title: Au nanoparticles on a templating TiO(x)/Pt(111) ultrathin polar film: a photoemission and photoelectron diffraction study.
abstract: We present an in-depth investigation of Au nanoparticles self-assembled on a zigzag-like TiO(x)/Pt(111) ultrathin polar film, whose structure is known in great detail. The peculiar pattern of defects (picoholes) templates a linear array of size-selected (ca. 1 nm) Au nanoparticles without disruption of the titania layer, as observed by scanning tunneling microscopy. Their structure and electronic properties have been investigated by several large-area spectroscopic tools, i.e. high-resolution core and valence level photoemission and angle-scanned and energy-scanned photoelectron diffraction. The comparison between experimental data and density functional theoretical calculations indicates that the Au atoms landing on the oxide film are rather mobile, and that the picoholes can act as effective trapping and nucleation centers for the growth of the Au nanoparticles. All the experimental results are in concord in indicating that the Au NPs are flat islands with a maximum thickness of 2-3 layers exposing the (111) surface.
authors.affiliation: Dipartimento di Scienze Chimiche and ISTM-CNR, CNR-INFM and INSTM Research Units, Università di Padova, Padova, Italy.
authors.forename: Gian Andrea
authors.initials: GA
authors.lastname: Rizzi
authors.forename: Francesco
authors.initials: F
authors.lastname: Sedona
authors.forename: Luca
authors.initials: L
authors.lastname: Artiglia
authors.forename: Stefano
authors.initials: S
authors.lastname: Agnoli
authors.forename: Giovanni
authors.initials: G
authors.lastname: Barcaro
authors.forename: Alessandro
authors.initials: A
authors.lastname: Fortunelli
authors.forename: Emanuele
authors.initials: E
authors.lastname: Cavaliere
authors.forename: Luca
authors.initials: L
authors.lastname: Gavioli
authors.forename: Gaetano
authors.initials: G
authors.lastname: Granozzi
mesh_terms: D004583:Electrons; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry*; D055668:Photochemical Processes; D010984:Platinum / Q000737:chemistry*; D011789:Quantum Theory; D013057:Spectrum Analysis; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: C009495:titanium dioxide; D010984:Platinum; D006046:Gold; D014025:Titanium