Size and support effects in the photoelectron spectra of small TiO2 particles

Abstract
Three different TiO2 samples in the form of bulk material, colloidal particles and small clusters supported on SiO2 have been studied by extended x‐ray adsorption fine structure (EXAFS), UV‐visible, transmission electron microscopy (TEM) and XPS. The different values of the Ti 2p binding energies and the Auger parameter of Ti found for each sample show that the photoemission processes in these oxide materials are influenced by size and support effects. A difference in the relaxation energy of −1.1 eV is found for the TiO2/SiO2 sample with respect to TiO2, which is attributed to an effect of the silica support.