Photoelectron Spectroscopy

The electronic states of adsorption of phenol on TiO2 (110) is investigated by Ultraviolet Photoelectron Spectroscopy (UPS) as a well-defined model for environmentally persistent free radicals. The radicals, airborne ultrafine particles generated in combustion reactions, have effects on human illness such as cardiopulmonary disease.  A clean TiO2 (110) surface with a small amount of oxygen vacancies was prepared by sputtering with Ne-ion and annealing in the UHV chamber.  The phenol dosage was facilitated by introducing sublimated phenol vapor into the UHV systems through a leak valve.  The figure below shows the photoelectron spectra of both clean and 100 L phenol exposed TiO2 (110) surface.  Upon phenol adsorption new electronic features appeared (b in the figure) on the valence band at binding energies of 2.4 eV, 10.7 eV, 13.5 eV and 16.7 eV.  The result infers that phenol adsorbs on the surface of TiO2 with occupying the oxygen vacancy sites and oxidizing metal ion (Ti).

 

UPS

 

View research examples done by LSU Physics Surface Science group at www.surfaces.lsu.edu/ 

 

Supported beamlines:  5m-TGM Beamline for UPS, ARUPS, XPS Click for Beamline Information

VLSPGM Beamline for soft X-ray photoemission   Click for Beamline Information

Research/Technical Contact: Orhan Kizilkaya