Developing in operando structure-property-function guidelines for small molecule organic electron acceptors and its implication on device performance and charge carrier mobility

有机光伏(OPV)技术具有灵活性、重量轻、能源回收期短(即生产其生产所需的能源所需的时间)等独特特性，因此具有显著的经济影响。为了实现更大的商业应用，OPV需要克服效率、稳定性、耐用性以及安全和可持续生产方面的技术挑战。该项目将调查在操作条件下造成口服脊髓灰质炎疫苗有限寿命和效率的工艺。这些研究将使用一套内部和同步加速器衍射和光谱分析工具以及器件制造来进行。该项目团队将通过高中教师参与的创新教育和推广活动，让盐湖城社区参与能源和有机电子主题的研究。此外，项目团队将通过Young&Amp；WISE(女性科学与工程)推广工作，为硅谷经济困难的年轻女性学生提供STEM方面的专业指导和短期研究活动。合理设计和研究受控良好的非富勒烯电子受体的物理和化学性质，对于实现高效、灵活和可溶液处理的有机光伏(OPV)至关重要。虽然在传统的体相异质结结构中，由p型给体聚合物和n型小分子受体组成的OPV的功率转换效率接近15%，但仍然存在着重大的基础知识空白(即形态变化、合适的施主-受体耦合、能级失配)，阻碍了它们的加速开发和商业化。此外，对于表面形态、施主-受主界面、能级排列和器件特性在操纵面条件和偏压作用下如何演变的基础知识很少或根本没有。在这个基础研究项目中，研究团队将1)设计一个基于硫化扭曲的季戊二酰亚胺推进器作为高效电子受体的模型系统；2)开发衍射和光谱表征方法，以阐明在操作条件下与其他分子接触时电子受体的能级排列、分子取向和形态；以及3)研究激子相互作用和自旋过程，以提高功率转换效率。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Organic photovoltaic (OPV) technology has the potential for significant economic impact due to unique features such as flexibility, low weight, and short energy payback time (i.e. the time needed to produce the energy that was required for its production). To achieve greater commercial application, OPVs need to overcome technology challenges in efficiency, stability, durability, and safe and sustainable production. This project will investigate the processes responsible for the limited lifetime and efficiency of OPVs under operating conditions. These studies will be carried out using a suite of in-house and synchrotron diffraction and spectroscopy tools coupled with device fabrication. The project team will engage the Salt Lake City community in energy and organic electronic topics through an innovative education and outreach effort involving high school teachers. Also, the project team will provide professional mentoring and short research activities in STEM to economically disadvantaged young female students in the Valley through the Young & WISE (Women in Science and Engineering) outreach effort.The rational design and investigation of the physical and chemical properties of well-controlled non-fullerene electron acceptors are critical for enabling high efficiency, flexible, and solution processable organic photovoltaics (OPVs). Although, power conversion efficiencies are approaching 15% for OPVs comprising a p-type donor polymer and an n-type small molecule acceptor in a conventional bulk-heterojunction architecture, there are still major fundamental knowledge gaps (i.e., morphology changes, appropriate donor-acceptor coupling, energy level mismatches) that impede their accelerated development and commercialization. Furthermore, there is little to no fundamental knowledge on how morphology, donor-acceptor interfaces, energy level alignments, and device characteristics evolve under operando conditions and bias stress effects. In this fundamental research project, the research team will 1) design a model system based on thionated contorted quaternary perylene diimide propellers as efficient electron acceptors; 2) develop diffraction and spectroscopy characterization approaches to elucidate energy level alignment, molecular orientation, and morphology of electron acceptors when interfaced with other molecules under operating conditions; and 3) investigate exciton interactions and spin processes that could enhance power conversion efficiencies.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.