The V₂O₅ Surface Phonon Spectrum

V₂O₅ is a layered semiconducting oxide, which is used as a catalyst for the partial oxidation of hydrocarbons. In view of its catalytic applications, the vibrational properties of the (001) surface were examined by means of HREELS, a technique which is uniquely sensitive to the first layers' characteristics. On a clean single crystal, surface phonons corresponding to IR active vibrational modes are detected. The layered structure of single crystal V₂O₅ allowed for the creation of a clean (001) surface by UHV cleavage. The loss spectrum was recorded using a SEDRA spectrometer, providing a highly monochromatic, low energy primary electron beam. Hence, with a minimum of surface interference, a detailed loss spectrum with FWHM of 2.87 meV was obtained.