Annealing Effect of Self-Assembled Monolayers Generated from Terphenyl Derivatized Thiols on Au(111)

Abstract

We investigated an annealing effect of self-assembled monolayers (SAMs) generated from derivatives of terphenylmethanethiols and tetradecanethiol (C14) on Au(111) using scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy, and contact angle measurement. STM data revealed that the molecules were partially desorbed by the annealing process at temperatures where the contact angle of the hexadecane began to decrease. The decreases in contact angles of both the CF3and CH3-terminated terphenyl SAMs were caused by annealing at 180 °C for 1 h, while a similar decrease began at a lower temperature of 150 °C in the C14 SAMs. From the STM data, a large amount of CH3-terminated terphenyl molecules remained after annealing at 180 °C for 3 h, while a small amount of molecules were observed in the other two SAMs. These data demonstrate that the CH3-terphenyl-derivatized thiol SAM had the highest thermal stability of the three SAMs, and the molecular backbone structure and end group were crucial for determining the thermal stability of the SAMs.

Single Component Self‐Assembled Monolayers of Aromatic Azo‐Biphenyl: Influence of the Packing Tightness on the SAM Structure and Light‐Induced Molecular Movements

“…However, it is still a matter of debate, whether the SAM packing leads to a commensurate molecular lattice, [87][88][89] or whether the strong interchain interaction among the adjacent molecules dominates leading to the formation of incommensurate lattices. [40,90,91] …”

High resolution X-ray photoelectron spectroscopy of 3-mercaptopropionic acid self-assembled films

“…To fit the S 2p 3=2;1=2 doublet, we used a pair of GL peaks with the same full width at halfmaximum (FWHM), the standard spin-orbit splitting of 1.2 eV, and a branching ratio of 2 (S 2p 3=2 /S 2p 1=2 ). been reported for L L -cysteine, an amino acid whose molecular structure is quite similar to MPA [12,15] and for thiols with unsubstituted alkyl chains and with chains containing aromatic moieties [4,[16][17][18][19][20][21][22][23][24]. Before discussing the origin of the S(2) signal it is useful to analyze the evolution of the S 2p core level region during irradiation and heating.…”

Stability of large-area molecular junctions

“…Thermal stability of SAMs on Au surfaces has been studied extensively [17][18][19][20][21][22][23]. Phase transitions and desorption of alkanethiol monolayers on Au(1 1 1) have been observed at elevated temperatures with STM [20,21,[24][25][26][27].…”