ADSORPTION OF CN** minus ON VARIOUS METAL ELECTRODES AS SEEN BY POLARIZATION MODULATED FT IRRAS.

Abstract

A report is presented on a study of the adsorption of cyanide on a variety of metal electrodes, i. e. Pt, Au, Ag, and Cu and the effect of the electrode potential using the method of PM FT-IRRAS. These measurements are of interest in relation to the role of cyanide as an important ingredient in plating baths of these metals. Results show in general the spectra result from the absorption by surface species as well as by ions dissolved in the solution near the electrode. The bands are due to the CN stretching modes and are in the vicinity of 2100 cm** minus **1. Cyanide surface species are observed on all four metal electrodes whose band positions shift with the voltage. Since the band position of the surface species and the solution species can overlap it is necessary to choose an appropriate cyanide concentration to clearly see the surface species.