Author/Authors :
Puglia، نويسنده , , C. and Bennich، نويسنده , , P. and Hasselstrِm، نويسنده , , J. and Brühwiler، نويسنده , , P.A. and Nilsson، نويسنده , , A. and Li، نويسنده , , Z.Y. and Rudolf، نويسنده , , P. and Mهrtensson، نويسنده , , N.، نويسنده ,
Abstract :
The adsorption of O2 onto a dispersed (low coverage) phase of K on graphite has been characterized by X-ray photoemission and X-ray absorption spectroscopy. We identify two oxygen adsorption phases before physisorbed oxygen appears. The first species dominates at low O2 exposures whereas the second one, which is probably due to oxygen adsorbed in a superoxo-like configuration (O−δ2, δ⩽1), is dominant at higher oxygen coverage. As a function of increasing oxygen dose, we confirm that the charge, initially donated by the potassium adlayer to the graphite, is gradually withdrawn from the substrate.
Keywords :
Oxygen , alkali metals , X-ray photoelectron spectroscopy , X-ray absorption spectroscopy , Graphite
