Large-scale Synthesis of WS sub( 2) Multiwall Nanotubes and their Dispersion, an Update

Recently, we have reported the synthesis of a pure phase of multiwall WS sub( 2) nanotubes in substantial amounts. Nonetheless, the overall yield from the oxide powder to de-agglomerated nanotubes was not very high. To overcome this obstacle, the synthesis of the nanotubes was studied in further detail. This study and careful parameterization of the conditions within the reactor lead to further understanding of the growth mechanism and facilitate the synthesis of large amounts (50-100g/batch) of pure nanotubes with much higher overall yield. The majority of the nanotubes range from 10 to 20 micron in length and 50-120 nm in diameter. The new process produces loosely agglomerated nanotubes that can be easily dispersed in organic solvents and different polymer matrices. In view of its excellent mechanical properties, and its semiconducting characteristics, large number of applications could be anticipated for such nanotubes, especially in reinforcing variety of nanocomposites, sensors, actuators, etc.