• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.861-868
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• 1996

Skeletal isomerization reaction known as exothermic reaction shows possible maximum yield of i-butene from n-butene at $110^{\circ}C$ over $Pt/MoO_3/SiO_2$. Compared with conventional catalyst such as silica, zeolite, alumina etc., $Pt/MoO_3/SiO_2$ demonstrates higher yield while by-products except 2-butene do not form. Faster H spillover rate over $Pt/MoO_3/SiO_2$ is demonstrated via isothermal reduction experiment at $110^{\circ}C$ compared to the rate over $Pt/MoO_3/Al_2O_3$. Overall isomerization rates are proportional to higher spillover rates from Pt onto $MoO_3$ surface. The skeletal isomerization reaction is composed of two elementary steps. First, carbonium ion formation over Pt crystallites by H spillover. Second, carbenium ion formation over $MoO_3$ followed by formation of i-butene. Moreover, it is suggested that H spillover step from Pt surface onto $MoO_3$ is assumed to be the rate determining step and control the overall isomerization rate.

• Bulletin of the Korean Chemical Society
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• v.30 no.6
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• pp.1353-1356
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• 2009

This study examined the adsorption of CO on a Mo(110) surface by Thermal Desorption Spectroscopy (TDS) and synchrotron-radiation based photoemission spectroscopy (SRPES). CO desorption was observed at approximately 400 K ($\alpha$-CO) and > 900 K ($\beta$-CO). When CO was exposed to Mo(110) at 100 K, it showed a tilted structure at low CO coverage and a vertical structure after saturation of the tilted CO. After heating the CO-precovered sample to 900 K, a broad peak at 12 eV below the Fermi level was identified in the valence level spectra, which was assigned to either the 4$\sigma$-molecular orbital of CO, or 2s of dissociated carbon. TDS results of the $\beta$-CO showed a first order desorption. These results are in a good agreement with the observations of CO adsorption on W(110) surfaces.

• Journal of the Korean Vacuum Society
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• v.4 no.2
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• pp.150-155
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• 1995

Mo 단결정 표면에 황을 흡착시켜 형성된 상층구조를 AES와 LEED로써 연구하였다. 황의 피복률은 sulfur gun으로부터 생성되는 S2 flux로써 조절하였으며, 여러 가지 흡착된 황의 상층구조를 LEED로써 관찰하였다. 황화된 Mo 표면에서 탈산소반응(HDO)의 모델 분자로서, Furan의 흡착과 반응을 승온반응분광법(TPRS)으로 조사하였다. 낮은 온도에서 Furan 분자의 헤테로 원자는 직접 이탈하여 안정한 기체상의 반응 생성물인 일산화탄소를 형성하였으며, 이 반응은 Mo의 (100) 및 (110)면에서 각각 깨끗한 표면 및 황화된 표면에 관계없이 일어났다. 이를 바탕으로 Mo 표면에서 Furan의 분해반응에 대한 메카니즘을 제안하였다.

• Proceedings of the KWS Conference
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• 1995.04a
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• pp.110-113
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• 1995

• Applied Science and Convergence Technology
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• v.26 no.5
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• pp.110-113
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• 2017

The two-dimensional layered $MoS_2$ has high mobility and excellent optical properties, and there has been much research on the methods for using this for next generation electronics. $MoS_2$ is similar to graphene in that there is comparatively weak bonding through Van der Waals covalent bonding in the substrate-$MoS_2$ and $MoS_2-MoS_2$ heteromaterial as well in the layer-by-layer structure. So, on the monatomic level, $MoS_2$ can easily be exfoliated physically or chemically. During the $MoS_2$ field-effect transistor fabrication process of photolithography, when using water, the water infiltrates into the substrate-$MoS_2$ gap, and leads to the problem of a rapid decline in the material's yield. To solve this problem, an epoxy-based, as opposed to a water-based photoresist, was used in the photolithography process. In this research, a hydrophobic $MoS_2$ field effect transistor (FET) was fabricated on a hydrophilic $SiO_2$ substrate via chemical vapor deposition CVD. To solve the problem of $MoS_2$ exfoliation that occurs in water-based photolithography, a PPMA sacrificial layer and SU-8 2002 were used, and a $MoS_2$ film FET was successfully created. To minimize Ohmic contact resistance, rapid thermal annealing was used, and then electronic properties were measured.

• Polymer(Korea)
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• v.24 no.2
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• pp.237-244
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• 2000

Phenolic resin used as a precursor of carbonized matrix for carbon-carbon composites was modified by addition of molybdenum disilicide (MoSi$_2$) in various concentrations of 0, 4, 12 and 20% by weight to improve the anti-oxidation properties of the composites. The green body was manufactured by a prepreg method and was submitted to carbonization up to 110$0^{\circ}C$. In this work, the oxidation behavior of carbon-carbon composites with MoSi$_2$ as an oxidation inhibitor was investigated at the temperature range of 600-100$0^{\circ}C$ in an air environment. The carbon-carbon composites with MoSi$_2$ showed a significantly improved oxidation resistance due to both the reduction of the porosity formation and the formation of mobile diffusion barrier for oxygen when compared to those without MoSi$_2$. Carbon active sites should be blocked, decreasing the oxidation rate of carbon. This is probably due to the effect of the inherent MoSi$_2$ properties, resulted from a formation of the protective layer against oxygen attack in the composites studied.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.258-259
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• 2015

$CuInSe_2$(CIS)층에 Na의 첨가는 태양전지 셀의 효율을 향상시키는데 도움을 주는 것으로 알려져 있다. 본 연구에서는 Na이 없는 코닝 유리 기판에 Mo/Mo-Na 이중 박막을 후면 전극으로 이용하여 CIS층의 Na소스로 작용하도록 하였다. CIS/Mo/Mo-Na 다층 박막을 제조한 후, AES분석을 통해 Na은 Mo/Na층과 CIS층의 계면과 CIS층의 표면에 주로 분포하는 것을 알 수 있었다. XRD분석을 통해서 Na함량이 증가할수록 Mo박막의 우선성장면 (110)면의 피크는 감소하였고, CIS의 우선 성장면인 (112)면은 점차 증가하여 Mo-Na층이 200 nm일 때, 최댓값을 가지고 이후로는 감소하는 경향을 보인다. CIS의 결정은 기판에 수직인 방향으로 덴드라이트 성장을 한다. Mo-Na층이 200 nm까지는 밀도가 높은 결정이 성장되지만, 그 이상으로 Na농도가 증가하면 결정 입자의 크기는 다소 성장하지만 밀도가 현저하게 감소한다. 이 결과들로 보아 CIS층의 Na농도조절은 Mo/Mo-Na 이중층의 두께조절을 통해 가능하며, Na이 CIS층에 초과되어 첨가되면 특성이 저하된다.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.10a
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• pp.110-110
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• 2017

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2001.11a
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• pp.110-110
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• 2001

• Proceedings of the Korean Institute of Landscape Architecture Conference
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• 2003.10a
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• pp.108-110
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• 2003