Collaborative Research: The Impact of Mesoscale Structure on Multiexciton Dynamics of Macromolecules

这个合作项目研究了有机聚合物在下一代太阳能电池和其他光活性电子设备中的设计方式的细节。一种有希望但未经证实的有效利用光能的方法涉及一类特殊的有机分子，当它们正确组装时，可以回收通常作为热量损失的能量。然而，以最佳方式组织这些分子已被证明是一项挑战，因此这种方法的有益影响迄今尚未实现。该项目开发了一种组装光捕获分子的新方法，使它们以刷子状排列。研究人员使用超快相机来研究组件的能量流动，并利用这些信息来优化其结构。从这些研究中得出的发现可以导致能源和信息应用的变革性技术。该合作为参与的学生提供了机会：发展跨学科的沟通技能;团队合作;应对各自核心学科之外的挑战;将他们的发现传播给化学家，物理学家和整个社区。主要研究人员专注于针对纽约哈莱姆社会经济挑战社区的外联活动，以及年轻的化学家和博士后科学家，特别强调那些属于科学代表性不足的群体的人。多重激子的产生是电子物理学中一个快速发展的领域，但还没有得到很好的理解。多激子产生的分子形式是单重态裂变-从单个光子产生两个独立的三重态激子。从这种光捕获机制，可以设想非常规激子动力学来利用a）当从一个光子产生两个激子/电荷载流子时产生的放大特性（光电子学），B）自旋相关量子态的快速布居（量子信息），或c）局部多电子反应中心的激活（光化学和电子转移）。这一建议是植根于有机大分子的结构-性能关系的基础研究，管理的单线态裂变多激子动力学必要的设备架构的未来实现。研究人员使用分子工程方法来控制基本的多激子动力学和多个长度尺度上的激子传输-从单个分子（三重态对形成过程）到纳米/微米尺度（自由三重态形成和传输）。了解发色团本身的化学性质及其空间排列的影响，战略性地束缚在大分子中，该奖项反映了NSF的法定使命，并通过利用基金会的智力价值和更广泛的知识价值进行评估，被认为值得支持。影响审查标准。

This collaborative project studies intimate details of the way organic polymers can be designed for uses in next-generation solar cells and other light-active electronic devices. One promising but unproven way of harnessing light-energy efficiently involves a special class of organic molecules that, when properly assembled, can recover energy that is normally lost as heat. However, organizing these molecules in the optimal way has proven to be a challenge, such that the beneficial impacts of this approach have not been realized to date. This project develops a new approach to assembling light harvesting molecules so that they are organized in a brush-like arrangement. The researchers use ultrafast cameras to study the flow of energy of the assemblies and use this information to optimize their structures. The discoveries that ensue from these studies can lead to transformative technologies for energy and information applications. The collaboration provides the participating students with opportunities to: develop interdisciplinary communication skills; work in teams; tackle challenges outside their respective core subject; disseminate their findings to chemists, physicists, and the community as a whole. The principal investigators focus on outreach activities targeting socioeconomically challenged communities in Harlem, NY, as well young chemists and postdoctoral scientists, with particular emphasis on those who belong to under-represented groups in science. Multiple exciton generation is now a rapidly growing area in photophysics that has yet to be acutely understood. The molecular version of multiple exciton generation is singlet fission – the generation of two independent triplet excitons from a single photon. From this light harvesting mechanism, unconventional exciton dynamics can be envisioned to exploit a) the amplification properties that result when two excitons/charge carriers are created from one photon (optoelectronics), b) the rapid population of spin correlated quantum states (quantum information), or c) the activation of localized multielectron reaction centers (photochemistry and photocatalysis). This proposal is rooted in fundamental studies of organic macromolecule structure-property relationships that govern the singlet fission multiexciton dynamics necessary for future implementations in device architectures. The researchers use a molecular engineering approach to control fundamental multiexciton dynamics and exciton transport across multiple length scales – from individual molecules (triplet pair formation processes) to nano-/micro-scales (free triplet formation and transport). Understanding the influence of the chemical nature of the chromophores themselves and their spatial arrangement, strategically tethered within macromolecules, provides the fundamental information necessary to solve some of the unifying and inherent challenges in developing next generation singlet fission device concepts.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.