CO, stripping voltammograms

Lopez-Cudero A, Cuesta A, Gutierrez C. 2005. Potential dependence of the saturation CO coverage of Pt electrodes The origin of the pre-peak in CO-stripping voltammograms. Part 1 Pt(lll). J Electroanal Chem 579 1-12. 

Figure 10.5 CO-stripping voltammograms (sweep rate 0.10 V s ) at pure Pt and stabilized Pt5gCo42 in 0.1 M HCIO4, and PtgoRu4o in 0.05 M H2SO4 at room temperature. The CO pre-adsorption was performed in CO-saturated solution at 0.075 V for 5 minutes. (From Wakisaka et al. [2006], reproduced by permission of the American Chemical Society.)...

Figure 12.5 CO stripping voltammogram with a CO- tee 0.1 M H2SO4 electrolyte. Compare the data in Fig. 12.4 the CO oxidation region begins at V = 0.43 V. After CO stripping, hydrogen adsorption/desorption peaks and the beginning of the Pt oxidation range are shown.

The electric current response, in terms of peak position, multiplicity and intensity, of CO stripping voltammograms recorded on supported platinum nanoparticles is heavily discussed in the literature. The electro-oxidation of CO is a complex reaction, as it is evidenced by the multiplicity of the voltammetric oxidation peaks which are recorded in a relatively narrow potential range. This multiplicity of peak was also observed for continuous bulk CO oxidation and studied using electrochemical and UV-visible potential modulated reflectance spectroscopy, and was shown to be dependent on the CO admission potential. For example, the vol-tammogram of CO stripping presented in Fig. 2, recorded at a Pt (40 wt %) /C catalyst prepared via the water in oil method,displays at least three oxidation peaks a prepeak centered close to 0.6 V, a second peak well defined close to 0.755 V and a third one close to 0.820 V vs. RHE. Several models were proposed to explain the multiplicity of peak. 

Figure 19. CO stripping voltammograms of Ru/Au(lll) (solid line) and the baselines obtained on CO free surfaces (dotted line) obtained in 0.1 M FI2 SO4 for (a) a multilayer deposit (b) a saturated monolayer (0.85 ML coverage) (c) a submonolayer deposit (0.15 ML coverage). Reprinted from Ref.12 with permission from Elsevier.

Figure 20. Cyclic voltammetry of Ru/Au(lll) in 0.1 M H2SO4 after Ru had been spontaneously deposited from 1 mM RUCI3 in 0.1 M HCIO4 for 3 min (dotted line) and CO stripping voltammogram of the same surface, obtained after 5-min CO adsorption at —0.25 V and subsequent purging of the solution with argon (solid line). Reprinted from Ref.9 with permission from Elsevier.

Figure 2S. CO stripping voltammograms obtained after 12 hrs of methanol adsorption onto commercial Pt-black and Pt/Ru alloy nanoparticles. Scan rate was 10 mv/min. The surface areas are normalized."...

Figure 9.15 CO -stripping voltammograms of Pt/C catalysts prepared over treated (Pt3, Pt4, Pt5) and untreated carbons (Ptl, Pt2, Pt6). ...

Figure 5.11 CO-stripping voltammograms on 47 wt% Pl/C catalyst-coated glassy carbon electrode, recorded in N2-saturated 0.1 M HCIO4. Potential scan rate ...

FIGURE 12.3 A CO-stripping voltammogram on 47 wt.% Pt/C catalyst-coated GC electrode, recorded in Na-saturated 0.1 M HCIO4. Potential scan rate 20mVs Pt/C catalyst loading 48 pg cm [18]. (For color version of this figure, the reader is referred to the online version of this book.)... 

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