• 한국통신학회논문지
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• 제19권9호
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• pp.1782-1792
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• 1994

$Ti:LiNbO_3$채널형 광도파로와 Asymmetric Coplanar Strip(ACPS) 전극구조를 이용해서, $1.3{\mu}m$에서 동작하는 진형파형 위상 광변조기를 설계, 제작한 다음 변조특성을 관찰하였다. 위상정합이 개선되도록 ACPS 진행파형 전극을 설계하기 위해서 전극과 완충박막의 두께를 포함하여, 전극제원의 해석적 함수로 특성저항, 변조파의 유효굴절률 및 전극손실 등을 고려하였다. Ti 확산방법으로 저손실 채널형 광도파로 제작하였으며, double-spin image reversal 공정을 이용해서 $2.5{\mu}m$ 두께의 전극을 형성하였다. 9GHz 부근에서의 전극구조 공진형상 때문에 변조특성이 제한 되었지만, 2.5GHz 까지는 큰 왜곡없이 변조특성이 관찰되었다.

• 한국환경과학회지
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• 제18권1호
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• pp.49-60
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• 2009

Fabrication and oxidants formation of 1 and 2 component metal oxide electrode, which is known to be so effective to destruct non-biodegradable organics in wastewater, were studied. Five electrode materials (Ru, Pt, Sn, Sb and Gd) were used for the 1 and 2 component electrode. The metal oxide electrode was prepared by coating the electrode material on the surface of the titanium mesh and then thermal oxidation at $500^{\circ}C$ for 1 h. The removed RhB per 2 min and unit W for one component electrode decreased in the following sequences: Ru/Ti>Sb/Ti>Pt/Ti>Gd/Ti>Sn/Ti. The concentration of oxidants generated in 1 and 2 component electrodes was in the order of: $ClO_2$> free Cl>$H_2O_2>O_3$. OH radical was not generated from in entire one and two component electrodes. RhB degradation rate and generated oxidants of the Ru-Sn=9:1 electrode was higher than that of the two component electrode. The exact relationship between the removal of RhB and the generated oxidants concentration was not obvious. However, it was assumed that electrode with high RhB decolorization had high oxidant concentration.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.687-690
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• 2004

Fabrication and characterization of dye-sensitized TiO2 solar cells(DSSC) consisting of spray-coated TiO2 electrode, an electrolyte containing I-/I3- redox couple, and a Pt-coated counter electrode carried out, using mainly FE-SEM and solar simulator. Also, effect of rapid thermal annealing(RTA) temperatue on I-V curves of DSSCS consisting of approximately 10m thickness and $5{\times}5mm2$ active area. No significant difference in the apparent size of TiO2 clusters was observed with increasing RTA temperature. Also, an open circuit voltage(Voc) of approximately 0.70V and a short-circuit photocurrent(Jsc) of 8 to 12mA/cm2 were observed in the TiO2 solar cell. With increasing RTA temperature upto 550oC, photocurrent density of dye-sensitized solar cells was enhanced, leading to enhancing the efficiency of dye-sensitized solar cells having Pt-electroplated counter electrode.

• 한국표면공학회지
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• 제40권3호
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• pp.125-130
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• 2007

Many fundamental studies have been carried out regarding waste water and hazardous gas treatment technology using the photolysis effect of $TiO_2$. However, photolysis of both organic and organic-inorganic binders immobilizing $TiO_2$ makes permanent use impossible. In this study we manufactured a catalytic electrode by nickel-$TiO_2$ composite plating in order to immobilize $TiO_2$. The surface properties according to the current density changes of cathode and concentration changes of $TiO_2$ powder in nickel plating bath has been analysed with EDX, XRF, SEM, Raman spectrometer etc. The characterization of the catalytic electrode in decomposition of organic compound has been obtained by using UV-Visible spectrophotometer through analysing concentration changes of methyl orange solution containing the catalytic electrode vs. time with projecting UV-light in the solution. The study shows that a catalytic electrode of nickel-$TiO_2$ composite plating with high-efficiency in decompostion of organic compound has been formed under high concentration of $TiO_2$ powder and low current density of cathode.

• 한국세라믹학회지
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• 제51권4호
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• pp.362-366
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• 2014

Dye-sensitized solar cells (DSSCs) were synthesized using a $0.25cm^2$ area of a $TiO_2$ nanoparticle layer as the electrode and platinum (Pt) as the counter electrode. The $TiO_2$ nanoparticle layers (12 to 22 ${\mu}m$) were screen-printed on fluorine-doped tin oxide glass. Glancing angle X-ray diffraction results indicated that the $TiO_2$ layer is composed of pure anatase with no traces of rutile $TiO_2$. The Pt counter electrode and the ruthenium dye anchored $TiO_2$ electrode were then assembled. The best photovoltaic performance of DSSC, which consists of a $18{\mu}m$ thick $TiO_2$ nanoparticle layer, was observed at a short circuit current density ($J_{sc}$) of $14.68mA{\cdot}cm^{-2}$, an open circuit voltage ($V_{oc}$) of 0.72V, a fill factor (FF) of 63.0%, and an energy conversion efficiency (${\eta}$) of 6.65%. It can be concluded that the electrode thickness is attributed to the energy conversion efficiency of DSSCs.

• 전기학회논문지
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• 제58권12호
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• pp.2436-2440
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• 2009

In this work, TCO-less dye-sensitized solar cells (DSCs) using Ti-mesh layer is fabricated for high-efficient low-cost solar cell application. The Ti-mesh metal can replace TCO in the photo-electrode part of DSCs, thus the cell structure is composed of a glass/dye sensitized TiO2 particle/ Ti-mesh layer/electrolyte/Pt sputtered counter electrode/ glass. The Ti-mesh electrode with high conductivity can collect electrons from the $TiO_2$ layer and allows the ionic diffusion of $I^-/I_3^-$ through the mesh hole. Thin Ti-mesh ($\sim40{\mu}m$ in thickness) electrode material is processed using rapid prototype method. The efficiency of prepared TCO-less DSCs sample is about 1.45 % ((ff: 0.5, Voc: 0.52V, Jsc: 5.55 $mA/cm^2$).

• 전기화학회지
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• 제12권3호
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• pp.287-294
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• 2009

$TiO_2$가 첨가된 탄소복합전극을 제조 Capacitive deionization(CDI)에서의 제염효과에 대하여 고찰하였다. 본 연구에서는 탄소전극과 탄소복합전극을 제조하여 순환전류전압법과 충전-방전 평가를 하였으며 이때의 이온제거율에 대하여 고찰하였다. 순환전류전압법으로 1 mV/s의 전위주사속도에서 측정한 결과 탄소전극은 125 F/g, 탄소복합전극의 축전용량은 243 F/g으로 2배 증가됨을 확인하였다. 탄소복합전극의 $TiO_2$의 함량은 10 wt.%로 고정하였으며 $TiO_2$가 첨가됨에 따라 전기이중층 흡착량이 증가되어 이온제거율이 탄소전극보다 25% 증가되었다.

• 한국군사과학기술학회지
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• 제13권4호
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• pp.699-707
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• 2010

Electric-field-induced electron emission from the three kinds of $Pb(Zr_{0.56}Ti_{0.44})O_3$ ferroelectric cathodes with different electrode structure has been investigated. Regardless of the electrode structures, a threshold field of the each cathode was 2.5-2.6kV/mm, which is 3 times higher than the coercive field of $Pb(Zr_{0.56}Ti_{0.44})O_3$ material. Although the waveform of the electron currents was affected by the structure of the electrode, no significant difference for the emission properties such as the peak current and the pulse width was observed from the three kinds of the cathodes. However, the current density of the cathode was dependent on the electrode structure. From the simulation of electric field distribution, the surface flashover, and the injury region of the cathode surface, it was proved that the prime electrons were initiated at the electrode-ceramic-vacuum triple point by field emission and the emission currents were strongly enhanced by the surface plasma.

• 한국환경과학회지
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• 제19권1호
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• pp.89-96
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• 2010

The separation of $TiO_2$ wastewater carried out by an electrocoagulation/flotation process, which had various operating parameters. The effect of electrode material (aluminum and four dimensionally stable electrode), applied current (0.07~0.5 A), electrolyte concentration (0~1 g/L), solution pH (3~11), initial turbidity (1000~20000 NTU) and suspended solid concentration (5000~25000 mg/L) were evaluated. Turbidity removal efficiency of the soluble anode (aluminum), which could produce metal ions, was higher than that of the dimensionally stable electrode. Considering operation time, turbidity removal and electric power, optimum current was 0.19 A. The more NaCl dosage was high, the less electric power was required. However, optimum NaCl concentration was 0.125 g/L considered removal efficiency, operation time and cost. Initial $TiO_2$ concentration did not affected turbidity removal on the electrocoagulation/flotation operation. The electrocoagulation/flotation process was proved to be a very effective separation method in the removal of $TiO_2$ from wastewater.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.461-462
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• 2005

In order to improve the efficiency of dye-sensitized solar cell (DSC), $TiO_2$ electrode screen-printed on transparent conducting oxide (TCO) substrate was sintered in variation with different temperature(350 to $550^{\circ}C$). $TiO_2$ electrode on fluorine doped tin oxide (FTO) glass was assembled with Pt counter electrode on FTO glass. I-V properties of DSC were measured under solar simulator. Also, effect of sintering temperature on surface morphology of $TiO_2$ films was investigated to understand correlation between its surface morphology and sintering temperature. Such surface morphology was observed by atomic force microscopy (AFM). From the measurement results, at sintering temperature of $500^{\circ}C$, both efficiency and fill factor of DSC were mutually complementary, enhancing highest fill factor and efficiency. Consequently, it was considered that optimum sintering temperature of $\alpha$-terpinol included $TiO_2$ paste is at $500^{\circ}C$.