• 정보학연구
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• 제10권2호
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• pp.37-45
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• 2007

The multiple-ability which the structure and the physical properties which the carbon or scull tube are unique show the applicability is superior in the plane indication element which is an indispensability of information communications apparatus, the stubbornness memory element, 2nd change of air and the rough copy dosage [khay] plaque seater, the hydrogen store material and the chemical sensor back and it has the possibility which will pass over the limit which the element of existing has. from the present paper it compared in the steel and only 10 the boat it did and it analyzed against an energy storage space voluntary application and developmental apply the carbon or scull tube trend in order about under researching the effective energy storage element it could be appeared, the technique of the strong carbon nano tube. 1. The hazard which embodies the energy storage element which uses the carbon or scull tube it follows in the function which stands and CNT of the structure which is various is necessary. 2. CNT fabrications of each one must precede possible not only must be each Cabinet conference circumstances quality gain and loss. 3. The structural control of syntheses, length controls, diameter controls and the metal - CNT junction control backs of quality CNT must precede. Applies the hereafter carbon or the scull tube in the various element with the primary preceding base technique for the structural plan technique of the carbon or scull tube to be certainly established, it does, secondarily the various element functional control technique which uses the carbon or scull tube is researched and will do.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.765-768
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• 2009

In this work, we prepared the activated multi-walled carbon nanotubes (Acti-MWNTs) with well developed physical surface structures, high specific surface area, and higher adsorption capacity by a physical activation process, in order to enhance the hydrogen storage capacity. The Acti-MWNTs' changes in the crystalline phase and in their lattice distortions were characterized by X-ray diffraction (XRD). The textural properties of the Acti-MWNTs were investigated by a nitrogen adsorption isotherms by Brunauer-Emmett-Teller (BET) equation and Harvath-Kawazoe (H-K) calculation, respectively. The hydrogen storage capacity of the Acti-MWNTs was investigated by BEL-HP at 298 K/100 bar. The hydrogen storage capacity of the Acti-MWNTs was improved with the physical activation, resulted from the formation of new hydrogen-favorable sites on the Acti-MWNT surfaces. In conclusion, the physical activation was one of the effective method to enhance the hydrogen storage capacity of the MWNTs.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.120-120
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• 2011

Graphene is a carbon based material and it has great potential of being utilized in various fields such as electronics, optics, and mechanics. In order to develop graphene-based logic systems, graphene field-effect transistor (GFET) has been extensively explored. GFET requires supporting devices, such as volatile memory, to function in an embedded logic system. As far as we understand, graphene has not been studied for volatile memory application, although several graphene non-volatile memories (GNVMs) have been reported. However, we think that these GNVM are unable to serve the logic system properly due to the very slow program/read speed. In this study, a GVM based on the GFET structure and using an engineered graphene channel is proposed. By manipulating the deposition condition, charge traps are introduced to graphene channel, which store charges temporarily, so as to enable volatile data storage for GFET. The proposed GVM shows satisfying performance in fast program/erase (P/E) and read speed. Moreover, this GVM has good compatibility with GFET in device fabrication process. This GVM can be designed to be dynamic random access memory (DRAM) in serving the logic systems application. We demonstrated GVM with the structure of FET. By manipulating the graphene synthesis process, we could engineer the charge trap density of graphene layer. In the range that our measurement system can support, we achieved a high performance of GVM in refresh (>10 ${\mu}s$) and retention time (~100 s). Because of high speed, when compared with other graphene based memory devices, GVM proposed in this study can be a strong contender for future electrical system applications.

• 한국재료학회지
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• 제21권6호
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• pp.327-333
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• 2011

Nanostructured cobalt materials have recently attracted considerable attention due to their potential applications in high-density data storage, magnetic separation and heterogeneous catalysts. The size as well as the morphology at the nano scale strongly influences the physical and chemical properties of cobalt nano materials. In this study, cobalt nano particles synthesized by a a polyol process, which is a liquid-phase reduction method, were investigated. Cobalt hydroxide ($Co(OH)_2$), as an intermediate reaction product, was synthesized by the reaction between cobalt sulphate heptahydrate ($CoSO_4{\cdot}7H_2O$) used as a precursor and sodium hydroxide (NaOH) dissolved in DI water. As-synthesized $Co(OH)_2$ was washed and filtered several times with DI water, because intermediate reaction products had not only $Co(OH)_2$ but also sodium sulphate ($Na_2SO_4$), as an impurity. Then the cobalt powder was synthesized by diethylene glycol (DEG), as a reduction agent, with various temperatures and times. Polyvinylpyrrolidone (PVP), as a capping agent, was also added to control agglomeration and dispersion of the cobalt nano particles. The optimized synthesis condition was achieved at $220^{\circ}C$ for 4 hours with 0.6 of the PVP/$Co(OH)_2$ molar ratio. Consequently, it was confirmed that the synthesized nano sized cobalt particles had a face centered cubic (fcc) structure and with a size range of 100-200 nm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1576-1578
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• 2004

The alumina membrane with nano sized pore was prepared from aluminum by anodic oxidation to apply for storage equipment, gas sensor and stamper. The pore size and cell size of the pores are controlled by anodic oxidation voltage. The alumina thickness was controlled by etching process using 0.2M $H_3PO_4$. The thickness of alumina on Si wafer was very accurately controlled by anodic oxidation time. Nickel with nano-sized grain was electroplated on the Au layer on silicon wafer. The fabricated pores on alumina membrane was the thickness of $7{\sim}10{\mu}m$ with straight nano-sized pore of 307${\sim}$120nm. The alumina by the etching process shows smooth surface. The size of Ni grain was 130nm and 250nm for 10mA/$cm^2$and 20mA/$cm^2$of electroplating currents, respectively.

• 한국수소및신에너지학회논문집
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• 제17권1호
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• pp.39-46
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• 2006

Highly ordered Li dispersed nickel oxide nanotubes were prepared with anodic aluminum oxide (AAO) template for hydrogen storage. Electron microscope results showed that uniform length and diameter of nickel oxide nanotubes were obtained. The wall thickness and outer diameter of nickel oxide nanotubes are about 40 - 50 nm and 200 - 400 nm, respectively. It was observed that the diameter of nickel oxide nanotubes is bigger than the pore diameter of AAO template. Li dispersed nickel oxide were consisted of nanoflakes and had structures of nanotubes and nanorods. For increasing the hydrogen adsorption and desorption capacity, the Li dispersed nickel oxide nanotubes were fluorinated. The fluorinated Li dispersed nickel oxide nanotubes showed 1.65 wt% of the hydrogen adsorption capacities at 77 K under 47 atm.

• 세라미스트
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• 제22권3호
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• pp.316-327
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• 2019

Carbon nitride has drawn broad interdisciplinary attention in diverse fields such as catalyst, energy storage, gas adsorption, biomedical sensing and even imaging. Intensive studies on carbon dioxide (CO₂) capture using carbon nitride materials with various nanostructures have been reported since it is needed to actively remove CO₂ from the atmosphere against climate change. This is mainly due to its tunable structural features, excellent physicochemical properties, and basic surface functionalities based on the presence of a large number of -NH or -NH₂ groups so that the nanostructured carbon nitrides are considered as suitable materials for CO₂ capture for future utilization as well. In this review, we summarize and highlight the recent progress in synthesis strategies of carbon nitride nanomaterials. Their superior CO₂ adsorption capabilities are also discussed with the structural and textural features. An outlook on possible further advances in carbon nitride is also included.

• 한국수소및신에너지학회논문집
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• 제16권3호
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• pp.262-268
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• 2005

[ $Zn(BH_4)_2$ ](8.4 wt% theoretical hydrogen storage capacity powders have been successfully synthesized by mechanochemical reaction from mixtures of $ZnCl_2$ and $NaBH_4$ powders in a 1:2 molar ratio in different times. $$ZnCl_2+2NaBH_4{\rightarrow}Zn(BH_4)_2+2NaCl$$ (1) $Zn(BH_4)_2$ powders were characterized by X-ray diffractometry(XRD), and Furier Transform Infrared spectrometry(FT-IR). The thermal stabilities of $Zn(BH_4)_2$ powders were studied by Differential scanning calorimetry(DSC), Thermogravimetry analysis(TGA), and Mass spectrometry(MS). $Zn(BH_4)_2$ can be tested for hydrogen evolution without further purification. The reaction to yield hydrogen is irreversible, the other products being compounds of Zn, and borane. $Zn(BH_4)_2$ thermally decomposes to release borane and hydrogen gas between about 85 and 150$^{\circ}C$.

• International Journal of Safety
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• 제6권1호
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• pp.16-21
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• 2007

Carbon nanotubes hold much promise as future materials for safe storage of hydrogen. In this paper, hydrogen transport mechanisms in single-walled carbon nano-tubes (SWNTs) for various temperatures and chiral indices were studied using molecular dynamics simulation method. The SWNT models of zigzag (10,0), chiral (10,5) and armchair (10,10) with hydrogen molecules inside were simulated at temperatures ranging from 253K to 373K. Movements of hydrogen molecules ($H_2$) inside a SWNT were analyzed using mean-square displacements and velocity autocorrelation functions.

• Elastomers and Composites
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• 제48권1호
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• pp.18-23
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• 2013

용융상태에서 nylon 12 elastomer에 소량의 dicumyl peroxide (DCP) 와 triallyl cyanuate (TAC)를 첨가하여 nylon 12 elastomer를 부분적으로 가교시켰으며, 이에 따른 nylon 12 elastomer의 기계적, 동적기계적 그리고 유변학적 특성을 tensile test, DMA, small amplitude oscillating rheometer를 이용하여 각각 알아보았다. TAC의 함량이 증가함에 따라 인장탄성률과 영률은 증가하고, 파단신율은 감소하였다. DMA 측정결과, DCP로 부분적으로 가교시킨 nylon 12 elastomer의 PTMG상의 유리전이온도는 순수한 nylon 12 elstomer에 비해 증가하였고, storage modulus는 nylon 12상의 용융온도 이상에서도 거의 일정한 값을 나타내었다. 부분적으로 가교시킴에 따른 유변학적 특성의 변화는 TAC의 함량이 증가함에 따라 solid like behavior와 shear thinning behavior가 점점 뚜렷하게 나타남을 알 수 있었다. 이로부터 nylon 12 elastomer를 용융상태에서 부분적으로 가교시킴으로써 용융가공성을 저하시키지 않으면서, 기계적 물성은 효과적으로 향상시킬 수 있었으며, 특히, nylon 12 elastomer의 사용가능 온도범위를 증가시킬 수 있었다.