Multidimensional photoresponsive molecular architectures for high performance solar cells

该项目旨在了解、开发和应用基于将低禁带分子组装成多维结构的光电功能，以实现下一代高性能体异质结(BHJ)有机太阳能电池(OSC)。我们的集成方法包括新型给体(D)和受体(A)的分子网络，结合形态控制的光增强电荷传输和创新的光增强或捕获结构。虽然先前研究的关键OSC参数，如能级匹配和载流子迁移率，可以在制备之前进行筛选，但作为优化的核心的有源层形态很难通过简单的分子结构分析来预测。在接下来的项目中，我们将利用我们之前的研究成果，结合基于自组装网络和光诱导活性层结构的改进构建块，进行从形态分析到系统形态和结构控制的范式转变。对于内部OSC结构，我们将合成经过优化的具有复杂2D和3D结构的功能基团的perene bisimide A衍生物。通过有效地将材料设计、合成和光伏评估相结合，我们将利用我们最初的增强D-A材料的奎宁共振的概念，识别高迁移率、低带隙的D材料。A和D的协同优化将导致高性能的非富勒烯OSC，这条路线将影响纳米尺度上的分子有序性，而光辅助过程，如通过交联或光诱导传质的光图案化将在微观尺度上构建活性层，不断地与D和A的发展和理论模拟相互作用。图案化不仅用于增强电荷的分离和转移，还将用于产生外部导光和重新分布的光子结构，如基于结构化光聚合物的非周期结构或表面浮雕光栅，从而显著提高整体性能。因此，我们使用光作为控制单元来进行形态和表面结构以及光的收获。多尺度建模将提供对D和A组分的分子结构和电子性质之间的关系以及OSC效率的基本了解。将量子力学计算与原子论和粗粒度分子动力学相结合，我们将预测自组装网络或光图案化网络的形状，支持高级形态学的发展。研究了分子的迁移率和堆积以及聚合物的纠缠或有序/无序跃迁对整体电子性质的影响。因此，理论将有助于为进一步的OSC优化建立设计规则。

This project aims to understand, develop, and apply optoelectronic functionalities based on the assembly of low band gap molecules into multidimensional architectures for the realization of next generation high-performance bulk heterojunction (BHJ) organic solar cells (OSCs). Our integral approach includes molecular networks of novel donors (D) and acceptors (A), photoenhanced charge transport combined with morphology control and innovative light enhancing or harvesting structures. While crucial OSC parameters as energy level matching and charge carrier mobility, studied previously, can be screened prior to fabrication, active layer morphology, which is central for optimization, is hard to predict by simple molecular structure analysis. In the upcoming project, we will exploit our previous results to perform a paradigm shift from morphology analysis to systematic morphology and architecture control combined with improved building blocks based on self-assembled networks and light-induced active layer structuring.For the inner OSC structure, we will synthesize innovative perylene bisimide A derivatives that are optimized in their functional groups allowing complex 2d and 3d structures. By effectively combining material design, synthesis, and photovoltaic evaluation, we will identify high-mobility, low-bandgap D materials, employing our original concept of enhancing the quinoid resonance of D-A materials. Synergetic A and D optimization will lead to high-performance non-fullerene OSCs.While this route will influence molecular order on the nanoscale, light-assisted processes like photo-patterning via crosslinking or photo-induced mass transfer will structure the active layer on the microscale, in constant interplay with D and A development and theoretical modeling. Patterning will not only be used to enhance charge separation and transfer, but also to generate outer light-guiding and redistributing photonic structures, e.g. aperiodic structures or surface relief gratings based on structured photopolymers, considerably improving the overall performance. Thus, we employ light as a control unit for both morphology and surface structuring and light harvesting.Multiscale modeling will provide a fundamental understanding of the relation between molecular structure and electronic properties of the D and A components and the OSC efficiency. Combining quantum-mechanical calculations with atomistic and coarse-grained molecular dynamics, we will predict the shape of self-assembled or photo-patterned networks, supporting the development of an advanced morphology. The effect of molecular mobility and stacking as well as polymer entanglement or order/disorder transitions on the overall electronic properties is studied. Thus, theory will contribute to establishing design rules for further OSC optimization.