New Photophysical and Photoelectrochemical Phenomena in Doped Nanocrystals

技术总结这项研究由固态和材料化学计划支持，旨在开发新的胶体过渡金属掺杂半导体纳米晶材料，这些材料显示出与先进的信息处理、成像和能量转换技术相关的新的光物理和光谱电化学性质。合成、分析和光谱技术将被整合在一起，以发展对支配这些纳米晶体的物理性质的结构/功能关系的基本理解。结合合成、光谱、光谱电化学和分析方法的平衡研究工作将用于评估掺杂半导体纳米晶体中发光饱和的微观来源、非辐射衰减通道对掺杂半导体纳米晶体的本征双发射的影响、双发射掺杂半导体纳米晶体探测等离子体微球中温度的能力、掺杂和未掺杂纳米晶体薄膜中电致发光的微观来源、利用电致发光来识别和钝化纳米晶体表面的特定电子或空穴陷阱的可能性、基于电致发光和电致猝灭发光纳米晶体组合的多色电压可调发光薄膜的技术可行性、以及掺杂半导体纳米晶体中不同过渡金属氧化还原状态的可获得性。这项研究将产生新的基础性科学见解，可能改变对此类材料的理解和在各种技术中的应用，包括在信息处理、照明、生物成像和能量转换技术中。非技术总结掺杂半导体纳米结构在能量转换、能量存储和光催化技术以及信息处理和存储技术中普遍存在，它们是许多未来提出的器件技术的核心，包括自旋电子领域。从该项目中获得的信息将对这些技术中的每一项产生广泛的影响。这项研究将致力于开发纳米级物质的新形式，这些物质由掺杂杂质的半导体制成。该项目还将产生控制掺杂纳米晶体物理性质的新化学策略。除了产生新的基本科学见解和新的物质形式外，该项目还将为参与项目的本科生和研究生提供高级技术培训，为他们未来在科学、工程和教育领域的职业生涯做好准备。将特别强调通过本科生积极参与这项研究，将这项研究的实验和概念纳入华盛顿大学本科生课程，接待来自本科生机构的教职员工和学生作为华盛顿大学的访问科学家，以及在西雅图地区的社区学院和高中开展成熟的外联活动，从而整合本科生层面的研究和教育。

TECHNICAL SUMMARYThis 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 SUMMARYDoped 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.