A core-level photoemission spectroscopy study of the formation of surface alloy Cu/Pt(111): comparison with Pt/Cu(111)

Abstract

We present first results on the formation of a surface alloy starting from the deposition of thin Cu films on a Pt(111) substrate. Annealing at 300°C leads to the kinetic blocking of the dissolution process. We have used synchrotron radiation to measure the Pt4f7/2 core-level shifts due to the alloying process. We estimate the Pt concentration in the surface layer to be 50%. These results are compared to previous work on the Pt/Cu(111) system which demonstrated the formation of a Cu3Pt surface alloy. The influence of surface segregation and bulk alloying in driving the formation of a surface-alloy phase during dissolution is discussed.