The adsorption and desorption of n-alkanethiol monolayers on Au(111) have been studied under ultrahigh-vacuum condition by the use of scanning tunneling microscopy (STM), thermal desorption spectroscopy (TDS), and Auger electron spectroscopy (AES). Molecularly resolved STM observations for the alkanethiol monolayers have revealed that at least four different phases evolve during growth, which results in a multistep growth of the monolayer. The desorption species drastically changes at a critical coverage, which is accompanied by a structure change from a low-density flat-lying phase to a denser standing-up phase: While the latter phase bimolecularly desorbs as disulfides, the former phase unimolecularly desorbs as thiolate radicals. The coverage-dependent change of the desorption mode is explained in terms of the difference in the molecule-substrate bonding.

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A size and condensation controlled Pd nanoparticle is reported. The Pd nanoparticles are prepared by a gas condensation method with He gas, so called dry process. A fabrication of the nanoparticle by means of the dry process is an excellent way, because there are little contaminations on the most lateral surface of the nanoparticle than the nanoparticle by the wet process. Characterizations by TEM and AFM show that the fabricated Pd nanoparticle has a spherical shape, a few nm size in diameter and highly dispersed on the substrate. It is found that there are two chemical states in the Pd nanoparticle. One is an oxidized part at the surface and the other is a bulk part.

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Rhodium on a La-containing ZrO2 support effectively eliminated NOx from a synthetic auto exhaust gas under fluctuating oxygen conditions. Rhodium particles maintained a low oxidation state on the ZrO2-La2O3 mixed oxide even after treatment with 5% O2 at 773 K, highlighting the significant effect of the La addition.

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The charging effect often complicates photoemission spectroscopy and x-ray absorption spectroscopy of an insulating material. Here, monolayer graphene was used as a conductive layer to prevent the charging effect of insulating substrates such as glass and LiNbO3. Charging-free spectra were obtained with various photon energies ranging from vacuum ultraviolet light to hard x-rays. This method could also be applied to photoemission spectroscopy of epoxy adhesives and to photoemission electron microscopy of an insulating film. Photoelectron transmissivities for the transferred graphene film were evaluated over a wide kinetic energy range from 29 to 7910 eV. A minimum transmissivity of ∼0.1 was found at a kinetic energy of ∼60 eV, which rose to 0.86 at 7910 eV. In terms of the kinetic energy dependence of the transmissivity, this method is especially suitable for conventional and hard x-ray photoelectron spectroscopy.