Structure of Self-Assembled Monolayers from Amphiphilic Diacetylene Derivatives on Indium-Tin Oxide

Self-assembled monolayers (SAMs) of amphiphilic diacetylene derivatives CH3(CH2) n C≡C-C≡C(CH2)8COOH (n=9, 11, 13, 15) were prepared on an indium-tin oxide (ITO)/glass substrate by chemisorption from the solution. Infrared transmission spectra, visible transmission spectra, and contact angles of water revealed that the SAMs of the diacetylenes are sparse monolayers on the substrate, while the Langmuir-Blodgett monolayer is a condensed one: density of the molecules on the SAMs was approximately estimated to be one molecule/nm2.