Gold nanoparticles adsorbed on tungsten: effect of sodium atom deposition and heating

We studied the electronic structure of gold nanoparticles deposited on a tungsten surface before and after the deposition of sodium atoms with subsequent heating at $T$ = 630 K by in situ photoelectron spectroscopy in ultrahigh vacuum. The photoemission spectra from the valence band and core levels of Au 4$f$ and Na 2$p$ were studied upon synchrotron excitation in the photon energy range of 80–600 eV. The changes in the spectra of the valence band and core levels of Au 4$f$ and Na 2$p$ are associated with a change in the surface topography caused by the deposition of sodium atoms and heating, which led to an increase in the surface area by several times. The surface topography and cathodoluminescence of a layer of gold nanoparticles deposited on a tungsten surface are studied.