The electronic structures and the work functions of pristine and Cs-intercalated single-walled carbon nanotube bundles were investigated using ultraviolet photoemission spectroscopy. The valence bands of the pristine bundles were considerably altered from those of graphite. A spectral shift to the higher binding energy side was observed in the Cs-intercalated sample. The work function of the pristine bundles was found to be 4.8 eV, which is 0.1-0.2 eV larger than that of graphite. A drastic decrease of the work function to about 2.4 eV was observed in the Cs-intercalated sample.

We used spectroscopic photoemission and low-energy electron microscopy to investigate the electronic properties of epitaxial few-layer graphene grown on 6H-SiC͑0001͒. Photoelectron emission microscopy ͑PEEM͒ images using secondary electrons ͑SEs͒ and C 1s photoelectrons can discriminate areas with different numbers of graphene layers. The SE emission spectra indicate that the work function increases with the number of graphene layers and that unoccupied states in the few-layer graphene promote SE emission. The C 1s PEEM images indicate that the C 1s core level shifts to lower binding energies as the number of graphene layers increases, which is consistent with the reported thickness dependence of the Dirac point energy.

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The thermal decomposition pathway of an ultrathin oxide layer on Ge(100) and Si(100) surfaces is examined by synchrotron radiation photoelectron spectroscopy and ultraviolet photoelectron spectroscopy with helium I radiation. The as-prepared oxide layer consists of a mixture of oxides, namely, suboxides and dioxides, on both the surfaces. Upon annealing, the oxide layers decompose and desorb as monoxides. However, we find that the decomposition pathways are different from each other. On annealing Ge oxides, GeO2 species transform to GeO and remain on the surface and desorb at >420 °C. In contrast, annealing of Si oxides results in the transformation of SiO to SiO2 up to temperatures (∼780 °C) close to the desorption. At higher temperatures, SiO2 decomposes and desorbs, implying a reverse transformation to volatile SiO species.