Rose bengal dye on thiol-terminated bilayer for molecular devices.
Recently, it has become increasingly important to control molecular layers, especially with regard to the formation of bilayers, in order to avoid electrical shorts in molecular electronics. In this paper, we report on the characterization of an in situ thiol-terminated bilayer that is formed by hydrogen bonding between the amine group of an aminoalkanethiol monolayer on a gold surface and the free amine group of aminoalkanethiolates in a bulk solution. We also report on the use of a rose bengal (RB) monolayer on a thiol-terminated bilayer for the purpose of application in a molecular memory device. Using surface-sensitive techniques such as grazing angle Fourier transform infrared (FT-IR) spectroscopy, quartz crystal microbalance (QCM) measurement, ellipsometry, X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV), we characterized a thiol-terminated bilayer (TUA-AUT) and an RB functionalized monolayer on a bilayered surface (RB-TUA-AUT). For a control experiment, we prepared a single RB monolayer attached by an ethanethiol group to a gold surface. In order to assess the feasibility of the present approach with respect to application in molecular electronics, we tested the switching property of the self-assembled monolayers (SAMs) using conducting-probe atomic force microscopy (CP-AFM). The RB monolayer on the bilayered surface exhibited hysteresis, while a single RB monolayer gave an electrical short.
Bang
Gyeong Sook
GS
National Creative Research Initiative, Center for Smart Molecular Memory, IT Convergence Technology Research Division, IT Convergence & Components Laboratory, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-350 South Korea.
Park
Jonghyurk
J
Lee
Junghyun
J
Choi
Nak-Jin
NJ
Baek
Hee Yoel
HY
Lee
Hyoyoung
H
D001665:Binding Sites; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D015394:Molecular Structure; D012395:Rose Bengal / Q000138:chemical synthesis / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties
D005456:Fluorescent Dyes; D008051:Lipid Bilayers; D013438:Sulfhydryl Compounds; D012395:Rose Bengal; D006046:Gold