Synthesis, Synthetic Mechanism, and Single Particle Microscopy of Colloidal Semiconductor Nanocrystals

University Of Rochester, Rochester NY

Investigators

Abstract

In this project funded by the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Professor Todd Krauss of the University of Rochester is studying tiny inorganic particles called colloidal semiconductor nanocrystals (NCs). These NCs have the potential to impact numerous areas of active research and technology due to their size-dependent properties. However, the lack of a rational synthetic mechanism has impeded advances in NC design and applications. This project investigates new fundamental strategies for low-temperature NC syntheses that are potentially scalable to industrial volumes, and thus are compatible with current chemical manufacturing procedures. Large-scale synthesis of semiconductor NCs, especially those with reduced toxicity, may enable the development of new applications in biology and medicine, optics and photonics. This project provides for the education and training of two graduate students and one undergraduate student. The two graduate students also organize and direct outreach efforts through interfacing with the Rochester Museum and Science Center. A long-standing and significant challenge in the field of colloidal semiconductor NCs is to understand at a fundamental level how NCs are synthesized, and to use this knowledge to make improved NCs in a rational manner. The overall goal in this project is to develop a more detailed understanding of NC synthesis mechanisms in route to synthesizing NCs with improved chemical or photophysical properties. Several experiments are conducted utilizing optical, mass and nuclear magnetic resonance spectroscopies to obtain more complete understanding of the chemical reaction mechanism for the NCs of interest. Also, the important relationship between charge, photoluminescence and impurity atom concentration for doped semiconductor NCs are being determined. These studies will aid in the understanding of unexplained photophysical phenomena in a wide class of nanostructured materials.