• Title/Summary/Keyword: self-assembly monolayer

Search Result 59, Processing Time 0.027 seconds

Electrochemical Properties of Viologen Self-Assembly Monolayer Using QCM (수정진동자를 이용한 Viologen Self-Assembly 단분자막의 전기화학적 특성)

  • 옥진영;신훈규;박재철;장정수;권영수
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.16 no.6
    • /
    • pp.496-500
    • /
    • 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).

Electrochemical Properties of Viologen Self-Assembly Monolayer Using QCM (수정진동자를 이용한 Viologen Self-Assembly 단분자막의 전기화학적 특성)

  • Ock, J.Y.;Song, S.H.;Shin, H.K.;Park, J.C.;Chang, J.S.;Chang, S.M.;Kwon, Y.S.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.11a
    • /
    • pp.403-406
    • /
    • 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$({\Delta}F)$.

  • PDF

The electrochemical study on Viologen SA monolayer using QCM (수정진동자를 이용한 Viologen Self-Assembly 단분자막의 전기화학적 특성)

  • Kim, Jung-Myoung;Yoon, Hee-Chan;Song, Seung-Hun;Kwon, Young-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.05b
    • /
    • pp.21-23
    • /
    • 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 ${\Delta}F$.

  • PDF

Determining the Self-Assembly and Redox Process of a Viologen Monolayer by Electrochemical Quartz Crystal Microbalance (수정진동자를 이용한 Viologen 단분자막의 자기조립화와 산화,환원 반응 측정)

  • Ock, J.Y.;Song, S.H.;Shin, H.K.;Chang, J.S.;Chang, S.M.;Kwon, Y.S.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.05c
    • /
    • pp.23-27
    • /
    • 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 $({\Delta}F)$.

  • PDF

Packing Density Parameters of Palladium Nanoparticle Monolayers Fabricated via Spin-Coating Electrostatic Self-Assembly

  • An, Minshi;Hong, Jong-Dal;Cho, Kyung-Sang;Lee, Eun-Sung;Choi, Jae-Young
    • Bulletin of the Korean Chemical Society
    • /
    • v.29 no.3
    • /
    • pp.623-626
    • /
    • 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.

An Adsorption Process Study on the Self-Assembled Monolayer Formation of Octadecanethiol Chemisorged on Gold Surface

  • Kim, Dong Ho;No, Jae Gwon;Masahiko Hara;Lee, Hye Won
    • Bulletin of the Korean Chemical Society
    • /
    • v.22 no.3
    • /
    • pp.276-280
    • /
    • 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.

Anti-corrosive surface treatment of Mg alloy steel using organic self assembly monolayer technique (유기 단분자막을 이용한 마그네슘 합금 판재 (AZ31)의 내식성 표면처리 기술 연구)

  • Park, Jong-Won;Lee, Gyeong-Hwang;Park, Yeong-Hui
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2009.05a
    • /
    • pp.113-114
    • /
    • 2009
  • 기존의 습식 및 건식 표면처리 공정의 단점을 극복하고, 마그네슘 합금의 가장 큰 문제점인 내식성개선을 위해 열화학기상증착(thermal Chemical Vapor Deposition)법을 이용하여 자기조직화 유기 단분자막(Self-Assembled organic Monolayer, SAM)을 제작하여 마그네슘 합금(AZ31)의 내식성을 검토하였다.

  • PDF

Effect of self-assembled monolayer and aluminum oxide ALD film on a PMMA substrate

  • Shin, Sora;Park, Jongwan
    • Journal of Ceramic Processing Research
    • /
    • v.19 no.6
    • /
    • pp.525-529
    • /
    • 2018
  • The antireflective (AR) coated poly methyl methacrylate (PMMA) substrate was deposited by atomic layer deposition (ALD) on a self-assembled monolayer (SAM) to improve hydrophobicity and mechano-chemical properties of organic thin films. The water contact angles (WCA) were tested to characterize the surface wettability of SAM octadecyltrichlorosilane (OTS) films. Results showed that a contact angle of $105.9^{\circ}$ was obtained for the SAM films with an annealing process, and the highest WCA of $120^{\circ}$ was achieved for the films prepared by the SAM and ALD multi-process. The surface morphology of the SAM films with different assembly times and varying number of ALD cycles was obtained by atomic force microscopy (AFM). The maximum light transmittance for the SAM films on the PMMA substrate reached 99.9% at a wavelength of 450 nm. It was found that the SAM surfaces were not affected at all by the ALD process.