a higher ion adsorption capacity for Pb(II) (261.87 mg/g) than for Hg(II) ions (10.54 mg/g) at an initial concentration of 150 ppm. In contrast, an increased Hg(II) ion adsorption capacity was observed for the glutamic acid-modified MOF (80.6 mg/g) as compared to the bare MOF. The Hg(II) ion adsorption capacity increased by almost 87% after modification with glutamic acid. Fitting results of isotherm and kinetic data models indicated that the adsorption of Pb(II) on both pristine and glutamic acid-modified MOFs was due to surface complexation of Pb(II) ions with available -COOH groups (pyromellitic acid). Adsorption of Hg(II) on the glutamic acid-modified MOF was attributed to chelation, in which glutamic acid grafted onto the surface of the MOF formed chelates with Hg(II) ions.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.9-12
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• 2006

We performed molecular dynamics simulations on the conventional MOF, IRMOF-14 and the catenated MOF with two MOF chains, IRMOF13, to find out rational design and synthetic strategies toward efficient hydrogen storage materials. The molecular dynamics calculations were done using Universal force fields and the analysis of result was performed during the NVE dynamics after preliminary NVT dynamics at 77K. The results showed the density of adsorbed hydrogen molecules was increased in the various pores created by catenation of MOFs while the large amount of volume in conventional MOF was not effectively utilized to store hydrogen. Those calculation results commonly showed the proper control of pore si Be for hydrogen storage into MOF by catenation would be one of the efficient ways to increase hydrogen capacity of MOFs.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.402-407
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• 2022

Statistical design of experiments was used to optimize the MOF-5 synthesis process. A mixture design was employed to optimize precursor concentration. The optimal composition of three chemical materials, terephthalic acid, zinc acetate dihydrate, and N,N-dimethylformamide for MOF-5 synthesis was determined by extreme vertices design methods as follows; 1 mol : 2.7 mol : 40 mol. A multilevel factorial design was selected to screen the significance of synthesis reaction conditions such as temperature, time, and stirring speed. Statistical analysis results suggested excluding stirring speed from further investigation. Using a central composition design, the synthesis time and temperature were optimized. The quadratic model equation was derived from 13 synthesis experiments. The model predicted that MOF-5 synthesized at 119 ℃ for 10.4 h had the highest crystallinity.