Photo-electrochemical behaviour of glassy carbon

The photo-electrochemical behaviour of glassy carbon was investigated in th e range of low anodic potentials, both in a supporting electrolyte alone an d in the presence of electron donors (Fe2+, Ru(NH3)(6)(2+)). The amount of the observed photo-current and the shape of the spectral photo-response are shown to be strongly affected by the nature of the effective electron dono r present in the solution. The largest photo-currents, exceeding by far the "dark" currents were observed for the oxidation of Fe2+ ions, known to be catalysed by the C=O groups on the surface of glassy carbon. Only marginal photo-currents, associated with the oxidation of functional groups on the s urface of glassy carbon, were recorded in the supporting electrolyte. (C) 2 001 Published by Elsevier Science B.V.