Non-Covalent Supramolecular Donor-Acceptor Arrays With Nanocarbon Materials for Light-Harvesting

卟啉及其类似物是众所周知的“生命色素”，参与生物底物的捕光、氧转移和转化。人们已经研究了多种合成的卟啉作为人工捕光材料，其中最好的系统在太阳能光电转换中提供了13%的效率。含二茂铁的卟啉、硼二吡咯亚甲基(BODIPY)和硼氮二吡咯亚甲基(Aza-BODIPY)是重要的捕光材料。要在有机光伏(OPV)中有效地使用这些化合物，需要将这些分子以非共价方式连接到电子受体上，如富勒烯、纳米管和石墨烯。芘基团可以促进与纳米碳材料的这种期望的非共价相互作用。在拟议的计划中，我们将瞄准新的二茂铁(施主)-芘(非共价“胶”)-卟啉/BODIPY/氮杂-BODIPY(天线)杂化材料，这些杂化材料有可能改善OPV的光捕获特性。*我们的短期目标是：(I)制备能够与纳米管材料形成强大的非共价络合物的新的二茂铁-芘-卟啉/BODIPY/氮杂-BODIPY杂化材料。二茂铁供体将与天线的pi-体系完全结合，以促进电子转移到光激发的发色团。(Ii)通过各种光谱和(光谱)电化学方法、X射线结晶学和理论计算来表征具有系统几何和电子性质变化的新材料，以探索其在OPV中的光诱导电子转移性能。(Iii)研究新型供体-受体杂化材料与纳米碳材料之间的非共价络合物。捕光二元体和纳米碳材料之间的非共价络合物将导致长寿命电荷分离态的形成，并提高OPV的效率。作为一个长期目标，对新化合物的系统研究将使我们能够了解生色团的性质、氧化还原中心之间的穿透键和穿透空间距离以及供体和受体与天线的共轭类型如何以及在多大程度上控制这些体系中的氧化还原过程、稳定性和光诱导电子转移性质。理解给体、天线和纳米碳受体之间的电子相互作用是非常重要的，并可能导致在制备用于光收集的纳米级功能材料方面取得突破性进展。这个专门设计的课程特别适合本科生和研究生，他们将在无机和材料化学、光谱学和计算化学领域接受独特的培训，这将使他们能够申请到对技能要求很高的职位。**

Porphyrins and their analogues are well-known "pigments of life", which are involved in light-harvesting, oxygen transfer, and transformation of biological substrates. A variety of synthetic porphyrins have been studied as artificial light-harvesting materials with the best system providing >13% efficiency in the solar light-to-electricity conversion. Ferrocene-containing porphyrins, borondipyrromethenes (BODIPYs), and boronazadipyrromethenes (aza-BODIPYs) are prominent candidates for light-harvesting. Efficient use of such compounds in organic photovoltaics (OPV) requires non-covalent attachment of these molecules to the electron-acceptors such as fullerenes, nanotubes, and graphene. The pyrene group can facilitate such desired non-covalent interactions with nanocarbon materials. In proposed program, we will target new ferrocene (donor) - pyrene (non-covalent "glue") - porphyrin/BODIPY/aza-BODIPY (antennae) hybrids that have a potential to improve light-harvesting characteristics in OPVs.******Our short-term objectives are: (i) to prepare new ferrocene-pyrene-porphyrin/BODIPY/aza-BODIPY hybrids capable of forming strong non-covalent complexes with nanocabron materials. The ferrocene donor will be fully conjugated with the pi-system of the antennae to facilitate electron-transfer to the photoexcited chromophore. (ii) To characterize new materials with systematic variation in geometric and electronic properties by a variety of spectroscopic and (spectro)electrochemical methods, X-ray crystallography, and theoretical calculations in order to probe their photoinduced electron-transfer properties useful in OPVs. (iii) To study non-covalent complexes between new donor-acceptor hybrids and nanocarbon materials. The non-covalent complexes between light-harvesting dyads and nanocarbon materials will result in the formation of long-lived charge-separation states and improve the efficiency of OPV.******As a long-term objective, the systematic investigation of the new compounds will allow us to understand how and to what extent the nature of the chromophore, the through-bond and through-space distance between the redox centers, and the type of donor and acceptor conjugation with the antennae can control redox processes, stability, and photo-induced electron-transfer properties in these systems. The understanding of electronic interactions between donor, antennae, and nanocarbon acceptor is very important and likely will result in groundbreaking advances in preparation of nanoscale functional materials useful for light-harvesting. The specifically designed program is especially suitable for undergraduate and graduate students, who will receive unique training in the fields of inorganic and materials chemistry, spectroscopy, and computational chemistry, which will allow them to apply to positions that require highly desired skills. **