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Separation of time-resolved phenomena in surface-enhanced Raman scattering of the photocatalytic reduction of p-nitrothiophenol.

van Schrojenstein Lantman EM, de Peinder P, Mank AJ, Weckhuysen BM - Chemphyschem (2014)

Bottom Line: We show that it is possible to study effects that occur on different time scales independently without data reduction using the photocatalytic reduction of p-nitrothiophenol as a showcase system.Using this approach a better description of the nanoscale reaction kinetics becomes available, while the short-term variations can be examined separately to examine reorientation and/or diffusion effects.Now such events can be easily separated from the bulk conversion process by making use of this chemometric method.

View Article: PubMed Central - PubMed

Affiliation: Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht (The Netherlands).

No MeSH data available.


Related in: MedlinePlus

MCR model of all spectra belonging to the bulk reaction. In a) the two calculated components are shown. Component 1 (green) represents 27 % of the calculated model, component 2 (blue) represents 70 % of the calculated model, with a total of 97 % variance explained. b) Shows the score of components 1 and 2 in time. c) All input spectra for the MCR model and d) the spectral residuals that are not explained by the MCR components. These two figures are shown on the same intensity scale for comparison.
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fig5: MCR model of all spectra belonging to the bulk reaction. In a) the two calculated components are shown. Component 1 (green) represents 27 % of the calculated model, component 2 (blue) represents 70 % of the calculated model, with a total of 97 % variance explained. b) Shows the score of components 1 and 2 in time. c) All input spectra for the MCR model and d) the spectral residuals that are not explained by the MCR components. These two figures are shown on the same intensity scale for comparison.

Mentions: Figure 4 c shows the breakdown of the full set into the different sets of spectra. Black spectra fall within the Q‐residual criterion and describe the reaction. Green spectra do not meet up to the Q‐residual criterion, but make it through the time filter. They are likely an orientation effect due to changes in the monolayer, and are included in the analysis of the bulk reaction in Figure 5. Red spectra are set aside and are analyzed in Figure 6. The spectral pattern of these three sets is quite clear. With respect to the black spectra, the green spectra are only small deviations. In contrast, the red spectra show much more vibrational bands than observed in the black spectra.


Separation of time-resolved phenomena in surface-enhanced Raman scattering of the photocatalytic reduction of p-nitrothiophenol.

van Schrojenstein Lantman EM, de Peinder P, Mank AJ, Weckhuysen BM - Chemphyschem (2014)

MCR model of all spectra belonging to the bulk reaction. In a) the two calculated components are shown. Component 1 (green) represents 27 % of the calculated model, component 2 (blue) represents 70 % of the calculated model, with a total of 97 % variance explained. b) Shows the score of components 1 and 2 in time. c) All input spectra for the MCR model and d) the spectral residuals that are not explained by the MCR components. These two figures are shown on the same intensity scale for comparison.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4834609&req=5

fig5: MCR model of all spectra belonging to the bulk reaction. In a) the two calculated components are shown. Component 1 (green) represents 27 % of the calculated model, component 2 (blue) represents 70 % of the calculated model, with a total of 97 % variance explained. b) Shows the score of components 1 and 2 in time. c) All input spectra for the MCR model and d) the spectral residuals that are not explained by the MCR components. These two figures are shown on the same intensity scale for comparison.
Mentions: Figure 4 c shows the breakdown of the full set into the different sets of spectra. Black spectra fall within the Q‐residual criterion and describe the reaction. Green spectra do not meet up to the Q‐residual criterion, but make it through the time filter. They are likely an orientation effect due to changes in the monolayer, and are included in the analysis of the bulk reaction in Figure 5. Red spectra are set aside and are analyzed in Figure 6. The spectral pattern of these three sets is quite clear. With respect to the black spectra, the green spectra are only small deviations. In contrast, the red spectra show much more vibrational bands than observed in the black spectra.

Bottom Line: We show that it is possible to study effects that occur on different time scales independently without data reduction using the photocatalytic reduction of p-nitrothiophenol as a showcase system.Using this approach a better description of the nanoscale reaction kinetics becomes available, while the short-term variations can be examined separately to examine reorientation and/or diffusion effects.Now such events can be easily separated from the bulk conversion process by making use of this chemometric method.

View Article: PubMed Central - PubMed

Affiliation: Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht (The Netherlands).

No MeSH data available.


Related in: MedlinePlus