• 전기화학회지
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• 제17권4호
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• pp.237-244
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• 2014

We report novel and simple structure of supercapacitors fabricated by using flexible glass fibre separators as templates. This method does not require separate electrodes, binders and high pressure/temperature to build the supercapacitor unit cells as required by the conventional technology. The supercapacitors were fabricated by drop-casting solution mixtures of carbonaceous active materials/gel electrolytes onto two sides of glass fibre separators. Two carbonaceous materials (nanoscaled activated carbons, multi-walled carbon nanotubes) were investigated as electrode materials. The electrochemical measurements reveal that the separatorbased supercapacitors using ACs successfully demonstrated significant mass specific capacitance ($22.3F\;g^{-1}$) and energy density ($9.7Wh\;kg^{-1}$), indicating this method can be useful in fabricating flexible, wearable and stretchable energy storage devices in more straightforward and cost-effective way than current technology.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권5호
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• pp.281-284
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• 1999

In this paper, the electrical conduction, breakdown strength and dielectric properties were investigated in the interfaces of PET films. The volume resistivity and breakdown strength were decreased; especially the specimens with semiconductive layer showed the lowest breakdown strength. This decrease of electrical properties was appeared by increasing charge density in inhomogeneous layer of PET. The dielectric properties of PET did not show significant difference with PET/PET but the films with semiconductive interface layer showed the increase in capacitance and $tan\delta$ was affected by the PET rather than semiconductive layer. It is assumed that the variation of $tan\delta$ was affected by the dielectric polarization and the leakage current(charge).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.332-334
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• 2000

The purpose of this study is to research and develop conducting polymer(CP) composite electrode for supercapacitor. Supercapacitor cell of CP composite electrode with 1M LiClO$_4$/ PC bring out good capacitor performance below 4V. The radius of semicircle of CP composite cell with PAn composite electrode adding 30wt% acetylene black was absolutely small. The total resistance of supercapacitor cell mainly depended on internal resistance of the electrode. The discharge capacitance of supercapacitor cell with PAn composite electrode adding 30wt% acetylene black in 1st and 50th cycles was 27F/g and 31F/g at current density of 1mA/$\textrm{cm}^2$. Supercapacitor cell with PAn composite electrode adding 30wt% acetylene black performed a good cycliability.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.335-338
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• 2000

Carbon is an attractive candidate for use in eletrochemical supercapacitors that depend on charge storage in the electrode/electrolyte international double layer. Property of an electrical double layer capacitor depend both on the technique used to prepare the electrode and on the current collector structure. The study is to research that V$_2$O$_{5}$-flyash-AC composite electrode for supercapacitor. The discharge capacitance of V$_2$O$_{5}$-flyash-AC(70wt%) in 1st and 50th cycle was 18.6F/g and 15.13F/g at current density of 0.5mA/cm$^2$. The discharge process of V$_2$O$_{5}$-flyash (3 : 97)-AC composite electrode is larger than that others.thers.

• E2M - 전기 전자와 첨단 소재
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• 제8권6호
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• pp.752-758
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• 1995

Red emitting CaS:Eu,S electroluminescent(EL) device prepared at 550.deg. C by an electron-beam evaporation technique, demonstrated luminance of 175cd/m$\^$2/ and efficiency of 0.311m/W with 3kHz drive. Luminance was increased with the increase of applied voltage and frequency. From the results of the PL spectrum and the EL spectrum, the CaS:Eu, S device showed emission peak near 640nm resulted from the transition of EU$\^$2+/ 4f$\^$6/5d.rarw.4f$\^$7/. The capacitance of the phosphor layer from the Sawyer-Tower circuit was 10.5nF/cm$\^$2/.

• Transactions on Electrical and Electronic Materials
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• 제13권3호
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• pp.162-164
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• 2012

In this study, we fabricate Pt nanoparticle (NP)-embedded MOS capacitors at room temperature and investigate their memory characteristics. The Pt NPs are separated from each other and situated between the tunnel and control oxide layers. The average size and density of the Pt NPs are 4 nm and $3.2{\times}10^{12}cm^{-2}$, respectively. Counterclockwise hysteresis with a width of 3.3 V is observed in the high-frequency capacitance-voltage curve of the Pt NP-embedded MOS capacitor. Moreover, more than 93% of the charge remains even after $10^4$ s.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1365-1366
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• 2007

Cobalt oxide was composite with MWNT to attain cycle stable by chemical method. We have been considered CoOx is the ideal material for high energy density electrochemical capacitor due to pseudo capacitor reaction. In this study we found that decrease in resistance due to composite MWNT. Also CoOx/MWNT composite material have resulted larger capacitance and exhibits better electrochemical behavior. The structural feature was investigated by using SEM. The CoOx/MWNT composite is not only a promising ultracapacitor material for energy storages but also has a good possibility because of its great capacitive properties, simple preparation and low cost.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1976-1977
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• 2007

This paper introduce the electrical quantities of a three-phase-connected wind induction generator (WIG) under sudden connection of static loads. An intelligent power-system recorder/monitor is employed to measure threephase voltages and currents of the studied system at WIG's terminals and load's terminals for 5 minutes. A laboratory 300 W wound-rotor induction machine driven by a blushless DC motor is utilized as the studied WIG. Since the generated harmonic currents are randomly varied, total harmonic distortion (THD) of current using cumulative probability density function is employed to determine the penetration of harmonic distortion. The results show that the harmonic currents generated by the studied WIG may be severely amplified to a high level by the connected self-excited capacitance at the stator's terminals.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.240-243
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• 1999

(Sr$\sub$0.85/Ca$\sub$0.15/)TiO$_3$thin films were deposited on Pt-coated TiO$_2$/SiO$_2$/Si wafer by the rf sputtering method. Experiments were conducted to investigate the electrical properties of SCT thin films with various top electrode. C-F and C-V measurements show that SCT thin films annnealed at 600$^{\circ}C$ have a larger capacitance than SCT thin films deposited at 400$^{\circ}C$ , and there is nearly no difference between top electrodes. I-V measurement show that Pt top electrode have a good leakage current density of < 10nA/$\textrm{cm}^2$,. making them suitable for DRAM application.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.194-195
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• 2006

Aluminum oxide films directly grown on n-type 6H-SiC(0001) substrates were fabricated by RF magnetron sputtering system. Metal-insulator-semiconductor(MIS) C-V properties with aluminum oxide thin films showed hysteresis and f1at band voltage shift. The dielectric constant of the film calculated from the capacitance at the accumulation region was about 5. Typical gate leakage current density of film at room temperature was the order of $10^{-9}\;A/cm^2$ at the range of within 2MV/cm. The breakdown did not occur at the film within the measurement range.