• 공업화학
• /
• 제33권5호
• /
• pp.523-531
• /
• 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.

• Korean Chemical Engineering Research
• /
• 제57권4호
• /
• pp.484-491
• /
• 2019

산업적으로 중요한 가치를 지니는 폴리프로필렌 합성의 원료인 프로필렌을 고순도로 얻기 위해서는 효율적인 프로필렌/프로판 분리 기술이 필요하다. 기존 증류 공정은 프로필렌과 프로판의 유사한 물리화학적 성질로 인해 매우 높은 에너지가 소모되기때문에, 흡착분리 기술이큰관심을받고있다. 본연구에서는 Grand Canonical Monte Carlo (GCMC) 분자 모사를 활용하여 기공의 형태가 다른 두 종류의 유무기복합다공체(Metal-Organic Frameworks)의 빈금속배위자리(open metal sites) 흡착 강도를 임의로 조절하며 프로필렌/프로판 흡착 분리 성능의 변화를 조사하였다. 흡착 분리 성능은 작업 용량, 선택도, Adsorption Figure of Merit (AFM) 등으로 평가하였고, 이를 통해 흡착제가 최적의 프로필렌/프로판 분리 성능을 가지기 위해 필요한 흡착 사이트의 밀도 및 강도 그리고 온도 조건 등을 제시하였다.

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

• 센서학회지
• /
• 제29권6호
• /
• pp.374-381
• /
• 2020

Hydrogen gas has attracted considerable attention as a promising candidate for future energy resources because of its eco-friendly characteristics; however, its highly combustible characteristics should be thoroughly examined to preclude potential disasters. In this regard, a highly sensitive method for the selective detection of H₂ is extremely important. To achieve excellent H₂ selectivity, the utilization of a metal-organic framework (MOF) membrane can physically screen interfering gas molecules by restricting the size of kinetic diameters that can penetrate its nanopores. This paper summarizes the various endeavors of researchers to utilize the MOF molecular sieving layer for the development of highly selective H₂ sensors. Further, the review affords useful insights into the development of highly reliable H₂ sensors.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2006년도 춘계학술대회
• /
• pp.9-12
• /
• 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.

• 멤브레인
• /
• 제34권1호
• /
• pp.30-37
• /
• 2024

전 세계적인 물 부족을 해결하기 위한 유망한 방법으로 수착제를 이용하여 공기 중에서 물을 수확하는 기술은 수자원이 부족한 지역에서 식수를 전달할 수 있는 큰 잠재력을 보여주고 있음. 본 총설에서는 대기 중 물을 수확하기 위한 수착제로 금속유기골격구조(MOF)를 사용하는 최근 연구에 대해 소개함. 제올라이트나 실리카 기반 물질과 같은 다른 수착제 물질에 비해, MOF는 상대습도 10% 부근에서 물 수착 곡선의 변곡점을 보이는 특성 덕분에 건조한 사막지역에서 물을 수확하기에 적합한 특성을 가지고 있음. 이러한 특성으로 말미암아 최근 MOF를 이용하여 물을 수확할 수 있는 실용적인 물 수확 장치를 개발하기 위한 연구가 활발히 진행되고 있음. 이 기술은 전 세계 어느 곳에서나 지리 환경적 영향을 받지 않고 대기 중의 물에 접근할 수 있기 때문에, 미래 지속가능한 수자원 확보 기술 측면에서 새로운 패러다임을 제시할 것으로 기대됨.

• Bulletin of the Korean Chemical Society
• /
• 제34권8호
• /
• pp.2375-2380
• /
• 2013

Two metal-organic frameworks based on the connectivity co-effect between rigid benzenedicarboxylic acid and bridging ligand have been synthesized $[Zn_2(3-NO_2-bdc)_2(4,4'-bpy)_2H_2O]_n$ (1), $[Co(3-NO_2-bdc)(4,4'-bpy)H_2O]_n$ (2) (where $3-NO_2-bdcH_2$ = 3-nitro-1,2-benzenedicarboxylic acid, 4,4'-bpy = 4,4'-bipyridine). The two novel complexes were characterized by IR spectrum, elemental analysis, fluorescent properties, thermogravimetric analysis, single-crystal X-ray diffraction and powder X-ray diffraction (PXRD). X-ray structure analysis reveals that 1 and 2 are two-dimensional (2D) network structures. Complex 1 and complex 2 belong to triclinic crystal with P-1 space group. The luminescence measurements reveal that two complexes exhibit good fluorescent emissions in the solid state at room temperature. Also, thermal decomposition process and powder X-ray diffraction of complexes were investigated.

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

• 한국세라믹학회지
• /
• 제53권2호
• /
• pp.200-205
• /
• 2016

With high specific surface area and pore structural diversity, MOFs show important applications in gas storage, catalysis, sensing, separation, and biomedicine. However, the stability of the structure of MOFs has restricted their application and development. In this study, zirconium metal organic frameworks with 9,10-dicarboxylic acid anthracene as ligand, named UIO-66 ($H_2DCA$), were synthesized and their properties and structures were characterized by XRD, SEM, and $N_2$ adsorption. We focus on the stability of the structure of UIO-66 ($H_2DCA$) under different conditions (acid, alkali, and water). The structural changes or ruins of UIO-66 ($H_2DCA$) were traced by means of XRD, TG, and FT-IR under different conditions. The results show that the UIO-66 ($H_2DCA$) materials are stable at 583 K, and that this structural stability is greatly influenced by different types of acid and alkali compounds. Importantly, we found that the structures maintain their stability in environments of nitric acid, triethylamine, and boiling water.

• 한국재료학회지
• /
• 제28권9호
• /
• pp.506-510
• /
• 2018

Nitrogen is a serious contaminant in natural gas because it decreases the energy density. The natural gas specification in South Korea requires a $N_2$ content of less than 1 mol%. Thus, cost-effective $N_2$ removal technology from natural gas is necessary, but until now the only option has been energy-intensive processes, e.g., cryogenic distillation. Using porous materials for the removal process would be beneficial for an efficient separation of $CH_4/N_2$ mixtures, but this still remains one of the challenges in modern separation technology due to the very similar size of the components. Among various porous materials, metal-organic frameworks (MOFs) present a promising candidate for the potential $CH_4/N_2$ separation material due to their unique structural flexibility. A MIL-53(Al), the most well-known flexible metal-organic framework, creates dynamic changes with closed pore (cp) transitions to open pores (ops), also called the 'breathing' phenomenon. We demonstrate the separation performance of $CH_4/N_2$ mixtures of MIL-53(Al) and its derivative $MIL-53-NH_2$. The $CH_4/N_2$ selectivity of $MIL-53-NH_2$ is higher than pristine MIL-53(Al), suggesting a stronger $CH_4$ interaction with $NH_2$.