Photoemission studies on Pt foil implanted by carbon atoms accelerated in a Van de Graaff generator: nature of the interaction between Pt and carbon

X-ray and UV-photoelectron spectroscopies have been applied to study Pt foils implanted with carbon atoms of fluxes in the range of 1015 to 1018 atoms/cm2 accelerated by a 100 keV Van de Graaff generator. Core level Pt 4f and C 1s X-ray photoelectron spectra do not indicate any charge transfer between carbon and Pt. MgKα and He (I) excited valence band spectra, however, allow us to conclude the presence of a weak interaction between carbon and Pt. At high flux, small, isolated Pt fragments are segregated and embedded into the carbon overlayer and this is indicated by a change of the Fermi edge in the PtC system. On the other hand, at low flux larger Pt crystallites are exposed to the surface and in addition to graphite like carbon, weak electronic interaction can be proved based on the valence band intensities near to the Fermi level.