Real Time TEM Imaging of Compression and Shear of Single Fullerene-Like MoS₂ Nanoparticle

The deformation and degradation behavior of single inorganic fullerenes nanoparticles of MoS₂ under compression and shear has been observed in real time using a high-resolution transmission electron microscope equipped with a nanoindentation holder. The MoS₂ nanoparticles were compressed using a nanoindenter and a truncated diamond tip. For the first time, real time imaging of the deformation of individual nanoparticles clearly shows first orientation changes in the particle shape during loading process followed by a large deformation and the exfoliation of the outer sheets of the fullerene nested structure. Exfoliation was observed for a contact pressure estimated at 1 GPa. Additional sliding tests performed with the nanoindenter gave evidence for a rolling process for lower contact pressures up to 100 MPa.