Study of Surfaces and Interfaces

Such achievements have been made possible because of the substantial progresses obtained in other areas of chemistry and physics—particularly concerning the synthesis and characterization of complex chemical systems, and the study of surfaces and interfaces. In this perspective, electrochemistry is a very powerful tool not only for characterizing a supramolecular system, but also for operating the device. Indeed, molecular devices, as their macroscopic counterparts, need energy to operate and signals to communicate with the operator. Electrochemistry can be an interesting... 

Penfold, J. and Thomas, R. K. (1990). The application of the specular reflection of neutrons to the study of surfaces and interfaces. J. Phys. Condens. Matter 2 1369-1412. 

Some physical properties of semiconductor electrodes depend on the orientation of the crystal, and surface properties vary from one crystal plane to the other. It is therefore very important in studies of surface and interface effects that the proper surface is selected. A semiconductor crystal can be cut by sawing or by cleavage. Cleavage in... 

This is a third-order nonlinear spectroscopic method that does not involve time delay. It consists of sending two coherent beams on a sample simultaneously one in the visible-UV region and the other one in the IR region and observing the photon that is emitted at the sum of their frequencies and is concomitant with the absorption of two photons, one in each of the two incident beams (72). The spectroscopic regions of the two incident beams are regions of transparency of the sample. The emitted photon requires absence of a centre of symmetry at molecular level to appear. It means that it practically does not appear in the bulk of a liquid, for instance, which is isotrope and consequently displays a centre of inversion in the average, but may appear on its surface, or at the interface between this liquid and another medium, where this centre of inversion disappears. It will consequently be most useful in the study of surfaces and interfaces, particularly the structures of the molecules thereon that can be deduced from the spectrum of these surfaces or interfaces (73). In many situations, it may be the unique tool to study liquid surfaces and interfaces and we shall see this in Ch. 9, which is devoted to liquid water-related examples. 

A quantity of interest in many studies of surfaces and interfaces is the concentration of adsorbed atomic or molecular species. The SHG/SFG technique has been found to be a useful probe of adsorbate density for a wide range of interfaces. The surface sensitivity afforded by the method is illustrated by the results of figure Bl.5.9 [72]. These data show the dramatic change in SH response from a clean surface of silicon upon adsorption of a fraction of a monolayer of atomic hydrogen. 

The study of surfaces and interfaces has always been hampered by the search of appropriate experimental tools. Optical surface second-harmonic generation (SSHG) has been shovm to be a powerful method and has thus been widely applied over the last decades in surface science. Phenomena like adsorption processes, surface reconstruction or interfacial chemical reactivity have been investigated at both solid and liquid surfaces and have already been extensively reviewed in the past [1-5]. At Uquid/ liquid interfaces experimental results are far less numerous, despite the growing interest for these interfaces which... 

Lomov AA, Bushuev VA, Karavanski VA (2000) Study of surface and interface roughnesses in porous silicon by high-resolution X-ray methods. Crystallogr Rep 45 842-847 Lopez-Villegas JM, Navarro M, Papadimitriou D, Bassas J, Samitier J (1996) Structure and non-uniform strain analysis on p-type porous silicon by X-ray reflectometry and X-ray diffraction. Thin Solid Films 276 238-240... 

The usefulness of surface-sensitive techniques in the study of surfaces and interfaces of conjugated polymers. 

Abstract The photoemission spectroscopy is one of the most important techniques for the study of surfaces and interfaces, enabling you to determine the oxidation state, the dispersion of the phases and the dependence of the atomic concentration with depth. It allows determining the chemical state and several other surface informations. 

The photoemission spectroscopy is one of the most important techniques for the study of surfaces and interfaces, enabling you to determine the chemical composition, the oxidation state, the dispersion of the phases, and the dependence of the atomic concentration with depth. This information is relevant to areas such as microelectronics, pharmacy, metallurgy, materials, and chemistry. Some examples of applications that rely on this study are biocompatibility of bone implants, drug coating technology of thin films, polymers, construction of nanostructured materials, and the development of new catalysts for the industry and for the environmental area. 

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