• Title/Summary/Keyword: MOF

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The Fire Cause Analysis and Judgement of Metering Out Fit(MOF) Installed Outdoors (옥외에 설치한 계기용변성기의 화재원인 분석과 판정)

  • Shong, Kil-Mok;Kim, Young-Seog;Kim, Sun-Gu
    • Journal of Korean Institute of Fire Investigation
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    • v.11 no.1
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    • pp.75-90
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    • 2007
  • In this paper, we analyzed on the fire cause of the metering out fit(MOF) installed the outdoors in domestic. There are observed by the rule is approved officially such as KS C IEC. and developed into the judgement can be in site. As the results, there founded out the fire cause on the gasket parts of MOF as the process of work which finish is bad. It's estimated the fire process that water percolates through on the MOF according to the un-airtight gasket.

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금속-유기 구조체 기반 비효소식 글루코오스 센서

  • Kim, Gi-Jun;Bae, Yun-Sang;Kim, Hyeon-Jong
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2018.06a
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    • pp.92.2-92.2
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    • 2018
  • 빠르고 정확한 글루코오스 농도 측정은 의료, 식품, 환경 등 다양한 산업에서 매우 중요하다. 글루코오스 산화효소를 기반으로 하는 현재 글루코오스 센서는 높은 감도와 선택성을 갖지만 온도변화나 다른 화학물 등 환경에 취약하다는 단점이 있다. 따라서 최근 비효소식 글루코오스 센서에 대한 연구가 활발히 진행되고 있다. 금속-유기 구조체(MOFs)는 금속이온과 유기물 리간드로 구성된 결정성 다공체로, 큰 기공 크기와 비표면적, 안정성 등을 특징으로 갖는다. 대부분의 MOFs는 전기전도도가 낮지만 금속이온의 산화/환원, 리간드의 화학적 개질을 통해 전기화학분야에서도 다양하게 연구되고 있다. 본 연구에서는 글루코오스 농도 측정을 위한 전극촉매로 다양한 금속이온과 리간드로 이루어진 MOFs를 합성했다. 표면분석을 통해 MOFs의 전기화학적 처리 전후의 구조와 성질 변화를 관찰했고 전기화학적 분석을 통해 금속이온과 리간드의 종류가 감도, 선택성 등 글루코오스 검지 성능에 주는 영향을 분석했다. 그 결과 Ni, Co 기반의 MOFs가 글루코오스에 대해 높은 감도를 보였으며 이를 통해 MOFs의 글루코오스 센서로의 응용 가능성을 확인했다.

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Molecular Dynamics Simulation on Hydrogen Adsorption into Catenated Metal Organic Frameworks (분자 동역학을 이용한 상호 관통된 Metal Organic Framework의 수소 흡착에 관한 연구)

  • Lee, Tae-Bum;Kim, Dae-Jin;Jung, Dong-Hyun;Kim, Ja-Heon;Choi, Seung-Hoon
    • 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.

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Influence of Urea Precursor on the Electrochemical Properties of Ni-Co-based Metal Organic Framework Electrodes for Supercapacitors

  • Jung, Ye Seul;Jung, Yongju;Kim, Seok
    • Applied Chemistry for Engineering
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    • v.33 no.5
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    • pp.523-531
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    • 2022
  • A NiCo-metal organic framework (MOF) electrode, prepared using urea as a surfactant, was synthesized using a one-pot hydrothermal method. The addition of urea to the NiCo-MOF creates interstitial voids and an ultra-thin nanostructure in the NiCo-MOF, which improves its charge transfer performance. We obtained the optimal metal to surfactant ratio to achieve the best specific capacitance. The NiCo-MOF was employed as the working electrode material in a three-electrode system. Field emission scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy were employed to characterize the microstructures and morphologies of the composites. Cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy curves were employed to quantify the electrochemical properties of the electrodes in a 6 M KOH electrolyte.

Pt/MOF-5 Hybrid Composite Encapsulated with Microporous Carbon Black to Improve Hydrogen Storage Capacity and Hydrostability

  • Yeo, Sin-Yeong;Gwak, Seung-Yeop
    • 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.

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Guest Changes Host: Adsorption Site and Binding Nature of Hydrogen in MOF-5

  • Ju, Jae-Yong;Kim, Hyeong-Jun;Han, Sang-Su
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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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).

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Synthesis and studies on novel Copper adenine MOF for $CO_2$ adsorption (이산화탄소 흡착용 구리 아데닌 MOF 합성 및 연구)

  • Ganesh, Mani;Hemalatha, Pushparaj;Peng, Mei Mei;Kim, Dae-Kyung;Jang, Hyun-Tae
    • Proceedings of the KAIS Fall Conference
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    • 2011.12a
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    • pp.357-360
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    • 2011
  • A new copper adenine MOF (Bio-MOF) was synthesized by hydrothermal procedure and explored for its low temperature $CO_2$ adsorption. In this adenine a DNA nucleotide was used as a ligand for Cu in DMF solution at $130^{\circ}C$. The synthesized Bio MOF was characterized by XRD, SEM, EDS, TG and BE Tresults. The material possesses high surface area (716.08 $m^2g^{-1}$) with mono dispersed particles of about 2.126 nm. The maximum $CO_2$ adsorption capacity is 5wt% at $50^{\circ}C$, which is regenerable at $100^{\circ}C$ which is very low when compared to other metal organic frame work studied. This study proves that the synthesized material is also be a choice materials for low temperature $CO_2$adsorption.

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Synthesis and characterization of the two-fold interpenetrated Tb(III)-based metal-organic framework (이중 상호 침투 구조를 갖는 신규 터븀(III) 기반 금속-유기 골격체의 합성 및 특성연구)

  • Song, Jeong Hwa
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.32 no.6
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    • pp.225-230
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    • 2022
  • A new two-fold interpenetrating two-dimensional (2D) Tb(III) metal-organic framework (MOF), [Tb(p-XBP4)2.5(H2O)2]·W(CN)8 (1), was prepared using a p-XBP4 (N,N'-p-phenylenedimethylenbis(pyridin-4-one)), Cs3[W(CN)8], and Tb(NO3)3·6H2O. The single crystal X-ray diffraction indicated that Tb-MOF exhibits a unique two-fold interpenetrating 2-D framework. It was also characterized through Fourier transform infrared spectroscopy (FTIR), and single and powder X-ray diffraction. To probe the molecular magnetic behavior, the magnetic properties of Tb-MOF were investigated by direct-current (DC) and alternating-current (AC) magnetic susceptibilities measurements and discussed.

Glutamic Acid-Grafted Metal-Organic Framework: Preparation, Characterization, and Heavy Metal Ion Removal Studies

  • Phani Brahma Somayajulu Rallapalli;Jeong Hyub Ha
    • 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.

Effect of Growth and Nitrogen Use Efficiency to Chinese Cabbage under Fermented Organic Fertilizer Treatment with Domestic Resource (국내 자원으로 제조한 발효 유기질비료가 배추의 생육 및 질소이용효율에 미치는 영향)

  • You-Jin Kim;So-Hui Kim;Sang-Min Lee;Cho-Rong Lee
    • Journal of the Korea Organic Resources Recycling Association
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    • v.31 no.3
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    • pp.83-91
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    • 2023
  • This study investigate growth responses of Chinese cabbage and nitrogen use efficiency (NUE) to application of fermented organic fertilizer produced from domestic organic resources for developing alternative materials instead of imported castor oil meal. Two types of fermented fertilizers (Fermented Organic Fertilizer A (OFA) and Fermented Organic Fertilizer B (OFB)) were produced by mixing distillers dried grains 30%, sesame cake 30%, rice bran 20% and fish meal 20% under different fermentation conditions. Treatment consisted of OFA is fermented for 21 days on plastic greenhouse, OFB is fermented for 5 days on 40℃, and MOF (Mixed Organic Fertilizer) is a fertilizer made with castor bean as the main ingredient. OFA, OFB and MOF were applied at the rate of 320 kg N/ha. Chinese cabbages were cultivated from Aug. to Nov. in 2022. Growth and yield of Chinese cabbage were no significant differences among all treatments except control (non-fertilized, NF). However, NUE of Chinese cabbage was higher the fermented fertilizer treatment (OFB: 81.4%, OFA: 79.1%) than the MOF (65.3%). It was observed that urease activity in the fermented fertilizer treatment was significantly higher than the MOF. This result confirmed that fermented fertilizers have similar effect on growth and yield with the MOF and could improve the NUE of crop.