• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.480-484
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• 2013

Since SiOC was introduced as an anode material for lithium ion batteries, it has been studied with different chemical compositions and microstructures using various silicon based inorganic polymers. Poly(phenyl carbosilane) is a SiOC precursor with a high carbon supply in the form of the phenyl unit, and it has been investigated for film applications. Unlike any other siloxane-based polymers, oxygen atoms must be utilized in an oxidation process, and the amount of oxygen is controllable. In this study, SiOC anodes were prepared using poly(phenyl carbosilane) with different heat treatment conditions, and their electrochemical properties as an anode material for lithium ion batteries were studied. In detail, cyclic voltammetry and charge-discharge cycling behavior were evaluated using a half-cell. A SiOC anode which was prepared under a heat treatment condition at $1200^{\circ}C$ after an oxidation step showed stable cyclic performance with a reversible capacity of 360 mAh/g.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1120-1128
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• 2004

The SCBFC was composed of bilayered cathode, the outside of which was modified with $Fe^{3+}$ (graphite-Fe(III) cathode) and the inside of which was porcelain membrane, and of an anode which was modified with $Mn^{4+}$ (graphite­Mn(lV) anode). The graphite-Fe(III), graphite-Mn(IV), and porcelain membrane were designed to have micropores. The outside of the cathode was exposed to the atmosphere and the inside was contacted with porcelain membrane. In all SCBFCS the graphite-Fe(III) was used as a cathode, and graphite-Mn(IV) and normal graphite were used as anodes, for comparison of the function between normal graphite and graphite-Mn(IV) anode. The potential difference between graphite-Mn(IV) anode and graphite-Fe(III) cathode was about 0.3 volt, which is the source for the electron driving force from anode to cathode. In chemical fuel cells composed of the graphite-Mn(IV) anode and graphite-Fe(III) cathode, a current of maximal 13 mA was produced coupled to oxidation of NADH to $NAD^{+}$ the current was not produced in SCBFC with normal graphite anode. When growing and resting cells of E. coli were applied to the SCBFC with graphite-Mn(IV) anode, the electricity production and substrate consumption were 6 to 7 times higher than in the SCBFC with normal graphite anode, and when we applied anaerobic sewage sludge to SCBFC with graphite-Mn(IV) anode, the electricity production and substrate consumption were 3 to 5 times higher than in the SCBFC with normal graphite anode. These results suggest that useful electric energy might possibly be produced from SCBFC without electron mediators, electrode-active bacteria, and extra energy consumption for the aeration of catholyte, but with wastewater as a fuel.

• Environmental Engineering Research
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• v.19 no.4
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• pp.363-367
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• 2014

One chambered sediment microbial fuel cell (SMFC) was equipped with Fe, brass (Cu/Zn), Fe/Zn, Cu, Cu/carbon cloth and graphite felt anode. Graphite felt was used as common cathode. The SMFC was membrane-less and mediator-less as well. Order of anodic performance on the basis of power density was Fe/Zn ($6.90Wm^{-2}$) > Fe ($6.03Wm^{-2}$) > Cu/carbon cloth ($2.13Wm^{-2}$) > Cu ($1.13Wm^{-2}$) > brass ($Cu/Zn=0.24Wm^{-2}$) > graphite felt ($0.10Wm^{-2}$). Fe/Zn composite anode have twisted 6.73% more power than Fe alone, Cu/carbon cloth boosted power production by 65%, and brass (Cu/Zn) produced 65% less power than Cu alone. Graphite felt have shown the lowest electricity generation because of its poor galvanic potential. The estuarine sediment served as supplier of oxidants or electron producing microbial flora, which evoked electrons via a complicated direct microbial electron transfer mechanism or making biofilm, respectively. Oxidation reduction was kept to be stationary over time except at the very initial period (mostly for sediment positioning) at anodes. Based on these findings, cost effective and efficient anodic material can be suggested for better SMFC configurations and stimulate towards practical value and application.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.232-233
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• 2005

Stainless steel has been stably used closed by passivity oxidation films($Cr_2O_3$) is made by neutral atmospheric environment. However, passivity oxidation films of the surface of stainless steel occasionally comes to be destroyed in seawater which is influenced by an environment having halogen ion like $Cl^-$, then, localization corrosion comes to occur. Stainless steel 304 for shaft system material of the small-size FRP fishing boat on seawater environments made an experiment on simulation of sacrifical anode(Al, Zn). Through these experiment and study, following results have been obtained ; According to the field inspection and corrosion simulation, the corrosion on the 2nd class stainless steel shaft(STS 304) in FRP fishing boat has been verified to occur by crevice corrosion and galvanic corrosion etc.. According to the comparison and analysis of Stainless steel 304 shaft materials after simulation leaving unprotected and applying cathodic protection, unprotected shaft specimen of stainless steel 304 was severely corroded, but, protected shaft specimen was not totally corroded. This result is assumed to be made by the facts that anodic reaction, $Fe{\rightarrow}Fe^{2+}$ + $2e^-$, has been restricted by the cathodic protection current of sacrificial anode material.

• Transactions of the Korean hydrogen and new energy society
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• v.12 no.3
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• pp.231-238
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• 2001

Electrocatalytic activity of palladium for hydrogen oxidation and reduction was studied using AC impedance method. The system under study was arranged in electrolytic mode consisting of Pd electrode under study, Pt counter electrode and Nafion electrolyte between them. Two types of Pd electrodes were used - carbon-supported Pd (Pd/C) and Pd foil electrode. Pd/C anode contacting pure hydrogen showed a steady decrease of charge transfer resistance with the increase of anodic overpotential, which is an opposite trend to that found with Pd foil anode. But Pd foil cathode also exhibited a decrease of the resistance with the increase of cathodic overpotential. The relationship between imposition of overpotential and subsequent change of the charge transfer resistance is determined by the ratio of the rate of faradaic process to the rate of mass transportation; if mass transfer limitation holds, increase of overpotential accompanies the increase of charge transfer resistance. Regardless of the physical type of Pd electrode, the anode contacting hydrogen/oxygen gas mixture did not reveal any independent arc originated from local anodic oxygen reduction.

• Journal of Electrochemical Science and Technology
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• v.8 no.2
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• pp.124-132
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• 2017

The performance of electrolytic processes using copper and catalyzed electrodes for enhanced nutrient removal with various catalyzers and combinations of electrodes was evaluated. The catalyzed electrodes removed more ammonia nitrogen than the copper electrode, but higher ammonia removal was achieved using a Pt/Ti anode. On the other hand, electrolysis using the Pt/Cu anode consumed less energy and cost less. During electroreduction, nitrate was better removed by a pair of copper electrodes than by the catalyzed electrodes. During electrolysis of synthetic wastewater, ammonia removal not only increased owing to direct oxidation at the anode, but was also influenced by indirect oxidation at the cathode. Platinum-coated copper and titanium cathodes actively produced oxidizers and thus removed more ammonia than a pure metal cathode. Although phosphorus was removable irrespective of the type of catalyzer, electrocoagulation using the copper electrode achieved complete removal of phosphorus in a period of less than 10 min.

• Journal of Powder Materials
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• v.10 no.1
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• pp.21-25
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• 2003

The Sn - graphite composites were prepared by chemical encapsulation method for anode materials in Li-ion batteries. EDS and XRD analysis confirmed the presence of Sn in the graphite structure. Cyclic voltammometry (CV) measurement shows extra reduction and oxidation peaks, which might to be related to the formations of $Li_xSn$ alloy compounds. Graphite-tin composite electrodes demonstrated higher Lithium storage capacities than graphite electrodes. Due to the nature of fine Sn particles on graphite surface, the graphite-tin composite electrodes have shown a good cycle properties.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.31-34
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• 2004

Feasibility of electrokinetic(EK)-Fenton process and Ozone chemical oxidation were investigated for tile removal of organic contaminants and heavy metals from the contaminated soil. In EK-Fenton process, accumulated electroosmotic flow(EOF) was 80 L for 26 days. Removal efficiency of TPH, As, and Ni were 61%, 36%, and 47%, respectively. The concentration of As was high near the anode due to the transport of anionic As toward the anode, while the concentration of Ni was high near the cathode by the movement of cationic Ni to the cathode. Field scale application of in-situ ozonation was carried out for removal of TPH in 3-D test cell (3 m$\times$2 m$\times$2 m). After 25 days of ozone injection, more than 80% of removal rate was observed through the test cell.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.714-716
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• 2002

Indium tin oxide (ITO) was used as the top anode of top emission inverted organic light emitting diodes (TEIOLEDs). TEIOLEDs were fabricated by deposition of an aluminum bottom cathode, an N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1, 1'-diphenyl-4, 4 1'-diamine (TPD) hole transport layer, a tris-8-hydroxyquinoline aluminum ($Alq_3$) emission layer, and an ITO top anode sequentially. ITO was deposited by r.f. magnetron sputtering without $O_2$ flow during the deposition. After the deposition, the deposited ITO layer was kept under oxygen atmosphere for the oxidation. The characteristics of the TEOILED were affected significantly by the post-deposition oxidation condition.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.873-877
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• 2006

[ $Ta_2O_5$ ] 절연막을 제조하기 위하여 ANODE OXIDATION 공정을 수립하였다. Electrolyte에서의 전압강하는 정전류 모드에서 예상되는 전압의 변화에는 영향을 주지 않지만, 정전압 모드에서 전류의 변화에 영향을 주는 것으로 나타났다. 전해질에서의 전압 강하가 음극산화 전압과 같은 값을 갖는 경우, 전류는$Ta_2O_5$/전해질 계면에서의 전압강하가 증가함에 따라 logarithmic한 형태로 변화하는 것으로 나타났다. 음극 $Ta_2O_5$ 절연막 제조공정에 있어서 전해질에서의 전압 강하는 정전류 모드에서 두께의 손실을 발생시키지만, 정전압 모드에서 다시 복원되기 때문에, 최종 두께는 음극산화 전압에 비례하는 것으로 나타났다. 음극 $Ta_2O_5$ 절연막의 전기적 특성을 조사한 결과, 항복전압은 Electrolyte의 농도와 Anodization Current에 반비례하는 것으로 나타났다. 절연막의 두께가 $1500\AA$일 때 Breakdown Voltage는 350volt. 유전상수는 29로 측정되었다.