Reflection-absorption infrared spectroscop

Szanyi J, Kuhn W K and Goodman D W 1994 CO oxidation on palladium 2. A combined kinetic-infrared reflection absorption spectroscopic study of Pd(IOO) J. Phys. Chem. 98 2978... 

Westermark, G. and Persson, 1. (1998) Chemisorption of tertiary phosphines on coinage and platinum group metal powders. An infrared reflectance absorption spectroscopic, enhanced Raman spectroscopic and surface coverage study. Colloids and Surfaces A -Physicochemical and Engineering Aspects, 144, 149-166. 

Hoshi N, Bae IT, Scherson DA. 2000. In situ infrared reflection absorption spectroscopic studies of coadsorption of CO with underpotential-deposited lead on Pt(lll) in an aqueous acidic solution. J Phys Chem B 104 6049-6052. 

Beck et al. [250] conducted infrared reflection absorption spectroscopic studies on anodic over-oxidation of polypyrrole in the presence of nucleophiles such as II2O, OH", CH3OH, CHjO", Br" and CN". The formation of carbonyl groups occurred at the three-position and hydroxyl groups at the four-position via a di-cation intermediate in aqueous medium, but a bromine substitution at the four-position in the presence of Br nucleophile. Multi-methoxylation, similar to that reported in anodic oxidation of aromatics [256], occurred when the experiment was conducted in methanolic solution with 0.5 M KF as supporting electrolyte according to the following equations... 

X. Bin, Electrochemical and polarization modulation Fourier transform infrared reflection absorption spectroscopic studies of phospholipids bilayers on a Au(lll) electrode surface . PhD thesis, University of Guelph, 2005. 

In addition to the indirect experimental evidence coming from work function measurements, information about water orientation at metal surfaces is beginning to emerge from recent applications of a number of in situ vibrational spectroscopic techniques. Infrared reflection-absorption spectroscopy, surface-enhanced Raman scattering, and second harmonic generation have been used to investigate the structure of water at different metal surfaces, but the pictures emerging from all these studies are not always consistent, partially because of surface modification and chemical adsorption, which complicate the analysis. 

Besides spectroscopic techniques such as infrared-reflection-absorption spectroscopy (IRRAS) and X-ray photoelectron spectroscopy (XPS), SFM-based stiffness imaging was applied in order to detect radiation-induced variations of surface stiffness [180]. For that purpose, when exposing the PE-film to the VUV-radiation, the film was covered with a Ni mesh. Thus, the PE-film was partially masked and exposed to the VUV radiation only within the square-shaped holes of the mesh. After having finished that treatment and having removed the mesh, the sample surface was scanned in force modula-... 

Alpers W and Hiihnerfuss H (1989) The damping of ocean waves by surface films a new look at an old problem. J Geophys Res 94 6251-6265 Benvegnu DJ and McConnell HM (1992) Line tension between liquid domains in lipid monolayers. J Phys Chem 96 6820-6824 Gericke A, Michailov AV, and Hiihnerfuss H (1993) Polarized external infrared reflection-absorption spectroscopy at the air/water interface comparison of experimental and theoretical results for different angles of incidence. Vib Spectroscop 4 335-348... 

Spectroscopic reflectance methods are UV/vis reflectance spectroscopy and infrared reflection absorption spectroscopy (IRRAS) with several variations. For the application of these methods a mirror-Uke electrode surface is needed. This can be avoided if the scattered... 

Strategies for the development of novel catalytic materials and the design of highly active catalysts for DLFC applications largely depend on a detailed understanding of the reaction mechanism and, in particular, of the rate-limiting step(s) during the electrooxidation under continuous reaction conditions. The most commonly used technique in the electrochemical studies of fuel cell reaction mechanisms has been voltammetry, chronoamperometry (chronopotentiometry), in situ spectroscopic techniques, e.g., electrochemically modulated infrared spectroscopy (EMIRS) and infrared reflection-absorption spectroscopy (IRRAS), differential electrochemical mass spectroscopy (DEMS) and ex-situ techniques, e.g.. X-ray photoelectron spectroscopy (XPS) [92]. 

Presented here is a brief review of the vibrational spectroscopic techniques used to characterise ionic liquids on surfaces. Specifically, this review includes results obtained from sum-frequency generation spectroscopy (SFG), infrared reflection-absorption spectroscopy (IRAS), surface-enhanced Raman scattering (SERS) and high-resolution electron energy loss spectroscopy (HREELS). 

Figure 3.7. In-situ reflection-absorption infrared (RAIRS) spectra as a function of catalyst temperature from a Pd(lll) single-crystal surface in the presence of a NO + CO gas mixture (240mbar, Pco/Pno = 1-5) [66]. The data clearly show the appearance of an isocyanate-related band at 2256 cm-1 at temperatures above 500 K. In-situ spectroscopic experiments such as these have proven indispensable to detect and identify key reaction intermediates for the catalytic reduction of NO on metal surfaces. (Figure provided by Professor Goodman and reproduced with permission from the American Chemical Society, Copyright 2003).

There is a number of vibrational spectroscopic techniques not directly applicable to the study of real catalysts but which are used with model surfaces, such as single crystals. These include reflection-absorption infrared spectroscopy (RAIRS or IRAS) high-resolution electron energy loss spectroscopy (HREELS, EELS) infrared ellipsometric spectroscopy. 

Other detection methods. Besides XPS, other chemically sensitive techniques are available to probe the reaction. Surface reflection absorption infrared spectroscopy [130] and electron-energy loss spectroscopy [131] give detailed information on the vibrational states and thus the bonds of surface species. Gas-phase mass spectroscopic techniques provide information about the desorbing species. 

Evidence presented thus far for the putative role played by the photoliberated surfactants has been somewhat circumstantial. Conventional infrared and ultraviolet spectroscopy establish that the photolabile protecting group is photolyzed and the surfactant released under photolysis acid-base indicators, when added to the photosensitive coating, confirm the release of acid for the anionic surfactant derivatives. The surface sensitive spectroscopic techniques of ESCA (Electron Spectroscopy for Chemical Analysis) and RAIR (Reflection-Absorption Infrared) spectroscopy establish the involvement of the surfactant more unequivocally. 

Yang, J. and Tsai, F. P., Development of a solid-phase microextraction/reflection-absorption infrared spectroscopic method for the detection of chlorinated aromatic amines in aqueous solutions. Anal. Sci., 17, 751-756, 2001. 

However, after 1980 the development of in situ infrared spectroscopic techniques have allowed the direct identification of adsorbed intermediates. In terms of methanol oxidation on R, electrochemically modulated infrared reflectance spectroscopy (EMIRS) led to the unambiguous identification of adsorbed CO as the poisoning species. Two adsorbed CO species were identified as being responsible for the poisoning phenomena (i) a linearly bonded species (IR absorption band around 2060 cm ) and (ii) a bridge-bonded species (a small band around 1850-1900 cm ). These results were... 

The most probable orientation of the molecules onto a smooth metal surface can be inferred from reflection-absorption infrared spectroscopic IRRAS... 

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