Confocal Raman spectroelectrochemistry

A very elegant approach overcoming this problem has been proposed based on a channel flow cell geometry with downstream detection (Fig. II.6.2d). The potential of the electrode is stepped during steady-state flow of the solution across the electrode. A downstream UVA is detector system is then employed to measure the time dependence of the concentration profile formation at the electrode surface. A computer program is employed to relate the time-dependent absorbance signal to the concentration profile of reactant and product at the electrode surface. Alternatively, direct measurement of the concentration profiles at the electrode surface has also been reported based on confocal Raman spectroelectrochemistry [16]. 

Figure 14.28 Confocal Raman spectroelectrochemistry of a thin surface layer of solid films of HQBpt (inset) on a glassy carbon electrode (A) at open circuit potential, (B) at +0.700 V. The supporting electrolyte was aqueous 0.1 M LiC104. Reprinted with permission from reference (71). Copyright 2001, American Chemical Society.

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