New Photophysical and Photoelectrochemical Phenomena in Doped Nanocrystals

University Of Washington, Seattle WA

Investigators

Abstract

TECHNICAL SUMMARY This research supported by the Solid State and Materials Chemistry Program seeks to develop new colloidal transition-metal-doped semiconductor nanocrystalline materials that show new photophysical and spectroelectrochemical properties relevant to advanced information-processing, imaging, and energy conversion technologies. Synthetic, analytical, and spectroscopic techniques will be integrated to develop a fundamental understanding of the structure/function relationships that govern the physical properties of these nanocrystals. A balanced research effort incorporating synthetic, spectroscopic, spectroelectrochemical, and analytical approaches will be applied to evaluate the microscopic origins of luminescence saturation in doped semiconductor nanocrystals, the impact of nonradiative decay channels on the intrinsic dual emission of doped semiconductor nanocrystals, the capability of dual-emitting doped semiconductor nanocrystals to probe temperatures in plasmonic microspheres, the microscopic origins of electrobrightening in doped and undoped nanocrystal films, the potential to use electrobrightening for identifying and passivating specific electron or hole traps at nanocrystal surfaces, the technical feasibility of multi-color voltage tunable luminescent films based on combinations of electrobrightened and electroquenched luminescent nanocrystals, and the accessibility of different transition-metal redox states in doped semiconductor nanocrystals. This research will yield new fundamental scientific insights that could alter the ways such materials are understood and applied in various technologies including in information processing, lighting, bioimaging, and energy conversion technologies. NON-TECHNICAL SUMMARY Doped semiconductor nanostructures are ubiquitous in energy conversion, energy storage, and photocatalysis technologies, as well as in information processing and storage technologies, and they are central to numerous futuristic proposed device technologies including in the area of spin-based electronics. The information learned from this project will have broad implications for each of these technologies. This research will address the development of new forms of matter on nanometer length scales made from semiconductors doped with impurities. This project will also yield new chemical strategies for controlling the physical properties of doped nanocrystals. In addition to yielding new fundamental scientific insight and new forms of matter, this project will also provide advanced technical training for participating undergraduate and graduate students to prepare them for future careers in science, engineering, and education. Special emphasis will be placed on integrating research and education at the undergraduate level through aggressive involvement of undergraduates in this research, incorporation of experiments and concepts from this research into the University of Washington undergraduate curriculum, hosting faculty and students from undergraduate institutions as visiting scientists at University of Washington, and mature outreach activities at Seattle-area community colleges and high schools.