In situ mechanical testing of cerium oxide nanoparticles in atomic-scale Transmission Electron Microscopy (TEM)

Abstract

In situ nanocompression tests in Electron Microscopy have proved to be an interesting tool for identifying the slip systems involved in plastic deformation. To go further in the investigation of the deformation mechanisms, we report here nanocompression experiments performed in a Cs-corrected Environmental Transmission Electron Microscope. The experiments were successfully performed on bixbyite-Ce${}_2$O${}_3$ nanocubes. Thanks to high resolution imaging, the different steps of the deformation mechanism – dislocation nucleation, dissociation and stacking fault formation – could be evidenced. The formation of stacking fault, unusual in face centered cubic structures, is discussed in light of the crystallographic structure and especially the location of oxygen vacancies.