Photoemission of adsorbed xenon on Pt xNi 1− x(111) single crystal alloy surfaces

Abstract

Photoemission of adsorbed xenon and work function measurements have been performed on three fcc, (111) oriented, PtNi single crystal alloys showing a strong platinum surface segregation. For Pt-rich alloys, the first layer has been found a quasi-homogeneous layer but different from a pure Pt(111) surface. No platinum islands have been observed. The local and the macroscopic work function are nearly the same and do not change linearly with the alloy composition but remain nearly constant and close to 5.4 eV, a value significantly lower than that on a pure Pt(111) face (5.95 eV).