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Updated: Apr 26, 2026
A Technique to Functionalize and Self-assemble Macroscopic Nanoparticle-ligand Monolayer Films onto Template-free Substrates
Published on: May 9, 2014
Formation of highly ordered self-assembled monolayers of alkynes on Au(111) substrate
Tomasz Zaba1, Agnieszka Noworolska, Carleen Morris Bowers
1Smoluchowski Institute of Physics, Jagiellonian University , ul. Reymonta 4, 30-059 Krakow, Poland.
Abstract:
Self-assembled monolayers (SAMs), prepared by reaction of terminal n-alkynes (HC≡C(CH2)nCH3, n = 5, 7, 9, and 11) with Au(111) at 60 °C were characterized using scanning tunneling microscopy (STM), infrared reflection absorption spectroscopy (IRRAS), X-ray photoelectron spectroscopy (XPS), and contact angles of water. In contrast to previous spectroscopic studies of this type of SAMs, these combined microscopic and spectroscopic experiments confirm formation of highly ordered SAMs having packing densities and molecular chain orientations very similar to those of alkanethiolates on Au(111). Physical properties, hydrophobicity, high surface order, and packing density, also suggest that SAMs of alkynes are similar to SAMs of alkanethiols. The formation of high-quality SAMs from alkynes requires careful preparation and manipulation of reactants in an oxygen-free environment; trace quantities of O2 lead to oxidized contaminants and disordered surface films. The oxidation process occurs during formation of the SAM by oxidation of the -C≡C- group (most likely catalyzed by the gold substrate in the presence of O2).
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