Fig. 7

Mapping of a catalytic reaction at the nanoscale using TERS. a AFM height image showing the distribution of Ag nanoparticles on a glass substrate. b TERS map made using the 1142 cm⁻¹ peak of DMAB from the dotted rectangle marked in (a) indicates the locations where the catalytic reaction takes place. c Near-field spectra from the locations marked in (b) shows the characteristic Raman peaks of the reaction product, DMAB at locations 1, 2 and 3, whereas Raman peaks of only the reactant, pMA, are seen in the spectra from locations 5, 6 and 7. Integration time: 0.5 s. d Intensity profile along the line marked in (b) along with the fitted Gaussian curve shows the 20 nm spatial resolution of the TERS map. Reproduced from [54] with permission from The Royal Society of Chemistry