Interaction between adsorbed hydrogen and potassium on a carbon nanocone containing material as studied by photoemission

Hydrogen adsorption on a potassium doped carbon nanocone containing material was studied by photoelectron spectroscopy and work function measurement. The valence band spectra indicate that there is charge transfer from potassium to carbon. Upon deposition on carbon potassium is in its ionic state for lower doping and shows both ionic and metallic behavior at higher doping. Adsorption of hydrogen facilitates diffusion of potassium on the carbon material as seen by changes in the K_2p core level spectrum. Variations in the measured sample work function indicate that hydrogen initially adsorb on the K dopants and subsequently adsorb on the carbon cone containing material