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Document Type

Campus-Only Access for Five (5) Years

Degree Name

Doctor of Philosophy (PhD)

Degree Program

Physics

Year Degree Awarded

2018

Month Degree Awarded

May

First Advisor

Michael D. Barnes

Subject Categories

Condensed Matter Physics | Physical Chemistry

Abstract

This dissertation includes the exploration about the following research questions: 1. What is the correlation between the work function and ground state interactions in organic semiconductor assemblies? 2. How do non-covalent chemical doping tune the work function in MoS2? 3. Are there surface charges in the Aluminum doped ZnO nanocrystals (AZO) and what's the evolution of the surface charges and polarizabilities from undoped AZO to doped AZO? 4. How is the homogeneity like during doping in the organic thermoelectric materials? The techniques we employed in the research is the spatially registered Kelvin Probe Force Microscopy and Photoluminescence spectroscopy and imaging, with the ability to reveal and correlate the electronic and structural information. Through the combined techniques, we discovered the correlation of the ground state interactions and the work function in tetraazaterrylene organic semiconductor assemblies, achieved bidirectional tuning of the work function in MoS2, and found direct evidence for large numbers of surface charges in the AZO nanocrystals.

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