Fluorous Property of a Short Perfluoroalkyl-Containing Compound Realized by Self-Assembled Monolayer Technique on a Silicon Substrate

Abstract

Fluorous properties represented by the water-and-oil repellency are perfluoroalkyl (Rf) compounds-specific characters, which are widely used for surface coating of glass, an electronic device and textiles for preventing water and greasy fouling. According to the stratified dipole-arrays (SDA) theory, the minimum Rf length of (CF2)7 is theoretically necessary for realizing the fluorous property. Unfortunately, however, compounds involving this chemical unit are strictly banned for fabrication because of a concern of environmental pollution, which is a big dilemma. Here, we show that the fluorous property can be realized by the self-assembled monolayer (SAM) technique even with a short Rf-containing compound, since the SAM technique makes the best use of the self-aggregation property of the Rf groups, and it readily makes the molecules immobile.

Infrared active surface modes found in thin films of perfluoroalkanes reveal the dipole–dipole interaction and surface morphology

“…The shift of 21 cm −1 is too large, however, to attribute the changes to the molecular aggregation or related things on considering that the νs(CF 2 ) band is known to exhibit a very minute change in aggregation or crystallization. 4,20 On closer inspection, the new band is also found on a shoulder of the intermediate spectra, which makes an impression on us that it may be related to the molecules that are directly interacting with the substrate surface. The same shape change was, however, reproduced on other materials (data not shown).…”

“…This band is known to be a useful marker to discuss the molecular packing. 1,2,4,7,19 When the packing becomes loose, the peak position moves to a higher wavenumber.…”

“…Perfluoroalkyl (R f ) compounds are attracting increased interest in recent years from the view point of physical chemistry 1,2 involving surface chemistry [3][4][5] and surface spectroscopy, 6,7 since understanding of material properties of a single molecule is being rapidly progressed in a separated manner from that of macroscopic properties in a lucid theoretical framework in the stratified dipole-array (SDA) theory. 1,2 Various experiments on surface chemistry and spectroscopy have already confirmed that R f compounds are intrinsically different from hydrocarbons.…”

Zero-to-Two Nanoarchitectonics: Fabrication of Two-Dimensional Materials from Zero-Dimensional Fullerene

“…Functional materials in huge varieties have been prepared and fabricated through efforts in organic synthesis [ 7 , 8 , 9 , 10 ], polymer chemistry [ 11 , 12 , 13 ], coordination chemistry [ 14 , 15 , 16 , 17 ], supramolecular chemistry [ 18 , 19 , 20 , 21 ], and the other materials science especially for nanostructured materials [ 22 , 23 , 24 , 25 ]. Various fabrication techniques including the self-assembled monolayer (SAM) method [ 26 , 27 , 28 ], Langmuir–Blodgett (LB) technique [ 29 , 30 ], and layer-by-layer (LbL) assembly [ 31 , 32 ] have indispensable roles in the developments of functional materials as well as contributions with emerging materials such as nanocarbon materials [ 33 , 34 ] and nanoporous materials [ 35 , 36 ].…”

Nanoarchitectonics for Coordination Asymmetry and Related Chemistry

“…For example. combination of molecular/materials self-assembly with non-equilibrium process included thin film procedures such as self-assembled monolayer (SAM) method, 20 Langmuir-Blodgett (LB) technique, 21 and layer-by-layer (LbL) assembly 22 often gives orientationcontrolled surface structures and intentional sequential layer motifs. With these advantageous natures in structural fabrications, the nanoarchitectonics concept is capable of being used universally in various fields.…”