• 대한금속재료학회지
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• 제50권8호
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• pp.549-556
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• 2012

The tribological behavior of CrMoN films with respect to surface chemistry was investigated by using X-ray photoelectron spectroscopy (XPS). All of the films were prepared from a hybrid PVD system consisting of DC unbalanced magnetron (UBM) sputtering and arc ion plating (AIP) sources. The tribological property of the films was evaluated by a friction coefficient using a Ball-on-disk type tribometer. The chemistry of wear track was analyzed by energy dispersive spectroscopy (EDS) and XPS. The friction coefficient was measured to be 0.4 for the CrMoN film, which is lower than that of a monolithic CrN film. EDS and XPS results imply the formation of an oxide layer on the coating surface, which was identified as molybdenum oxide phases, known to be a solid lubricant during the wear test.

• Bulletin of the Korean Chemical Society
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• 제25권7호
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• pp.959-964
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• 2004

A low-dimensional metal frequently exhibits a metal-insulator transition through a charge-density-wave (CDW) or a spin-density-wave (SDW) which accompany it's structural changes. The transition temperature is thought to be determined by the amount of energy produced during the transition process and the softness of the original structure. $AMo_4O_6$ (A=K, Sn) are known to be quasi-one dimensional metals which exhibit metalinsulator transitions. The difference of the transition temperatures between $KMo_4O_6$ and $SnMo_4O_6$ (A=K, Sn) is examined by investigating their electronic and structural properties. Fermi surface nesting area and the lattice softness are the governing factors to determine the metal-insulator transition temperature in $AMo_4O_6$ compounds.

• 한국결정성장학회지
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• 제20권2호
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• pp.80-84
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• 2010

The temperature-programmed reduction of titanium oxide ($TiO_2$) with pure $CH_4$ was used for the preparation of titanium carbide crystallites. The synthesized materials had the different surface areas, indicating that the structural properties of these materials were strong functions of two different heating rates and space velocity employed. The titanium carbide crystallites were active for $NH_3$ decomposition. Since the reactivity varied with changes in the particle size, ammonia decomposition reactivity over the titanium carbides crystallites appeared to be related to the different active species. The reactivities of titanium carbide crystallites were two and three times lower than those of the vanadium and molybdenum carbide crystallites, respectively. These results suggested that the difference in activities might be related to the degree of electron transfer between metals and carbon.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1809-1812
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• 2006

In this paper, the thermally evaporated molybdenum oxide $(MoO_x)$ is investigated as the effective hole-injection material for organic lightemitting devices (OLEDs). The use of $MoO_x$ significantly lowers the operating voltage of OLEDs, insensitive to the anode materials used.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.11-12
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• 2000

An 18.1" Thin Film Transistor Liquid Crystal Display (TFT LCD) monitor adopting high brightness In Plane Switching (IPS) technology was realized. While conventional IPS structure used a Chromium (Cr) and Molybdenum (Mo) for a drain electrode, Indium Tin Oxide (ITO) was proposed and verified in this paper. Black sticky micropeal spacers were introduced for the reduction of light scattering phenomena, which was observed at dark room with the conventional micropeal spacers. With the proposed method, more than 10 % aperture ratio was increased and the excellent image quality was obtained.

• 한국결정성장학회지
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• 제22권6호
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• pp.269-273
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• 2012

Ammonia decomposition over titanium carbides were investigated using eight different samples which have been synthesized by TPR (temperature-programmed reduction) method of titanium oxide ($TiO_2$) with pure $CH_4$. The resulting materials which were synthesized using wo different heating rates and space velocity exhibited the different surface areas. These results indicated that the structural properties of these materials have been related to heating rates and space velocity employed. The titanium carbides prepared in this study proved to be active for ammonia decomposition, and the activity changed with the particle size/surface area. These showed the relationship between ammonia decomposition activity and the different active species. Compared to molybdenum carbide, the titanium carbides were one order of magnitude less active, suggesting the correlation between the activity difference and the degree of electron transfer between metals and carbon in metal carbides.

• KIEE International Transactions on Electrophysics and Applications
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• 제4C권3호
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• pp.106-110
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• 2004

The operating condition of the OLED (organic light-emitting diode) is very sensitive to electrode thickness properties. The electrode thickness is a significant issue in the construction of OLEDs because of its transparency, high conductivity and high efficiency as an injector into organic materials. We carried out a systematic study to optimize the electrode thickness conditions in Indiumtin oxide (ITO), Molybdenum (Mo) and Aluminum (Al). Further, we measured electrode thickness under standard conditions [ITO 1500$\AA$, Mo 2600$\AA$, Al 1500$\AA$]. We also evaluated power consumption. In addition, we analyzed substrate uniformity with IVL measurement results. From these results, it is known that the electrode thickness should be optimized in order to accomplish optimal power efficiency.

• EDISON SW 활용 경진대회 논문집
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• 제5회(2016년)
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• pp.285-287
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• 2016

이황화 몰리브덴(Molybdenum disulfide: $MoS_2$)을 채널(Channel) 물질로 이용하여 metal-oxide-semiconductor(MOS) 구조를 제작하고, 효율적인 제작과정을 제시하였고 특히, Source/Drain의 Doping concentration을 조절하여 효과적인 $MoS_2$ Transistor를 제작 및 시뮬레이션 하였다. 그 후 여러 MOSFET의 특성 분석을 통하여 소자로서의 기능을 확인해보았다. 그리고 특히 채널의 전기적인 특성을 분석하고 채널 내 그리고 contact 사이의 저항 및 mobility의 특성을 알아보았는데, 그 중 Source/Drain Doping Effect와 performance 분석을 통해, 최적화된 $MoS_2$ Transistor를 찾아보았다.

• 한국산학기술학회논문지
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• 제19권1호
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• pp.63-68
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• 2018

본 논문은 이산화탄소 고정 과정이 포함된 인공 광합성 과정을 모사하기 위하여 지구상에 흔히 존재하는 촉매 재료를 이용해 개발한 광화학 반응 시스템(인공나뭇잎)과 시스템 에너지 포집 및 변환 능력에 대한 성능을 조사하기 위한 기초 연구 결과를 제시한다. 본 연구에서 개발한 시스템은 태양광 전지의 전면부에 산화코발트를 도핑 하여 물의 전기분해로 인한 산소 발생이 태양전지 표면에서 직접 발생하도록 하였고, 후면 기판 표면에는 이산화탄소 변환 반응을 위한 효율적인 촉매로 $MoS_2$를 도핑 하여, 전선이 없는 구조로 구성하였다. 직접 태양광 연료 변환 시스템은 약4.5%로 이산화탄소를 일산화탄소와 수소로 변환하여 지속 가능한 연료(합성가스)의 형태로 생산하며, 이는 음극에서 촉매 변환 효율이 75%이상이 될 수 있음을 의미한다. 본 연구는 물의 광분해뿐만 아니라 태양광에 의해 유도된 이산화탄소 전환 과정을 하나의 시스템에서 동시에 실현하여 자연적 광합성 과정을 좀 더 성공적으로 모사할 수 있는 시스템 개발에 기여하였다.

• Journal of Electrochemical Science and Technology
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• 제12권2호
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• pp.246-256
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• 2021

Mo,Cu-doped CeO₂ (CMCuO) nanopowders were synthesized by the nitrate-fuel combustion method aiming to improve the electrical and electrochemical properties of its Mo-doped CeO₂ (CMO) parent by the addition of copper. An electrical conductivity of ca. 1.22·10^-2 S cm^-1 was measured in air at 800℃ for CMCuO, which is nearly 10 times higher than that reported for CMO. This increase was associated with the inclusion of copper into the crystal lattice of ceria and the presence of Cu and Cu₂O as secondary phases in the CMCuO structure, which also could explain the increase in the charge transfer activities of the CMCuO based anode for the hydrogen and carbon monoxide electro-oxidation processes compared to the CMO based anode. A maximum power density of ca. 120 mW cm^-2 was measured using a CMCuO based anode in a solid oxide fuel cell (SOFC) with YSZ electrolyte and LSM-YSZ cathode operating at 800℃ with humidified syngas as fuel, which is comparable to the power output reported for other SOFCs with anodes containing copper. An increase in the area specific resistance of the SOFC was observed after ca. 10 hours of operation under cycling open circuit voltage and polarization conditions, which was attributed to the anode delamination caused by the reduction of the Cu₂O secondary phase contained in its microstructure. Therefore, the addition of a more electroactive phase for hydrogen oxidation is suggested to confer long-term stability to the CMCuO based anode.