Fullerene-like materials and nanotubes from inorganic compounds with a layered (2-D) structure

It was shown that nanoclusters of layered compounds, like MoS2 fold into hollow cage structures of various shapes (IF), including spherical and polyhedral structures, nanotubes of a mum length, etc. Following this discovery a few methodologies for the systematic synthesis of large amounts of MoS2 and WS2 nanotubes were pursued. Recently, nanotubes from various other layered compounds were synthesized. The structural, optical and electrochemical properties of MoS2 (WS2) and other nanotubes were investigated in some detail. It was found that MoS2 nanotubes are semiconductors with a tunable bandgap, which decreases, as the diameter of the nanoparticle decreases. The fullerene-like WS2 and MoS2 nanparticles were found to have interesting tribological properties, which makes them suitable as both additives to lubricating fluids and as dry lubricants, suggesting numerous applications for these nanomaterials. (C) 2002 Elsevier Science B.V. All rights reserved.