Synthesis, Characterization, and Photophysical Investigations of Doped Semiconductor Nanocrystals

Doped semiconductor nanocrystals (NCs) are an emerging class of new materials, as incorporation of guest ions allows for refinement of their electronic, optical, and magnetic properties beyond that afforded by quantum confinement effects. However, doping semiconductors by impurity atoms has proven elusive for strongly confined colloidal semiconductor nanocrystals due to the synthetic challenges, as well as the lack of fundamental understanding of the electronic structure of doped NCs. Therefore, it is the aim of this dissertation to gain deeper insight into the underlying mechanism of the synthesis of doped materials and the impact of impurities on the electronic structure of the host matrix. Our research has resulted in a microscopic description of dopant electronic structure in the ground and excited states, including the discovery that charge carrier localization on a dopant may result in a modulation of the guest ion’s bonding to the underlying semiconductor matrix. These findings provide a sound scientific for the future developments of more efficient electronic devices.