• Bulletin of the Korean Chemical Society
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• 제27권11호
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• pp.1763-1768
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• 2006

The application of poly(Co(II)-(1,8-diaminonaphthalene))(poly(Co-DAN)) and poly(1,8-diaminonaphthalene) (Poly(1,8-DAN)) to the electrocatalytic reduction of molecular oxygen was investigated, which were electrochemically grown by the potential cycling method on the glassy carbon electrodes. The reduction of oxygen at the polymer and its metal complex polymer coated electrodes were irreversible and diffusion controlled. The Poly(1,8-DAN) and Poly(Co-DAN) films revealed the potential shifts for the oxygen reduction to 30 mV and 110 mV, respectively, in an aqueous solution, compared with that of the bare electrode. Hydrodynamic voltammetry with a rotating ring-disk electrode showed that Poly(1,8-DAN) and Poly(Co-DAN) coated electrodes converted respectively 84% and 22% of $O_2$ to $H_2O$ via a four electron reduction pathway.

• 공업화학
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• 제24권1호
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• pp.49-54
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• 2013

혼합용액에서 nitrate 이온을 선택적으로 제거하기 위해 복합탄소전극을 제조하였다. 질산이온 선택성 수지(BHP55, Bonlite Co.) 분말을 탄소전극 표면에 코팅하여 전극을 제조하였다. 제조한 전극으로 BHP55 셀을 제작하여 chloride, nitrate, sulfate 이온이 혼합된 용액에 대해 축전식 탈염 실험을 수행하였다. 그리고 BHP55 셀에서의 질산 이온 제거량을 이온교환막을 결합한 MCDI 셀의 결과와 비교하였다. BHP55 셀에서 이온의 총 흡착량은 MCDI 셀에서 보다 31% 증가한 $38.3meq/m^2$를 나타냈다. 또한 BHP55 셀에서 질산 이온의 흡착량은 $15.9meq/m^2$ (전체 흡착량의 42%)이었고, 이는 MCDI 셀에서 보다 2.1배 큰 것으로 나타났다. 실험결과 제조한 복합탄소전극은 음이온 혼합용액에서 질산 이온을 선택적으로 제거하는데 매우 효과적임을 알 수 있었다.

• 전기화학회지
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• 제21권1호
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• pp.1-5
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• 2018

본 연구에서는 수소화 붕소 나트륨 ($NaBH_4$)를 이용하여 고온에서 이산화탄소 ($CO_2$)를 환원시켜 붕소가 도핑된 카본을 제조하였고, 이를 카본 펠트에 코팅하여 바나듐 레독스 흐름전지용 전극으로 적용하였다. 전기화학적 성능 평가 결과, 순수 카본펠트 대비 붕소 도핑된 카본으로 코팅된 카본펠트의 가역성이 약 20% 향상되었고 전하 전달 저항이 60% 감소하였다. 충/방전 결과에서는, 에너지 밀도와 에너지 효율이 각각 21%와 12.4% 향상되었다. 이러한 결과는 $CO_2$를 환원시켜 제조한 탄소가 레독스 흐름전지용 전극소재로 사용될 수 있는 가능성을 보여준다.

• Korean Chemical Engineering Research
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• 제49권5호
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• pp.554-559
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• 2011

리튬금속을 음전극으로 사용할 때의 안전성과 전극 특성을 개선하기 위해, 리튬금속 표면에 각기 종류가 다른 3가지의 탄소분말을 리튬금속 표면에 물리적으로 코팅한 전극을 제조하고 이를 리튬 2차전지의 음전극으로 채택하여 충방전 특성을 조사하였다. 일차입자의 입경이 작고 비표면적이 큰 탄소분말로 코팅한 음전극을 채택하는 경우가 충진밀도가 높고 표면 거칠기가 낮으며, 충방전 특성도 우수하게 나타났다. 이러한 탄소분말 코팅 효과는 소형 셀일수록 더욱 유리하게 나타났다.

• Carbon letters
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• 제1권3_4호
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• pp.170-177
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• 2001

Lithium intercalated carbon (LIC) are basically employed as an anode for currently commercialized lithium secondary batteries. However, there are still strong interests in modifying carbon surface of active materials of the anode because the amount of irreversible capacity, charge-discharge capacity and high rate capability are largely determined by the surface conditions of the carbon. In this study, the carbonaceous materials were coated with tin oxide and copper by fluidized-bed chemical vapor deposition (CVD) method and their coating effects on electrochemical characteristics were investigated. The electrode which coated with tin oxides gave the higher capacity than that of raw material. Their capacity decreased with the progress of cycling possibly due to severe volume changes. However, the cyclability was improved by coating with copper on the surface of the tin oxides coated carbonaceous materials, which plays an important role as an inactive matrix buffering volume changes. An impedance on passivation film was decreased as tin oxides contents and it resulted in the higher capacity.

• 한국대기환경학회지
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• 제29권6호
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• pp.773-779
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• 2013

This study was performed to provide the basic data for the function of BTEX removal for compact electrostatic precipitator which are applicable to indoor environment (or closed spaces). For this purpose, the adsorption equilibrium test was conducted for BTEX of activated carbon sheet (ACS) and activated carbon (AC), and the adsorption characteristics of AC and ACS were evaluated using the Langmuir constant which was obtained from the adsorption characteristics, adsorption capacity and regression calculation. The surface area and adsorption pore volume of ACS reduced by 70% and 86%, respectively, as compared to those of AC, and the adsorption capacities of BTEX also showed a similar level. Thus, it is considered that ACS applied electrostatic precipitator is able to remove dust and BTEX simultaneously.

• 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.

• Journal of Biosystems Engineering
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• 제33권6호
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• pp.404-409
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• 2008

Excessive presence of heavy metals in environment affects plants and fruits grown in the contaminated area. Rapid on-site monitoring of heavy metals can provide useful information for efficiently characterizing heavy metal-contaminated sites and for minimizing the exposure of the contaminated food crops to humans. This study reports on the evaluation of gold and glassy carbon (GC) electrodes with mercury or bismuth as a coating material for simultaneous determination of cadmium (Cd) and lead (Pb) in 0.1 M $HNO_3$ solution by anodic stripping voltammetry (ASV). The use of a square-wave voltammetric potential between a working electrode and a reference electrode caused Cd and Pb ions deposited on the electrode surface to be oxidized, thereby generating electric currents at different potentials. The mercury-coated gold electrode was not sensitive enough to detect the usable range of Cd concentrations (1 to 100 ppb). The GC electrodes with mercury or bismuth displayed well-defined, sharp and separate current peaks for Cd and Pb ions when the square-wave voltammetric potentials were applied. The peak currents measured with both mercury- and bismuth- coated GC electrodes were linearly proportional to Cd and Pb concentrations in the range of 1 to 200 ppb in 0.1 M $HNO_3$ with strong linear relationships between concentration and peak current ($R^2$ > 0.95), indicating that both of Cd and Pb ions could be quantitatively measured.

• 대한환경공학회지
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• 제35권10호
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• pp.749-755
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• 2013

본 연구의 목적은 분진제거를 목적으로 제작된 활성탄 전극의 적정 간격 및 적정 전압 그리고 분진 제거효율을 통하여 전극의 적정한 배열에 대하여 알아보고자 수행하였다. 여러 전극 간격 별로 수행한 실험결과로부터 분진의 부착 및 탈착의 빈도수는 전극의 간격이 가까워질수록 증가하였다. 전극 단위면적 당 분진 부착량은 전극간격이 멀어질수록 증가하였지만 총 부착량에 있어서는 전극간격이 가까울수록 전극의 설치수가 많아져서 증가하였다. 이와같은 실험결과로부터 분진제거 챔버에서 전극의 설치간격은 앞단의 경우는 분진 부하량이 높기 때문에 제거량이 많도록 전극의 간격을 멀리하고 후단은 제거효율을 높이기 위하여 전극간격을 가깝게 설치하는 것이 바람직하다고 사료되었다. 그리고 전압 5 kV, 전극간격 2 cm에서 전압의 변화에 따른 분진부착량 실험결과에서 전압의 변화와 부착량과는 상관관계가 없었다.

• 한국입자에어로졸학회지
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• 제17권2호
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• pp.21-27
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• 2021

We developed non-metallic electrodes that can replace metallic electrodes of the electrostatic precipitator(ESP) for the purpose of light weight, corrosion resistance, cost reduction. We manufactured three types of collection electrodes made of stainless steel (M), Carbon ink coating layer-Plastic sheet-Carbon ink coating layer (CPC), and Plastic sheet-Carbon ink coating layer-Plastic sheet (PCP). We studied the collection efficiency of a two-stage ESP using oil mist particles with and without collection stage by changing the flow rate, the material of collection electrode, and the applied voltage of the pre-charger module and the collection module. Here we measured concentrations of particles at diameters of 0.45 ㎛ (CMD; count median diameter) and 3.0 ㎛ (MMD : mass median diameter), as well as PM_2.5 and PM₁₀. As a result of the experiment, two-stage ESP had 22~25% higher collection efficiency in PM_2.5 than one-stage ESP at the same applied voltage. The difference in collection efficiency by varying the materials of collection electrodes was less than 5%. The weight of the non-metallic electrode was only one eighth the weight of the metal electrode. CPC electrode had a thickness of 0.27 mm, which was 1.5 times thinner than a thickness of PCP electrode, so when the flow rate increased, the CPC electrodes couldn't be kept at equal intervals due to the fluttering unlike PCP electrodes. In addition, the PCP-CPC collection module of the present experiment followed the theoretical efficiency based on Deutsch equation and Cochet's charging theory.