The intentional introduction of heterogeneity at the nanoscale plays a key role in the design of functional nanostructure building blocks. The heterogeneity is frequently manifested in structure, shape, composition, and electronic structure modulation of the nanostructure regions. I will present our research that resulted in two methodologies for post-synthesis modification and symmetry breaking of semiconducting nanostructures using nanowires as the basic building blocks covering two aspects of post-synthesis modification of nanowires:
(I) Ex-situ doping of silicon nanowires.
(II) Self-processing synthesis of coinage metal-semiconductor hybrid structures.
In my talk I will present the new methodologies and the characterization challenges that emerge and that were addressed by several advanced analytical techniques including atom-probe tomography, electron holography, in-situ scanning transmission electron microscopy in liquid and scanning tunneling spectroscopy. The combination of these advanced analytical techniques resulted in significant insights regarding the structure, electronic properties and mechanisms involved in the synthesis of the new type of structures.
