• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2248-2250
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• 1999

In this paper, showering discharge type ozonizer has been designed and manufactured. The ozonizer is equipped with three electrodes(central electrode of screw shape, internal electrode and external electrode) of cylinder shape. This paper describes the following two characteristics: (1) The characteristics of discharge with variation of output voltage of AC H.V source, flux of oxygen supplied gas and discharge voltage. (2) The characteristics of ozone generation by varying flux and discharge power.

• Journal of the Korean Chemical Society
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• v.36 no.3
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• pp.383-392
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• 1992

(Bakelite-A)-(2,2'-Bipyridine)-Ni(Ⅱ) Nitrate complexes were tested as ion exchanger for nitrate ion-selective electrode. The experimentally observed selectivity and electrode characteristics were relatively in good agreement with the exchanger lipophilicity in the membrane phase. Based on chemical composition, mechanisms for exchange with nitrate ion and internal electrical conduction were postulated. Analytical application to the determination of nitrate were studied.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.11
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• pp.758-763
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• 2014

Soil microbial fuel cells (SMFC) have gained a great attention as an eco-friendly technology that can simultaneously generate electricity and treat organic pollutants from the contaminated soil. We evaluated the effect of electrode spacing and size on the performance of SMFC treating soil contaminated with organic pollutants. Maximum power density decreased with increase in electrode distance or decrease in electrode size, likely due to higher internal resistance. The maximum voltage and power density decreased from 326 mV and $19.5mW/m^2$ with 4 cm of electrode distance to 222 mV and $5.9mW/m^2$ with 9 cm of electrode distance. In case of electrode size test, the maximum voltage and power density generated was 291 mV, $0.34mW/m^3$ when both of anode and cathode area were $64cm^2$ with 4 cm of electrode distance. The maximum voltage decreased by 19~29% when the anode area decreased to $16cm^2$ while only 3~12% of voltage decreased with cathode area decrease. The maximum power density decreased by 49~68% with decreasing anode size, and by 29~47% with decreasing cathode size. These results showed that the anode area had more significant effects than the cathode area on the power generation of SMFC which has a high internal resistance due to a coexistence of soil and wastewater in the reactor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.124-127
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• 2000

The purpose of this study is to research and develop PAn-Carbon composite electrode for Supercapacitor. Supercapacitor cell of PAn-Carbon composite electrode with 1M $LiClO_{4}/IPC$ brings out good capacitor performance below 4.0V. The radius of semicircle of PAn-Carbon composite electrode adding 30wt% Acetylene Black was absolutely small. The total resistance of Supercapacitor cell mainly depended on internal resistance of he electrode. The discharge capacitance of PAn-Carbon on composite with 30wt% Acetylene Black in 1st and 50th cycles was 29 and 31F/g at current density of $1mA/cm^2$. The capacitance of PAn-Carbon composite with 30wt% Acetylene Black capacitor was larger than that of PAn capacitor without Acetylene Black. The coulombic efficiency of supercapacitor at discharge process of 1 and 50 cycles were 94 and 100%. respectively. PAn-Carbon composite Supercapacitor with 30wt.% Acetylene Black content showed good capacitance and stability with cycling.

• Proceedings of the KIEE Conference
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• 2004.07e
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• pp.88-91
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• 2004

In order to improve ozone generation, we experimentally investigated the silent discharge plasma and ozone generation characteristics of a multi-discharge type ozonizer. Ozone in a multi-discharge type ozonizer is generated by superposition of a silent discharge plasma, which is simultaneously generated in separated discharge spaces. A multi-discharge type ozonizer is composed of three different kinds of superposed silent discharge type ozonizers, depending on the method of applying power to each electrode. We observed that the discharge period of the current pulse for a multi-discharge type ozonizer can be longer than that of silent discharge type ozonizer with two electrodes and one gap.Hence, ozone generation is improved up to 17185 ppm and 783 g/kwh for the superposed silent discharge type ozonizer for which an AC high voltages with a 180 phase difference were applied to the internal electrode and the external electrode, respectively, with the central electrode being ground

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.3
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• pp.279-285
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• 2008

CNC (Carbon Nano Colloid) was used as an additive to the positive electrode to improve the discharge performance of sealed lead-acid batteries, The cathode active material ($PbO_2$) has a relatively low utility of less than 60 % compared with other kind of batteries, such as Ni-MH and Lithium ion, In this study, to overcome the above-mentioned problem we investigated the effects of CNC addition on the enhancement of electrical connection with not-utilized $PbO_2$ and resultantly electrical conductivity of electrode, We examined low rate discharge capacities, high rate discharge capacities and internal resistances of the batteries containing various amounts of CNC. From these results, we found out that the addition of CNC into the positive electrode made a significant improvement in high rate discharge capacity, We also suggested the optimum content of CNC material in positive electrode.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1999.11a
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• pp.17-22
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• 1999

In this paper a new discharge type ozonizer comprising the superpose operation of silent and surface discharge is presented. The ozonizer consists of two concentric glass tubes with three type of discharge electrodes : the external electrode(EE), the internal electrode(IE) and the central electrode(CE). By varying the structure of IE and materials of CE, we analyzed the characteristics of ozone related different parameters including $O_{3con}$, $O_{3g}$, and $O_{3Y}$. Using Cu made CE it was found the O3con is higher with Cu tape than that with Cu coil wound IE. At Q = 1[l/ min] the values of O3con were found as 3000[ppm] with Cu tape wound IE and 1898[ppm] with Cu coil wound IE. Then using SUS wire made CE with Cu tape wound IE at Q = 1[ι/ min] the maximum value of O3con was found as 5632[ppm]. It was observed that both $O_{3con}$ and $O_{3y}$ are higher with SUS made CE than that with Cu made CE. The maximum values of $O_{3Y}$ were found as 79[g/kWh] with Cu made CE and 170[g/kWh] with SUS wire made CE.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.346.1-346.1
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• 2014

Porous nano crystalline $TiO_2$ is currently used as a working electrode in a dye-sensitized solar cell (DSSC). The conventional working electrode is comprised of absorption layer (particle size:~20 nm) and scattering layer (particle size:~300 nm). We inserted window layer with 10 nm particle size in order to increase transmittance and specific surface area of $TiO_2$. The electrochemical impedance spectroscope analysis was conducted to analysis characterization of the electronic behavior. The Bode phase plot and Nyquist plot were interpreted to confirm the internal resistance caused by the insertion of window layer and carrier lifetime. The photocurrent that occurred in working electrode, which is caused by rise in specific surface area, increased. Accordingly, it was found that insertion of window layer in the working electrode lead to not only effectively transmitting the light, but also increasing of specific surface area. Therefore, it was concluded that insertion of window layer contributes to high conversion efficiency of DSSCs.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1255-1257
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• 1997

In order to obtain key technologies for a kW class internal humidifying proton-exchange-membrane fuel cell (PEMFC) a single cell with a large electrode area has been designed and manufactured and the performance of large area membrane/electrode assemblies (MEAs) has been evaluated by using the single cell. A small area MEA made of commercial E-TEK electrode and Nafion 117 membrane showed a performance of 0.7V, $300mA/cm^2$ whereas large area MEA made of catalyst layer on carbon support and Nafion 117 showed a lower performance. To improve the performance of large MEA direct coating of catalyst was carried out on the membrane using a screen printer.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3128-3132
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• 2010

A disposable solid-state pH sensor was realized by utilizing two nanoporous Pt (npPt) electrodes and a copolyelectrolytic junction. One nanoporous Pt electrode was to measure the pH as an indicating electrode (pH-IE) and the other assembled with copolyelectrolytic junction was to maintain constant open circuit potential ($E_{oc}$) as a solid-state reference electrode (SSRE). The copolyelectrolytic junction was composed of cationic and anionic polymers immobilized by photo-polymerization of N,N'-methylenebisacrylamide, making buffered electrolytic environment on the SSRE. It was expected to make. The nanoporous Pt surrounded by a constant pH excellently worked as a solid state reference electrode so as to stabilize the system within 30 s and retain the electrochemical environment regardless of unknown sample solutions. Combination between the SSRE and the pH-IE commonly based on nanoporous Pt yielded a complete solid-state pH sensor that requires no internal filling solution. The solid state pH sensing chip is simple and easy to fabricate so that it could be practically used for disposable purposes. Moreover, the solid-state pH sensor successfully functions in calibration-free mode in a variety of buffers and surfactant samples.