Abstract:
It is shown that the growth of a nanosized fullerite film in the C60 molecules-Nb(100) surface adsorption system depends essentially on the chemical state of adsorbed sulfur. In particular, sulfur as the surface sulfide NbS with a concentration of (9±0.2) × 1014 cm−2 has almost no effect on the adsorption: as on the pure metal, fullerene molecules from the first and, partially, second layers undergo considerable degradation and do not desorb at any temperatures upon the subsequent heating. On the contrary, C60 molecules retain their structure on a valence-saturated NbS2 monolayer with almost the same surface concentration of S atoms, build a fullerite film as crystallites without the formation of an intermediate monolayer (Volmer-Weber mechanism), and completely leave the surface at 800 K, which remains unchanged and uncontaminated.