Trap Assisted Dynamical Processes in Semiconductor Nanocrystals

大分子，超分子和纳米化学（MSN）计划支持华盛顿大学的李晓松教授和大卫甘末林教授开发新的纳米级化学结构，这些结构对下一代信息处理或能量转换技术的出现非常有用。 半导体纳米结构中的化学过程在能量转换、能量存储和高效照明以及信息处理和存储技术中无处不在。这种综合的合成方法，光谱学和理论产生了新的和强大的途径，用于描述基本属性，支配功能半导体纳米结构中的重要化学过程。 该合作项目涉及理论计算和实验合成与测量，还为跨材料科学，理论，无机化学，电子结构分析，动力学分析和光谱学的高级跨学科教育和培训提供了一种机制，并为参与的本科生和研究生未来的科学和技术职业做好准备。通过高中和社区外展，本科生研究指导，并与教师在主要本科院校的参与相结合，该项目促进和培养广泛的青年参与科学和工程活动。该项目使用平衡的理论和实验方法，以发展在半导体纳米结构中的各种陷阱辅助动力学过程的基本理解。新的计算方法，使用第一原理自旋哈密顿的时间依赖性密度泛函理论框架内正在开发的预测和建模陷阱辅助动力学过程。结合光谱/光谱电化学技术的新的计算方法被应用到调查的陷阱状态辅助能量转移过程和激发态动力学，使其微观起源被彻底定义。 纳米晶体内的关键结构参数将被系统地化学修饰。理论和实验确定的参数允许调制或控制的陷阱态辅助过程中的杂质含有半导体纳米晶体。

The Macromolecular, Supramolecular and Nanochemistry (MSN) Program supports Professors Xiaosong Li and David Gamelin of the University of Washington to develop new nanoscale chemical structures that are useful for the emergence of next-generation information processing or energy conversion technologies. Chemical processes in semiconductor nanostructures are ubiquitous in energy conversion, energy storage, and efficient lighting, as well as in information processing and storage technologies. This integrated approach of synthesis, spectroscopy, and theory yields new and powerful avenues for describing fundamental properties that govern the important chemical processes in functional semiconductor nanostructures. This collaborative project, which involves both theoretical calculations and experimental synthesis and measurement also provides a mechanism for advanced interdisciplinary education and training that spans materials science, theory, inorganic chemistry, electronic structure analysis, dynamics analysis, and spectroscopy, and prepares participating undergraduate and graduate students for future careers in science and technology. Through a combination of high-school and community outreach, undergraduate research mentoring, and engagement with faculty at primarily undergraduate institutions, this project promotes and fosters participation of a broad spectrum of youth in science and engineering activities.This project uses a balanced theoretical and experimental approach to develop a fundamental understanding of various trap-assisted dynamical processes in semiconductor nanostructures. New computational methods using a first-principles spin-Hamiltonian within the time-dependent density functional theory framework are being developed for predicting and modeling trap-assisted dynamical processes. New computational approaches in conjunction with spectroscopic/spectroelectrochemical techniques are applied to investigations of trap-state assisted energy transfer processes and excited state dynamics that allow their microscopic origins to be defined thoroughly. Key structural parameters within the nanocrystals are to be systematically chemically modified. Theoretical and experimental determination of the parameters allows modulation or control of trap-state assisted processes in impurity-containing semiconductor nanocrystals.