In-situ SERS of dissociative adsorption and oxidation of ethanol on roughed platinum electrodes

Abstract

The behaviors of adsorption and oxidation of ethanol on a roughened platinum electrode with high SERS activity were studied by using cyclic voltammetry and in-situ surface enhanced Raman spectroscopy, surface Raman spectra of dissociative adsorption of ethanol on Pt electrode in acid medium have been obtained. The results show that ethanol can be dissociated on the Pt surface in acid medium to produce poisoning intermediate CO, which suppresses the further oxidation of ethanol, and some informations of Pt - C and Pt - C - Pt stretching vibration from linearly-adsorbed and bridged-adsorbed CO located in low frequency were obtained, respectively. The investigation also shows that the electro-oxidtion of ethanol on the roughened platinum was a diffuse-controlled reaction in sulfuric acid. By correlating the in- situ SERS data with the electrochemical data, it was found that the oxidation of ethanol proceeded via the parallel mechanism.