• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.6
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• pp.519-523
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• 2006

$LiFePO_4$ has been received attention as a potential cathode material for the lithium secondary batteries. In our study, $LiFePO_4$ cathode active materials were synthesized by a solid-state reaction. It was modified by coating $TiO_2$ and carbon in order to enhance cyclic performance and electronic conductivity. $TiO_2$ and carbon coatings on $LiFePO_4$ materials enhanced the electronic conductivity and its charge/discharge capacity. For lithium polymer battery applications, $LiFePO_4$/solid polymer electrolyte (SPE)/Li and $LiFePO_{4}-TiO_{2}/SPE/Li$ cells were characterized by a cyclic voltammetry and charge/discharge cycling. The electrode with $LiFePO_{4}-carbon-TiO_{2}$ in PVDF-PC-EC-$LiClO_{4}$ electrolyte showed promising capacity of above 100 mAh/g at 1C rate.

• Corrosion Science and Technology
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• v.19 no.2
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• pp.100-107
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• 2020

The demand for powder-coated steel used in the marine industry is increasing owing to their superior corrosion resistance. However, the powder coatings used in commercial products can deteriorate easily by the penetration of brine. In an attempt to suppress brine penetration into the powder coating and significantly increase the corrosion resistance, three types of oxide particles were added to the coating. Electrochemical impedance spectroscopy tests in 3.5% NaCl solution were performed to evaluate the corrosion behaviors of the powder coating with oxide particles. The results showed that the addition of SiO₂ particles to a powder coating severely decreased the corrosion resistance due to the easy detachment of agglomerated SiO₂ particles with a coarse size from the coating layer. In contrast, the TiO₂ and SnO₂-added coatings showed better corrosion resistance, and the TiO₂-added coating performed best in the test conducted at room temperature. However, conflicting results were obtained from tests conducted at a higher temperature, which may be attributed to the effective suppression of brine penetration by the fine SnO₂ particles uniformly distributed in the coating.

• Korean Journal of Materials Research
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• v.17 no.3
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• pp.125-131
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• 2007

[ $TiO_{2}-solution$ ] was aaded in $SiO_{2}-solution$ by various composition. $SiO_{2}-TiO_{2}$ thin films were obtained by the dip-coating method on the $SiO_{2}$ glass substrates, and then heat-treated at various temperature. Nano-size $TiO_{2}$ particles dispersed $SiO_{2}-TiO_{2}$ films showed absorption peak by quantum size effect at short wavelength region $350{\sim}400nm$, which made them good candidates for non-linear optical materials and photo-catalytic materials. The thickness of $SiO_{2}-TiO_{2}$ films were $300{\sim}430nm$. The contact angle of $SiO_{2}-TiO_{2}$ films for water was $5.3{\sim}47.9^{\circ}$, and therefore it is clear that $SiO_{2}-TiO_{2}$ films have super hydrophilic properties and the self-cleaning effects.

• Journal of the Korean Electrochemical Society
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• v.9 no.2
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• pp.59-63
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• 2006

The study is coated tin(IV) oxide coated on the titanium substrate electrodes by electrodepositon and dip-coating method and studied about that physical and electrochemical characterization by coating methods. After titanium substrate is etched in HCl, electrodespotion is coated $SnCl_2{\cdot}2H_2O$ in nitrate solution by pulse technique, dip-coating method is also used $SnCl_2{\cdot}2H_2O$ in 1;1V% HCl and coated by dipping and annealing process. tin(IV) oxide coated on titanium substrate electrodes by two coating methods are studied x-ray diffraction (XRD), scanning electron microscopy (SEM) to compare physical characterization of electrode and potential window by cyclic voltammetry (CV) to observe electrochemical characterization.

• Corrosion Science and Technology
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• v.5 no.4
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• pp.149-152
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• 2006

$BaTiO_3$ coatings were prepared by micro arc oxidation (MAO) method. Only $Ba(OH)_2$ was dissolved in the electrolyte and process time was less than 30 min. Commercial purity $Ba(OH)_2$ (97%) containing $BaCO_3$ as impurity was used in preparing the electrolyte. XRD showed that the coating was composed of largely $BaTiO_3$, and in some process conditions, small quantity of impurity, $BaCO_3$, was characterized in the coating layer. The quantity of $BaCO_3$ could be controlled to negligible quantity by regulating the applied voltage and duration time of the MAO process.

• Journal of the Korean Ceramic Society
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• v.37 no.4
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• pp.338-344
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• 2000

Grain boundary chemistry and electrical characteristics of polycrystalline BaTiO3 ceramics, which were prepared with sol-gel surface-coated semiconducting powders, were investigated. Mn ions were coated on the powder surface by sol-gel coating-techniques. The additives coated on the surface of the powders were observed to be present near the grain boundaries of the ceramics. The ceramics exhibit the PTCR characteristics with a resistivity jump ratio(Pmax/Pmin) of about 2$\times$103. With raising the temperature from room temprature to 20$0^{\circ}C$, the oxidation state of the Mn ions varied from Mn3+ to Mn2+ in the coating layers. Near the grain boundaries an excessive negative charge layer of about 20nm was formed.

• Proceedings of the Membrane Society of Korea Conference
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• 1993.04a
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• pp.35-35
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• 1993

튜브형 $\alpha-Al_2O_3$ 담체에 졸-겔 침지코팅법과 가압코팅(pressurized coating) 법으로 boehmite 졸과 극미세 입자 SiO$_2$ 및 TiO$_2$ 졸을 코팅한 후 200$\circ$C~500$\circ$C 에서 열처리하여 복합분리막을 제조하였다.

• Journal of the Korea Safety Management & Science
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• v.15 no.3
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• pp.127-132
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• 2013

This study shows an air-purification test by the UV lamp on which TiO2 catalyst is deposited with glass fiber in the reactor chamber. This test was based on the fundamental data of air-purifier as assessing a removing ability on various contaminants such as CH3COOH, NH3, NO and SO2 as variation of the TiO2 coating, the wave of UV lamp, and the additive CaO. As a result, the highest decomposing removal ratio was shown when 5-times coated glass fiber was used. It can be due to the recombination reaction of electrons and electron-hole in the loaded CaO. Thus, the decomposing removal ratio increased as the recombination ratio decreased. In addition, it was confirmed that the decomposing removal ratio lowered when CaO was considerably deposited because it hided the lamp of OH-1 radical.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.161-161
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• 2011

Titanium (IV) dioxide (TiO2) is one of the most attractive d-block transition metal functional oxides. Many applications of TiO2 such as dye-sensitized solar cells and photocatalyst have been widely investigated. To utilize solar energy efficiently, TiO2 should be well-aligned with a high surface area and promote the charge separation as well as electron transport. Herein, the TiO2 nanotubes were successfully fabricated by a template-directed method. The electrospun PEO(Polyethylene oxide, Molecular weight, 400k)fibers were used as a soft template for coating with titanium dioxide using an atomic layer deposition (ALD) technique. The deposition was conducted onto a template at 50$^{\circ}C$ by using titaniumisopropoxide [Ti(OCH(CH3)2)4; TTIP] as precursors of TiO2. While the as-deposited TiO2 layers onto PEO fibers were completely amorphous with atomic layer deposition, the TiO2 layers after calcination at 500$^{\circ}C$ for 1 h were properly converted into polycrystalline nanostructured hallow TiO2 nanotube. The TiO2 nanotube with high surface area can be easily handled and reclaimed for use in future applications related to solar cell fabrications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.14-16
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• 1995

Pb($Zr_{0.52}Ti_{0.48}$)$O_3$ ceramic thin films were fabricated from an alkoxide-based solution by Sol-Gel method. Pb($Zr_{0.52}Ti_{0.48}$)$O_3$ co-ramic thin films were formed by spin coating method on Pt/$SiO_2$/Si substrate at 4000[rpm] for 30 [sec]. Coated specimens were dried on the hot-plate at 400[$^{\circ}C$] for 10[min]. The coating process was repeated 6 times and then sintered at temperature between 500 ~ 800[$^{\circ}C$] for 1 hour. The ferroelectric perovskite phases precipitated under the sintering of 700[$^{\circ}C$] for 1 hour. Pb($Zr_{0.52}Ti_{0.48}$)$O_3$ thin film sintered at 700[$^{\circ}C$] for 1hour showed good dielectric constant (2133) and dielectric loss (2.2[%]) Properties. The switching voltage, switching time and leakage currents density were 3.0[V], 1.7[${\mu}$sec] , 160[pA/$\textrm{cm}^2$] repectively.