INSIGHT INTO THE GROWTH MECHANISM OF WS2 NANOTUBES IN THE SCALED-UP FLUIDIZED-BED REACTOR

Abstract

The growth mechanism of WS2 nanotubes in the large-scale fluidized-bed reactor is studied in greater detail. This study and careful parameterization of the conditions within the reactor lead to the synthesis of large amounts (50–100 g/batch) of pure nanotubes, which appear as a fluffy powder, and (400–500 g/batch) of nanotubes/nanoplatelets mixture (50:50), where nanotubes usually coming in bundles. The two products are obtained simultaneously in the same reaction but are collected in different zones of the reactor, in a reproducible fashion. The characterization of the nanotubes, which grow catalyst-free, by a number of analytical techniques is reported. The majority of the nanotubes range from 10 to 50 micron in length and 20–180 nm in diameter. The nanotubes reveal highly crystalline order, suggesting very good mechanical behavior with numerous applications.