Interface electronic structure of alkanethiolate-passivated Au nanoparticles studied by photoelectron spectroscopy

We have carried out the photoemission study of various alkanethiolate- (AT-) passivated Au nanoparticles. From the detailed line-shape analyses of Au $4f$ core-level photoemission spectra, it is found that the interface chemical states are independent on the surface passivants of AT molecules among the AT-passivated Au nanoparticles with the same size. Moreover, the interface electronic structures of AT-passivated Au nanoparticles have been characterized. It is found that the surface-potential shifts due to the interface dipoles accompanying the adsorption of AT molecules are about 0.360.3em0exeV and are independent on the surface passivants of AT molecules. The detailed interface electronic state of AT-passivated Au nanoparticle is discussed.