2D Electronic Nanomaterials and Analytical STEM

Two dimensional (2D) chalcogenides have gained renewed interest due to their interesting electrical properties such as topological surface states in BI2Se3 and hydrogen evolution catalytic activities in MoS2. Our ability to thin them down to a single layer and their anisotropic bonding nature opens up possibilities for novel heterostructures where we can tailor their electronic properties. I will present chalcogenide nanostructures my group synthesizes and discuss a few promising future research directions on these nanostructures. In the second part of the talk, I will present detailed atomic structure characterizations of InGaAs quantum dots using analytical electron microscopy, in collaboration with Prof. Lee group. In particular, nanoscale 2D elemental maps will show that these quantum dots are not In-rich, challenging the current understanding of the band structure.