Directing the Synthesis of Emergent Colloidal Quantum Dots by Correlated Photophysics and Atomic Structure

通过相关光物理和原子结构指导涌现胶体量子点的合成

• 批准号: 2003310
• 负责人: Sandra Rosenthal
• 金额: $ 45万
• 依托单位: Vanderbilt University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2003310&HistoricalAwards=false
• 关键词: Directing; Synthesis; Emergent; Colloidal; Quantum

The Macromolecular, Supramolecular, and Nanochemistry Program in the Chemistry Division supports Professor Sandra Rosenthal and her group at Vanderbilt University to study new quantum dots that are free of toxic heavy metals. Quantum dots which are nanometer-sized versions of semiconductors represent a success stories arising out of the nanotechnology revolution. Quantum dots are notable for their size-dependent light interactions. Quantum dots are tools for neuroscience as they can be used to track individual proteins on a living cell’s surface. Quantum dots occupy a growing portion of the electronic display market due to the vivid colors they produce. While the use and importance of quantum dots are growing, the best performing quantum dots are composed of cadmium, a toxic heavy metal. Indium-based quantum dots are made from non-toxic materials and show comparable color purity and brightness, but struggle in challenging environments such as those found in biological systems. To accelerate the development of new quantum dots, Professor Rosenthal and her research team are using a method to directly correlate the structure of individual quantum dots with their optical performance. In systems where every atom in each quantum dot matters, this methodology can reveal new insights into how complex quantum dot structures yield specific optical behavior. This research enables scientists and engineers to precisely design and synthesize customized quantum dot light emitters as part of advanced manufacturing efforts. As a part of this project, the next generation of scientists are introduced to the growing field of nanotechnology through undergraduate research opportunities and outreach activities for the middle-school students in rural Tennessee.With this award from the Macromolecular, Supramolecular, and Nanochemistry Program, Professor Rosenthal’s research group develops and studies heavy metal-free colloidal quantum dots, including transition metal-based systems. The heavy metal-free quantum dots are being synthesized with complex architectures with the goal of tuning their brightness and photostability. Ultrafast fluorescence upconversion and nanosecond fluorescence spectroscopy are employed to probe both the short and long-time scale carrier dynamics of the photogenerated electrons and holes revealing the effectiveness of the surface passivation. Advanced analytical electron microscopy in conjunction with aberration-corrected scanning transmission electron microscopy (STEM) are used to reveal the chemical and atomic arrangement of the synthesized quantum dots. Further, correlated single particle nanocrystal spectroscopy with STEM imaging is being used to identify structure-function relationships that provide guidance for subsequent synthesis.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

化学系的大分子，超分子和纳米化学项目支持范德比尔特大学的Sandra Rosenthal教授和她的团队研究不含有毒重金属的新量子点。 量子点是半导体的纳米尺寸版本，代表了纳米技术革命的成功故事。量子点以其尺寸依赖的光相互作用而闻名。 量子点是神经科学的工具，因为它们可以用来跟踪活细胞表面的单个蛋白质。量子点占据了电子显示器市场越来越大的份额，因为它们产生了鲜艳的颜色。虽然量子点的使用和重要性正在增长，但性能最好的量子点是由镉（一种有毒的重金属）组成的。铟基量子点由无毒材料制成，具有相当的颜色纯度和亮度，但在生物系统中发现的具有挑战性的环境中挣扎。为了加速新量子点的开发，Rosenthal教授和她的研究团队正在使用一种方法将单个量子点的结构与其光学性能直接关联起来。在每个量子点中的每个原子都很重要的系统中，这种方法可以揭示复杂量子点结构如何产生特定光学行为的新见解。 这项研究使科学家和工程师能够精确设计和合成定制的量子点光发射器，作为先进制造工作的一部分。作为该项目的一部分，下一代科学家通过本科生研究机会和田纳西州农村中学生的外展活动被引入到日益增长的纳米技术领域。凭借大分子，超分子和纳米化学计划的这一奖项，Rosenthal教授的研究小组开发和研究了不含重金属的胶体量子点，包括过渡金属为基础的系统。不含重金属的量子点正在合成复杂的结构，目的是调节它们的亮度和光稳定性。超快荧光上转换和纳秒荧光光谱探测光生电子和空穴的短时间和长时间尺度的载流子动力学揭示了表面钝化的有效性。先进的分析电子显微镜结合像差校正扫描透射电子显微镜（STEM）用于揭示合成量子点的化学和原子排列。此外，相关单粒子光谱与STEM成像被用来确定结构-功能关系，为后续的合成提供指导。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

项目成果

Quantitative morphological analysis of InP-based quantum dots reveals new insights into the complexity of shell growth

InP基量子点的定量形态分析揭示了壳生长复杂性的新见解

• DOI: 10.1063/5.0149097
• 发表时间: 2023
• 期刊: The Journal of Chemical Physics
• 作者: Click, Sophia M.;Koziel, Alexandra C.;Torres, Ruben;Flores, Sebastian;McBride, James R.;Rosenthal, Sandra J.
• 通讯作者: Rosenthal, Sandra J.