Vibrational spectroscopy

Abstract

Fundamental and experimental aspects of infrared spectroscopy techniques are reviewed in connection with their application to the in situ study of the processes taking place at the metal/solution interphase. Advantages and drawbacks of external and internal reflection experiments are discussed in some detail. Then, typical applications are described, with special emphasis on the spectroscopic characterization of adsorbate layers. The feasibility of gaining structural information from the infrared spectra of adsorbed species at different substrates, ranging from adatom–modified single crystal electrodes to nanoparticles is pointed out. New developments are discussed, including the application of step‐scan interferometry to the kinetic study of fast adsorption processes at the electrode surface.

Glycolate adsorption at gold and platinum electrodes: A theoretical and in situ spectroelectrochemical study

“…The detection of strong Au-O stretching bands in the in situ Surface Enhanced Raman Scattering (SERS) spectra [37,38] is consistent with bidentate bonding, which involves the two oxygen atoms of the carboxylate group. As mentioned above, the ATR-SEIRAS experiments provide also information on the potential-dependent water-metal and water-adsorbate interactions [30,39,40]. In this respect, the in situ ATR-SEIRA spectra showed the existence of weak acetate-water interactions in agreement with bidentate bonding of adsorbed acetate and with the hydrophobic character of the methyl group [12,15,16,36,37].…”

“…In situ vibrational spectroscopies, such as infrared and Raman, can provide valuable and complementary information on some microscopic aspects of adsorption processes such as preferred adsorption sites, bonding geometry and molecular orientation with respect to the solid surface, as well as on the adsorbate-metal and adsorbate-adsorbate interactions [28][29][30][31]. This information relies on the correct interpretation of the spectra of adsorbed species on metal electrodes.…”

“…It has been also shown, that this kind of films presents also noticeable SERS activity [37,38]. The ATR-SEIRAS [30,39,40] and SERS [29] techniques provide a significant enhancement of the infrared absorption and Raman scattering by adsorbed species, allowing the detection of weakly absorbing modes and/or low coverage intermediates. The theoretical vibrational frequencies and intensities of adsorbed species at Au(1 1 1) clusters will be calculated in order to assign the infrared and Raman bands to vibrational modes and different adsorption geometries [32].…”

Influence of the CO Adsorption Environment on Its Reactivity with (111) Terrace Sites in Stepped Pt Electrodes under Alkaline Media

“…The spectroelectrchemical cell was equipped with a CaF2 prism beveled at 60º. [29][30] One hundred interferograms with a resolution of 8 cm -1 were collected for each spectrum using p-polarized light. Spectra was acquired in a 25 mV sampling interval from 0.05 V to 0.70 V.…”

On the electrochemical behavior of formamidine disulfide on gold electrodes in acid media

“…The spectroelectrochemical cells used in this work are equipped with a prismatic window (Si or CaF 2 , for the internal and external reflection experiments, respectively) beveled at 60° [58,59]. In situ infrared experiments were carried out using a Nexus 8700 (Thermo Scientific) spectrometer equipped with a MCT-A detector.…”