CAREER: Core-Shell Interfaces in Colloidal Quantum Dots.

来自阿肯色大学的Colin D. Heyes得到了大分子、超分子和纳米化学项目的支持，他的研究重点是了解半导体量子点（QDs）的光学和电学特性与单粒子水平的核壳界面结构之间的关系。随着带隙工程核壳纳米材料的应用接近灵敏度的极限水平-单粒子和单光子-提高我们对关键核壳界面作用的理解是至关重要的。在这个提案中，在控制合成不同组成的核壳材料方面的专业知识，结合单粒子光谱和先进的高分辨率电子显微镜技术，将用于研究核壳界面上的陷阱态如何对载流子弛化途径做出贡献：1)合成一系列具有不同晶格错配的核壳和核多壳量子点，并在单粒子中对这些界面进行结构表征；2)测定系综和微观光学和电学性质，并将其与核-壳界面结构联系起来；3)研究这些性质如何与壳配体界面和粒子的局部环境耦合。核壳量子点在光电、光电、光催化和高级生物成像等领域具有广泛的应用意义。这种广泛的应用源于这样一个事实，即壳层可以被调整以增强发射或促进载流子捕获、分离和界面转移。为了推进这一系列的技术领域，需要在现代物理化学的多学科方面对学生进行热情和训练。这项建议的教育和外联方面将从三个方面解决这个问题。1)通过举办夏季研讨会，让当地本科院校的本科生（大三和大四）接触到现代物理化学技术，并在化学、物理和生物的界面上进行最近发表的实验；2)利用这个研讨会，通过针对有大量这样的学生的pui来招募代表性不足的少数民族，3)通过首席研究员的网站、YouTube和Facebook传播研讨会实验的视频，以扩大对其他pui、高中和公众的教育影响。

Colin D. Heyes from the University of Arkansas is supported by the Macromolecular, Supramolecular and Nanochemistry Program in research focused on understanding how the optical and electrical properties of semiconductor quantum dots (QDs) are related to the structure of the core-shell interface at the single particle level. As the applications of bandgap-engineered core-shell nanomaterials approach the ultimate level of sensitivity - single particles and single photons - improving our understanding of the role of the critical core-shell interface is of paramount importance. In this proposal, expertise in the controlled synthesis of core-shell materials of varying composition combined with single particle spectroscopy and advanced high resolution electron microscopy techniques will be used to investigate how the trap states at the core-shell interface contribute to the charge carrier relaxation pathways by 1) synthesizing a range of core-shell and core-multishell QDs with different lattice mismatches and structurally characterizing these interfaces in single particles; 2) determining the ensemble and microscopic optical and electrical properties and correlating them to the structure of the core-shell interface; and 3) investigating how these properties are coupled to the shell-ligand interface and the local environment of the particle.Core-shell quantum dots have wide ranging significance for photovoltaics, optoelectronics, photocatalysis and advanced biological imaging applications. This broad range of applications stems from the fact that the shell can be tuned to either enhance emission or to promote charge carrier trapping, separation and interfacial transfer. In order to advance such a range of technological fields, enthusing and training students in the multi-disciplinary aspects of modern physical chemistry is needed. The education and outreach aspects of this proposal will address this issue on three fronts. 1) expose and enthuse undergraduates (juniors and seniors) from local primarily undergraduate institutions (PUIs) by holding a summer workshop that exposes them to modern physical chemistry techniques in the form of performing recently published experiments at the interface of chemistry, physics and biology; 2) use this workshop to recruit under-represented minorities by targeting PUIs with a large body of such students, and 3) disseminate videos of the workshop experiments being performed via the principal investigator's website, YouTube and Facebook to broaden the educational impact to other PUIs, high schools and the general public.