Recent highlights in advanced transmission electron microscopy techniques: Applications to nanomaterials
In this chapter, recent advances in scanning/transmission electron microscopic techniques and their applications to nanomaterials are highlighted. Aberration corrected electron microscopy is now routinely employed to study carbon nanomaterials, nanoparticles, 2D materials, alloys and heterostructures, etc. However, there have been several significant achievements in employing this technique towards the study of the various nanostructures. Aberration corrected TEM/STEM imaging tends to be very successful in identifying new nanoalloys, enables understanding of the growth mechanisms as well as the behaviour of supported atoms/clusters towards catalytic reactions, etc. HAADF-STEM imaging in combination with spectroscopy is an essential tool for the characterization of new 2D materials, such as borophenes and phosphorenes. At the same time, it provides insights into the structure of hetero-interfaces as well as enables identifying defects and new phases associated with these materials. It is now possible to go down in accelerating voltages upto 15 kV in both TEM/STEM modes and image specimens with minimal damage. It is foreseen, that these new developments in advanced electron microscopic techniques will provide significant possibilities for unravelling new phenomena, as well as explore novel properties of nanomaterials enabling new applications.