• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.213-214
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• 2023

The burden of housing heating costs has increased as energy prices such as global oil prices (28.1%), LNG (38%) and minerals (100%) have soared due to the Ukraine crisis. Accordingly, an electrically conductive cement composites had developed using waste carbon materials such as waste cathode materials, waste CNTs, and waste carbon fibers, and the heat generation performance was evaluated.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2008년도 추계학술발표대회 및 제15회 신소재 심포지엄
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• pp.36.1-36.1
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• 2008

• 공업화학
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• 제28권3호
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• pp.299-305
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• 2017

활성탄소섬유가 전사선 조사에 의해 표면 개질되었고, NO가스 감지 능력에 미치는 영향을 살펴보기 위하여 이를 가스센서 전극으로 이용하였다. XPS 분석결과는 전자선에 의하여 표면처리된 활성탄소섬유의 산소 성분이 감소하였으며 표면의 $sp^2$ 결합탄소가 증가한 것을 보여주었다. 이러한 결과는 전자빔 조사에 따른 활성탄소섬유 표면의 구조적 변형때문으로 사료된다. 100 kGy의 전자빔이 조사된 활성탄소섬유 전극의 NO가스 민감도는 약 4%에서 약 8%로 크게 증가하였고, 그 감지 시간 또한 약 360 s에서 120 s로 의미 있게 향상되었다. 이러한 결과는 활성탄소섬유의 전자빔 조사에 의하여 $sp^2$ 탄소 결합의 증가때문에 기인한 것으로, 이는 NO가스 센싱에 대한 전극저항 변화에 상당히 영향을 주었다.

• Korean Chemical Engineering Research
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• 제57권5호
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• pp.606-610
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• 2019

본 연구에서 우리는 보론 도핑된 다이아몬드 나노물질을 이용하여 유연성 탄소 섬유 기반의 전극(CF-BDD 전극)을 개발하고, 이를 비효소적 글루코스 센서에 적용하여 전기화학적 특성을 확인하였다. 이 전극은 탄소 섬유 표면에 정전하 자기조립법을 이용하여 BDD 층을 증착하여 제작하였다. 이 전극 물질의 표면 구조는 주사전자 현미경(SEM)을 이용하여 분석하였으며, 전기화학적 특성 및 센싱 성능 분석은 시간대전류법(CA)와 순환전압 전류법(CV), 전기화학 임피던스(EIS)으로 실행하였다. 제작된 CF-BDD 전극은 산화-환원 화학종과 전극 계면 간의 effective direct electron transfer와 large effective surface area, high catalytic activity의 우수한 특성들을 보였다. 결과적으로, CF 센서와 비교에서 CF-BDD 센서는 더 넓은 선형 농도 범위(3.75~50 mM)와 더 빠른 감응 시간(3초 이내), 더 높은 감도(388.8 nA/mM) 등의 향상된 센싱 특성을 보였다. 따라서, 본 연구에서 개발된 전극 물질은 다양한 전기화학 센서 뿐 아니라, 웨어러블 센서 소재로도 활용 가능할 것으로 기대된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.1184-1187
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• 2003

Electrochemical capacitors are becoming attractive energy storage systems particularly for applications involving high power requirements such as hybrid systems consisting of batteries and electrochemical capacitors for electric vehicle propulsion. A new type electric double layer capacitor (EDLC) was constructed by using carbon nanofibers (CNFs) and DAAQ(1,5-diaminoanthraquinone) electrode. Carbonaceous materials are found in variety forms such as graphite, diamond, carbon fibers etc. While all the carbon nanofibers include impurities such as amorphous carbon, nanoparticles, catalytic metals and incompletely grown carbons. We have eliminated of Ni particles and some carbonaceous particles in nitric acid. Nitric acid treated CNFs could be covered with very thin DAAQ oligomer from the results of CV and TG analyses and SEM images. DAAQ oligomer film exhibited a specific capacity as 45-50 Ah/kg in 4M $H_2SO_4$. We established Process Parameters of the technique for the formation of nano-structured materials. Furthermore, improved the capacitive properties of the nano structured CNFs electrodes using controlled solution chemistry. As a result, CNFs coated by DAAQ composite electrode showed relatively good electrochemical behaviors in acidic electrolyte system with respect to specific capacity and scan rate dependency.

• 공업화학
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• 제29권2호
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• pp.191-195
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• 2018

본 실험에서는 활성탄소섬유의 미세기공구조가 신경작용제 유사가스인 dimethyl methylphosphonate (DMMP) 감응 특성에 미치는 영향을 고찰하였다. 탄소섬유에 화학적 활성화법을 이용하여 기공구조를 부여하였고, 이를 이용하여 가스센서용 전극을 제조하였다. N형 반도체인 polyacrylonitrile (PAN)계 활성탄소섬유 기반 전극은 환원성 가스인 DMMP로부터 전자를 받아 정공의 밀도 감소로 인하여 전기저항이 감소하게 되었다. DMMP 가스센서의 민감도는 미세기공 부피가 증가함에 따라 1.7%에서 5.1%까지 증가하였다. 이는 분자 크기가 0.57 nm인 DMMP를 흡착하기에 적합한 미세기공이 형성됨에 따라, DMMP와 활성탄소섬유간의 전자 이동이 용이해졌기 때문이라 사료된다. 결론적으로, 높은 감도의 DMMP 가스센서를 제조하기 위해서는 적절한 기공구조 조절이 중요한 역할을 한다고 판단된다.

• Composites Research
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• 제29권4호
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• pp.132-137
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• 2016

Based on mussel-inspired polydopamine (PDA), a novel technique to fabricate carbon nanowire (CNW) arrays is presented for a possible use of porous carbon electrode in electrochemical energy storage applications. PDA can give more porosity and nitrogen-doping effect to carbon electrodes, since it has high graphitic carbon yield characteristic and rich amine functionalities. Using such outstanding properties, the applicability of PDA for electrochemical energy storage devices was investigated. To achieve this, the decoration of the CNW arrays on carbon fiber surface was performed to increase the surface area for storage of electrical charge and the chemical active sites. Here, zinc oxide (ZnO) nanowire (NW) arrays were hydrothermally grown on the carbon fiber surface and then, PDA was coated on ZnO NWs. Finally, high temperature annealing was performed to carbonize PDA coating layers. For higher energy density, manganese oxide ($MnO_x$) nanoparticles (NPs), were deposited on the carbonized PDA NW arrays. The enlarged surface area induced by carbon nanowire arrays led to a 4.7-fold enhancement in areal capacitance compared to that of bare carbon fibers. The capacitance of nanowire-decorated electrodes reached up to $105.7mF/cm^2$, which is 59 times higher than that of pristine carbon fibers.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.1220-1223
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• 2003

A new type electric double layer capacitor (EDLC) was constructed by using carbon nanofibers (CNFs) and DAAQ(1,5-diaminoanthraquinone) electrode. Carbonaceous materials are found in variety forms such as graphite, diamond, carbon fibers etc. While all the carbon nanofibers include impurities such as amorphous carbon, nanoparticles, catalytic metals and incompletely grown carbons. We have eliminated of Ni particles and some carbonaceous particles in nitric acid. Nitric acid treated CNFs could be covered with very thin DAAQ oligomer from the results of CV and TG analyses and SEM images. A crystalline supramolecular oligomer of 1,5-diaminoanthraquinone(DAAQ) was successfully prepared as a thin film by electrochemical oxidation from an acidic non-aqueous medium. DAAQ oligomer film exhibited a specific capacity as 45-50 Ah/kg in 4M $H_2SO_4$. Its electrochemical characteristics were investigated by cyclic voltammetry. And compared with different electrolyte of aqueous type. During ultrasonic irradiation CNFs was to disperse in 0.1M $H_2SO_4$. As a result, CNFs coated by DAAQ composite electrode showed relatively good electrochemical behaviors.

• Carbon letters
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• 제12권1호
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• pp.21-25
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• 2011

A novel electrode for an NO gas sensor was fabricated from electrospun polyacrylonitrile fibers by thermal treatment to obtain carbon fibers followed by chemical activation to enhance the activity of gas adsorption sites. The activation process improved the porous structure, increasing the specific surface area and allowing for efficient gas adsorption. The gas sensing ability and response time were improved by the increased surface area and micropore fraction. High performance gas sensing was then demonstrated by following a proposed mechanism based on the activation effects. Initially, the pore structure developed by activation significantly increased the amount of adsorbed gas, as shown by the high sensitivity of the gas sensor. Additionally, the increased micropore fraction enabled a rapid sensor response time due to improve the adsorption speed. Overall, the sensitivity for NO gas was improved approximately six-fold, and the response time was reduced by approximately 83% due to the effects of chemical activation.

• Journal of Electrochemical Science and Technology
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• 제1권2호
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• pp.117-120
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• 2010

Materials used as fuel cell electrode should be light, high conductive, high surface area for reaction, catalytic surface and uniformity of porous structure. Nickel is widely used in electrode materials because it itself has catalytic properties. When used as electrode materials, nickel of only a few im on the surface may be sufficient to conduct the catalytic role. To manufacture the nickel with porous structure, Electroless nickel plating on carbon fiber be conducted. Because electroless nickel plating is possible to do uniform coating on the surface of substrate with complex shape. Acidic bath and alkaline bathe were used in electroless nickel plating bath, and pH and temperature of bath were controlled. The rate of electroless plating in alkaline bath was faster than that in acidic bath. As increasing pH and temperature, the rate of electrolee plating was increased. The content of phosphorous in nickel deposit was higher in acidic bath than that in alkaline bath. As a result, the uniform nickel deposit on porous carbon fiber was conducted.