• 한국산업융합학회 논문집
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• 제9권1호
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• pp.87-91
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• 2006

This research exposes the process of carbonization of solid waste from the city and the method of activated, as well as the process of meso-porous under several test conditions. In addition, it is expected that the active carbon obtained through this process can be used as filter for air and sewage treatment, and can absorb dioxin(as almost 60-80% of meso-porous and porous properties area) unlike the existing active carbon.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 제17회 워크샵 및 추계학술대회
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• pp.662-662
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• 2005

• 공업화학
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• 제20권4호
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• pp.396-401
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• 2009

전기이중층 캐패시터의 성능향상을 위한 전극물질로서 resorcinol-formaldehyde수지를 탄소원으로 사용하여 meso-pore 비율 52~64%의 기공특성을 지니며 직경 $2{\sim}10{\mu}m$의 미세구형 활성탄을 제조하였다. 이 활성탄을 전기이중층에 적용한 결과, meso-pore구조의 미세구형활성탄은 전하전달저항의 저감 및 충방전율 수용능력 향상에 효과적인 영향을 나타내어 전기이중층 캐패시터의 성능향상을 위한 효과적인 전극물질이 될 수 있음을 확인할 수 있었다.

• Carbon letters
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• 제24권
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• pp.73-81
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• 2017

Interconnected meso/microporous activated carbons were prepared from pumpkin seeds using a simple chemical activation method. The porous carbon materials were prepared at different temperatures (PS-600, PS-700, PS-800, and PS-900) and demonstrated huge surface areas ($645-2029m^2g^{-1}$) with excellent pore volumes ($0.27-1.30cm^3g^{-1}$). The well-condensed graphitic structure of the prepared activated carbon materials was confirmed by Raman and X-ray diffraction analyses. The presence of heteroatoms (O and N) in the carbon materials was confirmed by X-ray photoemission spectroscopy. High resolution transmission electron microscopic images and selected area diffraction patters further revealed the porous structure and amorphous nature of the prepared electrode materials. The resultant porous carbons (PS-600, PS-700, PS-800, and PS-900) were utilized as electrode material for supercapacitors. To our delight, the PS-900 demonstrated a maximum specific capacitance (Cs) of $303F\;g^{-1}$ in 1.0 M $H_2SO_4 $ at a scan rate of 5 mV. The electrochemical impedance spectra confirmed the poor electrical resistance of the electrode materials. Moreover, the stability of the PS-900 was found to be excellent (no significant change in the Cs even after 6000 cycles).

• Journal of Electrochemical Science and Technology
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• 제12권2호
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• pp.204-211
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• 2021

We report, synthesis of high surface area composite carbon aerogel using additive based polymerization technique by incorporating graphitic porous carbon as additive. This additive was separately prepared using sol-gel polymerization of resorcinol-furfuraldehyde in iso-propyl alcohol medium at much above the routine gelation temperature to yield porous carbon (CA-IPA) having graphitic layered morphology. CA-IPA exhibited a unique combination of meso-pore dominated surface area (~ 700 m²/g) and good conductivity of ~ 300 S/m. The composite carbon aerogel (CCA) was synthesized by traditional aqueous medium based resorcinol-formaldehyde gelation with CA-IPA as additive. The presence of CA-IPA favored enhanced meso-porosity as well as contributed to improvement in bulk conductivity. Based on the surface area characteristics, CCA-8 composition having 8% additive was found to be optimum. It showed specific surface area of ~ 2056 m²/g, mesopore area of 827 m²/g and electrical conductivity of 180 S/m. The electrode formed with CCA-8 showed improved electrochemical behavior, with specific capacitance of 148 F/g & ESR < 1 Ω, making it a better choice as super capacitor for energy storage applications.

• 한국산학기술학회논문지
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• 제22권2호
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• pp.26-32
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• 2021

카본 전극 페로브스카이트 태양전지의 광활성층을 형성하는데 열판, 오븐, 쾌속열처리로 방법을 달리하며 이때 광전기적 특성과 미세구조 변화를 확인하였다. Glass/FTO/compact TiO2/meso TiO2/meso ZrO2/perovskite/carbon electrode 구조의 페로브스카이트 태양전지 소자를 열판 공정, 오븐 공정, RTA(rapid thermal annealing) 공정을 이용하여 준비하였다. 이때 광전기적 특성과 미세구조를 solar simulator와 광학현미경, 장발산주사전자현미경을 이용하여 각 소자의 특성을 분석하였다. 광전기적 특성 분석 결과, RTA 공정을 이용하여 제작한 소자에서 가장 우수한 광전기적 특성을 확인할 수 있었다. 미세구조 분석 결과 열판 공정과 오븐 공정으로 제작한 시편은 카본 전극 상부에 과잉 페로브스카이트 상이 형성되고, RTA 공정으로 제작한 시편에서는 시편 상부에 과잉 페로브스카이트 상 없이, 균일한 페로브스카이트가 형성된 것을 확인할 수 있었다. 또한 단면 미세구조에서는 RTA 공정으로 제작한 소자가 다공성 카본 전극 층에 고밀도의 페로브스카이트 층을 형성하여 우수한 광전기적 특성을 나타내었다. 따라서 대면적 소자 제작의 공정시간을 고려한 새로운 열처리방안으로 RTA 방법의 채용 가능성을 확인하였다.

• 대한화장품학회지
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• 제30권2호
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• pp.189-195
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• 2004

카본 블랙은 매우 낮은 밀도로 화장품에는 사용되지 않고 있지만 독성이 없고 안정한 물리적 특성과 검은색의 특성으로 이용 가치가 있다고 사료되는 바이다. 본 연구에서는 TEOS, a) PEO/ lecithin, b) PEO/polyethylene glycol, c) lecithin/polyethylene을 ethanol/water 수용액상에서 계면활성제를 탄화시켜 sol-gei반응에 의해 meso-porous silica샘플을 얻었고 N2 조건하 50$0^{\circ}C$에서 열처리된 organic-inorganic hybrid silica를 합성하였다. Pore안에 카본 블랙을 함유하는 meso-porous silica는 친수성, 소수성 용매에서 모두 좋은 분산성을 보여준다. 이 샘플은 BET에 의해 specific surface area (750$m^2$/g)과 pore size (4-6 nm)이고, XRD측정으로 pore structure (cylindrical type)를, 샘플의 SEM촬영으로 morphology(0.1-0.5$\mu\textrm{m}$ 입자 크기를 갖는 spherical powder)를 갖는다는 것을 알아냈다. 이렇게 합성한 카본-실리카 블랙 컬러를 마스카라에 적용하면 일반적으로 마스카라에 사용되던 블랙 컬러 사용시 보다 좀더 검은색을 보여주는 것은 물론이고 우수한 분산성도 갖는다. 무엇보다 이 파우더의 밀도 조절이 가능하여 마스카라 뿐 만 아니라 모든 화장품에의 사용이 가능하다.

• Structural Engineering and Mechanics
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• 제33권4호
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• pp.429-446
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• 2009

Three-scale homogenization procedure is proposed in this paper to provide estimates of the effective thermal conductivities of porous carbon-carbon textile composites. On each scale - the level of fiber tow (micro-scale), the level of yarns (meso-scale) and the level of laminate (macro-scale) - a two step homogenization procedure based on the Mori-Tanaka averaging scheme is adopted. This involves evaluation of the effective properties first in the absence of pores. In the next step, an ellipsoidal pore is introduced into a new, generally orthotropic, matrix to make provision for the presence of crimp voids and transverse and delamination cracks resulting from the thermal transformation of a polymeric precursor into the carbon matrix. Other sources of imperfections also attributed to the manufacturing processes, including non-uniform texture of the reinforcements, are taken into consideration through the histograms of inclination angles measured along the fiber tow path together with a particular shape of the equivalent ellipsoidal inclusion proposed already in Sko ek (1998). The analysis shows that a reasonable agreement of the numerical predictions with experimental measurements can be achieved.

• 한국재료학회지
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• 제31권3호
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• pp.115-121
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• 2021

MnO2 can be potentially utilized as an electrode material for redox capacitors. The deposition of MnO2 with poor electrical conductivity onto porous carbons supplies them with additional conductive paths; as a result, the capacitance of the electrical double layer formed on the porous carbon surface can be utilized together with the redox capacitance of MnO2. However, the obtained composites are not generally suitable for industrial production because they require the use of expensive porous carbons and/or inefficient fabrication methods. Thus, to develop an effective preparation procedure of the composite, a suitable structure of porous carbons must be determined. In this study, MnO2/C composites have been prepared from activated carbon gels with various pore sizes, and their electrical properties are investigated via cyclic voltammetry. In particular, mesoporous carbons with a pore size of around 20 nm form a composite with a relatively low capacitance (98 F/g-composite) and poor rate performance despite the moderate redox capacitance obtained for MnO2 (313 F/g-MnO2). On the other hand, using macro-porous carbons with a pore size of around 60 nm increases the MnO2 redox capacitance (399 F/g-MnO2) as well as the capacitance and rate performance of the entire material (203 F/g-composite). The obtained results can be used in the industrial manufacturing of MnO2/C composites for supercapacitor electrodes from the commercially available porous carbons.

• Carbon letters
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• 제28권
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• pp.116-120
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• 2018

Nitrogen-doped carbons have attracted much attention due to their novel application in relation to gas storage. In this study, nitrogen-doped porous carbons were synthesized using SBA-15 as a template, polypyrrole as the carbon and nitrogen precursor, and KOH as an activating agent. The effect of the activation temperature ($600-850^{\circ}C$) on the $CO_2$ adsorption capacity of the obtained porous carbons was studied. Characterization of the resulting carbons showed that they were micro-/meso-porous carbon materials with a well-developed pore structure that varied with the activation temperature. The highest surface area of $1488m^2g^{-1}$ was achieved at an activation temperature of $800^{\circ}C$ (AC-800). The nitrogen content of the activated carbon decreased from 4.74 to 1.39 wt% with an increase in the activation temperature from 600 to $850^{\circ}C$. This shows that nitrogen is oxidized and more easily removed than carbon during the activation process, which indicates that C-N bonds are more easily ruptured at higher temperatures. Furthermore, $CO_2$ adsorption isotherms showed that AC-800 exhibited the best $CO_2$ adsorption capacity of $110mg\;g^{-1}$ at 298 K and 1 bar.