• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.248-254
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• 2012

During the monolayer assembly of zeolite microcrystals using sonication with stacking (SS) method, the factors that govern the degree of close packing (DCP) between the microcrystals, the rate of attachment (rA) of microcrystals onto the substrate, the degree of coverage (DOC), and the binding strength (BS) between each crystal and the substrate were investigated for each mode of binding linkage (MBL). The tested MBLs were covalent linkage (CL), ionic linkage (IL), and polyelectrolyte-mediated ionic linkage (p-IL). Unlike the monolayers of zeolite crystals assembled on glass with a covalent linkage, the strong BS, very high DOC, and very high DCP do not decrease during monolayer assembly on glass through ionic linkages. This results indicate that the surface migration of crystals undergo linkage-nondestructively when crystals were attached to the substrates through ionic linkages.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1119-1120
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• 2006

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.6
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• pp.496-500
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• 2003

Molecular self-assembled of surfactant viologen are of recent interest because they can from functional electrodes as well as micellar assemblies, which can be profitably utilized for display devices, photoelectrochemical studies and electrocatalysis as electron acceptor or electron mediator. Fromherz et al studied the self-assembly of thiol and disulfide derivatives of viologens bearing long n-alkyl chains on Au electrode surface[1]. The electrochemical behavior of self-assembled viologen monolayer has been investigated with QCM, which has been known as nano-gram order mass detector. The self-assembly process of viologen was monitored using resonant frequency(ΔF) and resonant resistance(R). The redox process of viologen was observed with resonant frequency(ΔF).

• Journal of the Korean Vacuum Society
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• v.22 no.6
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• pp.298-305
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• 2013

Uniform silica nanobeads were synthesized by St$\ddot{o}$ber method and assembled in the form of monolayer on glass substrate using sonication method. Before the assembly of silica nanobeads, glass substrates were treated with molecular linkers, such as CP-TMS and PEI, and nanobeads were dispersed in toluene. In attachment test, SO (sonication without stacking) method and SS (sonnication with stacking) method was used and sonication time was controled. After the experiment, microbalance was use to measure deviation between before and after the attachment experiment then calculate percent of coverage. Minutely observe with SEM (Scanning Electron Microscopy) then select the most close-packed and monolayer assembled cover glass and calculate DOC (Degree of Coverage). In SO method, DOC increased very sharply and reach over 140 percent point, also got lots of multi-layer region. On the other hand, in SS method DOC increased slower than SO method but more close-packed and monolayer assembled.

• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.623-626
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• 2008

Spin-coating electrostatic self-assembly (SCESA) is utilized to fabricate a single layer of carboxylic-acid-coated Pd nanoparticles (NPs) (D??5 nm) on an oppositely charged surface. The packing density of a NP monolayer formed on a rotating solid substrate (3000 rpm) was examined with regards to various parameters, including the particle concentration, the pH, and the ionic strength of the solution. Initially, the packing density grew exponentially with increases in the particle concentration, up to a maximum value (of 8.4 ´ 1011/cm2) at 1.2 wt%. The packing density was also found to increase drastically as the pH decreased and the ionic strength of the solution increased; these trends can be attributed to a reduction in the interparticle repulsions among the NPs in the solution and on the substrate. The best result of this study was achieved in a 1.2 wt% solution at pH 8; under these conditions, an NP monolayer with the highest density (namely, 1.6 ´ 1012/cm2) was obtained.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05b
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• pp.21-23
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• 2002

In this paper, the electrochemical behavior of Viologen self assembly monolayer has been investigated with QCM, which has been known as nano-gram order mass detector. The self assemvly process of Viologen was monitored using resonant frequency $({\Delta}F)$ and resonant resistance(R). QCM measurements indicated a mass adsorption for Viologen assembling on the gold sufrace with a frequency change about 135[Hz] and calculated its surface coverage($\Gamma$) to be $3.5273{\times}10^{-9}[mol/cm^{2}]$. Also reversible redox process was observed and analyzed with ionic interaction at the Viologen/solution interface using ${\Delta}F$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.403-406
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• 2002

Molecular self-assembled of surfactant viologen are of recent interest because they can from functional electroeds as well as micellar assemblies. which can be profitably utilized for display devices. photoelectrochemical studies and electrocatalysis as electron acceptor or electron mediator[1-3]. Fromherz et al studied the se1f-assembly of thiol and disulfide derivatives of viologens bearing long n-alkyl chains on Au electrode surface[4]. In this study, the electrochemical behavior of self-assembled viologen monolayer has been investigated with QCM, which has been known as nano-gram order mass detector. The self-assembly process of viologen was monitored using resonant frequency$({\Delta}F)$ and resonant resistance(R). The redox process of viologen was observed with resonant frequency$({\Delta}F)$.

• Proceedings of the Materials Research Society of Korea Conference
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• 2006.11a
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• pp.18.1-18.1
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• 2006

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.23-27
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• 2003

Molecular self-assembled of surfactant viologen are of recent interest because they can from functional electrodes as well as micellar assemblies, which can be profitably utilized for display devices, photoelectrochemical studies and electrocatalysis as electron acceptor or electron mediator. Fromherz et al studied the self-assembly of thiol and disulfide derivatives of viologens bearing long n-alkyl chains on Au electrode surface. The electrochemical behavior of self-assembled viologen monolayer has been investigated with QCM, which has been known as nano-gram order mass detector. The self-assembly process of viologen was monitored using resonant frequency$({\Delta}F)$ and resonant resistance(R). The redox process of viologen was observed with resonant frequency $({\Delta}F)$.

• Bulletin of the Korean Chemical Society
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• v.22 no.3
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• pp.276-280
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• 2001

The self-assembled formation of octadecanethiol (CH3(CH2)17SH) on a gold substrate was studied using a quartz crystal microbalance (QCM) and a scanning tunneling microscope (STM). From the QCM measurements at vario us concentrations of octadecanethiol solutions in hexane and alcohol, the adsorption process of octadecanethiol onto Au was confirmed to consist of two steps as follows: (i) fast but disordered adsorption and (ii) a thermodynamically controlled rearrangement for uniform packing of octadecanethiol. Also, it was revealed that the adsorption rate became faster in ethanol than in hexane since less solubility of octadecanethiol in ethanol could help the formation of the monolayers. At 5 ${\times}$10-7 M solution, the monolayer formation was monitored by STM. The morphology of monolayer region was initially circular (diameter size: 7.26 $\pm$ 2.1 nm) and gradually changed to a stripe type after several minutes. At higher concentration, the self-assembled monolayer was formed immediately after the solution was introduced to a substrate.