Electronic states of K 2p and C 1s core levels and valence bands for KχC60 (χ=0≈6.3) have been studied by X-ray photoelectron spectroscopy (XPS). We find two different chemical states of potassium with binding energy 293.8 and 294.9 eV. The K 2p 3 2 line becomes a single peak at χ = 6.3. These results are discussed in terms of the sites occupied by K in KχC60. The C 1s line (285.1 eV) for C60 is shifted by 0.3 eV to the side of higher binding energy by a very small amount of K, which is consistent with the shift of the valence band. The other line at 284.4 eV appears at 10 min evaporation (χ = 0.8). The intensity of the former is reduced and that of the latter increases with the evaporation time.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering