• Title/Summary/Keyword: surface chemistry

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Adsorption of Some Aliphatic Dimercaptans on the Silver Surface Investigated by Raman Spectroscopy

  • Kwon, Cheol-Kee;Kim, Kwan;Kim, Myung-Soo;Lee, Soon-Bo
    • Bulletin of the Korean Chemical Society
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    • v.10 no.3
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    • pp.254-258
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    • 1989

  • Adsorption of 1,3-propanedithiol, 1,4-butanedithiol, 1,5-pentanedithiol, and 1,6-hexanedithiol on silver surface has been investigated by surface-enhanced Raman spectroscopy. It has been found that the conformations of the adsorbates were mainly affected by steric interaction of the adsorbates with the surface. As the alkyl chain length separating the thiol groups increased, surface stacking efficiency became increasingly important in determining conformation of the adsorbate on the surface.

  • https://doi.org/10.5012/bkcs.1989.10.3.254 인용 PDF

Synthesis and Surface Relief Gratings of Three-Armed Star-Shaped Molecules Bearing 4-(N,N-Diphenyl)Amino-4'-Nitroazobenzene Chromophores

  • Lee, Jung-Eun;Jung, Kyung-Moon;Cho, Min-Ju;Kim, Kyung-Hwan;Choi, Dong-Hoon
    • Macromolecular Research
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    • v.16 no.5
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    • pp.434-440
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    • 2008

  • Three-armed, star-shaped molecules containing 4-(N,N-diphenyl)amino-4'-nitroazobenzene chromophores were synthesized to study the diffraction behavior after inscribing surface relief gratings. The two molecules differed in terms of their mode of chromophore attachment to the core. In compound 5, they were bound to the core laterally through alkylene spacers, whereas the chromophores were tethered perpendicularly to the core in compound 4. Although 60 wt% of the polar azobenzene chromophores was comprised of large molecules, no aggregation behavior was observed in the absorption spectra of the thin films. The surface relief gratings were elaborated on the surface of the molecular films by the two-beam interference method. The dynamics of grating formation were studied in terms of the diffraction efficiency using two different film samples made up of two star-shaped molecules. The maximum diffraction efficiency of D-$(ENAZ)_3$, compound 4, was measured to be about 30%, which was significantly high. The mode of chromophore attachment affected the dynamic properties of the diffraction gratings.

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Zundel- and Eigen-like Surface Hydrated Protons on Pt(111)

  • Kim, Youngsoon;Park, Youngwook;Shin, Sunghwan;Kang, Heon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.167.1-167.1
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    • 2016

  • The interaction between adsorbed water and hydrogen on metallic surfaces is important for fundamental understanding of heterogeneous catalysis and electrode surface reactions in acidic environment. Here, we explore a long-standing question of whether hydronium ion can exist or not on a Pt surface coadsorbed with atomic hydrogen and water. Studies based on mass spectrometry and infrared spectroscopy show clear evidence that hydrogen atoms are converted into hydrated protons on a Pt(111) surface. The preferential structures of hydrated protons are identified as multiply hydrated $H_5O_2{^+}$ and $H_7O_3{^+}$ species rather than as hydronium ions. The multiply hydrated protons may be regarded as two dimensional zundel ($H_5O_2{^+}$) and Eigen cation ($H_7O_3{^+}$) in water-metal interface. These surface-bound hydrated protons may be key surface intermediates of the electrochemical interconversion between adsorbed hydrogen atoms and solvated protons.

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Characterization and Surface-Derivatization of Porous Silicon

  • Lee, Bo-Yeon;Hwang, Min-Woo;Cho, Hyun;Kim, Hee-Chol;Jang, Seunghyun
    • Journal of Integrative Natural Science
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    • v.4 no.3
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    • pp.182-186
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    • 2011

  • Chemical modification of porous silicon surface has been investigated to have different physical surface properties. Porous silicon modified with dodecyl functionality exhibits hydrophobic feature, however the oxidation of porous silicon to modify with hydroxyl group displays hydrophilic properties. Surface characterization for both dodecyl and hydroxyl derivatized porous silicon was investigated by FT-IR spectroscopy. To determine the surface coverage, the amine functionalized surface was reduced by dithiothreitol (DTT) and the released 2-thiopyridone was quantified by UV/vis spectroscopy.

  • https://doi.org/10.13160/ricns.2011.4.3.182 인용 PDF KSCI