A field ion microscope — imaging atom probe study of the underpotential deposition of copper on platinum

In the course of studies on the initial stages of electrochemical deposition of alloys, a technique was sought that would determine both the location and the composition of clusters consisting of only a few atoms. The only technique that is capable of sufficient resolution and sensitivity to solve this particular problem, the combination of field ion microscope (FIM) and imaging atom probe (IAP), was utilized. For the first experiments the underpotential deposition of Cu on Pt was studied, since the electrochemical behaviour of this deposition is well known and because Cu should be easy to detect. In addition, Pt gives very sturdy and regular images in the FIM--IAP used for the present studies. 11 ref.--AA