High temperature growth of Pt on the Rh(111) surface

The epitaxial growth of Pt on the Rh(111) surface at 700 K was studied with AES, UPS, ISS and STM. From AES and ISS measurements a 2D growth mode is c oncluded at this substrate temperature. The morphology of the surface is st udied by photoemission spectra of adsorbed Xe (PAX) and STM. A disperse dis tribution of the Pt atoms is suggested by PAX and is consistent with an inc orporation of these atoms into the first substrate layer. Atomically and ch emically resolved STM measurements confirm these conclusions. The interacti on of CO with the surface alloy is investigated by UPS. The GO-induced feat ures in UP spectra show significant differences in the peak positions and s hape between the clean substrate and the surface precovered with different amounts of Pt. The CO induced emissions are, thus, used for a quantitative titration of Pt on the Rh surface. (C) 1999 Elsevier Science B.V. All right s reserved.