Work function and UPS study of Au and O on Re

Abstract

The influences of O and Au on the electron energy distribution curves (EDC's) and work function on Re polycrystalline ribbons have been measured using ultraviolet photoelectron spectroscopy (UPS) and contact potential difference (CPD). Surface coverages of both Au and O were found to increase the work function of the Re filament. The variation in work function initially increased with Au coverage and then saturated, as described by the Topping model, producing values for the dipole moment of (-7 ±- 1.9)x10 -31 C m and polarizability of 7 ±- 2.1 Å 3. The work function increased linearly with O coverage and could be fit by either the Nordheim or Topping equations producing a dipole moment of -10.7 x 10 -31 C m. The EDC's showed the filling of a state ∼6 eV below the Fermi level for both submomolayer Au and O coverages.