Aude Rothschild

WS2 nanotubes as tips in scanning probe microscopy

WS2 nanotubes a few microns long were attached to microfabricated Si tips and tested afterwards in an atomic force microscope by imaging a “replica” of high aspect ratio, i.e., deep and narrow grooves. These WS2 nanotube tips provide a considerable improvement in image quality for such structures when compared with commercial ultrasharp Si tips. The nanotube tip apex shape was extracted by blind reconstruction from an image of Ti spikes, showing a smooth cylindrical profile up to the end.

Encapsulation of WC within 2H-WS2 inorganic fullerene-like cages

The preparation of WC encapsulated within 2H-WS2 inorganic fullerene-like (IF) cages by sulfidisation is described; the encapsulates were prepared from both high surface area (high Sg) and low surface area (low Sg) WC precursors; for low Sg WC, partial conversion of the carbide to the sulfide only was achieved with 2–20 IF layers obtained around carbide particles, resulting in WC/2H-WS2 composites; the amount of conversion obtained in the case of the high Sg WC depended on the method of preparation of the precursor; total conversion to 2H-WS2 was obtained from a precursor obtained by carburisation of small WO3 particles, while only partial conversion was obtained in the instance of high Sg WC prepared from ball-milled low Sg WC.