Local monitoring of surface chemistry with Raman spectroscopy

The efficiency of Raman scattering from molecules in some nano-resonators can increase by many orders of magnitude. Sometimes, in Raman measurements carried out with such resonators, it is possible to record a spectrum from only a few (or even a single) molecules. In this contribution, we show that resonator-enhanced Raman scattering is very useful for analysis of the electrochemically formed carbon. Carbon material has been formed on the surface of the copper-modified silver electrode during the electrochemical reduction of CO2. The Raman spectra measured were often from only a few carbon clusters. By the analysis of a large series of such spectra, we managed to identify large graphite-like rings and polyenes with various lengths. Some other applications of resonator-enhanced Raman scattering to local characterisation of electrode surfaces (e.g. studies of CO adsorption on gold) are also presented.