Annealing Effect of Absorbing Property for Cs and CsI in Fullerene Investigated by Synchrotron X-ray Photoelectron Spectroscopy

We investigated the effect of annealing on the depth concen-tration profile of the fullerene C-60 material exposed to Cs or CsI vapor, as a potential absorber of Cs-135 by angle-resolved X-ray photoelectron spectroscopy. The effects of mild annealing at around 200(o)C, vapor dosing under heating at around 200(o)C, and the characteristic desorption behavior that occurs at higher tem-peratures were investigated. It was found that, after annealing at 280(o)C or higher, Cs remains in the C-60 films whereas CsI is de-sorbed.