• Journal of the Korean Electrochemical Society
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• v.8 no.2
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• pp.77-81
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• 2005

Porous-composite electrodes have been developed using silica gel, which reduce carbon aerogel usage with high cost. Silica gel powder was added to the carbon aerogel to simplify the manufacturing procedure and to increase the wet-ability, the mechanical strength and the CDI efficiency. Porous composite electrodes composed of carbon aerogel and silica gel powder were prepared by paste rolling method. Carbon aerosol composite electrodes with $10\times10cm^2$ are placed face to face between spacers, and assembled the four-stage series cells for CDI process. Each stage is composed of 45 cells. Four-stage series cells (flow through cells) for CDI process are put in continuous-system reactor containing 1,000ml-NaCl solution bath of 1,000 ppm. The four-stage series cells with carbon aerogel electrodes are charged at 1.2V and are discharged at 0.001V, and then read the current. Conclusively, removal efficiencies of ions using the four-stage series cells composed of carbon aerogel composite electrodes show good removal efficiency of $99\%$ respectively.

• Proceedings of the Materials Research Society of Korea Conference
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• 1995.11a
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• pp.127-127
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• 1995

• Journal of the Microelectronics and Packaging Society
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• v.24 no.3
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• pp.13-18
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• 2017

Water glass is much cheaper than silicon alkoxide, so it has advantage for commercialization. A condensation by acid catalyst makes considerable effect about the properties of water glass based silica aerogel among many factors in silica aerogel process. The pore structural properties of water glass based silica aerogel such as specific surface area and pore size distribution have been investigated through the changes in the amount and the kinds of acid catalyst. It has been confirmed that water glass based silica aerogel is affected by various conditions of catalyst in the condensation reaction such as the kind, concentration, and the amount of mole of acid catalyst on the properties of final products. Especially, it is checked that the effect of mole of acid is more prominent than that of concentration. In the case for conventional method with introducing 4M HCl in condensation step, the silica aerogel could be synthesized which has $394m^2/g$ of specific surface area, 2.20 cc/g of pore volume, 22.3 nm of average pore size, and 92.53% of porosity. On the other hand, when 4M sulfuric acid was used with 73 mmol at the condensation step of water glass based silica aerogel, the pore structural characteristics of water based silica aerogel showed better properties than the case of using HCl, for example, specific surface area was measured as $516m^2/g$, and pore volume, average pore diameter, and porosity were obtained as 3.10 cc/g, 24.1 nm, and 96.1%, respectively.

• Carbon letters
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• v.28
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• pp.16-23
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• 2018

A novel, unique, and effective method for carbon nanotube (CNT) dispersion by the free arc stimulation is proposed. CNTs are introduced as an aerogel into the air space via the dispersion method and can be utilized as a solution by adding it to solvents. The volume of the original generated CNT aerogel with a high-volume expansion ratio displays a performance two orders of magnitudes better than that of raw CNTs, which is considered a powerful characterization of the dispersion effect. The CNT aerogel, which was observed by scanning electron microscopy also showed a satisfactory dispersion morphology. Its structure and properties were tested before and after dispersion by Raman spectroscopy and great consistency was observed, which proved that the CNTs were undamaged. This approach may greatly promote the large-scale application of CNTs.

• Journal of the Korean Ceramic Society
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• v.47 no.6
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• pp.553-559
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• 2010

The synthesis behavior of nanoporous silica aerogel in the macroporous ceramic structure was observed using TEOS as a source material and glycerol as a DCCA(dry control chemical additive). Silica aerogel in the macroporous ceramic structure were synthesized through a sono-gel process. The wet gel in the macroporous ceramic structure were aged in ethanol for 72 h at $50^{\circ}C$. The aged wet gel was dried under supercritical drying condition. The addition of glycerol has a role of giving the uniform pore size distribution. The reproducibility of aerogel in the macroporous ceramic was improved in the glycerol(0.05 mol%) added to the silica sol and TEOS : $H_2O$=1 : 12.

• Journal of Powder Materials
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• v.18 no.3
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• pp.269-276
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• 2011

The synthesis behavior of nanoporous silica aerogel in the macroporous ceramic structure was observed using TEOS as a source material and glycerol as a dry control chemical additive (DCCA). Silica aerogel in the macroporous ceramic structure was synthesized via sono-gel process using hexamethyldiazane (HMDS) as a modification agent and n-hexane as a main solvent. The wet gel with a modified surface was dried at $105^{\circ}C$ under ambient pressure. The addition of glycerol appears to give the wet gel a more homogeneous microstructure. However, glycerol also retarded the rate of surface modification and solvent exchange. Silica aerogel completely filled the macroporous ceramic structure without defect in the condition of surface modification (20% HMDS/nhexane at 36hr).

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.491-495
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• 1999

$Ni_{0.2}V_2O_5$ aerogel (ARG) was synthesized via the sol gel method and has been studied with an emphasis on the characterization of its electrochemical properties. ARG appear to be amorphous layered material. Electron micrograph revealed that entangled fibrous textures has been grown to form anisotropic corrugated sheets. Several sites for the Li ion intercalation exist between the layers of ARG and average cell potential was 3.1 V vs $Li/Li^+$ Th charge transfer resistance increases 3 to 4 times as lithium composition increases, but the interphase resistance remains almost constant regardless of the lithium composition in thc ARG.

• Journal of the Korean Ceramic Society
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• v.32 no.3
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• pp.321-330
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• 1995

Homogeneous and monolithic TiO2-SiO2 binary aerogels were prepared by supercritical drying. Optical transparency was increased with adding acid catalyst during two step hydrolysis and with decreasing water content. These differences in optical transparency were related to microstructures of gel network formed through polycondensation reaction during supercritical drying process, rather than the final composition of aerogel.

• Journal of the Korean Ceramic Society
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• v.35 no.3
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• pp.264-272
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• 1998

The effect of catalytic condition on the properties of SiO2 aerogels has been investigated and then the dri-ed aerogels were partially densified to induce mechanical strength by heat treatment in order to prepare Type-VI silica by Sol-Gel method. Aerogel made by 1-step base process had the highest skeletal density lowest shrinkage and the smallest particle size. But in case of using acid catalyst in both 1st and 2nd step had the lowest skeletal density highest shrinkage and the largest particle size The aerogel synthesized by 1-step base process was most transparent because of its homogeneous microstructure. During heat treatments cracks occurred below 200$^{\circ}C$ for aerogel with the skeletal density lower than 1.9 g/cm3 but the with the higher skeletal density did not cracked up to 800$^{\circ}C$ shrinkage and skeletal density increased as heating temperature increased due to condensation and viscous sintering mechanism.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.9
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• pp.1318-1323
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• 2013

Thermal insulation material was prepared by cross-linking chemical reaction of silica aerogel and epoxy resin, which has a high porous and vacant properties. The structural, mechanical, and thermal properties were analyzed in order to verify its application for industrial and electrical applications. The thermal conductivities were changed from 115 mW/mK to 75 mW/mK by reducing the contents of nano-porous silica areogel powders. The compressive loading is also decreased by increasing the contents of silica aerogels by 20 wt% in aerogel/epoxy composites. It is concluded that the formulated composite materials can be applied to building materials, electronics parts, and heavy industries.