You are here: Home :: Area NEM :: Chemistry :: Physical chemistry

C. E. Täubert, Marcel Petri, Dieter M. Kolb

On a New Phase Transition in the Cu/Au(111)/H₂SO₄ System

Keywords: Au(111), Cu, Cyclic voltammetry, Phase transition, Underpotential Deposition

A new pair of current spikes has been found in the cyclic voltammogram of Au(111) in an acidic copper sulphate solution, indicative of a phase transition in the Cu adlayer. The spike potential is well inside the bulk deposition region and hence, the new feature can be observed only at low Cu⁺⁺ concentration, when bulk deposition is slow. The charge under the spike correlates linearly with extent of the (√ 3 × √ 3 )R30º structure, up to 40μCcm^-2 for the fully developed superstructure. The spike potential shifts with the sulphate concentration and hence, this feature is assigned to the desorption of sulphate from the well-known honey comb structure of the Cu upd layer.

Zeitschrift für Physikalische Chemie, Oldenbourg Wissenschaftsverlag

Print ISSN: 0942-9352
Volume: 221, 11/2007
Pages: 1493 - 1498

Show full article (external site)

Show all available items of this journal

 

Area NEM