Journal of Applied Electrochemistry, Vol.32, No.9, 1043-1048, 2002
An in situ spectroelectrochemical Raman investigation of Au electrodeposition and electrodissolution in KAu(CN)(2) solution
Spectroelectrochemical behaviour of CN- on a Au electrode in a KAu(CN)(2) bath at pH 6.3 was studied by in situ confocal Raman spectroscopy. Internal ( CN stretch) and external (Au-CN) CN--related frequencies were investigated under potentiostatic control in a potential interval spanning cathodic and anodic ranges () 1800 to +1200 mV vs Ag/AgCl). Electrochemical behaviour was assessed by cyclic voltammetry. Stark-shifted Au-NC- species are the dominating ones under cathodic polarization. Above the hydrogen evolution potential a Au-H stretch band can also be observed. At open circuit Au-CN-species tend to prevail, while anodic conditions relate to the enhanced formation of Au(CN)(2)(-) and OCN-.