CYANIDE ADSORBED AS A MONOLAYER AT THE LOW-INDEX SURFACE PLANES OF PLATINUM METAL-ELECTRODES - AN IN-SITU STUDY BY INFRARED-SPECTROSCOPY

We report the infrared spectral features for cyanide adsorbed at the l ow-index surface planes of platinum electrodes. A single vibrational f eature is observed for cyanide at Pt(111), and the position and potent ial dependence of the band coincide with what has been reported for th e linear surface cyanide species at polycrystalline silver and gold el ectrodes. Spectral features associated with the [Pt(CN)2]2- complex ap pear in experiments which probe cyanide adsorption at Pt(100) and Pt(1 10), indicating the likelihood of surface disordering under these expe rimental conditions. Similarly, dissolution of the platinum surface to form the [Pt(CN)2]2- complex is suggested to explain the low-pH behav ior observed for cyanide at polycrystalline platinum electrodes.