Optically Transparent Thin-Layer Cell OTTLE

Optically Transparent Thin-Layer Cell (OTTLE)... 

The other popular approach to in situ spectroelectrochemistry is based on the use of an OTE electrode in a thin-layer, optically transparent thin layer electrode (OTTLE), cell. A schematic representation of one design of OTTLE cell is shown in Figure 2.105. 

Figure 2.105 Optically transparent thin layer electrochemical (OTTLE) cell. A = PTFE cell body, B = 13 x 2 mm window, (C and E) = PTFE spacers, D = gold minigrid electrode, F = 25 mm window, G = pressure plate, H = gold working electrode contact, 1 = reference electrode compartment, J = silver wire, K = auxiliary electrode and L = solution presaturator. From Ranjith...

A vacuum spectroelectrochemical cell that also contains an optically transparent thin-layer electrode (OTTLE) is shown in Figures 18.16 and 18.17. The cell can function either as a spectroelectrochemical cell employing an OTTLE or as an electrochemical cell for voltammetric measurements. This low-volume cell is useful for UV/Vis spectral studies in nonaqueous solvents when the reduction product is sensitive to traces of molecular oxygen present in the solvent. The cell is physically small enough to fit inside the sample compartment of the spectrophotometer. The performance of such a cell was evaluated from visible spectroscopy and coulometry of methyl viologen in propylene carbonate [45]. 

Figure 18.16 Vacuum electrochemical cells (A) vacuum spectroelectrochemical cell that contains an optically transparent thin-layer electrode (OTTLE) and (B) electrochemical cell assembly. [From Ref. 45, with permission.]...

Other spectroscopic techniques that have been used with electrochemistry to probe nanoparticles include electronic and vibrational spectroscopies. The spec-troelectrochemistry of nanosized silver particles based on their interaction with planar electrodes has been studied recently [146] using optically transparent thin layer electrodes (OTTLE). Colloidal silver shows a surface plasmon resonance absorption at 400 nm corresponding to 0.15 V vs. Ag/AgCl. This value blue shifts to 392 nm when an Au mesh electrode in the presence of Ag colloid is polarized to —0.6 V (figure 20.12). The absorption spectrum is reported to be quite reproducible and reversible. This indicates that the electron transfer occurs between the colloidal particles and a macroelectrode and vice versa. The kinetics of electron transfer is followed by monitoring the absorbance as a function of time. The use of an OTTLE cell ensures that the absorbance is due to all the particles in the cell between the cell walls and the electrode. The distance over which the silver particles will diffuse has been calculated to be 80 pm in 150 s, using a diffusion coef-... 

Fe -"Fe -") species (NC)4Fe(p-bmtz)Fe(CN)4r 6 ( c= 10 in CH3CN/O.I M Bu4NPF6) from an experiment with an optically transparent thin-layer electrolysis (OTTLE) cell with Pt gauze working electrode is only one form of graphical representation, difference spectra or three-dimensional plots are also being used. ... 

The metal-metal interactions in the polymer network were investigated by controlled potential electrolysis with the aid of an optically transparent thin-layer electrochemistry (OTTLE) cell. In the visible/near-IR spectrum of the fully reduced deep-red/orange gel the lowest-energy visible band is assigned to a d-d transition. Upon oxidation, two new absorption peaks emerge one at 640 nm is due to a li-gand-to-metal charge-transfer (LMCT) of the ferrocenium moiety, whereas the... 

The electronic absorption data for the polyaammineruthenium dinuclear complexes were obtained by spectroelectrochemical studies, using an optically transparent, thin-layer electrochemical (OTTLE) cell. It is important that the effect of electrochemical titration on the... 

Figure 1 shows the structure of an optically transparent thin-layer electrochemical (OTTLE) cell [8]. 

The species C60 (n=0,1,2,3) have been electrogenerated in 0.5M Bu 4NBF4 in CH2CI2 solution at -60°C The UV and near-IR Spectra were recorded (in the range 5000cm 1 to 50000cm ) in an Optically Transparent Thin Layer Electrochemical (OTTLE) cell. 

Haiti F, Luyten H, Nieuwcmhuis HA, Schoemaker GC (1994) A versatile ciyostated optically transparent thin-layer electrochemical (OTTLE) cell for variable-temperature UV-vis/IR spectroelectrochemical studies. Appl Spectr48 1522... 

ABTS + production has been described by using thin-layer spectroelectrochemistry [46]. Fifty microliters of ABTS in 0.1 M acetate buffer solution (pH 5) was oxidized in a quartz flat cell (0.1 cm width) containing an optical transparent thin-layer electrode (OTTLE system). The radical formation was measured with a potential scan from 0.65 to 0.70 V and returned to 0.65 V at the scan rate of 0.05 mV s . The reactions were monitored spectrophotometrically every 30 s. Figure 31.11 shows the 3D plots obtained for spectral changes during ABTS electrolysis at different intervals. At the beginning, with ABTS as the sole species, two peaks were observed (A = 214 nm, A.2 = 340 nm), but as the... 

Figure 1 shows absorbance spectra, for a series of applied potentials, recorded in an electrochemical cell employing an optically transparent thin-layer electrode (OTTLE). Curve a was recorded after application of -1-0.800 V vs saturated calomel electrode (SCE), which under thin-layer electrode... 

Figure 1 Schematic diagram of spectroelectrochemical techniques at an optically transparent electrode (OTE). (A) Transmission spectroelectrochemistry (B) transmission spectro-electrochemistry with an optically transparent thin-layer electrode (OTTLE) cell (C) internal reflection spectroscopy (IRS). Reprinted by courtesy of Marcel Dekker, Inc. from Heineman WR, Hawkridge FM and Blount HN (1984) Spectroelectrochemistry at optically transparent electrodes. II. Electrodes under thin-layer and semi-infinite diffusion conditions and indirect coulometric titrations. In Bard AJ (ed) Electroanalytical Chemistry. A Series of Advances, Vol 13, pp 1-113. New York Marcel-Dekker.

Figure 5 Optically transparent thin-layer electrode (OTTLE) cell (A) front view (B) side view, (a), Point of suction application to change solution (b) Teflon tape spacers (c) microscope slides (1x3 in.) (d) solution (e) transparent gold minigrid electrode (f) optical path of spectrometer (g) reference and counter electrodes (h) solution cup. Epoxy resin holds the cell together. Reprinted with permission from DeAngelis TP and Heineman WR (1976) Journal of Chemical Education 53 594-597. 1976 American Chemical Society.

Method Abs, chemical reduction, monitored by absorption spectroscopy CD, chemical reduction, monitored by CD spectroscopy CD/OTTLE, electrochemical reduction using an optically transparent thin layer (OTTLE) cell, monitored by CD spectroscopy CV, cyclic voltammetry EPR, chemical reduction, monitored by EPR. 

The question of whether electrons added to a complex ion become localized or delocalized is important, not only for the type of complex mentioned above, but also for much wider ranges of complexes. For such studies the use of an OTTLE (optically transparent thin layer electrochemical) cell is most appropriate... 

The optically transparent thin-layer electrochemical (or OTTLE) cell has caught on to the greatest extent for UV-vis spectroelectrochemistry (Figure l).1-3 The OTTLE also offers a way to measure both the redox potential and the n-value without requiring knowledge of the electron... 

Figure 3 Spectroelectrochemical cell configurations (1) transmission cell with optically transparent electrode (OTE) (2) transmission optically transparent thin layer electrode cell (OTTLE) with OTE (3) sandwich OTTLE cell with minigrid or reticulated carbon (RVC) electrode (4) long optical path-length cell (LOPTC) with light parallel to electrode surface (5) double transmission reflection cell (6) internal...

OTTLE cell Optically transparent thin-layer electrochemical cell... 

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