Comparison of depth concentration profiles for cesium compounds in fullerene absorbent investigated with X-ray photoelectron spectroscopy

Sekiguchi, Tetsuhiro  ; Yokoyama, Keiichi  ; Yano, Masahiro   ; Uozumi, Yuki*; Asaoka, Hidehito  ; Suzuki, Shinichi; Yaita, Tsuyoshi

The isotope separation of cesium-135 (Cs), 2.3 million years lived nuclides in fission products, is an important issue for the transmutation annihilation. We are developing Cs selective carbon storage materials in order to avoid collision induced reverse isotope exchange of Cs atoms and CsI molecules. We have investigated depth concentration distributions of Cs atom or CsI in C as an absorbent material using electron emission angle-resolved, photon-energy dependent, and Ar-sputtering time dependent X-ray photoelectron spectroscopy (XPS) with synchrotron-radiation. Photon energy dependent XPS of a saturated amount of Cs doped on a C film at room temperature (RT). The energy-dependence of the apparent intensity ratio of Cs 3d and C 1s was scarce. It was found that Cs penetrated well into C, whilst CsI deposited on C surface at RT. However, since some experimental conditions may influence Cs depth profiles, we address this issue.