Creating Functional Nanocrystal-Molecule Interfaces for Spin-triplet Energy Transfer

创建用于自旋三重态能量转移的功能纳米晶体分子界面

• 批准号: 2003735
• 负责人: Sean Roberts
• 金额: $ 45万
• 依托单位: University of Texas at Austin
• 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 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2003735&HistoricalAwards=false
• 关键词: Creating; Functional; Nanocrystal; Molecule; Interfaces

The Macromolecular, Supramolecular, and Nanochemistry Program in the Chemistry Division supports Professor Sean T. Roberts at the University of Texas at Austin to study light-triggered processes that occur in materials. Light provides the energy that fuels plant growth via photosynthesis, is used in electronics for wireless communication, and even forms the basis for noninvasive medical treatments, such as photodynamic therapy used to treat cancer. However, light transmits its energy in a peculiar manner, via particles known as photons. Different colors of light contain photons with different amounts of energy, and it is important that photon energies be matched to their intended applications. Photons with too little energy are unable to meet their intended task while photons with too much energy waste energy and can cause damage to components. This research project develops materials that reshape light’s energy content by combining pairs of photons into a single high-energy one or converting individual photons into multiple lower-energy photons. Once formed, these materials can serve as energy transfer agents improving solar energy harvesting and quantum computation. In addition to working with students closely on the research projects, Professor Roberts also founded and participates in the GReen Energy At Texas (GREAT) program, which was formed between the University of Texas at Austin and Austin Community College. GREAT aims to increase the number of community college student that earn degrees through targeted mentorship and research experiences.Semiconductor quantum dots chemically functionalized with organic dye molecules offer an ideal interface for photon conversion. Quantum dots energized by light absorption can pass their energy to molecules at their surface, promoting them into spin-triplet exciton states. If formed in high quantity, pairs of spin-triplet excitons can undergo triplet fusion, a process that combines their energy to form a single high-energy spin-singlet state that can radiate light. Likewise, photoexciting the dye molecules can fuel triplet fusion’s inverse process, singlet fission, which creates pairs of triplet excitons that can each pass to the quantum dot to drive infrared light emission. These schemes require a key step, the transfer of a spin-triplet exciton across the quantum dot:molecule interface, yet an understanding of how the structure of these interfaces impacts the rate and efficiency of spin-triplet exciton transfer is elusive. To address this need, Professor Roberts at the University of Texas at Austin directs a team that employs controlled chemical synthesis, 2D NMR and femtosecond time-resolved spectroscopies, and electronic structure calculations. The research team investigates how the chemical structure of quantum dot:molecule interfaces formed by two complementary quantum dot materials of PbS and Si impact spin-triplet exciton transfer. This project contributes to the creation of new hybrid organic:inorganic junctions for light-driven production of energy and fuels as well as materials that use spin entanglement for quantum computation and information storage.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.

化学部的大分子，超分子和纳米化学计划支持德克萨斯大学奥斯汀分校的Sean T. Roberts教授，研究材料中发生的光触发过程。光提供了通过光合作用燃料生长的能量，用于无线通信中的电子产品，甚至构成了非侵入性医疗治疗的基础，例如用于治疗癌症的光动力疗法。然而，光通过称为照片的粒子以特殊的方式传输其能量。不同颜色的光包含具有不同能量的照片，重要的是要将光子能量与预期应用相匹配。能量太少的光子无法完成其预期的任务，而能量浪费过多的照片可能会对组件造成损害。该研究项目开发了通过将一对照片组合为单个高能材料或将单个照片转换为多个低能量照片的材料来重塑光的能量含量。一旦形成，这些材料可以用作改善太阳能收集和量子计算的能源传递剂。除了与学生密切合作研究项目外，罗伯茨教授还创立了德克萨斯州（Great）计划的绿色能源计划，该计划是在德克萨斯大学奥斯汀大学和奥斯汀社区学院之间成立的。伟大的目的是增加通过有针对性的精神训练和研究经验获得学位的社区大学生的数量。使用有机染料分子化学功能化功能化功能，为光子转换提供了理想的接口。通过轻滥用能量的量子点可以将它们的能量传递给表面的分子，从而将它们促进到旋转三个刺激的状态。如果以高量形式形成，成对的自旋三个旋转激子可以进行三重态融合，该过程结合了能量以形成一个可以辐射光的单个高功能自旋态状态。同样，染料分子的光激发可以为三胞胎融合的逆过程，单个裂变燃料，从而产生成对的三重态激子，每个裂变都可以传递到量子点以驱动红外光发射。这些方案需要一个关键步骤，即旋转三个旋转激子在量子点上的转移：分子界面，但了解这些接口的结构如何影响自旋三刺激刺激转移的速率和效率是弹性的。为了满足这一需求，德克萨斯大学奥斯汀分校的罗伯茨教授指导了一个员工控制化学合成，2D NMR和fomtsecond时时间分辨光谱的团队以及电子结构计算。研究小组研究了如何由PBS的两种完整量子点材料和SI撞击Spin-Triplet Inventon转移形成的量子点的化学结构：分子界面。该项目有助于创建新的混合有机体：无机连接能源和燃料的生产以及使用旋转纠缠进行量子计算和信息存储的材料。该奖项反映了NSF的法定任务，并通过使用该基金会的智力功能和宽广的影响来评估NSF的法定任务，并被认为是珍贵的支持。

项目成果

Research-Focused Approach for Introducing Undergraduate Students to Aromatic Organic Synthesis at a Community College

在社区学院向本科生介绍芳香族有机合成的以研究为中心的方法

• DOI: 10.1021/acs.jchemed.2c00662
• 发表时间: 2023
• 期刊: Journal of Chemical Education
• 影响因子: 3
• 作者: Boette, Jessica T.;Daniel, Kira M.;Lietzke, Josephine W.;Amorde, Shawn M.;Roberts, Sean T.
• 通讯作者: Roberts, Sean T.