Langmuir monolayers, electrochemistry

In a different application of HT electrochemistry involving an alkanethiol-coated working electrode. Miller and coworkers devised a way to measure the flow rate of a Langmuir monolayer along the metal-alkanethiol/solution interface [37, 40,41). In this experiment, an alkanethiol-coated gold electrode is initially touching... 

Photosystem I, Monolayers, Langmuir-Blodgett films, Absorbance, Electrochemistry. 

Instead of c, for adsorption from the gas phase, it is custom to use the partial pressure. For that isotherm it has to be assumed (a) that a localized adsorption (i.e., finite and defined number of adsorption sites) takes place at an isotropic surface, (b) that the adsorbed particles do not interact with each other, and (c) that the maximum coverage is a monolayer of the adsorbed particles [iii]. About the importance of the Langmuir isotherm in electrochemistry see - adsorption isotherm. 

Doron, A., Katz, E., Tao, G., and Willner, I. Photochemically-, chemically- and pH controlled electrochemistry at functionalized spiropyran monolayer electrodes, Langmuir 1997,13,1783-1790. 

We have not considered here alignment techniques, such as SiOx deposition or alignement by monolayer (Langmuir) deposition on surfaces. Details on these techniques of surface alignment can be found elsewhere [5-9]. We also do not discuss recently introduced active (command) surfaces, where the anchoring conditions are controlled by light [55], electrochemistry [56] and electric field [57]. 

The use of electrochemistry to characterize Langmuir films directly at the air/water interface was introduced in the mideighties. Since then two classes of experiments have been developed (1) horizontal touch (HT) experiments involving a planar working electrode held directly above the air/water interface and contacting a monolayer film spread on the water surface and (2) two-dimensional (2D) electrochemical measurements involving line microelectrodes positioned in the plain... 

Electrochemistry of LB films of fullerenes has been widely studied and remains the subject of much research effort from both theoretical and experimental approaches. Bard etal. have studied basic electrochemistry of Ceo fullerene LB films on an electrode in acetonitrile solutions [23]. The study indicated that reduction of the fullerene films could form insoluble films with incorporated electrolyte cations or lead to dissolution. The study on Cgo LB films has become a focus of considerable interest however, it is difficult to fabricate high-quality LB films of pure Cgo due to its intrinsic hydropho-bicity. Kajiyama et al. applied a multistep creep method as an LB technique for constructing a fairly homogeneous Ceo monolayer, which is regularly packed in a hexagonal array [44]. Kunitake etal. developed the electrochemical replacement method to form epitaxial adlayers of fullerenes on Au(lll) surfaces [45]. The wet process method consists of the transfer of Langmuir films of fullerene onto iodine-modified Au(lll) surfaces at an air-water interface followed by the electrochemical removal and replacement of iodine adlayers with fullerene adlayers in solution. The fullerene adlayers prepared by this method showed excellent quality and uniformity. A visuahzing... 

During the last decade the field of electrochemistry has witnessed a very fast progress on the modification of electrode surfaces. From the predominant use of random polymeric structures, prevalent in the electrode modification efforts of the late 70s and early 80s, electrochemists have learnt to control the molecular architecture of the electrode-solution interface to a degree that was clearly out of reach a decade ago. Many electrode modification methods developed recently rely on the use of thiolate self-assembled monolayers (SAMs) [1-3]. These systems offer unparalleled ease of preparation and levels of molecular organization close to those that can be reached with Langmuir-Blodgett film methods. Therefore, electrodes derivatized with unfunctionalized or functionalized alkanethiolate monolayers have been the subject of extensive research work during the last few years [4, 5]. 

Zhou, W. Baunach, T. Ivanova, V. Kolb, D. M. 2004. Structure and electrochemistry of 4-4 -dithiodipyridine self-assembled monolayers in comparison with 4-mercaptopyridine self-assemhled monolayers on Au(l 11). Langmuir 20 4590 595. 

Esplandiu MJ, Hagenstrom H, Kolb DM (2001) Functionalized self-assembled alkanethiol monolayers on Au (111) electrodes 1. Surface structure and electrochemistry. Langmuir 17 828-838... 

Gorodetsky, A. A. Barton, J. K. Electrochemistry using self-assembled DNA monolayers on highly oriented pyrolytic graphite. Langmuir 2006, 22, 7917-7922. 

Hayes, W.A. and Shannon, C. (1996) Electrochemistry of surfacemixed monolayers of 4-aminothiophenol and thiophenol on Au. Langmuir, 12, 3688-94. 

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