Analyzing the adsorption behavior of thiocyanide on pure Pt and Ni electrode surfaces by confocal microprobe Raman spectroscopy

Thiocyanide ion adsorption on Pt and Ni electrode surfaces was investigated by confocal Raman microscopy. The effects on the adsorption behavior of SC N- by the electrolyte anion, concentration and applied potential were studi ed. The potential has a significant effect on the frequency shift of SCN- a s a result of the electrochemical Stark effect. The adsorbability of the el ectrolyte anion has a significant influence on the surface Raman intensity of SCN-; the intensity follows the order Cl- <ClO4- <F-. It can be explaine d in terms of competitive adsorption between the SCN- and the anion. It has been shown that surface Raman spectroscopy can be a sensitive tool for the in-situ analysis of the surface species and its configuration, such as sur face complexes and films on transition metal electrodes.