Identification of Surface Vibrations on Clean and Oxygen Covered Pt(111) Surfaces with High Resolution Electron Energy Loss Spectroscopy (EELS)

Clean and oxygen covered {111} recrystallized Pt surfaces were studied by EELS after surface preparation at 150≤T≤1650K. The clean surface shows Stokes as well as anti-Stokes lines of surface phonons at ± 195−1. Adsorption of small amounts of (<10−2 monolayers) of O2 or H2 leads to substrate-derived phonon losses at ±380cm−1. Oxygen exposure at different pressures, times and temperatures leads to atomic and/or molecular adsorption as well as oxide-related features which have been identified by EELS.