Insights into the Structure of MoS$_{2}$ Nanotubes as revealed by aberration corrected STEM

Transition metal chalcogenides like MoS$_{2}$ or WS$_{2}$ are quasi-two dimensional (2D) compounds. Similar to carbon, transitional metal chalcogenides also form close caged structures known as inorganic fullerenes (IF) and nanotubes (INTs). We have sought to use probe aberration corrected electron microscopy for elucidating some important features and aspects of MoS$_{2}$ nanotubes. Thus we have synthesized MoS$_{2}$ nanotubes, and during the course the analysis we have observed some important features, namely, unusual facetted caps and curvatures in these nanotubes. Aberration-corrected scanning transmission electron microscopy (STEM) along with simulated STEM images has been carried out to understand better the structure of the nanotubes. Further details involving the nature of the nanotubes, as well as the structure and bonding of the Mo-S in the nanotubes have been investigated, and our results have revealed various interesting aspects for the first time to our knowledge.