Spectroscopy FTIR reflection

Reaction products can also be identified by in situ infrared reflectance spectroscopy (Fourier transform infrared reflectance spectroscopy, FTIRS) used as single potential alteration infrared reflectance spectroscopy (SPAIRS). This method is suitable not only for obtaining information on adsorbed products (see below), but also for observing infrared (IR) absorption bands due to the products immediately after their formation in the vicinity of the electrode surface. It is thus easy to follow the production of CO2 versus the oxidation potential and to compare the behavior of different electrocatalysts. 

Kunimatsu K, Seki H, Golden WG, Gordon JG II, Philpott MR. 1985b. Electrode/electrolyte interface study using polarization modulated FTIR reflection-adsorption spectroscopy. Surf Sci 158 596-608. 

Fourier transform Infrared spectroscopy has been shown to be an excellent tool for surface and Interface studies (.2), In this paper, the application of reflection/absorption Fourier transform Infrared spectroscopy (FTIR-RA) for studying the degradation of amine-cured epoxy and polybutadiene coatings on cold-rolled steel after exposure to a warm, humid environment is reported. 

At potentials higher than 0.6 V vs RHE, the dissociative adsorption of water occurs on platinum, providing -OH adsorbed species, able to oxidize further the adsorption residues of ethanol. Then, oxidation of adsorbed CO species occurs as was shown by FTIR reflectance spectroscopy and CO stripping experiments [36] ... 

Andrievsky GV, Klochkov VK, Bordyuh AB, Dovbeshko G1 (2002) Comparative analysis of two aqueous-colloidal solutions of C- 60 fuUerene with help of FTIR reflectance and UV-Vis spectroscopy. Chem Phys Lett 364 8-17... 

A recent example of the application of in situ FTIR reflectance spectroscopy to modified electrodes can be found in the work of Korzeniewski and her group [54] on Pt electrodes coated with films of the polymer polyaniline. Figure 13.6 shows the reflectance spectrum (in AR/R units) of a polyaniline film-coated electrode as a function of applied potential. As the film becomes more oxidized, the band at 1320 cm-1 is shifted to higher energies, a result consistent with an increasing C-N bond strength upon oxidation [54]. The interac-... 

In other studies Allara (27) used FTIR reflection to study the interaction of the oxide film of aluminum with acetic acid in which th aluminum acetate carbonyl stretch peak was found at 1590 cm- > in excellent agreement with the 1589 cm-1 peak determined by inelastic electron tunnelling spectroscopy (IETS), another modern technique for vibrational spectra at metal interfaces. The spectra of acetic acid adsorbed on copper oxide or indium,oxide were about the same. 

FTIR reflectance and transmission spectroscopy is used for analysis of thin films. Nevertheless, due to the high absorptivities of mid-IR bands, the film thickness must be limited (up to 100 pm, depending on the specific bands chosen) in order to perform an accurate qualitative analysis. Other IR methods, such as attenuated total reflectance (ATR) and photoacoustic methods provide IR spectra of thick material, because they penetrate a very thin layer at the surface of a sample. However, is important to point out that the effective pathlength for the ATR and the photo-acoustic methods depends on the refractive index and thermal diffusivity, respectively. Therefore, the use of these techniques for the quantitative analysis of non-homo-geneous materials can be difficult. 

The introduction of Fourier Transform Infrared Spectroscopy (FTIR) brought along a number of typical solid sample techniques. DRIFTS (Diffuse Reflectance Fourier Transform Infrared Spectroscopy) is probably most commonly known. Another technique, developed specifically for measuring solid, opaque samples is PAS (Photo Acoustic Spectroscopy). This accessory is less known, probably due to its high cost and its rather difficult modus operandi. 

Palladium nanoparticles (nm-Pd) were synthesized by ship-in-a-bottle technique in supercages of NaA zeolite. The behaviors of electrodes of thin film of nm-Pd accommodated in NaA zeolite were characterized by cyclic voltammetry. The results illustrated that the nm-Pd possess particular properties for hydrogen reaction, i.e. in contrast to hydrogen absorption on massive palladium electrode, the surface processes of hydrogen adsorption-desorption become the dominant reaction on electrodes of thin film of nm-Pd. The processes of adsorption and desorption of carbon monoxide on the electrodes were studied using in situ electrochemical FTIR reflection spectroscopy. It has been revealed that in comparison with CO adsorbed on a massive Pd electrode, the IR absorption of CO adsorbed on nm-Pd particles accommodated in NaA zeolite has been enhanced to about 36 times. 

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