• 접착 및 계면
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• 제16권4호
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• pp.152-155
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• 2015

백금은 주조가 쉽고 잘 부식되지 않으며 다양한 화학 반응의 촉매로 사용되는 물질이다. 이러한 다양한 장점 때문에, 배기가스 필터, 부식 방지 전극, 수술 및 생체 이식 재료 등 다양한 분야에서 백금의 활용도가 높다. 그러나, 여느 금속과 마찬가지로 백금 표면은 물에 대한 젖음성이 그다지 크지 않아, 수계 환경에서 표면의 활용성이 좋지 않다. 이에, 본 연구에서는 백금을 매우 간단하면서도 효과적으로 젖음성을 향상시켜 초친수성(superhydrophilic)으로 만들어주는 코팅 방법을 보고하고자 한다. Sodium 3-mercapto-1-propanesulfonic acid 용액을 이용하여 백금 표면을 코팅한 결과, 백금 표면의 물에 대한 접촉 각이 $10^{\circ}$ 이하로 감소하는 것을 확인하였다. 단순 담금 코팅을 통해 만든 sodium 3-mercapto-1-propanesulfonic acid 자가조립 단분자막을 이용해 성공적으로 백금 표면을 초친수성 표면으로 코팅하는데 성공하였다.

• Bulletin of the Korean Chemical Society
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• 제22권2호
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• pp.213-218
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• 2001

Presented are the STM images of self-assembled monolayer of 2-mercaptoethanol on Au(111). Striped structures of ($6{\times}3_{\frac{1}{2}}$), ($5{\times}3_{\frac{1}{2}}$), ($4{\times}3_{\frac{1}{2}}$) and compact-($5{\times}3_{\frac{1}{2}}$) were observed after annealing at $80^{\circ}C.$ Analysis of the ordered structures revealed that the basic fundamental units of the ordered structures were three crystallographically non-equivalent ($3_{\frac{1}{2}}{\times}3_{\frac{1}{2}}$) $R30^{\circ}$ assemblies, and that the way of combination of the assemblies produced the four different structures. The($6{\times}3_{\frac{1}{2}}$) structure ( $\theta$ = 0.33) was composed of one ($3_{\frac{1}{2}}{\times}3_{\frac{1}{2}}$)$R30^{\circ}$ assembly, while the ($5{\times}3_{\frac{1}{2}}$) ( $\theta$ = 0.30) and ($4{\times}3_{\frac{1}{2}}$) ( $\theta$ = 0.38) structures were consisted of two ($3_{\frac{1}{2}}{\times}3_{\frac{1}{2}}$) $R30^{\circ}$ assemblies, separated by 5a and 4a, respectively. Furthermore, the compact-(5X 3½) structure ( $\theta$ = 0.50) was obtained by overlapping three ($3_{\frac{1}{2}}{\times}3_{\frac{1}{2}}$) $R30^{\circ}$ assemblies. In spite of the diversity in the adsorption structures, all the adsorption sites of 2-mercaptoethanol were fundamentally identical. On the other hand, the unannealed primitive SAM of 2-mercaptoethanol was characterized by two observations: a short-range order keeping the adsorbed molecules at approximately $3_{\frac{1}{2}}$ a and the small domains of the striped structures supporting that the observed surface structures on the annealed surface were the extension of the primitive layer of 2-mercaptoethanol. Comparing these observations with the already published structures of ethanthiol, it was concluded that the interaction between the hydroxyl groups of 2-mercaptoethanol might play a significant role in the adsorption step of 2-mercaptoethanol on Au(111) to organize the adsorption structures different from those of ethanthiol.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2002년도 추계총회 및 연구발표회 초록집
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• pp.190.1-190
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• 2002

• Journal of Information Display
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• 제11권4호
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• pp.144-148
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• 2010

In this paper, vertically aligned (VA) liquid crystal (LC) modes were investigated using the alkyl chain ordering effect of self-assembled monolayers (SAMs) prepared on the anisotropic inorganic surface. On the anisotropic surface prepared through oblique ion beam irradiations, the SAM molecules are adsorbed, producing macroscopic alkyl chain ordering, which can determine the pretilt direction of the vertically aligned LC molecules through the intermolecular interactions on the surface.

• Bulletin of the Korean Chemical Society
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• 제23권5호
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• pp.699-704
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• 2002

We characterized nanoelectrode arrays prepared from self-assembled monolayers (SAMs) by adsorption from a solution containing thiolated $\beta$-cyclodextrin ($\beta$-CD) and n-alkanethiol on the gold electrode surface, using electrochemical methods. While the framework, the n-hexadecanethiol SAM, effectively blocked electron transfer between the electrode surface and solution-phase redox probe molecules, the $\beta$-CD cavities isolated in the forests of n-hexadecanethiol molecules were shown to act as an ultramicroelectrode array. The shapes of cyclic voltammograms of probe molecules were related to the number densities of $\beta$-CD molecules within the monolayer films. Probe molecules that have the correct combination of physical and chemical characteristics were shown to effectively penetrate the framework through the $\beta$-CD pores and exchange electrons with the electrode surface.

• Bulletin of the Korean Chemical Society
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• 제24권5호
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• pp.610-612
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• 2003

Octanethiol ($CH_3(CH_2)_7SH$) based self-assembled monolayer on Cu(111) in ultra-high vacuum has been examined using x-ray photoelectron spectroscopy (XPS), temperature programmed desorption (TPD), intergrated desorption mass spectrometry (IDMS), and contact angle analysis. The results show that the octanethiolate monolayers similar to those on gold are formed on Cu(111). The monolayers are stable up to temperatures of about 480 K. Above 495 K the monolayers decompose via the γ-hydrogen elimination mechanism to yield 1-octene in the gas phase. The thiolate head groups on the copper surface change to Cu₂S following the decomposition of hydrocarbon fragments in the monolayers at about 605 K.

• Journal of Electrochemical Science and Technology
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• 제10권2호
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• pp.170-176
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• 2019

Alkanethiol self-assembled monolayers (SAMs) and partially ferrocene (Fc) modifications were applied to the Au ultramicroelectrode (UME) rather than to standard sized electrodes with dimension of millimeters. The electron transfer mediation of the SAMs and Fc modified Au UME was investigated by using a p-aminophenol (p-AP) oxidation reaction via cyclic voltammetry. The electrocatalytic p-AP oxidation at the SAMs and Fc modified Au UME showed a much larger electrocatalytic current density than that at the standard sized electrode due to the fast mass transfer rate at the UME.

• 한국재료학회지
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• 제25권12호
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• pp.647-654
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• 2015

Self-assembled monolayers(SAM) of microspheres such as silica and polystyrene(PS) beads have found widespread application in photonic crystals, sensors, and lithographic masks or templates. From a practical viewpoint, setting up a high-throughput process to form a SAM over large areas in a controllable manner is a key challenging issue. Various methods have been suggested including drop casting, spin coating, Langmuir Blodgett, and convective self-assembly(CSA) techniques. Among these, the CSA method has recently attracted attention due to its potential scalability to an automated high-throughput process. By controlling various parameters, this process can be precisely tuned to achieve well-ordered arrays of microspheres. In this study, using a restricted meniscus CSA method, we systematically investigate the effect of the processing parameters on the formation of large area self-assembled monolayers of PS beads. A way to provide hydrophilicity, a prerequisite for a CSA, to the surface of a hydrophobic photoresist layer, is presented in order to apply the SAM of the PS beads as a mask for photonic nanojet lithography.

• Bulletin of the Korean Chemical Society
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• 제22권11호
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• pp.1192-1196
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• 2001

A diaphorase enzyme electrode for the catalytic reduction of NAD+ , the oxidized form of nicotinamide adenine dinucleotide, has been prepared. The enzyme layer grew spontaneously over an aminoethanethiol self assembled monolayer on a go ld plate electrode. The growth was accomplished by simply dipping the electrode covered by the aminoethanethiol monolayer into a solution containing both glutaraldehyde and diaphorase. We suggested that the glutaraldehyde as a cross-linking reagent was attached to the amino groups of the aminoethanethiol monolayer and the diaphorase enzyme molecules were bound to free aldehyde groups of the glutaraldehyde. Further attachments of the enzyme molecules over the bound enzyme molecules continued with the bridging of the glutaraldehyde. In frequency measurements with a quartz crystal microbalance, the frequency decrease was much more than it was for that of the enzyme monolayer formation, and an enzyme layer thicker than a monolayer was formed. The modified electrode was employed to reduce NAD+ , using diffusional methyl viologen as an electron transfer mediator. The NAD+ was electrocatalytically reduced, and the catalytic current was almost equivalent to that with the multilayered electrode of ten enzyme layers.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.878-881
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• 2004

When it converted solar energy or light energy into chemical energy, it studied the electric charge transfer property of the viologen which is used widely as the electron acceptor for the electric charge delivery mediation of the devices. It was formed monolayer in QCM by self-assembled viologen. The absorbed quantities of viologen's electron through peak current and to analyze the electron transfer property of viologen in redox reaction made experiments in cyclic voltammetry among the electrochemical process. It studied the electron transfer relation of viologen from changing the anion in 0.1M NaCl and $NaClO_4$ electrolyte and the interrelation between scan rate and peak current when scan rate increased twice.