Langmuir-Blodgett coatings

Figure 8.13 Langmuir-Blodgett coating of surfactant monolayers.

Langmuir-Blodgett films (LB) and self assembled monolayers (SAM) deposited on metal surfaces have been studied by SERS spectroscopy in several investigations. For example, mono- and bilayers of phospholipids and cholesterol deposited on a rutile prism with a silver coating have been analyzed in contact with water. The study showed that in these models of biological membranes the second layer modified the fluidity of the first monolayer, and revealed the conformation of the polar head close to the silver [4.300]. 

Innocent surfaces do not allow formation of such extended 2D areas as has been demonstrated by using carbon coated copper grids (for TEM) or liquid surfaces as used for Langmuir-Blodgett techniques. Only islands... 

In addition to the two cases discussed above, images of surfaces coated with other organic adsorbates such as cadmium arachidate Langmuir-Blodgett films, (73), DNA (74), di-methyl and di-2-ethylhexyl phthalate (75), and K-24 liquid crystals (Foster, J.S. Frommer, J.E. Nature, submitted) have been obtained in recent publications. 

Fig. 9.1 A schematic illustration of surface coatings with their typical thickness ranging from angstroms to micrometers. Selected are monomolecular layers fabricated by the transfer of Langmuir-Blodgett (LB) films onto solid substrates (1) self-assembled monolayers (SAMs) (2) multilayers thereof (3) polymer-...

Thin films of materials play an important role in modern electronics. Langmuir-Blodgett films (Mort, 1980) are prepared from surface-active molecules that adsorb at the surface of an aqueous solution. The surface is gently compressed to produce a close-packed monolayer, which can be coated on appropriate substrates by dipping at constant surface pressure. The layers so produced are of a precise thickness, and repeated dipping gives multilayers. For example, diacetylenes and other polymerizable... 

Figure 3.1. Constant perimeter Langmuir-Blodgett trough. The pulleys round which the PTFE coated tape passes are mounted on carriages which move so that the perimeter of the enclosed area remains constant but the area enclosed by the tape varies.

Sharma et al. [44] Lactose Milk and dairy products Lactase and galactose oxidase (GaO)/in Langmuir-Blodgett (LB) films of poly(3-hexyl thiophene) (P3HT)/stearic acid (SA) Indium-tin-oxide coated glass plates/0.4 V vs. Pt reference electrode ... 

---