Simple Acid−Base Hydrolytic Chemistry Approach to Molecular Self-Assembly: Thin Films of Long Chain Alcohols Terminated with Alkyl, Phenyl, and Acetylene Groups on Inorganic Oxides Surfaces

Abstract

Self-assembled monolayers of long chain alcohols containing terminal alkyl, phenyl, and acetylene groups on Si(100) (Si/SiO2) substrates have been prepared by a new simple acid−base hydrolytic chemistry route. The two-step process, using Si(NEt2)4 and the desired alcohol, is more efficient than the three-step process, employing SiCl4 and then NEt2H, to yield surface-anchored NEt2 moieties, which react with alcohols to produce self-assembled thin films. The newly formed thin films were characterized by surface wettability measurements, ellipsometry, Fourier Transform infrared spectroscopy, and X-ray photoelectron spectroscopy, and the results show that the monolayers from the two-step process are densely packed and the simple acid−base hydrolytic chemistry route is effective in producing thin films of similar quality as trichlorosilanes on silica and alkanethiols on gold.