| Abstract
| - Recently, milligram quantities of MoS2 fullerene-likenanotubes and negative curvature polyhedra(generically called inorganic fullerene-like material,IF), were reproducibly obtained by a gas phase reactionfroman oxide precursor (Feldman, Y.; Wasserman, E.; Srolovitz, D. J.;Tenne, R. Science1995, 267, 222.Srolovitz, D.J.; Safran, S. A.; Homyonfer, M.; Tenne, R. Phys. Rev.Lett.1995, 74, 1778). Thepresent work focuses on themechanism of the synthesis of IF-MS2 (M = W, Mo).The IF material is obtained from oxide particles smallerthanca. 0.2 μm, while larger oxide particles result in 2H-MS2platelets. The key step in the reaction mechanism istheformation of a closed layer of MS2, which isolates thenanoparticle from its surroundings and prevents its fusionintolarger particles. Subsequently, the oxide core of the nanoparticleis progressively converted into a sulfide nanoparticlewith an empty core (IF). Taking advantage of this process, wereport here a routine for the fabrication of macroscopicquantities of a pure IF-WS2 phase with a very high yield.As anticipated, the size distribution of the IF materialisdetermined by the size distribution of the oxide precursor. Thepresent synthesis paves the way for a systematicstudy of these materials which are promising candidates for, e.g.,solid lubrication.
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