We have carried out a photoemission study using synchrotron radiation of dodecanethiolate-(DT-) passivated Au nanoparticles supported on the highly oriented pyrolytic graphite (HOPG) substrates. From detailed line-shape analyses of Au 4f core-level photoemission spectra of DT-passivated Au nanoparticles, it is found that Au 4f core-level spectra consist of the two components. We attribute these components to the inner Au atoms and surface Au atoms bonded to surface dodecanethiolates. From these results, we discuss the chemical states of the present DT-passivated Au nanoparticles.
We have carried out a photoemission study of dodecanethiolate-͑DT-͒ passivated Ag nanoparticles supported on the highly oriented pyrolytic graphite ͑HOPG͒ substrates. From detailed photoemission measurements, it is found that the Fermi-level onsets in the photoemission spectra of DT-passivated Ag nanoparticles on the HOPG substrates are not the metallic Fermi edge, with the steep slope being away from the Fermi level. We attribute the unusual spectral features in the vicinity of Fermi level to the dynamic final-state effect in photoemission, indicative of the interaction between the nanoparticle and substrate through the surface passivants on a femtosecond time scale.
Photoemission study of dodecanethiolate-passivated Ag nanoparticles supported on the highly oriented pyrolytic graphite (HOPG) has been carried out in order to investigate their nanoparticle-substrate interactions.It is found that the Fermi-level onset in the photoemission spectrum for the present Ag nanoparticle is not the Fermi edge, with the steep slope being away from the Fermi-level. The observed photoemission spectra are well characterized by a theoretical calculation that takes into account the influence of the photohole left behind in the Ag nanoparticle in the photoemission final-state and nanoparticle-substrate interaction on a femotosecond timescale. From these results, we discuss the nanoparticle-substrate interactions through the surface-passivants of the surface-passivated Ag nanoparticles the HOPG substrates.
A photoemission study of dodecanethiol (DT)-capped Au nanoparticles on the highly oriented pyrolytic graphite (HOPG) substrates has been carried out in order to investigate in detail the electronic structures of metallic nanoparticles supported on the substrates. The present DT-capped Au nanoparticles show that the leading edge in the photoemission spectra near the Fermi level is not the Fermi edge, with the midpoint of the steep slope being away from the Fermi level. From these results, we discuss the electronic structures of DT-capped Au nanoparticles, especially nanoparticle-HOPG substrate interaction.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.