Single Potential Infrared

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. 

Corrigan DS, Weaver MJ. 1988. Mechanisms of formic acid, methanol, and carbon monoxide electrooxidation at platinum as examined by single potential alteration infrared spectroscopy. J Electroanal Chem 241 143-162. 

Figure 11.10 Single potential alteration infrared (SPAIR) spectra of the species coming from ethanol adsorption and oxidation on a Pt-Sn (90 10)/C electrode (0.1 M HCIO4 + O.IM C2H5OH, 25 °C). The reference spectrum was taken at 50 mV vs. RHE.

On the other hand, imique physical properties and potential applications of nanoscaled lanthanide-doped LaFa have been discussed in many reports. For instance, van Veggel et al. reported the bright white light through up-conversion of a single near-infrared source by thin film of LaFaiYb, Eu /Er /Tm NPs (Figure 65) (Sivakumar et al., 2005). And the silica films with (Er +, Nd +, and Ho ) doped LaFs NPs possessed the visible white luminescence (Sudarsan et al., 2005). 

In situ IR spectra were recorded using, either the Single Potential Alteration Iirfrared Reflectance Spectroscopy (SPAIRS), also called Linear Potential Sweep-Fourier Transform Infrared Reflectance Spectroscopy (LPS-FTIRS), or the Subtractively Normalized Interfacial Fourier Transform Infrared Reflectance Spectroscopy (SNIFTIRS). ... 

We have studied the Jahn-Teller effect in this phase by MIR spectroscopy [31, 70]. The Ti (4) mode shows a twofold splitting and modes that are silent in Ceo appear, indicating a D3 or T>sd distortion of the molecule (Fig. 10). As the C o ions are rotating in this phase [73,74], the distortion cannot be caused by the crystal field but must be due to the molecular Jahn-Teller effect. As there is no crystal field to lock the Cgo into a single potential well, the distortion is dynamic, with the rate of pseudorotation smaller than that of the infrared measurement. 

The same method is sometimes called PDIRS (for potential difference infrared spectoscopy) or SPAIRS (for single potential alteration infrared spectroscopy). 

LPSIRS Linear Potential Sweep Infra-Red Spectroscopy SPAIRS Single Potential Alteration Infra-Red Spectroscopy PDIRS Potential Difference Infrared Spectroscopy EMIRS Electrochemically Modulated Infra-Red Spectroscopy SERS Surface Enhanced Raman Scattering (Surface Enhanced Raman Spectroscopy)... 

SPAIR(S) Single potential alteration infrared (spectroscopy)... 

Ag-coated Ge hemicylindrical prism with a 0.6 s data acquisition time by exploiting SEIRAS. Spectra were collected during the acquisition of a cyclic voltammogram, recorded at a scan rate of 10mVs this experimental protocol was earlier termed SPAIRS (single potential alteration infrared spectroscopy) by Weaver and coworkers [121] (see Sect. 3.5.4.1.3 in the following text). 

Surface-extended X-ray absorption fine structure (analysis) spectroscopy Sum frequency generation Second harmonic generation Surface ionization Secondary ion mass spectroscopy Subtractively normalized interfacial Fourier transform infrared spectroscopy Single potential alteration infrared (spectroscopy)... 

The potential energy surface [47] for this reaction (Fig. 5) shows many potentially competitive pathways, labeled A-F, leading to the two most exothermic product channels. Many of these pathways can be isotopically separated by reaction of 02 with HCCO in normal abundance, as diagramed in Fig. 5. Zou and Osbom used time-resolved Fourier transform emission spectroscopy to detect the CO and CO2 products of this reaction [47]. Rotationally resolved infrared (IR) spectroscopy can easily identify all the possible isotopologs. For example. Fig. 6 shows a single... 

Structural effect was confirmed by in situ infrared spectroscopy which showed a high coverage of adsorbed CO on a R( 110) plane conversely, on the other single-crystal planes, a distribution of different species is clearly visible. Further, strong lateral interactions between the different adsorbed species on Pt(lOO) lead to very low activity of this electrode at low potentials. ... 

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