Abstract
Nanometer-scale structure of binary thiol self-assembled monolayers (SAMs) prepared by the electrochemical selective replacement of adsorbed thiols in phase-separated binary SAMs has been studied by scanning tunneling microscopy (STM) and cyclic voltammetry. A phase-separated binary SAM of 1-undecanethiol (UDT) and 3-mercaptopropionic acid (MPA) is used as a starting system. MPA, which has a less negative desorption potential, is selectively removed by controlling the electrode potential, and replaced with 1-hexadecanethiol (HDT) or 11-mercaptoundecanoic acid (MUA). STM images of the UDT layer remaining after the selective removal of MPA exhibit two types of domains: domains with striped structure and domains where thiol molecules are densely packed, suggesting that some UDT molecules are reoriented and form low-density regions where the molecules are aligned flat on the surface. STM images of UDT-HDT and UDT-MUA binary SAMs formed by the replacement show surfaces which are phase-separated in nanometer scale. The size of the domains after the replacement is approximately equal to that of the initial phase-separated UDT-MPA SAM, indicating that the domain size is not significantly affected by the replacement.
| Original language | English |
|---|---|
| Pages (from-to) | 5073-5078 |
| Number of pages | 6 |
| Journal | Langmuir |
| Volume | 15 |
| Issue number | 15 |
| DOIs | |
| Publication status | Published - 1999 Jul 20 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Colloid and Surface Chemistry
- Physical and Theoretical Chemistry
Cite this
Surface structure of binary self-assembled monolayers formed by electrochemical selective replacement of adsorbed thiols. / Hobara, Daisuke; Sasaki, Takayuki; Imabayashi, Shinichiro; Kakiuchi, Takashi.
In: Langmuir, Vol. 15, No. 15, 20.07.1999, p. 5073-5078.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Surface structure of binary self-assembled monolayers formed by electrochemical selective replacement of adsorbed thiols
AU - Hobara, Daisuke
AU - Sasaki, Takayuki
AU - Imabayashi, Shinichiro
AU - Kakiuchi, Takashi
PY - 1999/7/20
Y1 - 1999/7/20
N2 - Nanometer-scale structure of binary thiol self-assembled monolayers (SAMs) prepared by the electrochemical selective replacement of adsorbed thiols in phase-separated binary SAMs has been studied by scanning tunneling microscopy (STM) and cyclic voltammetry. A phase-separated binary SAM of 1-undecanethiol (UDT) and 3-mercaptopropionic acid (MPA) is used as a starting system. MPA, which has a less negative desorption potential, is selectively removed by controlling the electrode potential, and replaced with 1-hexadecanethiol (HDT) or 11-mercaptoundecanoic acid (MUA). STM images of the UDT layer remaining after the selective removal of MPA exhibit two types of domains: domains with striped structure and domains where thiol molecules are densely packed, suggesting that some UDT molecules are reoriented and form low-density regions where the molecules are aligned flat on the surface. STM images of UDT-HDT and UDT-MUA binary SAMs formed by the replacement show surfaces which are phase-separated in nanometer scale. The size of the domains after the replacement is approximately equal to that of the initial phase-separated UDT-MPA SAM, indicating that the domain size is not significantly affected by the replacement.
AB - Nanometer-scale structure of binary thiol self-assembled monolayers (SAMs) prepared by the electrochemical selective replacement of adsorbed thiols in phase-separated binary SAMs has been studied by scanning tunneling microscopy (STM) and cyclic voltammetry. A phase-separated binary SAM of 1-undecanethiol (UDT) and 3-mercaptopropionic acid (MPA) is used as a starting system. MPA, which has a less negative desorption potential, is selectively removed by controlling the electrode potential, and replaced with 1-hexadecanethiol (HDT) or 11-mercaptoundecanoic acid (MUA). STM images of the UDT layer remaining after the selective removal of MPA exhibit two types of domains: domains with striped structure and domains where thiol molecules are densely packed, suggesting that some UDT molecules are reoriented and form low-density regions where the molecules are aligned flat on the surface. STM images of UDT-HDT and UDT-MUA binary SAMs formed by the replacement show surfaces which are phase-separated in nanometer scale. The size of the domains after the replacement is approximately equal to that of the initial phase-separated UDT-MPA SAM, indicating that the domain size is not significantly affected by the replacement.
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U2 - 10.1021/la981631y
DO - 10.1021/la981631y
M3 - Article
AN - SCOPUS:0345633695
VL - 15
SP - 5073
EP - 5078
JO - Langmuir
JF - Langmuir
SN - 0743-7463
IS - 15
ER -