Cover Picture: Separation of Time-Resolved Phenomena in Surface-Enhanced Raman Scattering of the Photocatalytic Reduction of p-Nitrothiophenol (ChemPhysChem 3/2015)

• Published in: Chemphyschem Vol. 16; no. 3; p. 485
• Main Authors: van Schrojenstein Lantman, E. M., de Peinder, P., Mank, A. J. G., Weckhuysen, B. M.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 23.02.2015; Wiley Subscription Services, Inc
• Subjects: chemometrics; heterogeneous catalysis; Kinetics; Raman spectroscopy; self-assembly; Spectrum analysis; surface-enhanced Raman scattering
• ISSN: 1439-4235; 1439-7641
• DOI: 10.1002/cphc.201402775

The analysis of nanoscale processes is challenging, as the measurement volume is linked to a discrete number of molecules, ruling out any ensemble averaging. Raman spectroscopy allows chemical changes to be monitored, but is not very sensitive when applied directly. Surface-enhanced Raman spectroscopy can be used for studying reaction kinetics, but adds additional variability in the signal as the enhancement factor is not the same for every location. On p. 547, B. M. Weckhuysen et al. describe a chemometric method that separates reaction kinetics from short-term variability. It is possible to study effects that occur on different time scales independently without data reduction. By using this approach a better description of the nanoscale reaction kinetics becomes available, and the short-term variations can be studied separately to examine reorientation and diffusion effects. It may even be possible to identify reaction intermediates through this approach.