NSERC-DFG SUSTAIN - Enhanced solar-energy capture through optimization of up- and down-conversion in organic molecules

该提案概述了一项跨学科计划，旨在通过合成富碳分子和材料来扩大太阳能捕获和转换的范围。战略性设计的有机分子将被用来克服当前一代用于将光转化为电的过程所固有的热力学限制。具体来说，分子设计可以用来回答关于两个过程的基本和应用问题，单重态裂变（SF）和三重态-三重态湮灭上转换（TTA-UC）。有机材料中这两个过程的结合为下一代利用太阳能的设备提供了提高效率的潜力。我们提出，并苯的逐步取代将允许掺入可以提供稳定性、溶解性和功能的基团（并苯=具有苯环的线性稠合序列的分子）。精确控制并苯的结构将有助于通过SF和TTA-UC进行太阳能转换。然后将精心的分子设计与世界领先的理论和物理表征相结合，以了解，优化和实施太阳能电池中的有机分子。光物理分析将提供一个详细的机械理解SF和TTA-UC通过毫微微，皮科，纳米和微秒分辨率的实验。换句话说，我们使用光谱学在时间范围内“观察”分子，从快至千万亿分之一秒到慢至千分之一秒。为了理解SF和TTA-UC的基本方面，我们将依赖于复杂的理论和计算方法。这些模拟提供了这些超快过程的理论推导模型，这些超快过程在分子吸收光后被光谱观察到。再加上实验测量，一个整体的图片开发既要了解个别类别的分子，以及计划将其实施到太阳能转换计划。

This proposal outlines an interdisciplinary plan to expand the boundaries of solar-energy capture and conversion through the synthesis of carbon-rich molecules and materials. Strategically designed organic molecules will be used to overcome the thermodynamic limitations inherent to the current generation of processes used to convert light into electricity. Specifically, molecular design can be used to answer both fundamental and applied questions regarding two processes, singlet fission (SF) and triple-triplet annihilation upconversion (TTA-UC). The combination of these two processes in organic materials offers the potential for improved efficiency in the next generation of devices to harness solar energy. We propose that the stepwise substitution of acenes will allow incorporation of groups that can provide stability, solubility, and function (acenes = molecules featuring a linearly fused sequence of benzene rings). Precise control of the structure of acenes will facilitate solar-energy conversion through SF and TTA-UC. Careful molecular design is then combined with world-leading theoretical and photophysical characterization to understand, optimize, and implement organic molecules in solar cells. Photophysical analyses will provide a detailed mechanistic understanding of SF and TTA-UC through femto-, pico-, nano-, and micro-second-resolved experiments. In other words, we use spectroscopy to "watch" molecules over time frames as fast as one quadrillionth of a second to as slow as one thousandth of a second. To understand fundamental aspects of SF and TTA-UC, we will rely on complex theoretical and computational methods. These simulations provide theoretically derived models of these ultrafast processes that are spectroscopically observed after the molecules absorb light. Coupled with experimental measurements, a wholistic picture is developed both to understand individual classes of molecules as well as plan for their implementation into solar conversion schemes.