Fourier-transform reflection absorption infrared spectroscopy

Recent work in our laboratory has shown that Fourier Transform Infrared Reflection Absorption Spectroscopy (FT-IRRAS) can be used routinely to measure vibrational spectra of a monolayer on a low area metal surface. To achieve sensitivity and resolution, a pseudo-double beam, polarization modulation technique was integrated into the FT-IR experiment. We have shown applicability of FT-IRRAS to spectral measurements of surface adsorbates in the presence of a surrounding infrared absorbing gas or liquid as well as measurements in the UHV. We now show progress toward situ measurement of thermal and hydration induced conformational changes of adsorbate structure. The design of the cell and some preliminary measurements will be discussed. 

B.B. Perston, M.L. Hamilton, B.E. Williamson, PW. Harland, M.A. Thomson and P.J. Melling, Grazing-angle fiber-optic Fourier transform infrared reflection-absorption spectroscopy for in situ detection and quantification of two active pharmaceutical ingredients on glass. Anal. Chem., 79, 1231-1236 (2007). 

PVI-1 and UDI have been Investigated as emtl-oxldatlon agents for Cu in dry air at elevated temperatures [ -30]. Fourier transform Infrared reflection-absorption spectroscopy TFT-IR RAS) was... 

Fourier transform infrared reflection-absorption spectroscopy (FT-IFRAS) is applied to the study of corrosion protection of copper by an organic coating. Poly-N-vinyliroidazole (PVI(D) and poly-4(5)-vinylimidazole (PVI(4)) are demonstrated to be effective new polymeric anti-corrosion agents for copper at elevated temperatures. Oxidation of copper is suppressed even at 400° C. PVI(1) and PVI(4) are more effective anti-oxidants than the most commonly used corrosion inhibitors, benzotriazole and undecyllmldazole, at elevated temperatures. These new polymeric agents are water soluble and easy to treat the metal surface. 

Fourier transform infrared reflection-absorption spectroscopy studies (FTIR-RAS) by Tolbert and coworkers (Zondlo et al., 1998) of the uptake of HNO, on ice at 185 K have shown that a supercooled liquid forms on the surface upon evaporation of water, the ice film becomes more concentrated in HN03 and at stoichiometries of 3 1 and 2 1 H20 HN03, respectively, NAT and NAD crystallize out. The reactions of C10N02 and N2Os with the ice also led to the formation of supercooled H20-HN03 liquid layers on the ice surface. 

The ILs interact with surfaces and electrodes [23-25], and many more studies have been done that what we can cite. As one example, in situ Fourier-transform infrared reflection absorption spectroscopy (FT-IRAS) has been utilized to study the molecular structure of the electrified interphase between a l-ethyl-3-methylimidazolium tetrafluoroborate [C2Qlm][BF4] liquid and gold substrates [26]. Similar results have been obtained by surface-enhanced Raman scattering (SERS) for [C4Cilm][PFg] adsorbed on silver [24,27] and quartz [28]. 

Figure 9.12 Spectroelectrochemical cell for Fourier-transform infrared reflection absorption spectroscopy (FTIRRAS). (A) Cell components showing Teflon bar for controlling the sample path length (B) retroreflection absorption optics for use with this cell. [From I.T. Bae, X. Xing, E.B. Yeager, and D. Scherson, Anal. Chem. 61 1164 (1989). Copyright 1989 American Chemical Society.]...

Golden WG (1985) Fourier Transform Infrared Reflection-Absorption Spectroscopy. In Ferraro J R, Basile LJ (eds) Fourier Transform Infrared Spectroscopy, Applications to Chemical Systems, vol 4, Academic, Orlando, pp 315 - 344 Golden WG, Dunn DS, Overend J (1981) J Catalysis 71 395 Goldman A, Saunders RS (1979) J Quant Spectrosc Rad Transfer 21 155... 

F. Caruso, D.N. Furlong, K. Ariga, I. Ichinose, T. Kimitake, Characterization of Polyelectrolyte-Protein Multilayer Films by Atomic Force Microscopy, Scanning Electron Microscopy, and Fourier Transform Infrared Reflection-Absorption Spectroscopy , Langmuir, 14,4559 (1998)... 

It has been suggested that the first step of reaction (6) may be the formation of a carboxylic species COOHads. Carboxyl radicals have indeed been observed by Zhu et al." for potentials lower than 0.65 V using Fourier Transform infrared Reflectance Absorption Spectroscopy with the Attenuated Total Reflection mode (ATR-FTtR). Moreover Anderson et al." made numerical simulation which indicated that the formation of an adsorbed carboxylic species was energetically more favorable. Here, it has to be noted that the electro-oxidation of CO being a stracture sensitive reaction (sensitive to the superficial stracture symmehy" and to the presence of surface defects) this species can be used to study the activity of a catalyst but also as a molecular probe to characterize the catalytic surface. ... 

Golden WG. (1985) Fourier Transform Infrared Reflection-Absorption Spectroscopy. Academic Press, Orlando. 

Hoffmann F M and Weisel M D 1993 Fourier transform infrared reflection absorption spectroscopy studies of... 

FTIRRAS Fourier transform infrared reflection absorption spectroscopy... 

The controlled deposition of ruthenium on well-defined surfaces, such as Pt(hkl) [95-103] and Au hkl) [38-40], has been characterized by electrochemical measurements, Fourier transform infrared reflection-absorption spectroscopy (FT-IRRAS), XPS and STM measurements. The interest in these studies is mainly concentrated on the ruthenium modification of a platinum surface because of its extreme importance in electrocatalysis. It has been demonstrated that a ruthenium-deposited Pt( 111) substrate showed an extremely high activity in methanol oxidation compared to ruthenium-deposited Pt(hkl) electrodes with other crystallographic orientations [98, 99]. 

Ethylene-vinyl acetate copolymer, terpene-phenol resins, polyethylene oxide, PMMA and some of their blends were solution cast on basic (aluminium oxide) and acidic (hydroxylated glass) substrates. Fourier transform infrared reflection absorption spectroscopy (IRRAS) was used to determine both the nature and the free energy of interfacial adduct formation in the polymer/metal systems. A correlation between IRRAS and adhesive strength may be used to predict both the acid-base work of adhesion and the density of interfacial interacting sites. 14 refs. 

Rgure 8 SNIFTIRS spectra of 2,5-dihydroxythiophenol adsorbed on a gold electrode at different electrode potentials and normalized to a 0.1V reference potential 0.2 V (A), 0.4 V (B), 0.5 V (C), 0.6 V (D), 0.4 V (E), and 0.1 V (F). (Reprinted with permission from Sasaki T, Bae IT, Scherson DA, Bravo BG, and Soriaga MP (1990) Oxidation-state changes of molecules irreversibly adsorbed on electrode surfaces as monitored by in situ Fourier transform infrared reflection absorption spectroscopy. Langmuir6 1234-1237 American Chemical Society.)... 

The layer-by-layer structure of dithiol SAM and CdS monolayer was confirmed with X-ray photoelectron spectroscopy, Fourier transform infrared reflection-absorption spectroscopy, and inductively coupled plasma mass spectroscopy at each step of composite-film preparation. Photocurrent measurements revealed that the mono-layers of CdS nanoparticles were immobilized without mutual aggregation of particles [36]. Cadmium selenide nanoparticles were prepared electrochemically on gold substrates modified with alkanethio-lated -cyclodextrin SAMs [37]. 

When the potential was scanned to 0 mV, a pair of waves due to the redox of the azobenzene moiety appeared, in addition to that of ferrocene in the first potential scan (sohd line in Fig. 13c). The wave due to the redox of azobenzene, however, disappeared, and the redox potential and the peak separation of the redox wave due to ferrocene became more negative and smaller, respectively, in the second scan (dotted line in Fig. 13c). The redox potential and the peak separation returned to the original values after UV irradiation. These changes in the electrochemical characteristics of the latter electrode were reversible. On the basis of the structural analysis results by in situ Fourier-transform infrared reflection absorption spectroscopy (FT-IRRAS), we concluded that the electrochemical properties, that is, the redox potential and the charge transfer rate, of the ferrocene group in the SAM-modified gold electrode can be reversibly controlled... 

Fourier transform infrared reflection absorption spectroscopy (FT-IRAS) of some biologically important molecules adsorbed on metal surfaces... 

Abstract The technique of Fourier transform infrared reflection absorption spectroscopy (FT-IRAS) has been used to characterize thin films of proteins and amino acids formed on metal surfaces. The films were spontaneously adsorbed from solution onto each metal. All infrared spectra were taken on dried films. The infrared spectra were obtained by reflecting the radiation from the film covered surface at a high angle of incidence ( 75°) and with the radiation polarized parallel to the plane of incidence. 

W. G. Golden, Fourier transform infrared reflection-absorption spectroscopy, in Fourier Transform Infrared Spectroscopy Applications to Chemical Systems, J. R. Ferraro and L. J. Basile, Eds., Academic Press, Orlando, IL, 1985, Vol. 4, p. 315. 

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