Author : Andrew Kevin Tobias
Publisher :
ISBN 13 :
Total Pages : 206 pages
Book Rating : 4.:/5 (841 download)
Book Synopsis Quantum DOT Synthesis Characterization and Analysis by : Andrew Kevin Tobias
Download or read book Quantum DOT Synthesis Characterization and Analysis written by Andrew Kevin Tobias and published by . This book was released on 2012 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum dot applications are numerous and range from photovoltaic devices and lasers, to bio labeling. Group II-VI semiconductor nanocrystals, specifically CdSe quantum dots, have been shown to be useful in applications such as, imaging, biological labeling, LEDs, lasers and solar cells. To further our understanding of these systems, we have synthesized a wide range of quantum dot samples, and characterized them using spectroscopic techniques. Difficulties in sample reproducibility and variance in the electronic band structure of quantum dots from sample to sample create the necessity for analysis techniques that can accurately and reproducibly provide band energies. Cyclic voltammetry (CV) has been used to estimate HOMO/LUMO levels in molecular species and, similarly, can also be used to estimate valence and conduction band levels in quantum dots. CV has the potential to become a useful tool in engineering new nanocrystal technology, by providing information necessary for predicting and modeling interfacial charge transfer to and from quantum dots. Despite the potential use of CV analysis, limitations arise due to the physical nature of nanocrystals. Solubility and diffusion come into play in solution-state experiments, while sample degradation is an issue in thin films. Carbon paste electrodes have been used in electrochemical studies to eliminate these issues. I will present data obtained using a carbon paste electrode to investigate energy levels in core CdSe and ligands bound to their surface. Importantly, the results of this work allow us to determine HOMO-LUMO energy differences for candidate nanocrystal-molecule electron transfer systems.